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Kuhlisch C, Shemi A, Barak-Gavish N, Schatz D, Vardi A. Algal blooms in the ocean: hot spots for chemically mediated microbial interactions. Nat Rev Microbiol 2024; 22:138-154. [PMID: 37833328 DOI: 10.1038/s41579-023-00975-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 09/14/2023] [Indexed: 10/15/2023]
Abstract
The cycling of major nutrients in the ocean is affected by large-scale phytoplankton blooms, which are hot spots of microbial life. Diverse microbial interactions regulate bloom dynamics. At the single-cell level, interactions between microorganisms are mediated by small molecules in the chemical crosstalk that determines the type of interaction, ranging from mutualism to pathogenicity. Algae interact with viruses, bacteria, parasites, grazers and other algae to modulate algal cell fate, and these interactions are dependent on the environmental context. Recent advances in mass spectrometry and single-cell technologies have led to the discovery of a growing number of infochemicals - metabolites that convey information - revealing the ability of algal cells to govern biotic interactions in the ocean. The diversity of infochemicals seems to account for the specificity in cellular response during microbial communication. Given the immense impact of algal blooms on biogeochemical cycles and climate regulation, a major challenge is to elucidate how microscale interactions control the fate of carbon and the recycling of major elements in the ocean. In this Review, we discuss microbial interactions and the role of infochemicals in algal blooms. We further explore factors that can impact microbial interactions and the available tools to decipher them in the natural environment.
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Affiliation(s)
- Constanze Kuhlisch
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Adva Shemi
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Noa Barak-Gavish
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
- Institute of Microbiology, ETH Zurich, Zurich, Switzerland
| | - Daniella Schatz
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel
| | - Assaf Vardi
- Department of Plant and Environmental Sciences, Weizmann Institute of Science, Rehovot, Israel.
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2
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Díaz-Alonso A, Rodríguez F, Riobó P, Álvarez-Salgado X, Teira E, Fernández E. Response of the toxic dinoflagellate Alexandrium minutum to exudates of the eelgrass Zostera marina. Harmful Algae 2024; 133:102605. [PMID: 38485446 DOI: 10.1016/j.hal.2024.102605] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/20/2023] [Revised: 01/15/2024] [Accepted: 02/20/2024] [Indexed: 03/19/2024]
Abstract
Biotic interactions are a key factor in the development of harmful algal blooms. Recently, a lower abundance of planktonic dinoflagellates has been reported in areas dominated by seagrass beds, suggesting a negative interaction between both groups of organisms. The interaction between planktonic dinoflagellates and marine phanerogams, as well as the way in which bacteria can affect this interaction, was studied in two experiments using a non-axenic culture of the toxic dinoflagellate Alexandrium minutum exposed to increasing additions of eelgrass (Zostera marina) exudates from old and young leaves and to the presence or absence of antibiotics. In these experiments, A. minutum abundance, growth rate and photosynthetic efficiency (Fv/Fm), as well as bacterial abundance, were measured every 48 h. Toxin concentration per cell was determined at the end of both experiments. Our results demonstrated that Z. marina exudates reduced A. minutum growth rate and, in one of the experiments, also the photosynthetic efficiency. These results are not an indirect effect mediated by the bacteria in the culture, although their growth modify the magnitude of the negative impact on the dinoflagellate growth rate. No clear pattern was observed in the variation of toxin production with the treatments.
