Journal articles: 'Bacterial polymers'

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Secor, Patrick R., Lia A. Michaels, Anina Ratjen, Laura K. Jennings, and Pradeep K. Singh. "Entropically driven aggregation of bacteria by host polymers promotes antibiotic tolerance inPseudomonas aeruginosa." Proceedings of the National Academy of Sciences 115, no. 42 (October 1, 2018): 10780–85. http://dx.doi.org/10.1073/pnas.1806005115.

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Bacteria causing chronic infections are generally observed living in cell aggregates suspended in polymer-rich host secretions, and bacterial phenotypes induced by aggregated growth may be key factors in chronic infection pathogenesis. Bacterial aggregation is commonly thought of as a consequence of biofilm formation; however the mechanisms producing aggregation in vivo remain unclear. Here we show that polymers that are abundant at chronic infection sites cause bacteria to aggregate by the depletion aggregation mechanism, which does not require biofilm formation functions. Depletion aggregation is mediated by entropic forces between uncharged or like-charged polymers and particles (e.g., bacteria). Our experiments also indicate that depletion aggregation of bacteria induces marked antibiotic tolerance that was dependent on the SOS response, a stress response activated by genotoxic stress. These findings raise the possibility that targeting conditions that promote depletion aggregation or mechanisms of depletion-mediated tolerance could lead to new therapeutic approaches to combat chronic bacterial infections.

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van Loosdrecht, M. C. M., M. A. Pot, and J. J. Heijnen. "Importance of bacterial storage polymers in bioprocesses." Water Science and Technology 35, no. 1 (January 1, 1997): 41–47. http://dx.doi.org/10.2166/wst.1997.0008.

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In waste water treatment processes microorganisms are subjected to a feast and famine regime. For sequencing batch processes this is often even more pronounced. Based on literature reports and own research it is hypothesized that in general microorganisms respond to these feast-famine regimes by accumulating storage polymers (polyhydroxyalkanoates) when substrate is present. The storage polymers are used for growth when the external substrate is depleted. In this manner the organisms are capable to balance their growth. A general hypothesis explaining polymer formation is developed. The advantages and disadvantages of this formation of storage polymers for the operation of SBR processes is discussed.

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Carrasco-Acosta, Marina, Marta Santos-Garcia, and Pilar Garcia-Jimenez. "Marine Bacteria Associated with Colonization and Alteration of Plastic Polymers." Applied Sciences 12, no. 21 (November 1, 2022): 11093. http://dx.doi.org/10.3390/app122111093.

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The aim of this work was molecular identification of bacteria associated with marine sand at the drift line, where most plastic debris is deposited, and evaluation of the alteration of plastic polymers by them. Bacterial communities growing on plastic polymer surfaces may differentially cause surface alteration through exopolysaccharide production. This alteration can be analyzed by changes in spectra regions of colonized polymers compared to uncolonized polymers using Fourier Transform Infrared Spectroscopy (FTIR). In this study, bacteria located in sand at the drift line above sea water, where microplastics are most abundant, were isolated and identified through 16S rRNA. Six of the identified species produced exopolysaccharides, namely Bacillus thuringiensis, B. cereus, Bacillus sp. Proteus penneri, Alcaligenes faecalis and Myroides gitamensis. These bacteria species were inoculated into plates, each containing two frequently reported types of polymers at the drift line. Specifically, the two types of plastic polymers used were polypropylene and polystyrene spheres in whole and mechanically crushed states. Differences in bacterial growth were reported as inferred from weight increase of polypropylene and polystyrene spheres after 1-year long culture. Results also showed that Alcaligenes faecalis, Bacillus cereus and Proteus penneri colonized polypropylene spheres and modified spectra regions of FTIR. It is concluded that bacteria located in sand can be considered plastic-altering bacteria as changes in FTIR-spectra of polymers can be related to bioalteration.

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Deng, Shuhua, Anfu Chen, Weijia Chen, Jindi Lai, Yameng Pei, Jiahua Wen, Can Yang, et al. "Fabrication of Biodegradable and Biocompatible Functional Polymers for Anti-Infection and Augmenting Wound Repair." Polymers 15, no. 1 (December 28, 2022): 120. http://dx.doi.org/10.3390/polym15010120.

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The problem of bacteria-induced infections threatens the lives of many patients. Meanwhile, the misuse of antibiotics has led to a significant increase in bacterial resistance. There are two main ways to alleviate the issue: one is to introduce antimicrobial agents to medical devices to get local drug releasing and alleviating systemic toxicity and resistance, and the other is to develop new antimicrobial methods to kill bacteria. New antimicrobial methods include cationic polymers, metal ions, hydrophobic structures to prevent bacterial adhesion, photothermal sterilization, new biocides, etc. Biodegradable biocompatible synthetic polymers have been widely used in the medical field. They are often used in tissue engineering scaffolds as well as wound dressings, where bacterial infections in these medical devices can be serious or even fatal. However, such materials usually do not have inherent antimicrobial properties. They can be used as carriers for drug delivery or compounded with other antimicrobial materials to achieve antimicrobial effects. This review focuses on the antimicrobial behavior, preparation methods, and biocompatibility testing of biodegradable biocompatible synthetic polymers. Degradable biocompatible natural polymers with antimicrobial properties are also briefly described. Finally, the medical applications of these polymeric materials are presented.

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Ringenberg, L., A. Winkel, O. Kufelt, P. Behrens, M. Stiesch, and W. Heuer. "The Effectiveness of Poly-(4-vinyl-N-hexylpyridiniumbromide) as an Antibacterial Implant Coating: AnIn VitroStudy." International Journal of Dentistry 2011 (2011): 1–11. http://dx.doi.org/10.1155/2011/859140.

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The clinical success of osseointegrated dental implants depends on the strong attachment of the surrounding hard and soft tissues. Bacterial adhesion on implant surfaces can cause inflammatory reactions and may influence healing and long-term success of dental implants. Promising implant coatings should minimize bacterial adhesion, but allow epithelial and connective tissue attachment. Therefore, the present study has examined the bioactive effect of poly-(4-vinyl-N-hexylpyridiniumbromide) regarding typical oral bacteria as well as cytotoxicitiy to human cells considering different methods of connecting polymers to silicate-containing surfaces. The results revealed that the application of putative antibacterial and biocompatible polymer in coating strategies is affected by a variety of parameters. Published findings regarding reduced bacterial adhesion could not be verified using oral pathogens whereas hexylated polymers seem problematic for strong adhesion of soft tissue. Concerning innovative coatings for dental implants basic aspects (surface roughness, thickness, alkylation, combination with other polymers) have to be considered in further investigations.

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Fujiwara, Natsumi, Hiromichi Yumoto, Koji Miyamoto, Katsuhiko Hirota, Hiromi Nakae, Saya Tanaka, Keiji Murakami, Yasusei Kudo, Kazumi Ozaki, and Yoichiro Miyake. "2-Methacryloyloxyethyl phosphorylcholine (MPC)-polymer suppresses an increase of oral bacteria: a single-blind, crossover clinical trial." Clinical Oral Investigations 23, no. 2 (May 16, 2018): 739–46. http://dx.doi.org/10.1007/s00784-018-2490-2.

