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Littérature scientifique sur le sujet « Bacterial genetics »

Auteur : Grafiati

Publié le 4 juin 2021

Mis à jour le 1 août 2024

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Articles de revues sur le sujet "Bacterial genetics"

Dionisio, Francisco, Ivan Matic, Miroslav Radman, Olivia R. Rodrigues et François Taddei. « Plasmids Spread Very Fast in Heterogeneous Bacterial Communities ». Genetics 162, n^o 4 (1 décembre 2002) : 1525–32. http://dx.doi.org/10.1093/genetics/162.4.1525.

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Abstract Conjugative plasmids can mediate gene transfer between bacterial taxa in diverse environments. The ability to donate the F-type conjugative plasmid R1 greatly varies among enteric bacteria due to the interaction of the system that represses sex-pili formations (products of finOP) of plasmids already harbored by a bacterial strain with those of the R1 plasmid. The presence of efficient donors in heterogeneous bacterial populations can accelerate plasmid transfer and can spread by several orders of magnitude. Such donors allow millions of other bacteria to acquire the plasmid in a matter of days whereas, in the absence of such strains, plasmid dissemination would take years. This “amplification effect” could have an impact on the evolution of bacterial pathogens that exist in heterogeneous bacterial communities because conjugative plasmids can carry virulence or antibiotic-resistance genes.

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Vollmer, Amy Cheng. « Bacterial Genetics ». Developmental Cell 6, n^o 5 (mai 2004) : 617–19. http://dx.doi.org/10.1016/s1534-5807(04)00136-4.

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Breeuwer, J. A., et J. H. Werren. « Cytoplasmic incompatibility and bacterial density in Nasonia vitripennis. » Genetics 135, n^o 2 (1 octobre 1993) : 565–74. http://dx.doi.org/10.1093/genetics/135.2.565.

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Abstract Cytoplasmically (maternally) inherited bacteria that cause reproductive incompatibility between strains are widespread among insects. In the parasitoid wasp Nasonia, incompatibility results in improper condensation and fragmentation of the paternal chromosomes in fertilized eggs. Some form of genome imprinting may be involved. Because of haplodiploidy, incompatibility results in conversion of (diploid) female eggs into (haploid) males. Experiments show that bacterial density is correlated with compatibility differences between male and female Nasonia. Males from strains with high bacterial numbers are incompatible with females from strains with lower numbers. Temporal changes in compatibility of females after tetracycline treatment are generally correlated with decreases in bacterial levels in eggs. However, complete loss of bacteria in mature eggs precedes conversion of eggs to the "asymbiont" compatibility type by 3-4 days. This result is consistent with a critical "imprinting" period during egg maturation, when cytoplasmic bacteria determine compatibility. Consequent inheritance of reduced bacterial numbers in F1 progeny has different effects on compatibility type of subsequent male vs. female progeny. In some cases, partial incompatibility occurs which results in reduced offspring numbers, apparently due to incomplete paternal chromosome elimination resulting in aneuploidy.

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Kussell, Edo, Roy Kishony, Nathalie Q. Balaban et Stanislas Leibler. « Bacterial Persistence ». Genetics 169, n^o 4 (31 janvier 2005) : 1807–14. http://dx.doi.org/10.1534/genetics.104.035352.

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Macario, Alberto J. L., et Everly Conway de Macario. « The Archaeal Molecular Chaperone Machine : Peculiarities and Paradoxes ». Genetics 152, n^o 4 (1 août 1999) : 1277–83. http://dx.doi.org/10.1093/genetics/152.4.1277.

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Abstract A major finding within the field of archaea and molecular chaperones has been the demonstration that, while some species have the stress (heat-shock) gene hsp70(dnaK), others do not. This gene encodes Hsp70(DnaK), an essential molecular chaperone in bacteria and eukaryotes. Due to the physiological importance and the high degree of conservation of this protein, its absence in archaeal organisms has raised intriguing questions pertaining to the evolution of the chaperone machine as a whole and that of its components in particular, namely, Hsp70(DnaK), Hsp40(DnaJ), and GrpE. Another archaeal paradox is that the proteins coded by these genes are very similar to bacterial homologs, as if the genes had been received via lateral transfer from bacteria, whereas the upstream flanking regions have no bacterial markers, but instead have typical archaeal promoters, which are like those of eukaryotes. Furthermore, the chaperonin system in all archaea studied to the present, including those that possess a bacterial-like chaperone machine, is similar to that of the eukaryotic-cell cytosol. Thus, two chaperoning systems that are designed to interact with a compatible partner, e.g., the bacterial chaperone machine physiologically interacts with the bacterial but not with the eucaryal chaperonins, coexist in archaeal cells in spite of their apparent functional incompatibility. It is difficult to understand how these hybrid characteristics of the archaeal chaperoning system became established and work, if one bears in mind the classical ideas learned from studying bacteria and eukaryotes. No doubt, archaea are intriguing organisms that offer an opportunity to find novel molecules and mechanisms that will, most likely, enhance our understanding of the stress response and the protein folding and refolding processes in the three phylogenetic domains.

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Bergstrom, Carl T., Marc Lipsitch et Bruce R. Levin. « Natural Selection, Infectious Transfer and the Existence Conditions for Bacterial Plasmids ». Genetics 155, n^o 4 (1 août 2000) : 1505–19. http://dx.doi.org/10.1093/genetics/155.4.1505.

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Abstract Despite the near-ubiquity of plasmids in bacterial populations and the profound contribution of infectious gene transfer to the adaptation and evolution of bacteria, the mechanisms responsible for the maintenance of plasmids in bacterial populations are poorly understood. In this article, we address the question of how plasmids manage to persist over evolutionary time. Empirical studies suggest that plasmids are not infectiously transmitted at a rate high enough to be maintained as genetic parasites. In part i, we present a general mathematical proof that if this is the case, then plasmids will not be able to persist indefinitely solely by carrying genes that are beneficial or sometimes beneficial to their host bacteria. Instead, such genes should, in the long run, be incorporated into the bacterial chromosome. If the mobility of host-adaptive genes imposes a cost, that mobility will eventually be lost. In part ii, we illustrate a pair of mechanisms by which plasmids can be maintained indefinitely even when their rates of transmission are too low for them to be genetic parasites. First, plasmids may persist because they can transfer locally adapted genes to newly arriving strains bearing evolutionary innovations, and thereby preserve the local adaptations in the face of background selective sweeps. Second, plasmids may persist because of their ability to shuttle intermittently favored genes back and forth between various (noncompeting) bacterial strains, ecotypes, or even species.