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Affiliation(s)
| | - Francisco Rodríguez
- Centro Oceanográfico de Vigo, Instituto Español de Ocanografía, Consejo Superior de Investigaciones Científicas, Spain
| | - Pilar Riobó
- Instituto de Investigacións Mariñas, Consejo Superior de Investigaciones Científicas, Spain
| | - Xose Álvarez-Salgado
- Instituto de Investigacións Mariñas, Consejo Superior de Investigaciones Científicas, Spain
| | - Eva Teira
- Centro de Investigación Mariña, Universidade de Vigo, Vigo, Spain
| | - Emilio Fernández
- Centro de Investigación Mariña, Universidade de Vigo, Vigo, Spain
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Choi CJ, Jauzein C, Erdner DL. High-resolution phylogenetic analysis reveals long-term microbial dynamics and microdiversity in phytoplankton microbiome. J Eukaryot Microbiol 2023; 70:e12966. [PMID: 36756708 DOI: 10.1111/jeu.12966] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 11/16/2022] [Accepted: 01/26/2023] [Indexed: 02/10/2023]
Abstract
Phytoplankton-bacteria interactions represent the evolution of complex cross-kingdom networks requiring niche specialization of diverse microbes. Unraveling this co-evolutionary process has proven challenging because microbial partnerships are complex, and their assembly can be dynamic as well as scale- and taxon-dependent. Here, we monitored long-term experimental evolution of phytoplankton-bacteria interactions by reintroducing the intact microbiome into an axenized dinoflagellate Alexandrium tamarense to better understand microbiome assembly dynamics and how microbiome composition could shift and stabilize over 15 months. We examined host functioning by growth rate, photosynthetic capability, cell size, and other physiological signatures and compared it to associated microbial communities determined by 16S rRNA gene sequences. Our results showed that microbiome reconstitution did not restore the intact microbiome, instead a distinct microbial community shift to Roseobacter clade was observed in the re-established cultures. In-depth comparisons of microbial interactions revealed no apparent coupling between host physiology and specific bacterial taxa, indicating that highly represented, abundant taxa might not be essential for host functioning. The emergence of highly divergent Roseobacter clade sequences suggests fine-scale microbial dynamics driven by microdiversity could be potentially linked to host functioning. Collectively, our results indicate that functionally comparable microbiomes can be assembled from markedly different, highly diverse bacterial taxa in changing environments.
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Affiliation(s)
- Chang Jae Choi
- The University of Texas at Austin, Marine Science Institute, Port Aransas, Texas, USA.,Fort Lauderdale Research and Education Center, University of Florida, Davie, FL, USA
| | - Cecile Jauzein
- The University of Texas at Austin, Marine Science Institute, Port Aransas, Texas, USA.,Ifremer, Dynamiques des Ecosystèmes Côtiers (DYNECO), Laboratoire d'Ecologie Pélagique (PELAGOS), Plouzané, France
| | - Deana L Erdner
- The University of Texas at Austin, Marine Science Institute, Port Aransas, Texas, USA
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4
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Deng Y, Wang K, Hu Z, Hu Q, Tang YZ. Identification and implications of a core bacterial microbiome in 19 clonal cultures laboratory-reared for months to years of the cosmopolitan dinoflagellate Karlodinium veneficum. Front Microbiol 2022; 13:967610. [PMID: 36033882 PMCID: PMC9416233 DOI: 10.3389/fmicb.2022.967610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Accepted: 07/18/2022] [Indexed: 11/13/2022] Open
Abstract
Identification of a core microbiome (a group of taxa commonly present and consistently abundant in most samples of host populations) is important to capture the key microbes closely associated with a host population, as this process may potentially contribute to further revealing their spatial distribution, temporal stability, ecological influence, and even impacts on their host’s functions and fitness. The naked dinoflagellate Karlodinium veneficum is a cosmopolitan and toxic species, which is also notorious in forming harmful algal blooms (HABs) and causing massive fish-kills. Here we reported the core microbiome tightly associated with 19 strains of K. veneficum that were originally isolated from 6 geographic locations along the coast of China and from an estuary of Chesapeake Bay, United States, and have been maintained in the laboratory for several months to over 14 years. Using high-throughput metabarcoding of the partial 16S rRNA gene amplicons, a total of 1,417 prokaryotic features were detected in the entire bacterial microbiome, which were assigned to 17 phyla, 35 classes, 90 orders, 273 families, and 716 genera. Although the bacterial communities associated with K. veneficum cultures displayed heterogeneity in feature (sequences clustered at 100% sequence similarity) composition among strains, a core set of 6 genera were found persistent in their phycospheres, which could contribute up to 74.54% of the whole bacterial microbiome. Three γ-proteobacteria members of the “core,” namely, Alteromonas, Marinobacter, and Methylophaga, were the predominant core genera and made up 83.25% of the core bacterial microbiome. The other 3 core genera, Alcanivorax, Thalassospira, and Ponticoccus, are reported to preferably utilize hydrocarbons as sole or major source of carbon and energy, and two of which (Alcanivorax and Ponticoccus) are recognized as obligate hydrocarbonoclastic bacteria (OHCB). Since OHCB generally present in extremely low abundance in marine water and elevate their abundance mostly in petroleum-impacted water, our detection in K. veneficum cultures suggests that the occurrence of obligate and generalist hydrocarbon-degrading bacteria living with dinoflagellates may be more frequent in nature. Our work identified a core microbiome with stable association with the harmful alga K. veneficum and opened a window for further characterization of the physiological mechanisms and ecological implications for the dinoflagellate-bacteria association.