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Abstract Objectives The biocompatible 2-methacryloyloxyethyl phosphorylcholine (MPC)-polymers, which mimic a biomembrane, reduce protein adsorption and bacterial adhesion and inhibit cell attachment. The aim of this study is to clarify whether MPC-polymer can suppress the bacterial adherence in oral cavity by a crossover design. We also investigated the number of Fusobacterium nucleatum, which is the key bacterium forming dental plaque, in clinical samples. Materials and methods This study was a randomized, placebo-controlled, single-blind, crossover study, with two treatment periods separated by a 2-week washout period. We conducted clinical trial with 20 healthy subjects to evaluate the effect of 5% MPC-polymer mouthwash after 5 h on oral microflora. PBS was used as a control. The bacterial number in the gargling sample before and after intervention was counted by an electronic bacterial counter and a culture method. DNA amounts of total bacteria and F. nucleatum were examined by q-PCR. Results The numbers of total bacteria and oral streptcocci after 5 h of 5% MPC-polymer treatment significantly decreased, compared to the control group. Moreover, the DNA amounts of total bacteria and F. nucleatum significantly decreased by 5% MPC-polymer mouthwash. Conclusions We suggest that MPC-polymer coating in the oral cavity may suppress the oral bacterial adherence. Clinical relevance MPC-polymer can be a potent compound for the control of oral microflora to prevent oral infection.

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Tyagi, Anju, and Abhijit Mishra. "Methacrylamide based antibiotic polymers with no detectable bacterial resistance." Soft Matter 17, no. 12 (2021): 3404–16. http://dx.doi.org/10.1039/d0sm02176h.

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We report the synthesis of methacrylamide-based polymers with high antibacterial efficacy and selectivity. The polymers disrupt bacterial membranes and are less susceptible to the development of resistance in bacteria.

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Maruthapandi, Moorthy, Arumugam Saravanan, Akanksha Gupta, John H. T. Luong, and Aharon Gedanken. "Antimicrobial Activities of Conducting Polymers and Their Composites." Macromol 2, no. 1 (February 9, 2022): 78–99. http://dx.doi.org/10.3390/macromol2010005.

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Conducting polymers, mainly polyaniline (PANI) and polypyrrole (PPY) with positive charges bind to the negatively charged bacterial membrane to interfere with bacterial activities. After this initial electrostatic adherence, the conducting polymers might partially penetrate the bacterial membrane and interact with other intracellular biomolecules. Conducting polymers can form polymer composites with metal, metal oxides, and nanoscale carbon materials as a new class of antimicrobial agents with enhanced antimicrobial properties. The accumulation of elevated oxygen reactive species (ROS) from composites of polymers-metal nanoparticles has harmful effects and induces cell death. Among such ROS, the hydroxyl radical with one unpaired electron in the structure is most effective as it can oxidize any bacterial biomolecules, leading to cell death. Future endeavors should focus on the combination of conducting polymers and their composites with antibiotics, small peptides, and natural molecules with antimicrobial properties. Such arsenals with low cytotoxicity are expected to eradicate the ESKAPE pathogens: Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp.

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Sharma, Hemlata, Jyoti Pal, and Deepesh Kumar Neelam. "Bacterial Extracellular Polymers: A Review." Journal of Pure and Applied Microbiology 15, no. 3 (July 17, 2021): 1072–82. http://dx.doi.org/10.22207/jpam.15.3.28.

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Prokaryotic microbial cells especially bacteria are highly emphases for their exopolysaccharides (EPS) production. EPS are the higher molecular weight natural extracellular compounds observe at the surface of the bacterial cells. Nowadays bacterial EPS represent rapidly emerging as new and industrially important biomaterials because it having tremendous physical and chemical properties with novel functionality. Due to its industrial demand as well as research studies the different extraction processes have been discovered to remove the EPS from the microbial biofilm. The novelties of EPS are also based on the microbial habitat conditions such as higher temperature, lower temperature, acidic, alkaliphilic, saline, etc. Based on its chemical structure they can be homopolysaccharide or heteropolysaccharide. EPSs have a wide range of applications in various industries such as food, textile, pharmaceutical, heavy metal recovery, agriculture, etc. So, this review focus on the understanding of the structure, different extraction processes, biosynthesis and genetic engineering of EPS as well as their desirable biotechnological applications.

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TAKAI, Mitsuo, and Tomoki ERATA. "Natural Polymers. Bacterial Cellulose." Kobunshi 47, no. 6 (1998): 382–85. http://dx.doi.org/10.1295/kobunshi.47.382.

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Rojas-Tapias, Daniel, Oriana Ortega Sierra, Diego Rivera Botía, and Ruth Bonilla. "Preservation of Azotobacter chroococcum vegetative cells in dry polymers." Universitas Scientiarum 20, no. 2 (October 10, 2014): 201. http://dx.doi.org/10.11144/javeriana.sc20-2.pacv.

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We studied the preservation of Azotobacter chroococcum C26 using three dry polymers: carrageenin, sodium alginate, and HPMC, using a method of accelerated degradation. Bacterial viability, as response variable, was measured at three temperatures in four different times, which was followed by calculation of bacterial degradation rates. Results showed that temperature, time of storage, and protective agent influenced both viability and degradation rates (P;lt;0.05). We observed, using the Arrhenius thermodynamic model, that the use of polymers increased the activation energy of bacterial degradation compared to control. We obtained thermodynamic models for each polymer, based on the Arrhenius equation, which predicted the required time for thermal degradation of the cells at different temperatures. Analysis of the models showed that carrageenin was the best polymer to preserve A. chroococcum C26 since ~ 900 days are required at 4 ºC to reduce its viability in two log units. We conclude, therefore, that long-term preservation of A. chroococcum C26 using dry polymers is suitable under adequate preservation and storage conditions.

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Schäffer, Christina, and Paul Messner. "The structure of secondary cell wall polymers: how Gram-positive bacteria stick their cell walls together." Microbiology 151, no. 3 (March 1, 2005): 643–51. http://dx.doi.org/10.1099/mic.0.27749-0.

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The cell wall of Gram-positive bacteria has been a subject of detailed chemical study over the past five decades. Outside the cytoplasmic membrane of these organisms the fundamental polymer is peptidoglycan (PG), which is responsible for the maintenance of cell shape and osmotic stability. In addition, typical essential cell wall polymers such as teichoic or teichuronic acids are linked to some of the peptidoglycan chains. In this review these compounds are considered as ‘classical’ cell wall polymers. In the course of recent investigations of bacterial cell surface layers (S-layers) a different class of ‘non-classical’ secondary cell wall polymers (SCWPs) has been identified, which is involved in anchoring of S-layers to the bacterial cell surface. Comparative analyses have shown considerable differences in chemical composition, overall structure and charge behaviour of these SCWPs. This review discusses the progress that has been made in understanding the structural principles of SCWPs, which may have useful applications in S-layer-based ‘supramolecular construction kits' in nanobiotechnology.

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Ohgita, Takashi, Naoki Hayashi, Naomasa Gotoh, and Kentaro Kogure. "Suppression of type III effector secretion by polymers." Open Biology 3, no. 12 (December 2013): 130133. http://dx.doi.org/10.1098/rsob.130133.

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Bacteria secrete effector proteins required for successful infection and expression of toxicity into host cells. The type III secretion apparatus is involved in these processes. Previously, we showed that the viscous polymer polyethylene glycol (PEG) 8000 suppressed effector secretion by Pseudomonas aeruginosa . We thus considered that other viscous polymers might also suppress secretion. We initially showed that PEG200 (formed from the same monomer (ethylene glycol) as PEG8000, but which forms solutions of lower viscosity than the latter compound) did not decrease effector secretion. By contrast, alginate, a high-viscous polymer formed from mannuronic and guluronic acid, unlike PEG8000, effectively inhibited secretion. The effectiveness of PEG8000 and alginate in this regard was closely associated with polymer viscosity, but the nature of viscosity dependence differed between the two polymers. Moreover, not only the natural polymer alginate, but also mucin, which protects against infection, suppressed secretion. We thus confirmed that polymer viscosity contributes to the suppression of effector secretion, but other factors (e.g. electrostatic interaction) may also be involved. Moreover, the results suggest that regulation of bacterial secretion by polymers may occur naturally via the action of components of biofilm or mucin layer.