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Lawrence, J. G., H. Ochman et D. L. Hartl. « The evolution of insertion sequences within enteric bacteria. » Genetics 131, n^o 1 (1 mai 1992) : 9–20. http://dx.doi.org/10.1093/genetics/131.1.9.

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Abstract To identify mechanisms that influence the evolution of bacterial transposons, DNA sequence variation was evaluated among homologs of insertion sequences IS1, IS3 and IS30 from natural strains of Escherichia coli and related enteric bacteria. The nucleotide sequences within each class of IS were highly conserved among E. coli strains, over 99.7% similar to a consensus sequence. When compared to the range of nucleotide divergence among chromosomal genes, these data indicate high turnover and rapid movement of the transposons among clonal lineages of E. coli. In addition, length polymorphism among IS appears to be far less frequent than in eukaryotic transposons, indicating that nonfunctional elements comprise a smaller fraction of bacterial transposon populations than found in eukaryotes. IS present in other species of enteric bacteria are substantially divergent from E. coli elements, indicating that IS are mobilized among bacterial species at a reduced rate. However, homologs of IS1 and IS3 from diverse species provide evidence that recombination events and horizontal transfer of IS among species have both played major roles in the evolution of these elements. IS3 elements from E. coli and Shigella show multiple, nested, intragenic recombinations with a distantly related transposon, and IS1 homologs from diverse taxa reveal a mosaic structure indicative of multiple recombination and horizontal transfer events.

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Townsend, Jeffrey P., Kaare M. Nielsen, Daniel S. Fisher et Daniel L. Hartl. « Horizontal Acquisition of Divergent Chromosomal DNA in Bacteria : Effects of Mutator Phenotypes ». Genetics 164, n^o 1 (1 mai 2003) : 13–21. http://dx.doi.org/10.1093/genetics/164.1.13.

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Abstract We examine the potential beneficial effects of the expanded access to environmental DNA offered by mutators on the adaptive potential of bacterial populations. Using parameters from published studies of recombination in E. coli, we find that the presence of mutators has the potential to greatly enhance bacterial population adaptation when compared to populations without mutators. In one specific example, for which three specific amino acid substitutions are required for adaptation to occur in a 300-amino-acid protein, we found a 3500-fold increase in the rate of adaptation. The probability of a beneficial acquisition decreased if more amino acid changes, or integration of longer DNA fragments, were required for adaptation. The model also predicts that mutators are more likely than nonmutator phenotypes to acquire genetic variability from a more diverged set of donor bacteria. Bacterial populations harboring mutators in a sequence heterogeneous environment are predicted to acquire most of their DNA conferring adaptation in the range of 13–30% divergence, whereas nonmutator phenotypes become adapted after recombining with more homogeneous sequences of 7–21% divergence. We conclude that mutators can accelerate bacterial adaptation when desired genetic variability is present within DNA fragments of up to ∼30% divergence.

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Dahlberg, Cecilia, et Lin Chao. « Amelioration of the Cost of Conjugative Plasmid Carriage in Eschericha coli K12 ». Genetics 165, n^o 4 (1 décembre 2003) : 1641–49. http://dx.doi.org/10.1093/genetics/165.4.1641.

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Abstract Although plasmids can provide beneficial functions to their host bacteria, they might confer a physiological or energetic cost. This study examines how natural selection may reduce the cost of carrying conjugative plasmids with drug-resistance markers in the absence of antibiotic selection. We studied two plasmids, R1 and RP4, both of which carry multiple drug resistance genes and were shown to impose an initial fitness cost on Escherichia coli. To determine if and how the cost could be reduced, we subjected plasmid-containing bacteria to 1100 generations of evolution in batch cultures. Analysis of the evolved populations revealed that plasmid loss never occurred, but that the cost was reduced through genetic changes in both the plasmids and the bacteria. Changes in the plasmids were inferred by the demonstration that evolved plasmids no longer imposed a cost on their hosts when transferred to a plasmid-free clone of the ancestral E. coli. Changes in the bacteria were shown by the lowered cost when the ancestral plasmids were introduced into evolved bacteria that had been cured of their (evolved) plasmids. Additionally, changes in the bacteria were inferred because conjugative transfer rates of evolved R1 plasmids were lower in the evolved host than in the ancestral host. Our results suggest that once a conjugative bacterial plasmid has invaded a bacterial population it will remain even if the original selection is discontinued.

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Mahan, M. J., et J. R. Roth. « Reciprocality of recombination events that rearrange the chromosome. » Genetics 120, n^o 1 (1 septembre 1988) : 23–35. http://dx.doi.org/10.1093/genetics/120.1.23.

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Abstract We describe a genetic system for studying the reciprocality of chromosomal recombination; all substrates and recombination functions involved are provided exclusively by the bacterial chromosome. The genetic system allows the recovery of both recombinant products from a single recombination event. The system was used to demonstrate the full reciprocality of three different types of recombination events: (1) intrachromosomal recombination between direct repeats, causing deletions; (2) intrachromosomal recombination between inverse homologies, causing inversion of a segment of the bacterial chromosome; and (3) circle to circle recombination (in the absence of any plasmid or phage functions). Results suggest that intrachromosomal recombination in bacteria is frequently fully reciprocal.

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Thèses sur le sujet "Bacterial genetics"

Martins, Thaísa Zanetoni. « Mutagênese sítio-dirigida da ORF XAC0024 de Xanthomonas citri subsp. citri e suas implicações no desenvolvimento do cancro cítrico / ». Jaboticabal, 2016. http://hdl.handle.net/11449/138238.