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Affiliation(s)
- Yunyan Deng
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China
- Laboratory of Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
- Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao, China
| | - Kui Wang
- Institute for Advanced Study, Shenzhen University, Shenzhen, China
| | - Zhangxi Hu
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China
- College of Fisheries, Guangdong Ocean University, Zhanjiang, China
| | - Qiang Hu
- Faculty of Synthetic Biology, CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institute of Advanced Technology, Chinese Academy of Sciences, Shenzhen, China
| | - Ying Zhong Tang
- CAS Key Laboratory of Marine Ecology and Environmental Sciences, Institute of Oceanology, Chinese Academy of Sciences, Qingdao, China
- Laboratory of Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao, China
- Center for Ocean Mega-Science, Chinese Academy of Sciences, Qingdao, China
- *Correspondence: Ying Zhong Tang,
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Hendriks KP, Bisschop K, Kortenbosch HH, Kavanagh JC, Larue AEA, Chee‐Chean P, Bonte D, Duijm EJ, Salles JF, Pigot AL, Richter Mendoza FJ, Schilthuizen M, Anderson MJ, Speksnijder AGCL, Etienne RS. Microbiome and environment explain the absence of correlations between consumers and their diet in Bornean microsnails. Ecology 2021; 102:e03237. [PMID: 33098661 PMCID: PMC7900957 DOI: 10.1002/ecy.3237] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/27/2020] [Accepted: 09/14/2020] [Indexed: 01/04/2023]
Abstract
Classical ecological theory posits that species partition resources such that each species occupies a unique resource niche. In general, the availability of more resources allows more species to co-occur. Thus, a strong relationship between communities of consumers and their resources is expected. However, correlations may be influenced by other layers in the food web, or by the environment. Here we show, by studying the relationship between communities of consumers (land snails) and individual diets (from seed plants), that there is in fact no direct, or at most a weak but negative, relationship. However, we found that the diversity of the individual microbiome positively correlates with both consumer community diversity and individual diet diversity in three target species. Moreover, these correlations were affected by various environmental variables, such as anthropogenic activity, habitat island size, and a possibly important nutrient source, guano runoff from nearby caves. Our results suggest that the microbiome and the environment explain the absence of correlations between diet and consumer community diversity. Hence, we advocate that microbiome inventories are routinely added to any community dietary analysis, which our study shows can be done with relatively little extra effort. Our approach presents the tools to quickly obtain an overview of the relationships between consumers and their resources. We anticipate our approach to be useful for ecologists and environmentalists studying different communities in a local food web.
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Affiliation(s)
- Kasper P. Hendriks
- Groningen Institute for Evolutionary Life SciencesUniversity of GroningenP.O. Box 11103Groningen9700 CCThe Netherlands
- Naturalis Biodiversity CenterDarwinweg 2Leiden2333CRThe Netherlands
- Biology Department, BotanyOsnabrück UniversityBarbarastr. 11Osnabrück49076Germany
| | - Karen Bisschop
- Groningen Institute for Evolutionary Life SciencesUniversity of GroningenP.O. Box 11103Groningen9700 CCThe Netherlands
- Terrestrial Ecology UnitGhent UniversityK.L. Ledeganckstraat 35Ghent9000Belgium
| | - Hylke H. Kortenbosch
- Groningen Institute for Evolutionary Life SciencesUniversity of GroningenP.O. Box 11103Groningen9700 CCThe Netherlands
| | - James C. Kavanagh
- Groningen Institute for Evolutionary Life SciencesUniversity of GroningenP.O. Box 11103Groningen9700 CCThe Netherlands