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van Tol, Eric A. F., Lisa Holt, Feng Ling Li, Feng-Ming Kong, Richard Rippe, Mitsuo Yamauchi, Jolanta Pucilowska, P. Kay Lund, and R. Balfour Sartor. "Bacterial cell wall polymers promote intestinal fibrosis by direct stimulation of myofibroblasts." American Journal of Physiology-Gastrointestinal and Liver Physiology 277, no. 1 (July 1, 1999): G245—G255. http://dx.doi.org/10.1152/ajpgi.1999.277.1.g245.

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Normal luminal bacteria and bacterial cell wall polymers are implicated in the pathogenesis of chronic intestinal inflammation. To determine the direct involvement of bacteria and their products on intestinal fibrogenesis, the effects of purified bacterial cell wall polymers on collagen and cytokine synthesis were evaluated in intestinal myofibroblast cultures established from normal fetal and chronically inflamed cecal tissues. In this study, the intestines of Lewis rats were intramurally injected with peptidoglycan-polysaccharide polymers. Collagen and transforming growth factor (TGF)-β1 mRNA levels were measured and correlated with mesenchymal cell accumulation by immunohistochemistry. The direct effects of cell wall polymers on fibrogenic cytokine and collagen α1 (type I) expression were evaluated in intestinal myofibroblast cultures. We found that intramural injections of bacterial cell wall polymers induced chronic granulomatous enterocolitis with markedly increased collagen synthesis and concomitant increased TGF-β1 and interleukin (IL)-6 expression. Intestinal myofibroblast cultures were established, which both phenotypically and functionally resemble the mesenchymal cells that are involved in fibrosis in vivo. Bacterial cell wall polymers directly stimulated collagen α1 (I), TGF-β1, IL-1β, and IL-6 mRNA expression in the intestinal myofibroblasts derived from both normal and inflamed cecum. Neutralization of endogenous TGF-β1 inhibited in vitro collagen gene expression. From our results, we conclude that increased exposure to luminal bacterial products can directly activate intestinal mesenchymal cells, which accumulate in areas of chronic intestinal inflammation, thus stimulating intestinal fibrosis in genetically susceptible hosts.

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Hansen, Niko, Adriana Bryant, Roslyn McCormack, Hannah Johnson, Travis Lindsay, Kael Stelck, and Matthew T. Bernards. "Assessment of the performance of nonfouling polymer hydrogels utilizing citizen scientists." PLOS ONE 16, no. 12 (December 31, 2021): e0261817. http://dx.doi.org/10.1371/journal.pone.0261817.

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To facilitate longer duration space travel, flight crew sickness and disease transmission amongst the crew must be eliminated. High contact surfaces within space vehicles provide an opportunity for bacterial adhesion, which can lead to biofilm formation or disease transmission. This study evaluates the performance of several nonfouling polymers using citizen science, to identify the best performing chemistry for future applications as bacteria resistant coatings. The specific polymer chemistries tested were zwitterionic sulfobetaine methacrylate (SBMA), and polyampholytes composed of [2-(acryloyloxy)ethyl] trimethylammonium chloride and 2-carboxyethyl acrylate (TMA/CAA), or TMA and 3-sulfopropyl methacrylate (TMA/SA). Each polymer chemistry is known to exhibit bacteria resistance, and this study provides a direct side-by-side comparison between the chemistries using a citizen science approach. Nearly 100 citizen scientists returned results comparing the performance of these polymers over repeat exposure to bacteria and 30 total days of growth. The results demonstrate that TMA/CAA polyampholyte hydrogels show the best long-term resistance to bacteria adhesion.

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Bosch, Paula, Desislava Staneva, Evgenia Vasileva-Tonkova, Petar Grozdanov, Ivanka Nikolova, Rositsa Kukeva, Radostina Stoyanova, and Ivo Grabchev. "Hyperbranched Polymers Modified with Dansyl Units and Their Cu(II) Complexes. Bioactivity Studies." Materials 13, no. 20 (October 14, 2020): 4574. http://dx.doi.org/10.3390/ma13204574.

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Two new copper complexes of hyperbranched polymers modified with dansyl units were synthesized and characterized by infrared spectroscopy (IR) and electron paramagnetic resonance (EPR) techniques. It was found that copper ions coordinate predominantly with nitrogen or oxygen atoms of the polymer molecule. The place of the formation of complexes and the number of copper ions involved depend on the chemical structure of the polymer. The antimicrobial activity of the new polymers and their Cu(II) complexes was tested against Gram-negative and Gram-positive bacterial and fungal strains. Copper complexes were found to have activity better than that of the corresponding ligands. The deposition of the modified branched polymers onto cotton fabrics prevents the formation of bacterial biofilms, which indicates that the studied polymers can find application in antibacterial textiles.

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Whitfield, Chris. "Bacterial extracellular polysaccharides." Canadian Journal of Microbiology 34, no. 4 (April 1, 1988): 415–20. http://dx.doi.org/10.1139/m88-073.

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The synthesis of extracellular polysaccharides has been recognized in certain bacterial cultures since the 1880s. It is now apparent that a wide range of bacteria produce these polymers and an equally wide range of chemical structures are possible. Their surface location, together with the range of available monosaccharide combinations, noncarbohydrate substituents, and linkage types, make extracellular polysaccharides excellent agents of diversity. As a result, much effort has been directed towards elucidating their structure in pathogenic bacteria and in enteric organisms in particular. Commercial applications of microbial polysaccharides have now broadened the scope of structural information. Most recently, technological advances in molecular biology have created the possibility of manipulating desired polymer characteristics, and with these advances, our knowledge of the mechanisms of synthesis and regulation of cell surface polysaccharides has improved. Ultimately more information regarding the function of extracellular polysaccharides in natural environments may result.

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Meng, En, Chin-Li Chen, Chuan-Chieh Liu, Cheng-Che Liu, Shu-Jen Chang, Juin-Hong Cherng, Hsiao-Hsien Wang, and Sheng-Tang Wu. "Bioapplications of Bacterial Cellulose Polymers Conjugated with Resveratrol for Epithelial Defect Regeneration." Polymers 11, no. 6 (June 15, 2019): 1048. http://dx.doi.org/10.3390/polym11061048.

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Excellent wound dressing is essential for effective wound repair and regeneration. However, natural polymeric skin substitutes often lack mechanical strength and hydrophilicity. One way to overcome this limitation is to use biodegradable polymers with high mechanical strength and low skin-irritation induction in wet environments. Bacterial cellulose (BC) is an attractive polymer for medical applications; unlike synthetic polymers, it is biodegradable and renewable and has a strong affinity for materials containing hydroxyl groups. Therefore, we conjugated it with resveratrol (RSV), which has a 4′-hydroxyl group and exhibits good biocompatibility and no cytotoxicity. We synthesized BC scaffolds with immobilized RSV and characterized the resulting BC/RSV scaffold with scanning electron microscopy and Fourier-transform infrared spectroscopy. We found that RSV was released from the BC in vitro after ~10 min, and immunofluorescence staining showed that BC was highly biocompatible and regenerated epithelia. Additionally, Masson’s trichrome staining showed that the scaffolds preserved the normal collagen-bundling pattern and induced re-epithelialization in defective rat epidermis. These results indicated that RSV-conjugated BC created a biocompatible environment for stem cell attachment and growth and promoted epithelial regeneration during wound healing.

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Montdargent, Béatrice, and Didier Letourneur. "Toward New Biomaterials." Infection Control & Hospital Epidemiology 21, no. 6 (June 2000): 404–10. http://dx.doi.org/10.1086/501782.