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Orientador: Jesus Aparecido Ferro
Coorientador: Helen Alves Penha
Banca: Fabrício José Jaciani
Banca: Flávia Maria de Souza Carvalho
Resumo: O cancro cítrico tem como agente causal a bactéria Xanthomonas citri subsp. citri (Xac), que afeta diferentes espécies de citros economicamente importantes. É uma doença ainda sem método curativo, e pela sua relevância e dano econômico, faz-se necessário o entendimento em termos moleculares da interação Xac-citros para o desenvolvimento de estratégias que controlem a doença. O objetivo do presente trabalho foi investigar os efeitos da deleção da ORF XAC0024 presente no genoma da Xac isolado 306, que codifica uma proteína hipotética conservada e que apresenta vários domínios putativos, entre eles o domínio peptidase M23. A hipótese é que esta proteína pode estar envolvida com a patogenicidade e/ou virulência da bactéria. Para obter o mutante ΔXAC0024 foi utilizada a técnica de mutagênese sítio-dirigida, seguida de recombinação homóloga com o vetor suicida pOK1. O mutante ΔXAC0024 foi analisado em relação às características de patogenicidade, crescimento in vivo e in vitro, capacidade de autoagregação, produção de biofilme e produção de goma xantana. O teste de patogenicidade e a curva de crescimento in vivo foram realizados em limão cravo utilizando o método de infiltração por seringa para a inoculação da bactéria. Os sintomas do desenvolvimento da doença foram registrados por fotografia digital até o 25º dia após a inoculação (dai) e a curva de crescimento in vivo também foi determinada até o 25º dai. A curva de crescimento in vitro e a agregação célula-a-célula foram analisa... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The bacteria Xanthomonas citri subsp. citri (Xac) is the causal agent of citrus canker, a disease that affects different species of economically important citrus. There is no a curative method for this disease, and do to its relevance and economic damage, it is necessary to understand at molecular level the Xac-citrus interaction in order to develop strategies to control the disease. The objective of this study was to investigate the effects of the deletion of the ORF XAC0024 present in the genome of Xac strain 306, which encodes a conserved hypothetical protein and has several putative domains, including peptidase M23 domain. It is hypothesized that this protein may be involved in the pathogenicity and / or virulence of the bacterium. For the ΔXAC0024 mutant was used for site-directed mutagenesis technique, followed by homologous recombination with the suicide vector pOK1. The ΔXAC0024 mutant was analyzed in relation to pathogenicity characteristics, growth in vivo and in vitro, self-aggregation capacity, biofilm production and production of xanthan gum. The pathogenicity test and in vivo growth curves were performed on Rangpur lime using syringe-infiltration method for the inoculation of bacteria. Symptoms of the disease development were recorded by digital photography to the 25° day after inoculation (dai) and in vivo growth curve was also determined to give the 25°. The growth curve in vitro and cell-to-cell aggregation were analyzed in liquid culture medium NB. Biofilm p... (Complete abstract click electronic access below)
Mestre

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Cock, J. M. « Bacterial nitrate reductase genes ». Thesis, University of Leeds, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.355501.

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Ennis, Don Gregory. « Genetics of SOS mutagenesis ». Diss., The University of Arizona, 1988. http://hdl.handle.net/10150/184602.

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Previous genetic evidence suggested that RecA was required in SOS mutagenesis for its regulatory role and perhaps some other nonregulatory role (Mount, 1977; Blanco et al., 1982). I undertook a genetic study which confirmed the above studies and provided further evidence that RecA protein appeared to have a dual "role in mutagenesis; first, the cleavage of LexA repressor for the derepression of specific SOS genes and second, one or more additional role(s). For these studies a new phage mutagenesis assay was developed which allows rapid scoring of SOS mutagenesis in a large number of host mutants. I next conducted a genetic analysis to determine if the newly defined RecA mutagenesis function was separable by mutation from the numerous other phenotypes which are known to be influenced by RecA protein. From the study of recA mutants it appears that the RecA mutagenesis function(s) is genetically separable from the following RecA phenotypes: LexA cleavage, lambda cI repressor cleavage, UV resistance and homologous recombination. In addition, I discovered that the LexA cleavage function and lambda cI cleavage function is also separable. I also studied in some detail the novel genetic properties that I uncovered for recA432 mutant strains. recA432 was defined as a mutagenesis defective allele (Kato and Shinoura, 1977). LexA cleavage in recA432 cells was more easily induced that in recA⁺ cells, causing lethal filamentation of these mutant cells even at very low UV doses. I concluded that the basis for the Mut⁻ phenotype was this strain's propensity to lethally filament, which complicated the detection of mutant cells. In another set of experiments, I examined the regulatory requirements for SOS mutagenesis and Weigle phage-reactivation; I wanted to determine which SOS operons must be derepressed for this process. lexA(Ind⁻) mutant cells are defective in mutagenesis because they cannot derepress specific SOS genes required in this process. I found that the selective derepression of umuDC was sufficient to restore mutagenesis to these lexA(Ind⁻) mutants; however, derepression of umuDC and recA was required for phage reactivation.

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Leiman, Sara. « Genetics and Regulation of Bacterial Biofilms ». Thesis, Harvard University, 2015. http://nrs.harvard.edu/urn-3:HUL.InstRepos:17463954.

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Bacterial biofilm formation, the construction of dense, protective, multicellular communities, is a widely conserved behavior. In some bacteria, such as the Gram-positive model organism Bacillus subtilis, the genetics controlling biofilm formation are well understood. In other bacteria, however, including the Gram-negative opportunistic pathogen Pseudomonas aeruginosa, the identities or roles of many biofilm genes remain unknown. Importantly, many proposed applications of biofilm research, particularly in the medical field, require knowledge not only of biofilm assembly but also of biofilm disassembly, the latter being a recent and underdeveloped area of study. It was previously reported that B. subtilis biofilms disassemble late in their life cycle due to the incorporation of four D-amino acids (D-leucine, D-methionine, D-tryptophan, and D-tyrosine, or D-LMWY) into peptidoglycan. It was further argued that D-LMWY specifically inhibits and disassembles the biofilms of diverse bacterial species, including B. subtilis and P. aeruginosa. Here I present a contrasting report. I describe how what had been perceived as D-LMWY-mediated biofilm inhibition is actually D-tyrosine-mediated toxicity. B. subtilis is sensitive to growth inhibition by D-tyrosine due to the absence of D-tyrosyl tRNATyr deacylase (Dtd), an enzyme that prevents the misincorporation of D-tyrosine and other D-amino acids into nascent proteins. By repairing the gene for Dtd, I was able to render B. subtilis resistant to both growth inhibition and biofilm inhibition by D-tyrosine and D-LMWY. In parallel, I recovered spontaneous mutants of B. subtilis that survive in the presence of D-LMWY. These isolates harbored mutations in pathways that regulate tRNATyr charging. Three of these mutations enhanced the expression of the gene (tyrS) for tyrosyl-tRNATyr synthetase (TyrRS), while a separate mutation improved the stereoselectivity of TyrRS. I concluded that these spontaneous D-LMWY resistance mutations were compensating for the absence of Dtd. In addition to my research on B. subtilis biofilm regulation, I demonstrated a new, non-destructive screening approach for identifying P. aeruginosa biofilm genes. Using this screen, I was able to recover a wide range of known biofilm genes as well as the new biofilm gene candidates ptsP, PA14_16550, and PA14_69700. These three genes are the focus of an ongoing study dedicated to characterizing P. aeruginosa biofilm formation, particularly as it relates to the secondary messenger cyclic di-GMP. In summary, this dissertation covers aspects of biofilm formation and dispersal in two bacterial species. My work offers mechanistic insight into D-amino acid resistance, resolves the relationship between D-amino acids and biofilms, and establishes a new tool for understanding the complexities of biofilm genetics and regulation.
Biology, Molecular and Cellular

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Parahitiyawa, Nipuna Bandara. « Phylogenetic aspects of oral bacterial microbiome ». Thesis, Click to view the E-thesis via HKUTO, 2009. http://sunzi.lib.hku.hk/hkuto/record/B43278486.

