Journal articles: 'Algal-bacterial symbiosis'

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Mu, Ruimin, Qingyang Guo, Feng Qi, Yantian Jia, Qianya Meng, and Gejiang Yu. "Advances in Studies on Nitrogen and Phosphorus Removal by Microalgal-Bacterial Consortia." E3S Web of Conferences 293 (2021): 01006. http://dx.doi.org/10.1051/e3sconf/202129301006.

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With the development of life and industry, the nutrients in sewage increased gradually. The emerging symbiotic system of algal and bacteria has remarkable effect in removing nutrients such as nitrogen and phosphorus. In this paper, the influence of nitrogen and phosphorus on bacteria-algal consortia and the absorption mechanism of nitrogen and phosphorus by the interaction of bacteria-algal consortia were analyzed, and a variety of methods for studying bacteria-algal consortia were summarized, mainly using isotope tracer technology to study the research results of bacteria and algae absorbing nitrogen and phosphorus in water. This method is of great significance for analyzing the mechanism of the treatment of nitrogen and phosphorus by the bacterial-algal symbiosis system from the microscopic point of view.

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Qi, Yun, Xingyu Chen, Zhan Hu, Chunfeng Song, and Yuanlu Cui. "Bibliometric Analysis of Algal-Bacterial Symbiosis in Wastewater Treatment." International Journal of Environmental Research and Public Health 16, no. 6 (March 26, 2019): 1077. http://dx.doi.org/10.3390/ijerph16061077.

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In recent years, the algae-bacteria symbiotic system has played a significant role in the sustainable development of wastewater treatment. With the continuous expansion of research outputs, publications related to wastewater treatment via algal-bacterial consortia appear to be on the rise. Based on SCI-EXPANDED database, this study investigated the research activities and tendencies of algae-bacteria symbiotic wastewater treatment technology by bibliometric method from 1998 to 2017. The results indicated that environmental sciences and ecology was the most productive subject categories, followed by engineering. Bioresource Technology was the most prominent journal in this field with considerable academic influence. China (146), USA (139) and Spain (76) had the largest amount of publications. Among them, USA was in a leading position in international cooperation, with the highest h-index (67) in 79 countries/territories. The cooperation between China and USA was the closest. The cooperative publishing rate of the Chinese Academy of Sciences was 83.33%, but most of them were in cooperation with domestic institutions, while international cooperation was relatively limited. Methane production, biofuel production, and extracellular polymeric substance were future focal frontiers of research, and this field had gradually become a multi-perspective and inter-disciplinary approach combining biological, environmental and energy technologies.

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Seyedsayamdost, Mohammad R., Gavin Carr, Roberto Kolter, and Jon Clardy. "Roseobacticides: Small Molecule Modulators of an Algal-Bacterial Symbiosis." Journal of the American Chemical Society 133, no. 45 (November 16, 2011): 18343–49. http://dx.doi.org/10.1021/ja207172s.

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Ho, Yuh-Shan. "Comment to: Qi, Yi, et al. “Bibliometric Analysis of Algal-Bacterial Symbiosis in Wastewater Treatment”, Int. J. Environ. Res. Public Health 2019, 16, 1077." International Journal of Environmental Research and Public Health 16, no. 11 (June 7, 2019): 2034. http://dx.doi.org/10.3390/ijerph16112034.

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Vallet, Marine, Filip Kaftan, Veit Grabe, Fatemeh Ghaderiardakani, Simona Fenizia, Aleš Svatoš, Georg Pohnert, and Thomas Wichard. "A new glance at the chemosphere of macroalgal–bacterial interactions: In situ profiling of metabolites in symbiosis by mass spectrometry." Beilstein Journal of Organic Chemistry 17 (May 19, 2021): 1313–22. http://dx.doi.org/10.3762/bjoc.17.91.

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Symbiosis is a dominant form of life that has been observed numerous times in marine ecosystems. For example, macroalgae coexist with bacteria that produce factors that promote algal growth and morphogenesis. The green macroalga Ulva mutabilis (Chlorophyta) develops into a callus-like phenotype in the absence of its essential bacterial symbionts Roseovarius sp. MS2 and Maribacter sp. MS6. Spatially resolved studies are required to understand symbiont interactions at the microscale level. Therefore, we used mass spectrometry profiling and imaging techniques with high spatial resolution and sensitivity to gain a new perspective on the mutualistic interactions between bacteria and macroalgae. Using atmospheric pressure scanning microprobe matrix-assisted laser desorption/ionisation high-resolution mass spectrometry (AP-SMALDI-HRMS), low-molecular-weight polar compounds were identified by comparative metabolomics in the chemosphere of Ulva. Choline (2-hydroxy-N,N,N-trimethylethan-1-aminium) was only determined in the alga grown under axenic conditions, whereas ectoine (1,4,5,6-tetrahydro-2-methyl-4-pyrimidinecarboxylic acid) was found in bacterial presence. Ectoine was used as a metabolic marker for localisation studies of Roseovarius sp. within the tripartite community because it was produced exclusively by these bacteria. By combining confocal laser scanning microscopy (cLSM) and AP-SMALDI-HRMS, we proved that Roseovarius sp. MS2 settled mainly in the rhizoidal zone (holdfast) of U. mutabilis. Our findings provide the fundament to decipher bacterial symbioses with multicellular hosts in aquatic ecosystems in an ecologically relevant context. As a versatile tool for microbiome research, the combined AP-SMALDI and cLSM imaging analysis with a resolution to level of a single bacterial cell can be easily applied to other microbial consortia and their hosts. The novelty of this contribution is the use of an in situ setup designed to avoid all types of external contamination and interferences while resolving spatial distributions of metabolites and identifying specific symbiotic bacteria.

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Greshake Tzovaras, Bastian, Francisca H. I. D. Segers, Anne Bicker, Francesco Dal Grande, Jürgen Otte, Seyed Yahya Anvar, Thomas Hankeln, Imke Schmitt, and Ingo Ebersberger. "What Is in Umbilicaria pustulata? A Metagenomic Approach to Reconstruct the Holo-Genome of a Lichen." Genome Biology and Evolution 12, no. 4 (March 12, 2020): 309–24. http://dx.doi.org/10.1093/gbe/evaa049.