| | - Anaïs E. A. Larue
- Groningen Institute for Evolutionary Life SciencesUniversity of GroningenP.O. Box 11103Groningen9700 CCThe Netherlands
| | - Phung Chee‐Chean
- Institute for Tropical Biology and ConservationUniversiti Malaysia SabahJalan UMSKota KinabaluSabah88400Malaysia
| | - Dries Bonte
- Terrestrial Ecology UnitGhent UniversityK.L. Ledeganckstraat 35Ghent9000Belgium
| | - Elza J. Duijm
- Naturalis Biodiversity CenterDarwinweg 2Leiden2333CRThe Netherlands
| | - Joana Falcão Salles
- Groningen Institute for Evolutionary Life SciencesUniversity of GroningenP.O. Box 11103Groningen9700 CCThe Netherlands
| | - Alex L. Pigot
- Groningen Institute for Evolutionary Life SciencesUniversity of GroningenP.O. Box 11103Groningen9700 CCThe Netherlands
- Department of Genetics, Evolution and EnvironmentCentre for Biodiversity and Environment ResearchUniversity College LondonBloomsburyLondonWC1H 0AGUK
| | - Francisco J. Richter Mendoza
- Groningen Institute for Evolutionary Life SciencesUniversity of GroningenP.O. Box 11103Groningen9700 CCThe Netherlands
| | - Menno Schilthuizen
- Naturalis Biodiversity CenterDarwinweg 2Leiden2333CRThe Netherlands
- Institute for Tropical Biology and ConservationUniversiti Malaysia SabahJalan UMSKota KinabaluSabah88400Malaysia
- Institute for Biology LeidenLeiden UniversitySylviusweg 72Leiden2333 BEThe Netherlands
| | - Marti J. Anderson
- New Zealand Institute for Advanced Study (NZIAS)Massey UniversityAlbany Campus, Private Bag 102904, eCentre AL 266Auckland0745New Zealand
| | | | - Rampal S. Etienne
- Groningen Institute for Evolutionary Life SciencesUniversity of GroningenP.O. Box 11103Groningen9700 CCThe Netherlands
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Xie W, Li M, Song L, Hu X, Yang X. Biocompatibility of Alexandrium minutum in the growth and paralytic shellfish toxins production under five cultivation methods. Toxicon 2020; 182:59-65. [DOI: 10.1016/j.toxicon.2020.05.005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2019] [Revised: 04/26/2020] [Accepted: 05/15/2020] [Indexed: 12/31/2022]
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7
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Akbar MA, Mohd Yusof NY, Tahir NI, Ahmad A, Usup G, Sahrani FK, Bunawan H. Biosynthesis of Saxitoxin in Marine Dinoflagellates: An Omics Perspective. Mar Drugs 2020; 18:md18020103. [PMID: 32033403 PMCID: PMC7073992 DOI: 10.3390/md18020103] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Revised: 01/09/2020] [Accepted: 01/09/2020] [Indexed: 02/07/2023] Open
Abstract
Saxitoxin is an alkaloid neurotoxin originally isolated from the clam Saxidomus giganteus in 1957. This group of neurotoxins is produced by several species of freshwater cyanobacteria and marine dinoflagellates. The saxitoxin biosynthesis pathway was described for the first time in the 1980s and, since then, it was studied in more than seven cyanobacterial genera, comprising 26 genes that form a cluster ranging from 25.7 kb to 35 kb in sequence length. Due to the complexity of the genomic landscape, saxitoxin biosynthesis in dinoflagellates remains unknown. In order to reveal and understand the dynamics of the activity in such impressive unicellular organisms with a complex genome, a strategy that can carefully engage them in a systems view is necessary. Advances in omics technology (the collective tools of biological sciences) facilitated high-throughput studies of the genome, transcriptome, proteome, and metabolome of dinoflagellates. The omics approach was utilized to address saxitoxin-producing dinoflagellates in response to environmental stresses to improve understanding of dinoflagellates gene–environment interactions. Therefore, in this review, the progress in understanding dinoflagellate saxitoxin biosynthesis using an omics approach is emphasized. Further potential applications of metabolomics and genomics to unravel novel insights into saxitoxin biosynthesis in dinoflagellates are also reviewed.