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Rollie, Clare. « Memories are made of this : investigating the CRISPR-Cas adaption mechanism ». Thesis, University of St Andrews, 2017. http://hdl.handle.net/10023/10814.

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CRISPR-Cas is an adaptive immune system unique to prokaryotes, which prevents infection by foreign genetic elements. Key to the function of CRISPR-Cas immunity is the ability to adapt to new threats in incorporating short segments, termed spacers, of invading DNA into the clustered regularly interspaced short palindromic repeat (CRISPR) array of the host. Spacers constitute immunological memories, used by CRISPR-associated (Cas) proteins to mount a sequence-specific attack on subsequent infections. The immunisation of the host is called CRISPR adaption. Adaption requires the integration of new spacers at a precise site in the CRISPR array. Two proteins, Cas1 and Cas2, are essential for adaptation; however, the mechanisms of spacer integration remain poorly understood. The work described here focused on understanding adaptation in Sulfolobus solfataricus. Using biochemical assays, I aimed to characterise the activity of the Cas1 and Cas2 proteins in this organism in order to understand their role in the insertion of new spacers. Additionally, I aimed to investigate how the expression of CRISPR-Cas components is regulated in this organism in response to viral infection. The results presented here show that expression of Cas1 was strongly upregulated in response to infection. A Csa3 protein from S. solfataricus was found to bind to the promoter for transcription of cas1, implying a role in the regulation observed. I reconstituted in vitro both the integration reaction performed by Cas1 and Cas2 proteins of S. solfataricus and the reverse of this reaction, disintegration. Cas1 was shown to impose sequence specificity on these reactions, selecting sites similar to the leader-repeat junction of the CRISPR locus. Finally, I demonstrated that, in addition to the intrinsic specificity of Cas1, there was a requirement for an additional host factor for site-specific integration in S. solfataricus.

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Tsang, J. S. H. « The physiology and genetics of bacterial dehalogenases ». Thesis, University of Kent, 1987. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.380588.

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Koh, Cheng Gee. « New approaches for mapping bacterial genomes ». Thesis, University of Cambridge, 1992. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.240188.

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Cook, Marisa Anne. « Replicons derived from endogenously isolated plasmids used to classify plasmids occurring in marine sediment bacteria ». Thesis, Georgia Institute of Technology, 2001. http://hdl.handle.net/1853/25736.

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Okuklu, Burcu Güneş Hatice. « Investigation of chromosomal and plasmid dna profiles of lactococcus lactics ssp. lactis/ ». [s.l.] : [s.n.], 2005. http://library.iyte.edu.tr/tezler/master/biyoloji/T000396.pdf.

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Thesis (Master)--İzmir Institute of Technology, İzmir, 2005
Keywords: Lactococcus lactis ssp. lactis, chromosome profiling, pulsed field gel electrophoresis, plasmid profiling, plasmid stability. Includes bibliographical references (leaves 58-63)

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Livres sur le sujet "Bacterial genetics"

E, Trempy J., dir. Fundamental bacterial genetics. Malden, MA : Blackwell Science, 2004.

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Trempy, Janine. Fundamental bacterial genetics. Oxford : Blackwell, 2004.

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Birge, Edward A. Bacterial and Bacteriophage Genetics. New York, NY : Springer New York, 2000. http://dx.doi.org/10.1007/978-1-4757-3258-0.

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Birge, Edward A. Bacterial and Bacteriophage Genetics. New York, NY : Springer New York, 1988. http://dx.doi.org/10.1007/978-1-4757-1995-6.

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Birge, Edward A. Bacterial and Bacteriophage Genetics. New York, NY : Springer New York, 1994. http://dx.doi.org/10.1007/978-1-4757-2328-1.

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A, Hopwood D., et Chater K. F, dir. Genetics of bacterial diversity. London : Academic Press, 1989.

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B, Goldberg Joanna, dir. Genetics of bacterial polysaccharides. Boca Raton, Fl : CRC Press, 1999.

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Marshall, William. Of microbes and men : The emotions, drama, and mystery of a struggle to correct a 125-year-old mistake and improve our defenses against epidemics and bioterrorism : a public affairs book. Bloomington, IN : AuthorHouse, 2008.

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Chapitres de livres sur le sujet "Bacterial genetics"

Konwar, Bolin Kumar. « Biosurfactant Genetics ». Dans Bacterial Biosurfactants, 49–70. Boca Raton : Apple Academic Press, 2022. http://dx.doi.org/10.1201/9781003188131-5.

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Snyder, Lori A. S. « Genetics ». Dans Bacterial Genetics and Genomics, 173–86. 2^e éd. Boca Raton : Garland Science, 2024. http://dx.doi.org/10.1201/9781003380436-15.

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Birge, Edward A. « Applied Bacterial Genetics ». Dans Bacterial and Bacteriophage Genetics, 374–92. New York, NY : Springer New York, 1994. http://dx.doi.org/10.1007/978-1-4757-2328-1_16.

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Birge, Edward A. « Applied Bacterial Genetics ». Dans Bacterial and Bacteriophage Genetics, 463–86. New York, NY : Springer New York, 2000. http://dx.doi.org/10.1007/978-1-4757-3258-0_16.

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Birge, Edward A. « Bacterial Evolution ». Dans Bacterial and Bacteriophage Genetics, 393–409. New York, NY : Springer New York, 1994. http://dx.doi.org/10.1007/978-1-4757-2328-1_17.