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Abstract Lichens are valuable models in symbiosis research and promising sources of biosynthetic genes for biotechnological applications. Most lichenized fungi grow slowly, resist aposymbiotic cultivation, and are poor candidates for experimentation. Obtaining contiguous, high-quality genomes for such symbiotic communities is technically challenging. Here, we present the first assembly of a lichen holo-genome from metagenomic whole-genome shotgun data comprising both PacBio long reads and Illumina short reads. The nuclear genomes of the two primary components of the lichen symbiosis—the fungus Umbilicaria pustulata (33 Mb) and the green alga Trebouxia sp. (53 Mb)—were assembled at contiguities comparable to single-species assemblies. The analysis of the read coverage pattern revealed a relative abundance of fungal to algal nuclei of ∼20:1. Gap-free, circular sequences for all organellar genomes were obtained. The bacterial community is dominated by Acidobacteriaceae and encompasses strains closely related to bacteria isolated from other lichens. Gene set analyses showed no evidence of horizontal gene transfer from algae or bacteria into the fungal genome. Our data suggest a lineage-specific loss of a putative gibberellin-20-oxidase in the fungus, a gene fusion in the fungal mitochondrion, and a relocation of an algal chloroplast gene to the algal nucleus. Major technical obstacles during reconstruction of the holo-genome were coverage differences among individual genomes surpassing three orders of magnitude. Moreover, we show that GC-rich inverted repeats paired with nonrandom sequencing error in PacBio data can result in missing gene predictions. This likely poses a general problem for genome assemblies based on long reads.

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Wilson, Maxwell Z., Rurun Wang, Zemer Gitai, and Mohammad R. Seyedsayamdost. "Mode of action and resistance studies unveil new roles for tropodithietic acid as an anticancer agent and the γ-glutamyl cycle as a proton sink." Proceedings of the National Academy of Sciences 113, no. 6 (January 22, 2016): 1630–35. http://dx.doi.org/10.1073/pnas.1518034113.

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While we have come to appreciate the architectural complexity of microbially synthesized secondary metabolites, far less attention has been paid to linking their structural features with possible modes of action. This is certainly the case with tropodithietic acid (TDA), a broad-spectrum antibiotic generated by marine bacteria that engage in dynamic symbioses with microscopic algae. TDA promotes algal health by killing unwanted marine pathogens; however, its mode of action (MoA) and significance for the survival of an algal–bacterial miniecosystem remains unknown. Using cytological profiling, we herein determine the MoA of TDA and surprisingly find that it acts by a mechanism similar to polyether antibiotics, which are structurally highly divergent. We show that like polyether drugs, TDA collapses the proton motive force by a proton antiport mechanism, in which extracellular protons are exchanged for cytoplasmic cations. The α-carboxy-tropone substructure is ideal for this purpose as the proton can be carried on the carboxyl group, whereas the basicity of the tropylium ion facilitates cation export. Based on similarities to polyether anticancer agents we have further examined TDA’s cytotoxicity and find it to exhibit potent, broad-spectrum anticancer activities. These results highlight the power of MoA-profiling technologies in repurposing old drugs for new targets. In addition, we identify an operon that confers TDA resistance to the producing marine bacteria. Bioinformatic and biochemical analyses of these genes lead to a previously unknown metabolic link between TDA/acid resistance and the γ-glutamyl cycle. The implications of this resistance mechanism in the context of the algal-bacterial symbiosis are discussed.

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Frommlet, Jörg C., Maria L. Sousa, Artur Alves, Sandra I. Vieira, David J. Suggett, and João Serôdio. "Coral symbiotic algae calcifyex hospitein partnership with bacteria." Proceedings of the National Academy of Sciences 112, no. 19 (April 27, 2015): 6158–63. http://dx.doi.org/10.1073/pnas.1420991112.

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Dinoflagellates of the genusSymbiodiniumare commonly recognized as invertebrate endosymbionts that are of central importance for the functioning of coral reef ecosystems. However, the endosymbiotic phase withinSymbiodiniumlife history is inherently tied to a more cryptic free-living (ex hospite) phase that remains largely unexplored. Here we show that free-livingSymbiodiniumspp. in culture commonly form calcifying bacterial–algal communities that produce aragonitic spherulites and encase the dinoflagellates as endolithic cells. This process is driven bySymbiodiniumphotosynthesis but occurs only in partnership with bacteria. Our findings not only place dinoflagellates on the map of microbial–algal organomineralization processes but also point toward an endolithic phase in theSymbiodiniumlife history, a phenomenon that may provide new perspectives on the biology and ecology ofSymbiodiniumspp. and the evolutionary history of the coral–dinoflagellate symbiosis.

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Lin, Chao, Peng Cao, Xiaolin Xu, and Bangce Ye. "Algal-Bacterial Symbiosis System Treating High-Load Printing and Dyeing Wastewater in Continuous-Flow Reactors under Natural Light." Water 11, no. 3 (March 5, 2019): 469. http://dx.doi.org/10.3390/w11030469.

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This study investigated the symbiotic structure relationship between mixed algae andactivated sludge while treating high-load printing and dyeing wastewater under natural light. Theeffects of hydraulic retention time (HRT) (12 h, 16 h and 20 h) and aeration rate (0.1–0.15, 0.4–0.5and 0.7–0.8 L/min) on algal–bacterial symbiosis (ABS) and conventional activated sludge (CAS)systems. Experimental results showed that the ABS system exhibited the best removal performancefor chemical oxygen demand (COD), ammonia nitrogen (NH4+-N) and total phosphorus (TP),which was increased by 12.5%, 23.1% and 10.5%, respectively, and reduced colour 80 timescompared with the printing and dyeing wastewater treatment plant. Algae growth could bepromoted under lower dissolved oxygen (DO), and the addition of algae could provide more DO tothe ABS system. The particle size distribution of sludge in the ABS system was stable, whichguaranteed a stable treatment effect. In addition, the COD and colour could be further degradedunder the conditions of no external carbon source and longer HRT. It is expected that the presentstudy will provide a foundation for the practical application of the ABS system, and new insightsfor the treatment of printing and dyeing wastewater.

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Van Den Hende, S., H. Vervaeren, and N. Boon. "Industrial symbiosis: C, N and P scavenging from sewage and flue gas with algal bacterial flocs." Journal of Biotechnology 150 (November 2010): 278. http://dx.doi.org/10.1016/j.jbiotec.2010.09.200.

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Ashen, Jon B., and Lynda J. Goff. "Galls on the marine red algaPrionitis lanceolata(Halymeniaceae): specific induction and subsequent development of an algal-bacterial symbiosis." American Journal of Botany 85, no. 12 (December 1998): 1710–21. http://dx.doi.org/10.2307/2446505.