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Polymers are widely used for a large range of medical devices used as biomaterials on a temporary, intermittent, and long-term basis. It is now well accepted that the initial rapid adsorption of proteins to polymeric surfaces affects the performance of these biomaterials. However, protein adsorption to a polymer surface can be modulated by an appropriate design of the interface. Extensive study has shown that these interactions can be minimized by coating with a highly hydrated layer (hydrogel), by grafting on the surface different biomolecules, or by creating domains with chemical functions (charges, hydrophilic groups). Our laboratory has investigated the latter approach over the past 2 decades, in particular the synthesis and the biological activities of polymers to improve the biocompatibility of blood-contacting devices. These soluble and insoluble polymers were obtained by chemical substitution of macromolecular chains with suitable groups able to develop specific interactions with biological components. Applied to compatibility with the blood and the immune systems, this concept has been extended to interactions of polymeric biomaterials with eukaryotic and prokaryotic cells. The design of new biomaterials with low bacterial attachment is thus under intensive study. After a brief overview of current trends in the surface modifications of biocompatible materials, we will describe how biospecific polymers can be obtained and review our recent results on the inhibition of bacterial adhesion using one type of functionalized polymer obtained by random substitution. This strategy, applied to existing or new materials, seems promising for the limitation of biomaterial-associated infections.

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Kroiča, Juta, Ingus Skadiņš, Ilze Salma, Aigars Reinis, Marina Sokolova, Dagnija Rostoka, and Natālija Bērza. "Antibacterial Efficiency of Hydroxyapatite Biomaterials with Biodegradable Polylactic Acid and Polycaprolactone Polymers Saturated with Antibiotics / Bionoārdāmu Polimēru Saturošu Un Ar Antibiotiskajām Vielām Piesūcinātu Biomateriālu Antibakteriālās Efektivitātes Noteikšana." Proceedings of the Latvian Academy of Sciences. Section B. Natural, Exact, and Applied Sciences. 70, no. 4 (August 1, 2016): 220–26. http://dx.doi.org/10.1515/prolas-2016-0035.

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Abstract Infections continue to spread in all fields of medicine, and especially in the field of implant biomaterial surgery, and not only during the surgery, but also after surgery. Reducing the adhesion of bacteria could decrease the possibility of biomaterial-associated infections. Bacterial adhesion could be reduced by local antibiotic release from the biomaterial. In this in vitro study, hydroxyapatite biomaterials with antibiotics and biodegradable polymers were tested for their ability to reduce bacteria adhesion and biofilm development. This study examined the antibacterial efficiency of hydroxyapatite biomaterials with antibiotics and biodegradable polymers against Staphylococcus epidermidis and Pseudomonas aeruginosa. The study found that hydroxyapatite biomaterials with antibiotics and biodegradable polymers show longer antibacterial properties than hydroxyapatite biomaterials with antibiotics against both bacterial cultures. Therefore, the results of this study demonstrated that biomaterials that are coated with biodegradable polymers release antibiotics from biomaterial samples for a longer period of time and may be useful for reducing bacterial adhesion on orthopedic implants.

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Schulze, Holger, Harry Wilson, Ines Cara, Steven Carter, Edward N. Dyson, Ravikrishnan Elangovan, Stephen Rimmer, and Till T. Bachmann. "Label-Free Electrochemical Sensor for Rapid Bacterial Pathogen Detection Using Vancomycin-Modified Highly Branched Polymers." Sensors 21, no. 5 (March 8, 2021): 1872. http://dx.doi.org/10.3390/s21051872.

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Rapid point of care tests for bacterial infection diagnosis are of great importance to reduce the misuse of antibiotics and burden of antimicrobial resistance. Here, we have successfully combined a new class of non-biological binder molecules with electrochemical impedance spectroscopy (EIS)-based sensor detection for direct, label-free detection of Gram-positive bacteria making use of the specific coil-to-globule conformation change of the vancomycin-modified highly branched polymers immobilized on the surface of gold screen-printed electrodes upon binding to Gram-positive bacteria. Staphylococcus carnosus was detected after just 20 min incubation of the sample solution with the polymer-functionalized electrodes. The polymer conformation change was quantified with two simple 1 min EIS tests before and after incubation with the sample. Tests revealed a concentration dependent signal change within an OD600 range of Staphylococcus carnosus from 0.002 to 0.1 and a clear discrimination between Gram-positive Staphylococcus carnosus and Gram-negative Escherichia coli bacteria. This exhibits a clear advancement in terms of simplified test complexity compared to existing bacteria detection tests. In addition, the polymer-functionalized electrodes showed good storage and operational stability.

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Wang, Yin, and Hui Sun. "Polymeric Nanomaterials for Efficient Delivery of Antimicrobial Agents." Pharmaceutics 13, no. 12 (December 7, 2021): 2108. http://dx.doi.org/10.3390/pharmaceutics13122108.

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Bacterial infections have threatened the lives of human beings for thousands of years either as major diseases or complications. The elimination of bacterial infections has always occupied a pivotal position in our history. For a long period of time, people were devoted to finding natural antimicrobial agents such as antimicrobial peptides (AMPs), antibiotics and silver ions or synthetic active antimicrobial substances including antimicrobial peptoids, metal oxides and polymers to combat bacterial infections. However, with the emergence of multidrug resistance (MDR), bacterial infection has become one of the most urgent problems worldwide. The efficient delivery of antimicrobial agents to the site of infection precisely is a promising strategy for reducing bacterial resistance. Polymeric nanomaterials have been widely studied as carriers for constructing antimicrobial agent delivery systems and have shown advantages including high biocompatibility, sustained release, targeting and improved bioavailability. In this review, we will highlight recent advances in highly efficient delivery of antimicrobial agents by polymeric nanomaterials such as micelles, vesicles, dendrimers, nanogels, nanofibers and so forth. The biomedical applications of polymeric nanomaterial-based delivery systems in combating MDR bacteria, anti-biofilms, wound healing, tissue engineering and anticancer are demonstrated. Moreover, conclusions and future perspectives are also proposed.

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Andoy, Nesha May Octavio, Meera Patel, Ching Lam Jane Lui, and Ruby May Arana Sullan. "Immobilization of Polyethyleneimine (PEI) on Flat Surfaces and Nanoparticles Affects Its Ability to Disrupt Bacterial Membranes." Microorganisms 9, no. 10 (October 19, 2021): 2176. http://dx.doi.org/10.3390/microorganisms9102176.

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Interactions between a widely used polycationic polymer, polyethyleneimine (PEI), and a Gram-negative bacteria, E. coli, are investigated using atomic force microscopy (AFM) quantitative imaging. The effect of PEI, a known membrane permeabilizer, is characterized by probing both the structure and elasticity of the bacterial cell envelope. At low concentrations, PEI induced nanoscale membrane perturbations all over the bacterial surface. Despite these structural changes, no change in cellular mechanics (Young’s modulus) was detected and the growth of E. coli is barely affected. However, at high PEI concentrations, dramatic changes in both structure and cell mechanics are observed. When immobilized on a flat surface, the ability of PEI to alter the membrane structure and reduce bacterial elasticity is diminished. We further probe this immobilization-induced effect by covalently attaching the polymer to the surface of polydopamine nanoparticles (PDNP). The nanoparticle-immobilized PEI (PDNP-PEI), though not able to induce major structural changes on the outer membrane of E. coli (in contrast to the flat surface), was able to bind to and reduce the Young’s modulus of the bacteria. Taken together, our data demonstrate that the state of polycationic polymers, whether bound or free—which greatly dictates their overall configuration—plays a major role on how they interact with and disrupt bacterial membranes.

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Aksoyoglu, M. Alphan, Rudolf Podgornik, Sergey M. Bezrukov, Philip A. Gurnev, Murugappan Muthukumar, and V. Adrian Parsegian. "Size-dependent forced PEG partitioning into channels: VDAC, OmpC, and α-hemolysin." Proceedings of the National Academy of Sciences 113, no. 32 (July 27, 2016): 9003–8. http://dx.doi.org/10.1073/pnas.1602716113.