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Birge, Edward A. « Bacterial Evolution ». Dans Bacterial and Bacteriophage Genetics, 487–510. New York, NY : Springer New York, 2000. http://dx.doi.org/10.1007/978-1-4757-3258-0_17.

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Snyder, Lori A. S. « Bacterial Response ». Dans Bacterial Genetics and Genomics, 225–39. 2^e éd. Boca Raton : Garland Science, 2024. http://dx.doi.org/10.1201/9781003380436-19.

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Snyder, Lori A. S. « Bacterial Evolution ». Dans Bacterial Genetics and Genomics, 257–68. 2^e éd. Boca Raton : Garland Science, 2024. http://dx.doi.org/10.1201/9781003380436-21.

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Snyder, Lori A. S. « Bacterial Adaptation ». Dans Bacterial Genetics and Genomics, 241–55. 2^e éd. Boca Raton : Garland Science, 2024. http://dx.doi.org/10.1201/9781003380436-20.

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Stead, Christopher M., Aaron C. Pride et M. Stephen Trent. « Genetics and Biosynthesis of Lipid A ». Dans Bacterial Lipopolysaccharides, 163–93. Vienna : Springer Vienna, 2011. http://dx.doi.org/10.1007/978-3-7091-0733-1_6.

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Actes de conférences sur le sujet "Bacterial genetics"

Самойлова, Анна. « Бактериофаги Pseudomonas syringae pv. syringae перспективные в подавлении развития бактериального рака плодовых ». Dans VIIth International Scientific Conference “Genetics, Physiology and Plant Breeding”. Institute of Genetics, Physiology and Plant Protection, Republic of Moldova, 2021. http://dx.doi.org/10.53040/gppb7.2021.88.

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Five Pseudomonas syringae pv. syringae bacteriophages were isolated from the quince, apple and pear. After a detailed study, the isolated bacteriophages could be used for biocontrol of the bacterial canker patho-gen. One of the isolated phages was active against the causative agents of bacterial canker and fire blight.

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« The bacterial impact on the transcriptional activity of DCL2 and DCL4 genes in wheat plants infected with Stagonospora nodorum ». Dans Plant Genetics, Genomics, Bioinformatics, and Biotechnology. Novosibirsk ICG SB RAS 2021, 2021. http://dx.doi.org/10.18699/plantgen2021-185.

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« Fine mapping of rice bacterial leaf blight resistance loci to major Korean races of Xoo (Xanthomonas oryzae) and development markers ». Dans Plant Genetics, Genomics, Bioinformatics, and Biotechnology. Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences, 2019. http://dx.doi.org/10.18699/plantgen2019-100.

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Musleh, Mohammed, et Valentina Diaconu. « Aplicarea pesticidelor bioraționale la plantațiile de piersici în zona centrală a Republicii Moldova ». Dans VIIth International Scientific Conference “Genetics, Physiology and Plant Breeding”. Institute of Genetics, Physiology and Plant Protection, Republic of Moldova, 2021. http://dx.doi.org/10.53040/gppb7.2021.87.

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In this paper, the results of application of plant extracts, bioelicitors – Reglalg, algae extract – Spi-rogira sp., are shown. A mix of unsaturated fatty acids, aldehydes, ketones and other active components - 0.5 l / ha and Paurin - bacterial preparation (based on Agrobacterium tumefaciens) - 2.0 l / ha, which as growth regulators, contribute to increased peach resistance to different diseases.

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« The mechanism of the additive action of bacterial compositions Bacillus spp. in the defense response of common wheat against greenbug aphid Schizaphis graminum ». Dans Plant Genetics, Genomics, Bioinformatics, and Biotechnology. Novosibirsk ICG SB RAS 2021, 2021. http://dx.doi.org/10.18699/plantgen2021-173.

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Voloşciuc, Leonid, Boris Pînzaru, Tatiana Scerbacova, Aurelia Stingaci, Pantelimon Zavtoni, Andrei Lungu et Stefan Crucean. « Extinderea gamei de preparate biologice de protecție a plantelor pentru agricultura convențională și ecologică ». Dans VIIth International Scientific Conference “Genetics, Physiology and Plant Breeding”. Institute of Genetics, Physiology and Plant Protection, Republic of Moldova, 2021. http://dx.doi.org/10.53040/gppb7.2021.95.

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The global population is projected to increase by 30 % to 9,2 billion by 2050 and this increased population density is estimated to increase demand for food production by 70 %. One of the principal di-rections of biological plant protection is elaboration of technologies for production and application of bio-logical preparations for combat not only of the noxious insects but also of pathogen agents which cannot be efficiently combated by other means of biological control. This report presents the results of state reg-istration of 5 baculoviral, 1 bacterial and 3 fungal preparations for combating pest insects, phytopathogen agents and nematodes.

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« Studying the infection rate of seeds of various genotypes of sweet sorghum (Sorghum bicolor L.) by fungus and bacterial microflora ». Dans Current Challenges in Plant Genetics, Genomics, Bioinformatics, and Biotechnology. Institute of Cytology and Genetics, Siberian Branch of the Russian Academy of Sciences Novosibirsk State University, 2019. http://dx.doi.org/10.18699/icg-plantgen2019-25.

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Ali SAEED, Eiman. « COVID-19 : A RETROSPECTIVE MINI REVIEW ON THE PANDEMIC VIRUS, IMMUNOLOGICAL ASPECTS AND BACTERIAL CO-INFECTIONS ». Dans VI.International Scientific Congress of Pure,Applied and Technological Sciences. Rimar Academy, 2022. http://dx.doi.org/10.47832/minarcongress6-41.

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In 2019 the Corona pandemic spread in Wuhan City, Hubei, China. It is a disease officially known as "coronavirus disease 2019; COVID-19", which is the pathogen of respiratory tract infection and its genome sequence have been fully identified. The genetic sequence of COVID-19 showed a similar but distinct genome content for both SARS-CoV and MERS-CoV. Clinical evidence and genetics point to the course of this pandemic. Open access data and genomic sequencing combined with the development of a specialized vaccine against infection with this virus, it will give us additional information about what this virus is, the nature of the immune response generated against it and plan for the herd immunity by vaccination. In current study, we review the role of innate and acquired immunity against COVID-19 and how it works in the host's body. Then, talk about herd immunity and how can reach it to protect the population from this virus. Also, focused in this review on associated bacterial infections with viral respiratory infections.