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Medina, M., and U. Neis. "Symbiotic algal bacterial wastewater treatment: effect of food to microorganism ratio and hydraulic retention time on the process performance." Water Science and Technology 55, no. 11 (June 1, 2007): 165–71. http://dx.doi.org/10.2166/wst.2007.351.

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Algal incorporation into the biomass is important in an innovative wastewater treatment that exploits the symbiosis between bacterial activated sludge and microalgae (Chlorella vulgaris sp. Hamburg). It allows a good and easy algae separation by means of clarification. The effect of process parameters food to microorganisms ratio (F/M) and hydraulic retention time (HRT) on the process performance, evaluated by settleability, microalgae incorporation to biomass and nutrient removal, was studied. HRT hinted at a significant influence in the growth rate of algae, while F/M turned out to be important for stability when algae are incorporated into the biomass. This parameter also affects the total nitrogen removal of the treatment. Stable flocs with incorporated algae and supernatants with low free swimming algae concentrations were obtained at high HRT and low F/M values.

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Li, Bing, Wenli Huang, Chao Zhang, Sisi Feng, Zhenya Zhang, Zhongfang Lei, and Norio Sugiura. "Effect of TiO 2 nanoparticles on aerobic granulation of algal–bacterial symbiosis system and nutrients removal from synthetic wastewater." Bioresource Technology 187 (July 2015): 214–20. http://dx.doi.org/10.1016/j.biortech.2015.03.118.

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Sayara, Tahseen, Saed Khayat, Jebreel Saleh, Nawaf Abu-Khalaf, and Peter van der Steen. "Algal–bacterial symbiosis for nutrients removal from wastewater: The application of multivariate data analysis for process monitoring and control." Environmental Technology & Innovation 23 (August 2021): 101548. http://dx.doi.org/10.1016/j.eti.2021.101548.

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Bird, Clare, Kate F. Darling, Ann D. Russell, Catherine V. Davis, Jennifer Fehrenbacher, Andrew Free, Michael Wyman, and Bryne T. Ngwenya. "Cyanobacterial endobionts within a major marine planktonic calcifier (<i>Globigerina bulloides</i>, Foraminifera) revealed by 16S rRNA metabarcoding." Biogeosciences 14, no. 4 (February 28, 2017): 901–20. http://dx.doi.org/10.5194/bg-14-901-2017.

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Abstract. We investigated the possibility of bacterial symbiosis in Globigerina bulloides, a palaeoceanographically important, planktonic foraminifer. This marine protist is commonly used in micropalaeontological investigations of climatically sensitive subpolar and temperate water masses as well as wind-driven upwelling regions of the world's oceans. G. bulloides is unusual because it lacks the protist algal symbionts that are often found in other spinose species. In addition, it has a large offset in its stable carbon and oxygen isotopic compositions compared to other planktonic foraminifer species, and also that predicted from seawater equilibrium. This is suggestive of novel differences in ecology and life history of G. bulloides, making it a good candidate for investigating the potential for bacterial symbiosis as a contributory factor influencing shell calcification. Such information is essential to evaluate fully the potential response of G. bulloides to ocean acidification and climate change. To investigate possible ecological interactions between G. bulloides and marine bacteria, 18S rRNA gene sequencing, fluorescence microscopy, 16S rRNA gene metabarcoding and transmission electron microscopy (TEM) were performed on individual specimens of G. bulloides (type IId) collected from two locations in the California Current. Intracellular DNA extracted from five G. bulloides specimens was subjected to 16S rRNA gene metabarcoding and, remarkably, 37–87 % of all 16S rRNA gene sequences recovered were assigned to operational taxonomic units (OTUs) from the picocyanobacterium Synechococcus. This finding was supported by TEM observations of intact Synechococcus cells in both the cytoplasm and vacuoles of G. bulloides. Their concentrations were up to 4 orders of magnitude greater inside the foraminifera than those reported for the California Current water column and approximately 5 % of the intracellular Synechococcus cells observed were undergoing cell division. This suggests that Synechococcus is an endobiont of G. bulloides type IId, which is the first report of a bacterial endobiont in the planktonic foraminifera. We consider the potential roles of Synechococcus and G. bulloides within the relationship and the need to determine how widespread the association is within the widely distributed G. bulloides morphospecies. The possible influence of Synechococcus respiration on G. bulloides shell geochemistry is also explored.

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Tang, Cong-Cong, Yu Tian, Zhang-Wei He, Wei Zuo, and Jun Zhang. "Performance and mechanism of a novel algal-bacterial symbiosis system based on sequencing batch suspended biofilm reactor treating domestic wastewater." Bioresource Technology 265 (October 2018): 422–31. http://dx.doi.org/10.1016/j.biortech.2018.06.033.

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Tang, Cong-Cong, Wei Zuo, Yu Tian, Ni Sun, Zhen-Wei Wang, and Jun Zhang. "Effect of aeration rate on performance and stability of algal-bacterial symbiosis system to treat domestic wastewater in sequencing batch reactors." Bioresource Technology 222 (December 2016): 156–64. http://dx.doi.org/10.1016/j.biortech.2016.09.123.

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Kenny, Nathan J., Bruna Plese, Ana Riesgo, and Valeria B. Itskovich. "Symbiosis, Selection, and Novelty: Freshwater Adaptation in the Unique Sponges of Lake Baikal." Molecular Biology and Evolution 36, no. 11 (June 27, 2019): 2462–80. http://dx.doi.org/10.1093/molbev/msz151.

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Abstract Freshwater sponges (Spongillida) are a unique lineage of demosponges that secondarily colonized lakes and rivers and are now found ubiquitously in these ecosystems. They developed specific adaptations to freshwater systems, including the ability to survive extreme thermal ranges, long-lasting dessication, anoxia, and resistance to a variety of pollutants. Although spongillids have colonized all freshwater systems, the family Lubomirskiidae is endemic to Lake Baikal and plays a range of key roles in this ecosystem. Our work compares the genomic content and microbiome of individuals of three species of the Lubomirskiidae, providing hypotheses for how molecular evolution has allowed them to adapt to their unique environments. We have sequenced deep (>92% of the metazoan “Benchmarking Universal Single-Copy Orthologs” [BUSCO] set) transcriptomes from three species of Lubomirskiidae and a draft genome resource for Lubomirskia baikalensis. We note Baikal sponges contain unicellular algal and bacterial symbionts, as well as the dinoflagellate Gyrodinium. We investigated molecular evolution, gene duplication, and novelty in freshwater sponges compared with marine lineages. Sixty one orthogroups have consilient evidence of positive selection. Transporters (e.g., zinc transporter-2), transcription factors (aristaless-related homeobox), and structural proteins (e.g. actin-3), alongside other genes, are under strong evolutionary pressure in freshwater, with duplication driving novelty across the Spongillida, but especially in the Lubomirskiidae. This addition to knowledge of freshwater sponge genetics provides a range of tools for understanding the molecular biology and, in the future, the ecology (e.g., colonization and migration patterns) of these key species.