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Nonideal polymer mixtures of PEGs of different molecular weights partition differently into nanosize protein channels. Here, we assess the validity of the recently proposed theoretical approach of forced partitioning for three structurally different β-barrel channels: voltage-dependent anion channel from outer mitochondrial membrane VDAC, bacterial porin OmpC (outer membrane protein C), and bacterial channel-forming toxin α-hemolysin. Our interpretation is based on the idea that relatively less-penetrating polymers push the more easily penetrating ones into nanosize channels in excess of their bath concentration. Comparison of the theory with experiments is excellent for VDAC. Polymer partitioning data for the other two channels are consistent with theory if additional assumptions regarding the energy penalty of pore penetration are included. The obtained results demonstrate that the general concept of “polymers pushing polymers” is helpful in understanding and quantification of concrete examples of size-dependent forced partitioning of polymers into protein nanopores.

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Noureddine, Mahmoudi. "Study of composite-based natural fibers and renewable polymers, using bacteria to ameliorate the fiber/matrix interface." Journal of Composite Materials 53, no. 4 (July 2, 2018): 455–61. http://dx.doi.org/10.1177/0021998318785965.

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In this paper, bacteria belonging to the species Acetobacter xylinum were used to modify the surface of natural fibers by depositing nanosized bacterial cellulose around natural fibers which enhances their adhesion to renewable polymers. Single fiber tensile test was used in order to determine their mechanical properties and surface. The practical adhesion between the modified fibers and the renewable polymers cellulose acetate butyrate is quantified using the single fiber pullout test. Simple weight gain measurements before and after the modification show that about 4 and 6% bacterial cellulose adheres to the fibers as a result of the bacterial modification procedure. Scanning electron microscopy micrographs confirm the presence of attached bacterial cellulose on the surfaces of natural fibers.

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Schertzer, Jeffrey W., and Eric D. Brown. "Use of CDP-Glycerol as an Alternate Acceptor for the Teichoic Acid Polymerase Reveals that Membrane Association Regulates Polymer Length." Journal of Bacteriology 190, no. 21 (August 19, 2008): 6940–47. http://dx.doi.org/10.1128/jb.00851-08.

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ABSTRACT The study of bacterial extracellular polysaccharide biosynthesis is hampered by the fact that these molecules are synthesized on membrane-resident carrier lipids. To get around this problem, a practical solution has been to synthesize soluble lipid analogs and study the biosynthetic enzymes using a soluble system. This has been done for the Bacillus subtilis teichoic acid polymerase, TagF, although several aspects of catalysis were inconsistent with the results obtained with reconstituted membrane systems or physiological observations. In this work we explored the acceptor substrate promiscuity and polymer length disregulation that appear to be characteristic of TagF activity away from biological membranes. Using isotope labeling, steady-state kinetics, and chemical lability studies, we demonstrated that the enzyme can synthesize poly(glycerol phosphate) teichoic acid using the elongation substrate CDP-glycerol as an acceptor. This suggests that substrate specificity is relaxed in the region distal to the glycerol phosphate moiety in the acceptor molecule under these conditions. Polymer synthesis proceeded at a rate (27 min−1) comparable to that in the reconstituted membrane system after a distinct lag period which likely represented slower initiation on the unnatural CDP-glycerol acceptor. We confirmed that polymer length became disregulated in the soluble system as the polymers synthesized on CDP-glycerol acceptors were much larger than the polymers synthesized on the membrane or previously found attached to bacterial cell walls. Finally, polymer synthesis on protease-treated membranes suggested that proper length regulation is retained in the absence of accessory proteins and provided evidence that such regulation is conferred through proper association of the polymerase with the membrane.

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Wang, Tingting, Lei Xu, Huiying Shen, Xiuming Cao, Qufu Wei, Reza A. Ghiladi, and Qingqing Wang. "Photoinactivation of bacteria by hypocrellin-grafted bacterial cellulose." Cellulose 27, no. 2 (November 11, 2019): 991–1007. http://dx.doi.org/10.1007/s10570-019-02852-9.

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Wenzel, Michaela, Ilkay N. Celik Gulsoy, Yongqiang Gao, Zihao Teng, Joost Willemse, Martijn Middelkamp, Mariska G. M. van Rosmalen, et al. "Control of septum thickness by the curvature of SepF polymers." Proceedings of the National Academy of Sciences 118, no. 2 (December 21, 2020): e2002635118. http://dx.doi.org/10.1073/pnas.2002635118.

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Gram-positive bacteria divide by forming a thick cross wall. How the thickness of this septal wall is controlled is unknown. In this type of bacteria, the key cell division protein FtsZ is anchored to the cell membrane by two proteins, FtsA and/or SepF. We have isolated SepF homologs from different bacterial species and found that they all polymerize into large protein rings with diameters varying from 19 to 44 nm. Interestingly, these values correlated well with the thickness of their septa. To test whether ring diameter determines septal thickness, we tried to construct different SepF chimeras with the purpose to manipulate the diameter of the SepF protein ring. This was indeed possible and confirmed that the conserved core domain of SepF regulates ring diameter. Importantly, when SepF chimeras with different diameters were expressed in the bacterial hostBacillus subtilis, the thickness of its septa changed accordingly. These results strongly support a model in which septal thickness is controlled by curved molecular clamps formed by SepF polymers attached to the leading edge of nascent septa. This also implies that the intrinsic shape of a protein polymer can function as a mold to shape the cell wall.

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Rong, Fan, Yizhang Tang, Tengjiao Wang, Tao Feng, Jiang Song, Peng Li, and Wei Huang. "Nitric Oxide-Releasing Polymeric Materials for Antimicrobial Applications: A Review." Antioxidants 8, no. 11 (November 15, 2019): 556. http://dx.doi.org/10.3390/antiox8110556.

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Polymeric materials releasing nitric oxide have attracted significant attention for therapeutic use in recent years. As one of the gaseous signaling agents in eukaryotic cells, endogenously generated nitric oxide (NO) is also capable of regulating the behavior of bacteria as well as biofilm formation in many metabolic pathways. To overcome the drawbacks caused by the radical nature of NO, synthetic or natural polymers bearing NO releasing moiety have been prepared as nano-sized materials, coatings, and hydrogels. To successfully design these materials, the amount of NO released within a certain duration, the targeted pathogens and the trigger mechanisms upon external stimulation with light, temperature, and chemicals should be taken into consideration. Meanwhile, NO donors like S-nitrosothiols (RSNOs) and N-diazeniumdiolates (NONOates) have been widely utilized for developing antimicrobial polymeric agents through polymer-NO donor conjugation or physical encapsulation. In addition, antimicrobial materials with visible light responsive NO donor are also reported as strong and physiological friendly tools for rapid bacterial clearance. This review highlights approaches to delivery NO from different types of polymeric materials for combating diseases caused by pathogenic bacteria, which hopefully can inspire researchers facing common challenges in the coming ‘post-antibiotic’ era.

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Leong, Jiayu, Chuan Yang, Jason Tan, Bing Qian Tan, Sherwin Hor, James L. Hedrick, and Yi Yan Yang. "Combination of guanidinium and quaternary ammonium polymers with distinctive antimicrobial mechanisms achieving a synergistic antimicrobial effect." Biomaterials Science 8, no. 24 (2020): 6920–29. http://dx.doi.org/10.1039/d0bm00752h.

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Bonenfant, Danielle, François-René Bourgeois, Murielle Mimeault, Frédéric Monette, Patrick Niquette, and Robert Hausler. "Synthesis and structure-activity study of quaternary ammonium functionalized β-cyclodextrin-carboxymethylcellulose polymers." Water Science and Technology 63, no. 12 (June 1, 2011): 2827–32. http://dx.doi.org/10.2166/wst.2011.630.