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Dantes, Raymund B., John Metcalfe, Adithya Cattamanchi, Elizabeth Kim, Midori Kato-Maeda, Philip C. Hopewell et Payam Nahid. « Impact Of Bacterial Genetics On The Clinical Characteristics And Outcomes Of Isoniazid Mono-resistant Mycobacterium Tuberculosis ». Dans American Thoracic Society 2010 International Conference, May 14-19, 2010 • New Orleans. American Thoracic Society, 2010. http://dx.doi.org/10.1164/ajrccm-conference.2010.181.1_meetingabstracts.a5469.

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Chen, Xiaowei, Daniel L. Worthley, Zhongming Ge, Yagnesh Tailor, Christian Kaufman, Lenzie Cheaney, Lesley Kline et al. « Abstract A100:Helicobacter hepaticuscontributes to mammary gland carcinogenesis through bacterial translocation and subsequent expansion of cancer-promoting myeloid-derived suppressor cells ». Dans Abstracts : AACR Special Conference on Advances in Breast Cancer Research : Genetics, Biology, and Clinical Applications - October 3-6, 2013 ; San Diego, CA. American Association for Cancer Research, 2013. http://dx.doi.org/10.1158/1557-3125.advbc-a100.

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Rapports d'organisations sur le sujet "Bacterial genetics"

Velsko, S. Bacterial Population Genetics in a Forensic Context. Office of Scientific and Technical Information (OSTI), novembre 2009. http://dx.doi.org/10.2172/972405.

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Gutnick, David, et David L. Coplin. Role of Exopolysaccharides in the Survival and Pathogenesis of the Fire Blight Bacterium, Erwinia amylovora. United States Department of Agriculture, septembre 1994. http://dx.doi.org/10.32747/1994.7568788.bard.

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Fireblight, a disease of apples and pears, is caused by Erwinia amylovora. Mutants of E. amylovora that do not produce the extreacellular polysaccharide (EPS), amylovoran, are avirulent. A similar EPS, stewartan, is produced by E. stewartii, which caused Stewart's wilt of corn, and which has also been implicated in the virulence of this strain. Both stewartan and amylovoran are type 1 capsular polysaccharides, typified by the colanic acid slime produced by Escherichia coli. Extracellular polysaccharide slime and capsules are important for the virulence of bacterial pathogens of plants and animals and to enhance their survival and dissemination outside of the host. The goals of this project were to examine the importance of polysaccharide structure on the pathogenicity and survival properties of three pathogenic bacteria: Erwinia amylovora, Erwinia stewartii and Escherichia coli. The project was a collaboration between the laboratories of Dr. Gutnick (PI, E. coli genetics and biochemistry), Dr. Coplin (co-PI, E. stewartii genetics) and Dr. Geider (unfunded collaborator, E. amylovora genetics and EPS analysis). Structural analysis of the EPSs, sequence analysis of the biosynthetic gene clusters and site-directed mutagenesis of individual cps and ams genes revealed that the three gene clusters shared common features for polysaccharide polymerization, translocation, and precursor synthesis as well as in the modes of transcriptional regulation. Early EPS production resulted in decreased virulence, indicating that EPS, although required for pathogenicity, is anot always advantageous and pathogens must regulate its production carefully.

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Elbaum, Michael, et Peter J. Christie. Type IV Secretion System of Agrobacterium tumefaciens : Components and Structures. United States Department of Agriculture, mars 2013. http://dx.doi.org/10.32747/2013.7699848.bard.

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Objectives: The overall goal of the project was to build an ultrastructural model of the Agrobacterium tumefaciens type IV secretion system (T4SS) based on electron microscopy, genetics, and immunolocalization of its components. There were four original aims: Aim 1: Define the contributions of contact-dependent and -independent plant signals to formation of novel morphological changes at the A. tumefaciens polar membrane. Aim 2: Genetic basis for morphological changes at the A. tumefaciens polar membrane. Aim 3: Immuno-localization of VirB proteins Aim 4: Structural definition of the substrate translocation route. There were no major revisions to the aims, and the work focused on the above questions. Background: Agrobacterium presents a unique example of inter-kingdom gene transfer. The process involves cell to cell transfer of both protein and DNA substrates via a contact-dependent mechanism akin to bacterial conjugation. Transfer is mediated by a T4SS. Intensive study of the Agrobacterium T4SS has made it an archetypal model for the genetics and biochemistry. The channel is assembled from eleven protein components encoded on the B operon in the virulence region of the tumor-inducing plasmid, plus an additional coupling protein, VirD4. During the course of our project two structural studies were published presenting X-ray crystallography and three-dimensional reconstruction from electron microscopy of a core complex of the channel assembled in vitro from homologous proteins of E. coli, representing VirB7, VirB9, and VirB10. Another study was published claiming that the secretion channels in Agrobacterium appear on helical arrays around the membrane perimeter and along the entire length of the bacterium. Helical arrangements in bacterial membranes have since fallen from favor however, and that finding was partially retracted in a second publication. Overall, the localization of the T4SS within the bacterial membranes remains enigmatic in the literature, and we believe that our results from this project make a significant advance. Summary of achievements : We found that polar inflations and other membrane disturbances relate to the activation conditions rather than to virulence protein expression. Activation requires low pH and nutrient-poor medium. These stress conditions are also reflected in DNA condensation to varying degrees. Nonetheless, they must be considered in modeling the T4SS as they represent the relevant conditions for its expression and activity. We identified the T4SS core component VirB7 at native expression levels using state of the art super-resolution light microscopy. This marker of the secretion system was found almost exclusively at the cell poles, and typically one pole. Immuno-electron microscopy identified the protein at the inner membrane, rather than at bridges across the inner and outer membranes. This suggests a rare or transient assembly of the secretion-competent channel, or alternatively a two-step secretion involving an intermediate step in the periplasmic space. We followed the expression of the major secreted effector, VirE2. This is a single-stranded DNA binding protein that forms a capsid around the transferred oligonucleotide, adapting the bacterial conjugation to the eukaryotic host. We found that over-expressed VirE2 forms filamentous complexes in the bacterial cytoplasm that could be observed both by conventional fluorescence microscopy and by correlative electron cryo-tomography. Using a non-retentive mutant we observed secretion of VirE2 from bacterial poles. We labeled the secreted substrates in vivo in order detect their secretion and appearance in the plant cells. However the low transfer efficiency and significant background signal have so far hampered this approach.

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Cahaner, Avigdor, Susan J. Lamont, E. Dan Heller et Jossi Hillel. Molecular Genetic Dissection of Complex Immunocompetence Traits in Broilers. United States Department of Agriculture, août 2003. http://dx.doi.org/10.32747/2003.7586461.bard.