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Setiabudi, Gede Iwan, Dietriech G. Bengen, Ocky Karna Radjasa, and Hefni Effendi. "Preliminary study of algasidal activities of the episymbiont bacterial consortium from Enhalus acoroides." Advances in Tropical Biodiversity and Environmental Sciences 2, no. 2 (December 10, 2018): 21. http://dx.doi.org/10.24843/atbes.2018.v02.i02.p02.

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Seagrass symbiotic bacteria have various functions, one of which is as algaside. There are 2 types of symbionts namely endosymbiont and episymbiont. This study aims to test the initial activity of algaside episymbiont Enhalus acoroides on diatome and dinoflagellate group plankton. The method used for testing is Mixed Algal-bacterial cultures. On media that has been overgrown with algae will be inoculated with episymbiont bacterial consortium E. acoroides. The results of the bacterial consortium research have not shown significant algaside activity. But, on Nitschia sp. showed significant algaside activity. This mean specific activity in the compound or mechanism used as algaside.

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Ashen, Jon B., and Lynda J. Goff. "Molecular and Ecological Evidence for Species Specificity and Coevolution in a Group of Marine Algal-Bacterial Symbioses." Applied and Environmental Microbiology 66, no. 7 (July 1, 2000): 3024–30. http://dx.doi.org/10.1128/aem.66.7.3024-3030.2000.

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ABSTRACT The phylogenetic relationships of bacterial symbionts from three gall-bearing species in the marine red algal genusPrionitis (Rhodophyta) were inferred from 16S rDNA sequence analysis and compared to host phylogeny also inferred from sequence comparisons (nuclear ribosomal internal-transcribed-spacer region). Gall formation has been described previously on two species ofPrionitis, P. lanceolata (from central California) and P. decipiens (from Peru). This investigation reports gall formation on a third related host,Prionitis filiformis. Phylogenetic analyses based on sequence comparisons place the bacteria as a single lineage within theRoseobacter grouping of the α subclass of the divisionProteobacteria (99.4 to 98.25% sequence identity among phylotypes). Comparison of symbiont and host molecular phylogenies confirms the presence of three gall-bearing algal lineages and is consistent with the hypothesis that these red seaweeds and their bacterial symbionts are coevolving. The species specificity of these associations was investigated in nature by whole-cell hybridization of gall bacteria and in the laboratory by using cross-inoculation trials. Whole-cell in situ hybridization confirmed that a single bacterial symbiont phylotype is present in galls on each host. In laboratory trials, bacterial symbionts were incapable of inducing galls on alternate hosts (including two non-gall-bearing species). Symbiont-host specificity in Prionitis gall formation indicates an effective ecological separation between these closely related symbiont phylotypes and provides an example of a biological context in which to consider the organismic significance of 16S rDNA sequence variation.

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Ngugi, David Kamanda, Sou Miyake, Matt Cahill, Manikandan Vinu, Timothy J. Hackmann, Jochen Blom, Matthew D. Tietbohl, Michael L. Berumen, and Ulrich Stingl. "Genomic diversification of giant enteric symbionts reflects host dietary lifestyles." Proceedings of the National Academy of Sciences 114, no. 36 (August 23, 2017): E7592—E7601. http://dx.doi.org/10.1073/pnas.1703070114.

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Herbivorous surgeonfishes are an ecologically successful group of reef fish that rely on marine algae as their principal food source. Here, we elucidated the significance of giant enteric symbionts colonizing these fishes regarding their roles in the digestive processes of hosts feeding predominantly on polysiphonous red algae and brown Turbinaria algae, which contain different polysaccharide constituents. Using metagenomics, single-cell genomics, and metatranscriptomic analyses, we provide evidence of metabolic diversification of enteric microbiota involved in the degradation of algal biomass in these fishes. The enteric microbiota is also phylogenetically and functionally simple relative to the complex lignocellulose-degrading microbiota of terrestrial herbivores. Over 90% of the enzymes for deconstructing algal polysaccharides emanate from members of a single bacterial lineage, “Candidatus Epulopiscium” and related giant bacteria. These symbionts lack cellulases but encode a distinctive and lineage-specific array of mostly intracellular carbohydrases concurrent with the unique and tractable dietary resources of their hosts. Importantly, enzymes initiating the breakdown of the abundant and complex algal polysaccharides also originate from these symbionts. These are also highly transcribed and peak according to the diel lifestyle of their host, further supporting their importance and host–symbiont cospeciation. Because of their distinctive genomic blueprint, we propose the classification of these giant bacteria into three candidate genera. Collectively, our findings show that the acquisition of metabolically distinct “Epulopiscium” symbionts in hosts feeding on compositionally varied algal diets is a key niche-partitioning driver in the nutritional ecology of herbivorous surgeonfishes.

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许, 翔健. "The Interactions of Algal-Bacterial Symbiotic System and Its Effects on Wastewater Treatment." Water pollution and treatment 07, no. 01 (2019): 11–17. http://dx.doi.org/10.12677/wpt.2019.71002.

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Muñoz, R., C. Rolvering, B. Guieysse, and B. Mattiasson. "Photosynthetically oxygenated acetonitrile biodegradation by an algal-bacterial microcosm: a pilot-scale study." Water Science and Technology 51, no. 12 (June 1, 2005): 261–65. http://dx.doi.org/10.2166/wst.2005.0479.