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Carboxymethylcellulose (CMC) and β-cyclodextrin (β-CD)-based polymers functionalized with two types of quaternary ammonium compounds (QACs), the alkaquat DMB-451 (N-alkyl (50% C14, 40% C12, 10% C10) dimethylbenzylammonium chloride) (DMD-451) named polymer DMB-451, and FMB 1210-8 (a blend of 32 w% N-alkyl (50% C14, 40% C12, 10% C10) dimethylbenzylammonium chloride and 48 w% of didecyldimethylammonium chloride) named polymer FMB 1210-8, were synthethized and characterized by Fourier transform infrared spectroscopy. The antimicrobial activities of these polymers against Eschericia coli were also evaluated at 25 °C in wastewater. The results have indicated that the polymer FMB 1210-8 possesses a high-affinity binding with bacterial cells that induces a rapid disinfection process. Moreover, in the same experimental conditions of disinfection (mixture of 1.0 g of polymer and 100 mL of wastewater), the polymer FMB 1210-8 has a higher antimicrobial efficiency (99.90%) than polymer DMB-451 (92.8%). This phenomenon might be associated to a stronger interaction with bacterial cells due to stronger binding affinity for E. coli cells and greater killing efficiency of the C10 alkyl chains QAC of polymer FMB 1210-8 to disrupt the bacterial cell membrane as compared to N-alkyl (50% C14, 40% C12, 10% C10) dimethylbenzylammonium chloride. Together, these results suggest that the polymer FMB 1210-8 could constitute a good disinfectant against Escherichia coli, which could be advantageously used in wastewater treatments due to the low toxicity of β-CD and CMC, and moderated toxicity of FMB 1210-8 to human and environment.

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Barbero, Cesar Alfredo, and Diego Fernando Acevedo. "Manufacturing Functional Polymer Surfaces by Direct Laser Interference Patterning (DLIP): A Polymer Science View." Nanomanufacturing 2, no. 4 (November 29, 2022): 229–64. http://dx.doi.org/10.3390/nanomanufacturing2040015.

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Direct laser interference patterning (DLIP) involves the formation of patterns of light intensity using coherent laser light beams that interfere between them. Light on the ultraviolet (<350 nm) and NIR (800–2000 nm) is absorbed in chromophores present in the polymer structure or in loaded absorbing species (dyes, polymers, nanoparticles). The absorbed light induces photothermal/photochemical processes, which alter permanently the topography of the polymer surface. The success of DLIP at different wavelengths is discussed in relation to the optical/thermal properties of the polymers and previous data on laser ablation of polymers. The size of the pattern is related directly to the wavelength of the light and inversely to the sine of the angle between beams and the refractive index of the external medium. In that way, nanometric structures (<100 nm) could be produced. Since the patterning occurs in a single short pulse (<10 ns), large surfaces can be modified. Both bacterial biofilm inhibition and human cell differentiation/orientation have been achieved. Large improvements in technological devices (e.g., thin film solar cells) using DLIP structured surfaces have also been demonstrated. Prospective application of DLIP to common polymers (e.g., Teflon®) and complex polymeric systems (e.g., layer-by-layer multilayers) is discussed on the basis of reported polymer data.

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Doi, Yoshiharu. "Microbial Synthesis and Properties of Polyhydroxy-alkanoates." MRS Bulletin 17, no. 11 (November 1992): 39–42. http://dx.doi.org/10.1557/s0883769400046649.

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A wide variety of microorganisms accumulate an optically active polymer of D(−)-3-hydroxybutyric acid, P(3HB), as an intracellular storage material of carbon and energy. The P(3HB) was first isolated from Bacillus megaterium in 1925 by Lemoigne. Many prokaryotic organisms, such as bacteria and cyanobacteria, have been found to accumulate P(3HB) up to 80% of their cellular dry weight when growth is limited by the depletion of an essential nutrient such as nitrogen, oxygen, phosphorus, or magnesium. Recently, many bacteria have been found to accumulate copolymers of D(−)3-hydroxy-alkanoic acids with a chain length ranging from three to 14 carbon atoms. In addition, 4-hydroxybutyric acid was found as a constituent of bacterial polyhy-droxyalkanoates (PHA).Bacterial PHA polymers have attracted much attention as environmentally degradable thermoplastics for a wide range of agricultural, marine, and medical applications. PHA is degraded in soil, sludge, or sea water. Some microorganisms such as bacteria and fungi secrete extracellular PHA depolymerases to degrade environmental PHA and utilize the decomposed compounds as nutrients. In this article, I report the metabolism, production, and properties of bacterial PHA.

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Šerá, Jana, Florence Huynh, Faith Ly, Štěpán Vinter, Markéta Kadlečková, Vendula Krátká, Daniela Máčalová, Marek Koutný, and Christopher Wallis. "Biodegradable Polyesters and Low Molecular Weight Polyethylene in Soil: Interrelations of Material Properties, Soil Organic Matter Substances, and Microbial Community." International Journal of Molecular Sciences 23, no. 24 (December 15, 2022): 15976. http://dx.doi.org/10.3390/ijms232415976.

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Conventional and also biodegradable polymer microplastics have started to be broadly present in the environment, if they end up in soil, they may influence both abiotic and biotic soil properties. In this study, the interactions of polyethylene wax together with three biodegradable polyesters PLA, PHB and PBAT with a soil matrix were investigated over a 1-year incubation period. Soil organic matter content was measured using UV–VIS, the microbial biomass amount was measured using qPCR, the mineralisation of polymers was measured using UGA 3000, the surface of polymers was observed with SEM, live/dead microorganisms were determined by fluorescent microscopy and microbial consortia diversity was analyzed using NGS. The amount of humic substances was generally higher in incubations with slowly degrading polyesters, but the effect was temporary. The microbial biomass grew during the incubations; the addition of PHB enhanced fungal biomass whereas PE wax enhanced bacterial biomass. Fungal microbial consortia diversity was altered in incubations with PHB and PBAT. Interestingly, these two polyesters were also covered in biofilm, probably fungal. No such trend was observed in a metagenomic analysis of bacteria, although, bacterial biofilm was probably formed on the PE520 surface. Different methods confirmed the effect of certain polymers on the soil environment.

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Armentano, Ilaria, Carla Renata Arciola, Elena Fortunati, Davide Ferrari, Samantha Mattioli, Concetta Floriana Amoroso, Jessica Rizzo, Jose M. Kenny, Marcello Imbriani, and Livia Visai. "The Interaction of Bacteria with Engineered Nanostructured Polymeric Materials: A Review." Scientific World Journal 2014 (2014): 1–18. http://dx.doi.org/10.1155/2014/410423.

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Bacterial infections are a leading cause of morbidity and mortality worldwide. In spite of great advances in biomaterials research and development, a significant proportion of medical devices undergo bacterial colonization and become the target of an implant-related infection. We present a review of the two major classes of antibacterial nanostructured materials: polymeric nanocomposites and surface-engineered materials. The paper describes antibacterial effects due to the induced material properties, along with the principles of bacterial adhesion and the biofilm formation process. Methods for antimicrobial modifications of polymers using a nanocomposite approach as well as surface modification procedures are surveyed and discussed, followed by a concise examination of techniques used in estimating bacteria/material interactions. Finally, we present an outline of future sceneries and perspectives on antibacterial applications of nanostructured materials to resist or counteract implant infections.

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Foster, Leanna L., Shin-ichi Yusa, and Kenichi Kuroda. "Solution-Mediated Modulation of Pseudomonas aeruginosa Biofilm Formation by a Cationic Synthetic Polymer." Antibiotics 8, no. 2 (May 10, 2019): 61. http://dx.doi.org/10.3390/antibiotics8020061.