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Objectives: (1) Evaluate Immunocompetence-OTL-containing Chromosomal Regions (ICRs), marked by microsatellites or candidate genes, for magnitude of direct effect and for contribution to relationships among multiple immunocompetence, disease-resistance, and growth traits, in order to estimate epistatic and pleiotropic effects and to predict the potential breeding applications of such markers. (2) Evaluate the interaction of the ICRs with genetic backgrounds from multiple sources and of multiple levels of genetic variation, in order to predict the general applicability of molecular genetic markers across widely varied populations. Background: Diseases cause substantial economic losses to animal producers. Emerging pathogens, vaccine failures and intense management systems increase the impact of diseases on animal production. Moreover, zoonotic pathogens are a threat to human food safety when microbiological contamination of animal products occurs. Consumers are increasingly concerned about drug residues and antibiotic- resistant pathogens derived from animal products. The project used contemporary scientific technologies to investigate the genetics of chicken resistance to infectious disease. Genetic enhancement of the innate resistance of chicken populations provides a sustainable and ecologically sound approach to reduce microbial loads in agricultural populations. In turn, animals will be produced more efficiently with less need for drug treatment and will pose less of a potential food-safety hazard. Major achievements, conclusions and implications:. The PI and co-PIs had developed a refined research plan, aiming at the original but more focused objectives, that could be well-accomplished with the reduced awarded support. The successful conduct of that research over the past four years has yielded substantial new information about the genes and genetic markers that are associated with response to two important poultry pathogens, Salmonella enteritidis (SE) and Escherichia coli (EC), about variation of immunocompetence genes in poultry, about relationships of traits of immune response and production, and about interaction of genes with environment and with other genes and genetic background. The current BARD work has generated a base of knowledge and expertise regarding the genetic variation underlying the traits of immunocompetence and disease resistance. In addition, unique genetic resource populations of chickens have been established in the course of the current project, and they are essential for continued projects. The US laboratory has made considerable progress in studies of the genetics of resistance to SE. Microsatellite-marked chromosomal regions and several specific genes were linked to SE vaccine response or bacterial burden and the important phenomenon of gene interaction was identified in this system. In total, these studies demonstrate the role of genetics in SE response, the utility of the existing resource population, and the expertise of the research group in conducting such experiments. The Israeli laboratories had showed that the lines developed by selection for high or low level of antibody (Ab) response to EC differ similarly in Ab response to several other viral and bacterial pathogens, indicating the existence of a genetic control of general capacity of Ab response in young broilers. It was also found that the 10w-Ab line has developed, possibly via compensatory "natural" selection, higher cellular immune response. At the DNA levels, markers supposedly linked to immune response were identified, as well as SNP in the MHC, a candidate gene responsible for genetic differences in immunocompetence of chickens.

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Zhao, Bingyu, Saul Burdman, Ronald Walcott, Tal Pupko et Gregory Welbaum. Identifying pathogenic determinants of Acidovorax citrulli toward the control of bacterial fruit blotch of cucurbits. United States Department of Agriculture, janvier 2014. http://dx.doi.org/10.32747/2014.7598168.bard.

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The specific objectives of this BARD proposal were: Use a comparative genomics approach to identify T3Es in group I, II and III strains of A. citrulli. Determine the bacterial genes contributing to host preference. Develop mutant strains that can be used for biological control of BFB. Background to the topic: Bacterial fruit blotch (BFB) of cucurbits, caused by Acidovoraxcitrulli, is a devastating disease that affects watermelon (Citrulluslanatus) and melon (Cucumismelo) production worldwide, including both Israel and USA. Three major groups of A. citrullistrains have been classified based on their virulence on host plants, genetics and biochemical properties. The host selection could be one of the major factors that shape A. citrullivirulence. The differences in the repertoire of type III‐ secreted effectors (T3Es) among the three A. citrulligroups could play a major role in determining host preferential association. Currently, there are only 11 A. citrulliT3Es predicted by the annotation of the genome of the group II strain, AAC00‐1. We expect that new A. citrulliT3Es can be identified by a combination of bioinformatics and experimental approaches, which may help us to further define the relationship of T3Es and host preference of A. citrulli. Implications, both scientific and agricultural: Enriching the information on virulence and avirulence functions of T3Es will contribute to the understanding of basic aspects of A. citrulli‐cucurbit interactions. In the long term, it will contribute to the development of durable BFB resistance in commercial varieties. In the short term, identifying bacterial genes that contribute to virulence and host preference will allow the engineering of A. citrullimutants that can trigger SAR in a given host. If applied as seed treatments, these should significantly improve the effectiveness and efficacy of BFB management in melon and atermelon production.

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Zhao, Bingyu, Saul Burdman, Ronald Walcott et Gregory E. Welbaum. Control of Bacterial Fruit Blotch of Cucurbits Using the Maize Non-Host Disease Resistance Gene Rxo1. United States Department of Agriculture, septembre 2013. http://dx.doi.org/10.32747/2013.7699843.bard.