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A 43-L column photobioreactor was tested for the treatment of acetonitrile using a symbiotic consortium consisting of a Chlorella sorokiniana strain and a Comamonas strain. Complete biodegradation of 1 g acetonitrile/l was achieved in 79 hours under continuous illumination at 500 μE/m2 s and 26 °C. When the photobioreactor was operated at 26 °C under a 14/10 hours light/dark illumination regime at 500 μE/m2 s, complete mineralization of 1 g acetonitrile/l was achieved in 111 hours. However, when acetonitrile was supplied at 2 g/l, the biodegradation process was severely inhibited by the increase of pH and NH4+ concentration during cultivation. In addition to saving energy for aeration, the microalgae assimilated 33% of the NH4+ released during acetonitrile biodegradation, which significantly reduces the need for subsequent nitrogen removal.

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Martin, Makenna M., Christina A. Kellogg, and Pamela Hallock. "Microbial Associations of Four Species of Algal Symbiont-bearing Foraminifers from the Florida Reef Tract, Usa." Journal of Foraminiferal Research 49, no. 2 (April 18, 2019): 178–90. http://dx.doi.org/10.2113/gsjfr.49.2.178.

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Abstract While microbiome research is a rapidly expanding field of study, relatively little is known of the microbiomes associated with Foraminifera. This preliminary study investigated microbes associated with four species of Foraminifera, representing two taxonomic orders, which host three kinds of algal endosymbionts. A major objective was to explore potential influences on the microbiome composition, including phylogenetic relatedness among the host species, similarities in algal symbionts hosted, and environmental conditions from which the specimens were collected. Samples examined from two locations along the middle Florida Keys reef tract included 45 foraminiferal specimens and four environmental samples. Bacterial DNA extraction from individual specimens was followed by amplification and amplicon sequencing of the V4 variable region of the 16S rRNA gene; results were obtained from 21 specimens. The Order Miliolida, Family Soritidae, was represented by 5–8 specimens of each of three species: Archaias angulatus and Cyclorbiculina compressa, which both host chlorophyte symbionts, and Sorites orbiculus, which hosts dinoflagellate symbionts. Three Ar. angulatus specimens from which the microbiome was successfully sequenced shared 177 OTUs. Six C. compressa specimens successfully sequenced shared 58 OTUs, of which 31 were also shared by the three specimens of Ar. angulatus. Four successfully sequenced S. orbiculus specimens shared 717 unique OTUs. The 13 soritid specimens shared 26 OTUs, 23 of which represented Proteobacteria, predominantly of the bacterial family Rhodobacteraceae. The fourth foraminiferal species, Amphistegina gibbosa (Order Rotaliida) hosts diatom endosymbionts. Bacterial DNA extraction was attempted on 16 Am. gibbosa, including both normal-appearing and partly-bleached specimens. Only six OTUs, four of which represented Proteobacteria, were found in all eight specimens successfully sequenced. The partly bleached specimens shared nearly twice as many unique microbial OTUs (32) as the normal-appearing specimens (19). All Am. gibbosa specimens shared only four microbial OTUs with the soritid species, three of which may have been contaminants, indicating minimal commonality between the microbiomes of Am. gibbosa and the soritid taxa.

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Sytnikov, D., N. Vorobey, and S. Kots. "Physiological reaction of legume plants to inoculation with algal-rhizobial associations." Acta Agronomica Hungarica 57, no. 2 (June 1, 2009): 239–44. http://dx.doi.org/10.1556/aagr.57.2009.2.15.

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The physiological reaction of legume plants to inoculation with algal-rhizobial associations was studied, based on the nodule bacteria, their Tn5 mutants and the cyanobacterium Nostoc punctiforme . It was shown that binary inoculation with rhizobia and cyanobacteria may have a positive effect if the inoculation agents and their ratio are correctly chosen. The data obtained on the effect of complex bacterization on the development and productivity of plants under legume-rhizobial symbiotic conditions indicate the prospects of bacterial preparations based on cyanobacteria and rhizobia, including their genetically modified strains.

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Klut, M. E., and J. G. Stockner. "Picoplankton Associations in an Ultra-Oligotrophic Lake on Vancouver Island, British Columbia." Canadian Journal of Fisheries and Aquatic Sciences 48, no. 6 (June 1, 1991): 1092–99. http://dx.doi.org/10.1139/f91-129.

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Epiphytic associations or "microaggregates" of picoplankton with larger phytoplankton in Sproat Lake, British Columbia, occurred in the epilimnion throughout the 1-yr study, but were most frequently seen at times of severe nutrient limitation in summer and autumn. Both bacterial and algal picoplankton epiphytes were attached to the cell surface of algal hosts by either fine protrusions or by their fibrillar extracellular matrix (glycocalyx). This surface coat increased in thickness as ambient nutrient concentrations became limiting, and harboured a range of heterogeneous organic and inorganic particles and phytoplankters. The phytoplanktonic host cells for these picoplankton associations included filamentous cyanobacteria, dinoflagellates, chlorophytes, coccolithophores, and diatoms. Under controlled nutrient-depleted conditions, the filamentous nitrogen-fixing cyanobacterium Anabaena flos-aquae became a common host of chroococcoid cyanobacterium. Some picoplankters were endophytic within the cytoplasm and vacuoles of protozoa and microflagellates, serving either as prey or as symbionts. These associations are thought to facilitate rapid carbon and nutrient recycling in pelagic ecosystems.

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Moondra, Nandini, Namrata D. Jariwala, and Robin A. Christian. "MICROALGAL-BACTERIAL CONSORTIA: AN ALLURING AND NOVEL APPROACH FOR DOMESTIC WASTEWATER TREATMENT." Water Conservation and Management 4, no. 1 (October 1, 2020): 51–56. http://dx.doi.org/10.26480/wcm.01.2020.51.56.

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The algal-bacterial process has received more attention in the present scenario as a new low-cost method towards pollutant removal from wastewater because symbiotic relationship between algae and bacteria is efficient when compared to traditional secondary treatments. The present work evaluated the optimum concentration of microalgal-bacterial consortia for significant reductions in physicochemical parameters of raw domestic wastewater. In the study, three different concentrations (20%, 30% and 40%) of microalgal-bacterial consortia were studied at 8 hours and 16 hours HRT. Among the different concentrations of consortia studied, 30% consortia gave maximum removal efficiency at both the HRTs. The maximum removal efficiency of phosphate, ammonia, BOD and COD was about 99.79%, 94.85%, 89.02% and 88.96%, respectively, at 8 hours HRT. However, at 16 hours, HRT maximum removal efficiency observed was 97.40%, 94.05%, 83.52% and 88.40% for phosphate, ammonia, BOD and COD respectively. The study depicts that microalgal-bacterial consortia can efficiently remediate nutrients and organic matter from domestic wastewater in both cases when sunlight was ample and even with minimal / no sunlight; hence this system can work effectively throughout the day with much lesser HRT and higher removal efficiency.