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Bacterial biofilms and their associated infections are a continuing problem in the healthcare community. Previous approaches utilizing anti-biofilm coatings suffer from short lifetimes, and their applications are limited to surfaces. In this research, we explored a new approach to biofilm prevention based on the hypothesis that changing planktonic bacteria behavior to result in sub-optimal biofilm formation. The behavior of planktonic Pseudomonas aeruginosa exposed to a cationic polymer was characterized for changes in growth behavior and aggregation behavior, and linked to resulting P. aeruginosa biofilm formation, biomass, viability, and metabolic activity. The incubation of P. aeruginosa planktonic bacteria with a cationic polymer resulted in the aggregation of planktonic bacteria, and a reduction in biofilm development. We propose that cationic polymers may sequester planktonic bacteria away from surfaces, thereby preventing their attachment and suppressing biofilm formation.

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Rehm, Bernd H. A. "Bacterial polymers: biosynthesis, modifications and applications." Nature Reviews Microbiology 8, no. 8 (June 28, 2010): 578–92. http://dx.doi.org/10.1038/nrmicro2354.

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Golabi, Mohsen, Anthony P. F. Turner, and Edwin W. H. Jager. "Tunable conjugated polymers for bacterial differentiation." Sensors and Actuators B: Chemical 222 (January 2016): 839–48. http://dx.doi.org/10.1016/j.snb.2015.09.033.

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Barton, Alan J., Richard D. Sagers, and William G. Pitt. "Bacterial adhesion to orthopedic implant polymers." Journal of Biomedical Materials Research 30, no. 3 (March 1996): 403–10. http://dx.doi.org/10.1002/(sici)1097-4636(199603)30:3<403::aid-jbm15>3.0.co;2-k.

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Wulandari, Erna, Rachel Budhisatria, Alexander H. Soeriyadi, Mark Willcox, Cyrille Boyer, and Edgar H. H. Wong. "Releasable antimicrobial polymer-silk coatings for combating multidrug-resistant bacteria." Polymer Chemistry 12, no. 48 (2021): 7038–47. http://dx.doi.org/10.1039/d1py01219c.

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Kregiel, Dorota, Anna Rygala, Beata Kolesinska, Maria Nowacka, Agata S. Herc, and Anna Kowalewska. "Antimicrobial and Antibiofilm N-acetyl-L-cysteine Grafted Siloxane Polymers with Potential for Use in Water Systems." International Journal of Molecular Sciences 20, no. 8 (April 24, 2019): 2011. http://dx.doi.org/10.3390/ijms20082011.

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Antibiofilm strategies may be based on the prevention of initial bacterial adhesion, the inhibition of biofilm maturation or biofilm eradication. N-acetyl-L-cysteine (NAC), widely used in medical treatments, offers an interesting approach to biofilm destruction. However, many Eubacteria strains are able to enzymatically decompose the NAC molecule. This is the first report on the action of two hybrid materials, NAC-Si-1 and NAC-Si-2, against bacteria isolated from a water environment: Agrobacterium tumefaciens, Aeromonas hydrophila, Citrobacter freundii, Enterobacter soli, Janthinobacterium lividum and Stenotrophomonas maltophilia. The NAC was grafted onto functional siloxane polymers to reduce its availability to bacterial enzymes. The results confirm the bioactivity of NAC. However, the final effect of its action was environment- and strain-dependent. Moreover, all the tested bacterial strains showed the ability to degrade NAC by various metabolic routes. The NAC polymers were less effective bacterial inhibitors than NAC, but more effective at eradicating mature bacterial biofilms.

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Pan, Yuanfeng, Qiuyang Xia, and Huining Xiao. "Cationic Polymers with Tailored Structures for Rendering Polysaccharide-Based Materials Antimicrobial: An Overview." Polymers 11, no. 8 (August 1, 2019): 1283. http://dx.doi.org/10.3390/polym11081283.

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Antimicrobial polymers have attracted substantial interest due to high demands on improving the health of human beings via reducing the infection caused by various bacteria. The review presented herein focuses on rendering polysaccharides, mainly cellulosic-based materials and starch to some extent, antimicrobial via incorporating cationic polymers, guanidine-based types in particular. Extensive review on synthetic antimicrobial materials or plastic/textile has been given in the past. However, few review reports have been presented on antimicrobial polysaccharide, cellulosic-based materials, or paper packaging, especially. The current review fills the gap between synthetic materials and natural polysaccharides (cellulose, starch, and cyclodextrin) as substrates or functional additives for different applications. Among various antimicrobial polymers, particular attention in this review is paid to guanidine-based polymers and their derivatives, including copolymers, star polymer, and nanoparticles with core-shell structures. The review has also been extended to gemini surfactants and polymers. Cationic polymers with tailored structures can be incorporated into various products via surface grafting, wet-end addition, blending, or reactive extrusion, effectively addressing the dilemma of improving substrate properties and bacterial growth. Moreover, the pre-commercial trial conducted successfully for making antimicrobial paper packaging has also been addressed.

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López-Fernández, Ana M., Ignacio Muñoz Resta, Rosa de Llanos, and Francisco Galindo. "Photodynamic Inactivation of Pseudomonas aeruginosa by PHEMA Films Loaded with Rose Bengal: Potentiation Effect of Potassium Iodide." Polymers 13, no. 14 (July 6, 2021): 2227. http://dx.doi.org/10.3390/polym13142227.

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Four formulations have been used to produce different poly(2-hydroxyethyl methacrylate) (PHEMA) thin films, containing singlet oxygen photosensitizer Rose Bengal (RB). The polymers have been characterized employing Thermogravimetric Analysis (TGA), Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR) and UV-vis Absorption Spectroscopy. When irradiated with white light (400–700 nm) films generated singlet oxygen (1O2), as demonstrated by the reactivity with 1O2 trap 9,10-dimethylanthracene (DMA). Material with the highest RB loading (polymer A4, 835 nmol RB/g polymer) was able to perform up to ten cycles of DMA oxygenation reactions at high conversion rates (ca. 90%). Polymer A4 was also able to produce the complete eradication of a Pseudomonas aeruginosa planktonic suspension of 8 log10 CFU/mL, when irradiated with white light (total dose 72 J/cm2). The antimicrobial photodynamic effect was remarkably enhanced by adding potassium iodide (100 mM). In such conditions the complete bacterial reduction occurred with a total light dose of 24 J/cm2. Triiodide anion (I3−) generation was confirmed by UV-vis absorption spectroscopy. This species was detected inside the PHEMA films after irradiation and at concentrations ca. 1 M. The generation of this species and its retention in the matrix imparts long-lasting bactericidal effects to the RB@PHEMA polymeric hydrogels. The polymers here described could find potential applications in the medical context, when optimized for their use in everyday objects, helping to prevent bacterial contagion by contact with surfaces.

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Prasad. B, Venkata Nagendra, and Latha D. "Investigating the Synergistic Antibacterial Activity of Epiphytic Bacterial Polyketides and Biopolymer Alginates from Marine Microalgae." Journal of University of Shanghai for Science and Technology 23, no. 10 (October 4, 2021): 115–35. http://dx.doi.org/10.51201/jusst/21/09704.

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The objective was framed to analyse the synergistic antibacterial activity and woundhealing ability of the developed polyketide-alginate polymers. Alginates were extracted from a brown seaweed Padina tetrastromatica and used as a synergistic compound along with bacterial polyketides. Polyketides and alginate polymer combinations were used against test bacteria to determine the synergistic antibacterial activity. A novel wound-healing film was developed using polyketide and alginates with synergistic concentrations and its degradability and wound-healing ability was investigated. The findings in the present research showed most significantly that, Staphylococcus aureus showed complete synergy with the mean MIC value of 0.03 μg/ml and with best FIC value of 0.24 (p<0.5). Degradation of developed films revealed that more moisture leads to more release of antibacterial alginate content at the wound site and hence more degradation. This was evident from the FESEM analysis. In vitro wound-healing assay revealed that the developed polyketide-alginate polymers exhibited cell migration and proliferation after 24th hour of incubation at 370C indicating the wound-healing abilities. Hence, it can be concluded that the biochemical compounds present in the developed polyketide-alginate polymers are considered highly significant in treating any types of wounds.