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The specific objectives of this BARD proposal were: (1) To determine whether Rxol can recognize AacavrRxo1 to trigger BFB disease resistance in stable transgenic watermelon plants. (2) To determine the distribution of Aac-avrRxo1 in a global population of Aae and to characterize the biological function of Aac-avrRxo1. (3) To characterize other TIS effectors of Aae and to identify plant R gene(s) that can recognize conserved TIS effectors of this pathogen. Background to the topic: Bacterial fruit blotch (BFB) of cucurbits, caused by Acidovorax avenae subsp. citrulli (Aae), is a devastating disease that affects watermelon (Citrullus lanatus) and melon (Cucumis melo) production worldwide, including both Israel and USA. Two major groups of Aae strains have been classified based on their virulence on host plants, genetics and biochemical properties. Thus far, no effective resistance genes have been identified from cucurbit germplasm. In this project, we assessed the applicability of a non-host disease resistance gene, Rxol, to control BFB in watermelon. We also tried to identify Aae type III secreted (TIS) effectors that can be used as molecular probes to identify novel disease resistance genes in both cucurbits and Nieotianatabaeum. Major conclusions, solutions, achievements: We generated five independent transgenic watermelon (cv. Sugar Babay) plants expressing the Rxol gene. The transgenic plants were evaluated with Aae strains AAC001 and M6 under growth chamber conditions. All transgenic plants were found to be susceptible to both Aae strains. It is possible that watermelon is missing other signaling components that are required for Rxol-mediated disease resistance. In order to screen for novel BFB resistance genes, we inoculated two Aae strains on 60 Nieotiana species. Our disease assay revealed Nicotiana tabaeum is completely resistant to Aae, while its wild relative N. benthamiana is susceptible to Aae. We further demonstrated that Nieotiana benthamiana can be used as a surrogate host for studying the mechanisms of pathogenesis of Aae. We cloned 11 TIS effector genes including the avrRxolhomologues from the genomes of 22 Aae strains collected worldwide. Sequencing analysis revealed that functional avrRxol is conserved in group" but not group I Aae strains. Three effector genes- Aave_1548, Aave_2166 and Aave_2708- possessed the ability to trigger an HR response in N. tabacum when they were transiently expressed by Agrobaeterium. We conclude that N. tabacum carries at least three different non-host resistance genes that can specifically recognize AaeTIS effectors to trigger non-host resistance. Screening 522 cucurbits genotypes with two Aae strains led us to identify two germplasm (P1536473 and P1273650) that are partially resistant to Aae. Interestingly, transient expression of the TIS effector, Aave_1548, in the two germplasms also triggered HR-Iike cell death, which suggests the two lines may carry disease resistance genes that can recognize Aave_1548. Importantly, we also demonstrated that this effector contributes to the virulence of the bacterium in susceptible plants. Therefore, R genes that recognize effector Aave1548 have great potential for breeding for BFB resistance. To better understand the genome diversity of Aae strains, we generated a draft genome sequence of the Israeli Aae strain, M6 (Group I) using Iliumina technology. Comparative analysis of whole genomes of AAC001, and M6 allowed us to identify several effectors genes that differentiate groups I and II. Implications, both scientific and agricultural: The diversity of TIS effectors in group I and II strains of Aae suggests that a subset of effectors could contribute to the host range of group I and II Aae strains. Analysis of these key effectors in a larger Aae population may allow us to predict which cucurbit hosts may be at risk to BFB. Additionally, isolation of tobacco and cucurbit Rgenes that can recognize Aae type III effectors may offer new genetic resources for controlling BFB.

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Lidstrom, Mary E. Genetics in Marine Methane-Oxidizing Bacteria. Fort Belvoir, VA : Defense Technical Information Center, février 1989. http://dx.doi.org/10.21236/ada203790.

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Welker, N. E. Genetics of thermophilic bacteria. [Bacillus stearothermophilus:a2]. Office of Scientific and Technical Information (OSTI), janvier 1991. http://dx.doi.org/10.2172/6057022.

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CALIFORNIA UNIV BERKELEY. Genetics in Marine Methane-Oxidizing Bacteria. Fort Belvoir, VA : Defense Technical Information Center, février 1990. http://dx.doi.org/10.21236/ada218398.

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Morrison, Mark, Joshuah Miron, Edward A. Bayer et Raphael Lamed. Molecular Analysis of Cellulosome Organization in Ruminococcus Albus and Fibrobacter Intestinalis for Optimization of Fiber Digestibility in Ruminants. United States Department of Agriculture, mars 2004. http://dx.doi.org/10.32747/2004.7586475.bard.

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Improving plant cell wall (fiber) degradation remains one of the highest priority research goals for all ruminant enterprises dependent on forages, hay, silage, or other fibrous byproducts as energy sources, because it governs the provision of energy-yielding nutrients to the host animal. Although the predominant species of microbes responsible for ruminal fiber degradation are culturable, the enzymology and genetics underpinning the process are poorly defined. In that context, there were two broad objectives for this proposal. The first objective was to identify the key cellulosomal components in Ruminococcus albus and to characterize their structural features as well as regulation of their expression, in response to polysaccharides and (or) P AA/PPA. The second objective was to evaluate the similarities in the structure and architecture of cellulosomal components between R. albus and other ruminal and non-ruminal cellulolytic bacteria. The cooperation among the investigators resulted in the identification of two glycoside hydrolases rate-limiting to cellulose degradation by Ruminococcus albus (Cel48A and CeI9B) and our demonstration that these enzymes possess a novel modular architecture specific to this bacterium (Devillard et al. 2004). We have now shown that the novel X-domains in Cel48A and Cel9B represent a new type of carbohydrate binding module, and the enzymes are not part of a ceiluiosome-like complex (CBM37, Xu et al. 2004). Both Cel48A and Cel9B are conditionally expressed in response to P AA/PPA, explaining why cellulose degradation in this bacterium is affected by the availability of these compounds, but additional studies have shown for the first time that neither PAA nor PPA influence xylan degradation by R. albus (Reveneau et al. 2003). Additionally, the R. albus genome sequencing project, led by the PI. Morrison, has supported our identification of many dockerin containing proteins. However, the identification of gene(s) encoding a scaffoldin has been more elusive, and recombinant proteins encoding candidate cohesin modules are now being used in Israel to verify the existence of dockerin-cohesin interactions and cellulosome production by R. albus. The Israeli partners have also conducted virtually all of the studies specific to the second Objective of the proposal. Comparative blotting studies have been conducted using specific antibodies prepare against purified recombinant cohesins and X-domains, derived from cellulosomal scaffoldins of R. flavefaciens 17, a Clostridium thermocellum mutant-preabsorbed antibody preparation, or against CbpC (fimbrial protein) of R. albus 8. The data also suggest that additional cellulolytic bacteria including Fibrobacter succinogenes S85, F. intestinalis DR7 and Butyrivibrio fibrisolvens Dl may also employ cellulosomal modules similar to those of R. flavefaciens 17. Collectively, our work during the grant period has shown that R. albus and other ruminal bacteria employ several novel mechanisms for their adhesion to plant surfaces, and produce both cellulosomal and non-cellulosomal forms of glycoside hydrolases underpinning plant fiber degradation. These improvements in our mechanistic understanding of bacterial adhesion and enzyme regulation now offers the potential to: i) optimize ruminal and hindgut conditions by dietary additives to maximize fiber degradation (e.g. by the addition of select enzymes or PAA/PPA); ii) identify plant-borne influences on adhesion and fiber-degradation, which might be overcome (or improved) by conventional breeding or transgenic plant technologies and; iii) engineer or select microbes with improved adhesion capabilities, cellulosome assembly and fiber degradation. The potential benefits associated with this research proposal are likely to be realized in the medium term (5-10 years).

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