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Lee, Young-Shin, and Gee-Bong Han. "Complete reduction of highly concentrated contaminants in piggery waste by a novel process scheme with an algal-bacterial symbiotic photobioreactor." Journal of Environmental Management 177 (July 2016): 202–12. http://dx.doi.org/10.1016/j.jenvman.2016.04.025.

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Karimi, Elham, Enora Geslain, Arnaud Belcour, Clémence Frioux, Méziane Aïte, Anne Siegel, Erwan Corre, and Simon M. Dittami. "Robustness analysis of metabolic predictions in algal microbial communities based on different annotation pipelines." PeerJ 9 (May 6, 2021): e11344. http://dx.doi.org/10.7717/peerj.11344.

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Animals, plants, and algae rely on symbiotic microorganisms for their development and functioning. Genome sequencing and genomic analyses of these microorganisms provide opportunities to construct metabolic networks and to analyze the metabolism of the symbiotic communities they constitute. Genome-scale metabolic network reconstructions rest on information gained from genome annotation. As there are multiple annotation pipelines available, the question arises to what extent differences in annotation pipelines impact outcomes of these analyses. Here, we compare five commonly used pipelines (Prokka, MaGe, IMG, DFAST, RAST) from predicted annotation features (coding sequences, Enzyme Commission numbers, hypothetical proteins) to the metabolic network-based analysis of symbiotic communities (biochemical reactions, producible compounds, and selection of minimal complementary bacterial communities). While Prokka and IMG produced the most extensive networks, RAST and DFAST networks produced the fewest false positives and the most connected networks with the fewest dead-end metabolites. Our results underline differences between the outputs of the tested pipelines at all examined levels, with small differences in the draft metabolic networks resulting in the selection of different microbial consortia to expand the metabolic capabilities of the algal host. However, the consortia generated yielded similar predicted producible compounds and could therefore be considered functionally interchangeable. This contrast between selected communities and community functions depending on the annotation pipeline needs to be taken into consideration when interpreting the results of metabolic complementarity analyses. In the future, experimental validation of bioinformatic predictions will likely be crucial to both evaluate and refine the pipelines and needs to be coupled with increased efforts to expand and improve annotations in reference databases.

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Khan, M. A., and S. I. Ahmad. "Performance Evaluation of Pilot Waste Stabilization Ponds in Subtropical Region." Water Science and Technology 26, no. 7-8 (October 1, 1992): 1717–28. http://dx.doi.org/10.2166/wst.1992.0615.

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This research investigation was aimed at demonstrating the technical feasibility of facultative waste stabilization ponds under the climatic conditions of subtropical region. A pilot plant was designed and constructed at the Karachi University Campus for the treatment of domestic wastewater. An intensive analytical programme was followed for ten months for evaluating performance efficiency of the facultative ponding system. The algal-bacterial symbiotic system performed satisfactorily and provided effluent with total BOD5 ranging between 26-76 mg/L, total COD ranging between 59-197 mg/L, TKN ranging between 5.35-47.82 mg/L, NH3-N ranging between 0.23-28.98 mg/L, and PO4-P between 1.41-6.76 mg/L. The maximum efficiency achieved for the removal of coliform, fecal coliform and fecal streptococci was 99.99%. The study demonstrated that high BOD5 loading of 507 kg/ha d was possible without deteriorating the quality of performance. It was particularly observed that wind velocity had a pronounced effect on the overall efficiency of the system. It was concluded that facultative ponding system is strongly feasible for this part of the world for the treatment of wastewater.

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Cervino, James M., Raymond L. Hayes, Shawn W. Polson, Sara C. Polson, Thomas J. Goreau, Robert J. Martinez, and Garriet W. Smith. "Relationship of Vibrio Species Infection and Elevated Temperatures to Yellow Blotch/Band Disease in Caribbean Corals." Applied and Environmental Microbiology 70, no. 11 (November 2004): 6855–64. http://dx.doi.org/10.1128/aem.70.11.6855-6864.2004.

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ABSTRACT The bacterial and temperature factors leading to yellow blotch/band disease (YBD), which affects the major reef-building Caribbean corals Montastrea spp., have been investigated. Groups of bacteria isolated from affected corals and inoculated onto healthy corals caused disease signs similar to those of YBD. The 16S rRNA genes from these bacteria were sequenced and found to correspond to four Vibrio spp. Elevating the water temperature notably increased the rate of spread of YBD on inoculated corals and induced greater coral mortality. YBD-infected corals held at elevated water temperatures had 50% lower zooxanthella densities, 80% lower division rates, and a 75% decrease in chlorophyll a and c 2 pigments compared with controls. Histological sections indicated that the algal pyrenoid was fragmented into separate segments, along with a reconfiguration and swelling of the zooxanthellae, as well as vacuolization. YBD does not appear to produce the same physiological response formerly observed in corals undergoing temperature-related bleaching. Evidence indicates that YBD affects primarily the symbiotic algae rather than coral tissue.

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Barnet, YM, PC Catt, and DH Hearne. "Biological Nitrogen Fixation and Root-Nodule Bacteria (Rhizobium Sp. and Bradyrhizobium Sp.) In Two Rehabilitating Sand Dune Areas Planted With Acacia Spp." Australian Journal of Botany 33, no. 5 (1985): 595. http://dx.doi.org/10.1071/bt9850595.

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This paper reports a study of biological nitrogen fixation in two sand dune regions of New South Wales where planted Acacia spp. had been used in revegetation programmes. At one location (Bridge Hill Ridge), natural regrowth had produced a complex plant community, and native legumes in addition to the planted acacias were present. The other area (Wanda Beach) was a grossly disturbed site which contained only the planted species. Symbiotic fixation in association with Australian legumes occurred at both locations at rates within the range reported by other authors. Distinct seasonal changes were apparent, with higher activities in the cooler months. The legume association seemed the only source of biologically fixed nitrogen at Bridge Hill Ridge, but at Wanda Beach cyanobacteria in an algal mat also made a contribution. Fast and slow-growing bacterial strains were obtained from root nodules of native legumes at both sites and were classed as Rhizobium sp. and Bradyrhizobium sp., respectively. This division was supported by the pattern of serological affinities of the isolates and by differences in their protein profiles demonstrated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Two atypical types of root-nodule bacteria were found at Bridge Hill Ridge: non-nodulating, fast-growing isolates and an abnormally slow-growing Bradyrhizobium sp.