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Goto, Hiromasa. "Polymerisation on Bio-Tissues." International Letters of Chemistry, Physics and Astronomy 68 (July 2016): 18–23. http://dx.doi.org/10.18052/www.scipress.com/ilcpa.68.18.

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Preparation of electro-active polymers having characteristic surface on biological tissue was carried out. Direct polymerisation on biological material with unique structure can be a new method to obtain functional structure with no use of top-down or bottom-up technologies. Polymerisations of pyrrole, aniline, and 3,4-ethylenedioxythiophene (EDOT) were carried out on the bio-tissues. Surface structure of the bio-tissue/conducting polymer composite was observed with optical microscopy. The results of the present study involve demonstration of deposition of conducting polymers on the surface of wood, membrane of egg, fungus, flower, and bacteria in the water medium. This method allows preparation of electro-active composites with ordered structure through combination of structures of biological tissues. Note that electrochemical polymerisation in bacterial electrolyte solution can be a first example to date.

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Goto, Hiromasa. "Polymerisation on Bio-Tissues." International Letters of Chemistry, Physics and Astronomy 68 (July 19, 2016): 18–23. http://dx.doi.org/10.56431/p-50cxcl.

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Preparation of electro-active polymers having characteristic surface on biological tissue was carried out. Direct polymerisation on biological material with unique structure can be a new method to obtain functional structure with no use of top-down or bottom-up technologies. Polymerisations of pyrrole, aniline, and 3,4-ethylenedioxythiophene (EDOT) were carried out on the bio-tissues. Surface structure of the bio-tissue/conducting polymer composite was observed with optical microscopy. The results of the present study involve demonstration of deposition of conducting polymers on the surface of wood, membrane of egg, fungus, flower, and bacteria in the water medium. This method allows preparation of electro-active composites with ordered structure through combination of structures of biological tissues. Note that electrochemical polymerisation in bacterial electrolyte solution can be a first example to date.

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EL-KAFAFI, El-Sayed, Sunil MUKHERJEE, Mahmoud EL-SHAMI, Jean-Luc PUTAUX, Maryse A. BLOCK, Isabelle PIGNOT-PAINTRAND, Silva LERBS-MACHE, and Denis FALCONET. "The plastid division proteins, FtsZ1 and FtsZ2, differ in their biochemical properties and sub-plastidial localization." Biochemical Journal 387, no. 3 (April 26, 2005): 669–76. http://dx.doi.org/10.1042/bj20041281.

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Plastid division in higher plants is morphologically similar to bacterial cell division, with a process termed binary fission involving constriction of the envelope membranes. FtsZ proteins involved in bacterial division are also present in higher plants, in which the ftsZ genes belong to two distinct families: ftsZ1 and ftsZ2. However, the roles of the corresponding proteins FtsZ1 and FtsZ2 in plastid division have not been determined. Here we show that the expression of plant FtsZ1 and FtsZ2 in bacteria has different effects on cell division, and that distinct protein domains are involved in the process. We have studied the assembly of purified FtsZ1 and FtsZ2 using a chemical cross-linking approach followed by PAGE and electron microscopy analyses of the resulting polymers. This has revealed that FtsZ1 is capable of forming long rod-shaped polymers and rings similar to the bacterial FtsZ structures, whereas FtsZ2 does not form any organized polymer. Moreover, using purified sub-plastidial fractions, we show that both proteins are present in the stroma, and that a subset of FtsZ2 is tightly bound to the purified envelope membranes. These results indicate that FtsZ2 has a localization pattern distinct from that of FtsZ1, which can be related to distinct properties of the proteins. From the results presented here, we propose a model for the sequential topological localization and functions of green plant FtsZ1 and FtsZ2 in chloroplast division.

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Sienkiewicz, Natalia, and Sylwia Członka. "Natural Additives Improving Polyurethane Antimicrobial Activity." Polymers 14, no. 13 (June 21, 2022): 2533. http://dx.doi.org/10.3390/polym14132533.

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In recent years, there has been a growing interest in using polymers with antibacterial and antifungal properties; therefore, the present review is focused on the effect of natural compounds on the antibacterial and antifungal properties of polyurethane (PUR). This topic is important because materials and objects made with this polymer can be used as antibacterial and antifungal ones in places where hygiene and sterile conditions are particularly required (e.g., in healthcare, construction industries, cosmetology, pharmacology, or food industries) and thus can become another possibility in comparison to commonly used disinfectants, which mostly show high toxicity to the environment and the human health. The review presents the possibilities of using natural extracts as antibacterial, antifungal, and antiviral additives, which, in contrast to the currently used antibiotics, have a much wider effect. Antibiotics fight bacterial infections by killing bacteria (bactericidal effect) or slowing and stopping their growth (bacteriostatic effect) and effect on different kinds of fungi, but they do not fight viruses; therefore, compounds of natural origin can find wide use as biocidal substances. Fungi grow in almost any environment, and they reproduce easily in dirt and wet spaces; thus, the development of antifungal PUR foams is focused on avoiding fungal infections and inhibiting growth. Polymers are susceptible to microorganism adhesion and, consequently, are treated and modified to inhibit fungal and bacterial growth. The ability of micro-organisms to grow on polyurethanes can cause human health problems during the use and storage of polymers, making it necessary to use additives that eliminate bacteria, viruses, and fungi.

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Carpa, Rahela, Anca Butiuc-Keul, Iulia Lupan, Lucian Barbu-Tudoran, Vasile Muntean, and Cristina Dobrotă. "Poly-β-hydroxybutyrate accumulation in bacterial consortia from different environments." Canadian Journal of Microbiology 58, no. 5 (May 2012): 660–67. http://dx.doi.org/10.1139/w2012-037.

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The aim of the present study was to examine soil samples from various vegetation zones in terms of physicochemical properties, microbial communities, and isolation and identification (by polymerase chain reaction and transmission electron microscopy) of bacteria producing poly-β-hydroxybutyrates (PHBs). Soil samples were analysed originating from zones with heterogeneous environmental conditions from the Romanian Carpathian Mountains (mountain zone with alpine meadow, karstic zone with limestone meadow, hill zone with xerophilous meadow, and flood plain zone with hygrophilic meadow). Different bacterial groups involved in the nitrogen cycle (aerobic mesophilic heterotrophs, ammonifiers, denitrifiers, nitrifiers, and free nitrogen-fixing bacteria from Azotobacter genus) were analysed. Soil biological quality was assessed by the bacterial indicator of soil quality, which varied between 4.3 and 4.7. A colony polymerase chain reaction technique was used for screening PHB producers. With different primers, specific bands were obtained in all the soil samples. Some wild types of Azotobacter species were isolated from the 4 studied sites. Biodegradable polymers of PHB were assessed by negative staining in transmission electron microscopy. The maximum PHB granules density was obtained in the strains isolated from the xerophilous meadow (10–18 granules/cell), which was the most stressful environment from all the studied sites, as the physicochemical and microbiological tests proved.

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Fletcher, Madilyn, Jeannine M. Lessmann, and George I. Loeb. "Bacterial surface adhesives and biofilm matrix polymers of marine and freshwater bacteria†." Biofouling 4, no. 1-3 (August 1991): 129–40. http://dx.doi.org/10.1080/08927019109378203.

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Journal articles on the topic 'Bacterial polymers'

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