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Fernández-Brime, Samantha, Lucia Muggia, Stefanie Maier, Martin Grube, and Mats Wedin. "Bacterial communities in an optional lichen symbiosis are determined by substrate, not algal photobionts." FEMS Microbiology Ecology 95, no. 3 (January 22, 2019). http://dx.doi.org/10.1093/femsec/fiz012.

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Grimm, Maria, Martin Grube, Ulf Schiefelbein, Daniela Zühlke, Jörg Bernhardt, and Katharina Riedel. "The Lichens’ Microbiota, Still a Mystery?" Frontiers in Microbiology 12 (March 30, 2021). http://dx.doi.org/10.3389/fmicb.2021.623839.

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Lichens represent self-supporting symbioses, which occur in a wide range of terrestrial habitats and which contribute significantly to mineral cycling and energy flow at a global scale. Lichens usually grow much slower than higher plants. Nevertheless, lichens can contribute substantially to biomass production. This review focuses on the lichen symbiosis in general and especially on the model species Lobaria pulmonaria L. Hoffm., which is a large foliose lichen that occurs worldwide on tree trunks in undisturbed forests with long ecological continuity. In comparison to many other lichens, L. pulmonaria is less tolerant to desiccation and highly sensitive to air pollution. The name-giving mycobiont (belonging to the Ascomycota), provides a protective layer covering a layer of the green-algal photobiont (Dictyochloropsis reticulata) and interspersed cyanobacterial cell clusters (Nostoc spec.). Recently performed metaproteome analyses confirm the partition of functions in lichen partnerships. The ample functional diversity of the mycobiont contrasts the predominant function of the photobiont in production (and secretion) of energy-rich carbohydrates, and the cyanobiont’s contribution by nitrogen fixation. In addition, high throughput and state-of-the-art metagenomics and community fingerprinting, metatranscriptomics, and MS-based metaproteomics identify the bacterial community present on L. pulmonaria as a surprisingly abundant and structurally integrated element of the lichen symbiosis. Comparative metaproteome analyses of lichens from different sampling sites suggest the presence of a relatively stable core microbiome and a sampling site-specific portion of the microbiome. Moreover, these studies indicate how the microbiota may contribute to the symbiotic system, to improve its health, growth and fitness.

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Rao, Minxi, Brian C. Smith, and Michael A. Marletta. "Nitric Oxide Mediates Biofilm Formation and Symbiosis in Silicibacter sp. Strain TrichCH4B." mBio 6, no. 3 (May 5, 2015). http://dx.doi.org/10.1128/mbio.00206-15.

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ABSTRACT Nitric oxide (NO) plays an important signaling role in all domains of life. Many bacteria contain a heme-nitric oxide/oxygen binding (H-NOX) protein that selectively binds NO. These H-NOX proteins often act as sensors that regulate histidine kinase (HK) activity, forming part of a bacterial two-component signaling system that also involves one or more response regulators. In several organisms, NO binding to the H-NOX protein governs bacterial biofilm formation; however, the source of NO exposure for these bacteria is unknown. In mammals, NO is generated by the enzyme nitric oxide synthase (NOS) and signals through binding the H-NOX domain of soluble guanylate cyclase. Recently, several bacterial NOS proteins have also been reported, but the corresponding bacteria do not also encode an H-NOX protein. Here, we report the first characterization of a bacterium that encodes both a NOS and H-NOX, thus resembling the mammalian system capable of both synthesizing and sensing NO. We characterized the NO signaling pathway of the marine alphaproteobacterium Silicibacter sp. strain TrichCH4B, determining that the NOS is activated by an algal symbiont, Trichodesmium erythraeum. NO signaling through a histidine kinase-response regulator two-component signaling pathway results in increased concentrations of cyclic diguanosine monophosphate, a key bacterial second messenger molecule that controls cellular adhesion and biofilm formation. Silicibacter sp. TrichCH4B biofilm formation, activated by T. erythraeum, may be an important mechanism for symbiosis between the two organisms, revealing that NO plays a previously unknown key role in bacterial communication and symbiosis. IMPORTANCE Bacterial nitric oxide (NO) signaling via heme-nitric oxide/oxygen binding (H-NOX) proteins regulates biofilm formation, playing an important role in protecting bacteria from oxidative stress and other environmental stresses. Biofilms are also an important part of symbiosis, allowing the organism to remain in a nutrient-rich environment. In this study, we show that in Silicibacter sp. strain TrichCH4B, NO mediates symbiosis with the alga Trichodesmium erythraeum, a major marine diazotroph. In addition, Silicibacter sp. TrichCH4B is the first characterized bacteria to harbor both the NOS and H-NOX proteins, making it uniquely capable of both synthesizing and sensing NO, analogous to mammalian NO signaling. Our study expands current understanding of the role of NO in bacterial signaling, providing a novel role for NO in bacterial communication and symbiosis.

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Röthig, Till, Giulia Puntin, Jane C. Y. Wong, Alfred Burian, Wendy McLeod, and David M. Baker. "Holobiont nitrogen control and its potential for eutrophication resistance in an obligate photosymbiotic jellyfish." Microbiome 9, no. 1 (June 2, 2021). http://dx.doi.org/10.1186/s40168-021-01075-0.

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Abstract Background Marine holobionts depend on microbial members for health and nutrient cycling. This is particularly evident in cnidarian-algae symbioses that facilitate energy and nutrient acquisition. However, this partnership is highly sensitive to environmental change—including eutrophication—that causes dysbiosis and contributes to global coral reef decline. Yet, some holobionts exhibit resistance to dysbiosis in eutrophic environments, including the obligate photosymbiotic scyphomedusa Cassiopea xamachana. Methods Our aim was to assess the mechanisms in C. xamachana that stabilize symbiotic relationships. We combined labelled bicarbonate (13C) and nitrate (15N) with metabarcoding approaches to evaluate nutrient cycling and microbial community composition in symbiotic and aposymbiotic medusae. Results C-fixation and cycling by algal Symbiodiniaceae was essential for C. xamachana as even at high heterotrophic feeding rates aposymbiotic medusae continuously lost weight. Heterotrophically acquired C and N were readily shared among host and algae. This was in sharp contrast to nitrate assimilation by Symbiodiniaceae, which appeared to be strongly restricted. Instead, the bacterial microbiome seemed to play a major role in the holobiont’s DIN assimilation as uptake rates showed a significant positive relationship with phylogenetic diversity of medusa-associated bacteria. This is corroborated by inferred functional capacity that links the dominant bacterial taxa (~90 %) to nitrogen cycling. Observed bacterial community structure differed between apo- and symbiotic C. xamachana putatively highlighting enrichment of ammonium oxidizers and nitrite reducers and depletion of nitrogen-fixers in symbiotic medusae. Conclusion Host, algal symbionts, and bacterial associates contribute to regulated nutrient assimilation and cycling in C. xamachana. We found that the bacterial microbiome of symbiotic medusae was seemingly structured to increase DIN removal and enforce algal N-limitation—a mechanism that would help to stabilize the host-algae relationship even under eutrophic conditions.

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Hasan, M., Md Khalekuzzaman, M. Alamgir, P. Datta, and S. B. Kabir. "A new energy-positive technological approach for wastewater treatment and bioenergy generation using a photo anoxic baffled reactor (PABR)." International Journal of Environmental Science and Technology, February 15, 2021. http://dx.doi.org/10.1007/s13762-021-03168-7.

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AbstractThis study proposed a new energy-positive technological approach for wastewater treatment and bioenergy generation using an algal–bacterial symbiosis system in a photo anoxic baffled reactor (PABR). The PABR consisted of a sedimentation chamber, four regular baffled chambers, and two floated filter media chambers. The PABR was operated in the presence of natural sunlight with an average intensity of 30 µmoles/m2/s. A wide range of ORP (−215 to 255 mV) data suggested that a suitable environment condition existed in the PABR for photosynthesis, nitrification, and denitrification. Simultaneous nitrification/denitrification (SND) was observed in the first three chambers, and microbial assimilation was governed in the last four chambers. An average biochemical oxygen demand (BOD), NH3–N, total nitrogen (TN), and PO43− removal efficiencies were more than 88, 48, 36, and 42%, respectively. Moreover, hydrothermal liquefaction (HTL) was carried out for sludge and microalgae samples for bioenergy (e.g., biocrude and biochar) conversion, where the sludge sample containing microalgae and bacteria was collected from PABR and microalgae sample was collected from photobioreactor. Finally, the Fourier transform infrared spectroscopy (FTIR) analysis was done for both biocrude and biochar derived from sludge and microalgae samples, and it was suggested that the biocrude and biochar derived from sludge sample were better than that of microalgae sample.

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Saravanan, A., P. Senthil Kumar, Sunita Varjani, S. Jeevanantham, P. R. Yaashikaa, P. Thamarai, B. Abirami, and Cynthia Susan George. "A Review on Algal-Bacterial Symbiotic System for Effective Treatment of Wastewater." Chemosphere, January 2021, 129540. http://dx.doi.org/10.1016/j.chemosphere.2021.129540.

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Randle, Janna L., Anny Cárdenas, Hagen M. Gegner, Maren Ziegler, and Christian R. Voolstra. "Salinity-Conveyed Thermotolerance in the Coral Model Aiptasia Is Accompanied by Distinct Changes of the Bacterial Microbiome." Frontiers in Marine Science 7 (November 25, 2020). http://dx.doi.org/10.3389/fmars.2020.573635.

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Coral bleaching, i.e., the loss of photosynthetic algal endosymbionts, caused by ocean warming is now among the main factors driving global reef decline, making the elucidation of factors that contribute to thermotolerance important. Recent studies implicate high salinity as a contributing factor in cnidarians, potentially explaining the high thermotolerance of corals from the Arabian Seas. Here we characterized bacterial community composition under heat stress at different salinities using the coral model Aiptasia. Exposure of two Aiptasia host-algal symbiont pairings (H2-SSB01 and CC7-SSA01) to ambient (25°C) and heat stress (34°C) temperatures at low (36 PSU), intermediate (39 PSU), and high (42 PSU) salinities showed that bacterial community composition at high salinity was significantly different, concomitant with reduced bleaching susceptibility in H2-SSB01, not observed in CC7-SSA01. Elucidation of bacteria that showed increased relative abundance at high salinity, irrespective of heat stress, revealed candidate taxa that could potentially contribute to the observed increased thermotolerance. We identified 4 (H2-SSB01) and 3 (CC7-SSA01) bacterial taxa belonging to the orders Alteromonadales (1 OTU), Oligoflexales (1 OTU), Rhizobiales (2 OTUs), and Rhodobacterales (2 OTUs), suggesting that only few bacterial taxa are potential contributors to an increase in thermal tolerance at high salinities. These taxa have previously been implicated in nitrogen and DMSP cycling, processes that are considered to affect thermotolerance. Our study demonstrates microbiome restructuring in symbiotic cnidarians under heat stress at different salinities. As such, it underlines how host-associated bacterial communities adapt to prevailing environmental conditions with putative consequences for the environmental stress tolerance of the emergent metaorganism.

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Parata, Lara, Shaun Nielsen, Xing Xing, Torsten Thomas, Suhelen Egan, and Adriana Vergés. "Age, gut location and diet impact the gut microbiome of a tropical herbivorous surgeonfish." FEMS Microbiology Ecology, November 19, 2019. http://dx.doi.org/10.1093/femsec/fiz179.

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Abstract Herbivorous fishes play important ecological roles in coral reefs by consuming algae that can otherwise outcompete corals, but we know little about the gut microbiota that facilitates this process. This study focussed on the gut microbiota of an ecologically important coral reef fish, the convict surgeonfish Acanthurus triostegus. We sought to understand how the microbiome of this species varies along its gastrointestinal tract and how it varies between juvenile and adult fish. Further, we examined if the bacteria associated with the diet consumed by juveniles contributes to the gut microbiota. 16S rRNA gene amplicon sequencing showed that bacterial communities associated with the midgut and hindgut regions were distinct between adults and juveniles, however, no significant differences were seen for gut wall samples. The microbiota associated with the epilithic algal food source was similar to that of the juvenile midgut and gut wall but differed from the microbiome of the hindgut. A core bacterial community including members of taxa Epulopiscium and Brevinemataceae was observed across all gastrointestinal and diet samples, suggesting that these bacterial symbionts can be acquired by juvenile convict surgeonfish horizontally via their diet and then are retained into adulthood.

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Journal articles on the topic 'Algal-bacterial symbiosis'

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