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Affiliation(s)
- Muhamad Afiq Akbar
- School of Bioscience and Biotechnology, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi 43600, Malaysia;
| | - Nurul Yuziana Mohd Yusof
- Department of Earth Science and Environment, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi 43600, Malaysia; (N.Y.M.Y.); (F.K.S.)
| | - Noor Idayu Tahir
- Malaysian Palm Oil Board, No 6, Persiaran Institusi, Bandar Baru Bangi, Kajang 43000, Selangor, Malaysia;
| | - Asmat Ahmad
- University College Sabah Foundation, Jalan Sanzac, Kota Kinabalu 88100, Sabah, Malaysia; (A.A.); (G.U.)
| | - Gires Usup
- University College Sabah Foundation, Jalan Sanzac, Kota Kinabalu 88100, Sabah, Malaysia; (A.A.); (G.U.)
| | - Fathul Karim Sahrani
- Department of Earth Science and Environment, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, Bangi 43600, Malaysia; (N.Y.M.Y.); (F.K.S.)
| | - Hamidun Bunawan
- Institute of Systems Biology, Universiti Kebangsaan Malaysia, Bangi 43600, Malaysia
- Correspondence: ; Tel.: +60-389-214-546
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Jackrel SL, Schmidt KC, Cardinale BJ, Denef VJ. Microbiomes Reduce Their Host's Sensitivity to Interspecific Interactions. mBio 2020; 11:e02657-19. [PMID: 31964727 PMCID: PMC6974562 DOI: 10.1128/mbio.02657-19] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2019] [Accepted: 12/10/2019] [Indexed: 01/01/2023] Open
Abstract
Bacteria associated with eukaryotic hosts can affect host fitness and trophic interactions between eukaryotes, but the extent to which bacteria influence the eukaryotic species interactions within trophic levels that modulate biodiversity and species coexistence is mostly unknown. Here, we used phytoplankton, which are a classic model for evaluating interactions between species, grown with and without associated bacteria to test whether the bacteria alter the strength and type of species interactions within a trophic level. We demonstrate that host-associated bacteria alter host growth rates and carrying capacity. This did not change the type but frequently changed the strength of host interspecific interactions by facilitating host growth in the presence of an established species. These findings indicate that microbiomes can regulate their host species' interspecific interactions. As between-species interaction strength impacts their ability to coexist, our findings show that microbiomes have the potential to modulate eukaryotic species diversity and community composition.IMPORTANCE Description of the Earth's microbiota has recently undergone a phenomenal expansion that has challenged basic assumptions in many areas of biology, including hominid evolution, human gastrointestinal and neurodevelopmental disorders, and plant adaptation to climate change. By using the classic model system of freshwater phytoplankton that has been drawn upon for numerous foundational theories in ecology, we show that microbiomes, by facilitating their host population, can also influence between-species interactions among their eukaryotic hosts. Between-species interactions, including competition for resources, has been a central tenet in the field of ecology because of its implications for the diversity and composition of communities and how this in turn shapes ecosystem functioning.
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Affiliation(s)
- Sara L Jackrel
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Kathryn C Schmidt
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, USA
| | - Bradley J Cardinale
- School for Environment and Sustainability, University of Michigan, Ann Arbor, Michigan, USA
- Cooperative Institute for Great Lakes Research, University of Michigan, Ann Arbor, Michigan, USA
| | - Vincent J Denef
- Department of Ecology and Evolutionary Biology, University of Michigan, Ann Arbor, Michigan, USA
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Rambo IM, Dombrowski N, Constant L, Erdner D, Baker BJ. Metabolic relationships of uncultured bacteria associated with the microalgae Gambierdiscus. Environ Microbiol 2019; 22:1764-1783. [PMID: 31775181 DOI: 10.1111/1462-2920.14878] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2019] [Revised: 11/13/2019] [Accepted: 11/25/2019] [Indexed: 12/14/2022]
Abstract
Microbial communities inhabit algae cell surfaces and produce a variety of compounds that can impact the fitness of the host. These interactions have been studied via culturing, single-gene diversity and metagenomic read survey methods that are limited by culturing biases and fragmented genetic characterizations. Higher-resolution frameworks are needed to resolve the physiological interactions within these algal-bacterial communities. Here, we infer the encoded metabolic capabilities of four uncultured bacterial genomes (reconstructed using metagenomic assembly and binning) associated with the marine dinoflagellates Gambierdiscus carolinianus and G. caribaeus. Phylogenetic analyses revealed that two of the genomes belong to the commonly algae-associated families Rhodobacteraceae and Flavobacteriaceae. The other two genomes belong to the Phycisphaeraceae and include the first algae-associated representative within the uncultured SM1A02 group. Analyses of all four genomes suggest these bacteria are facultative aerobes, with some capable of metabolizing phytoplanktonic organosulfur compounds including dimethylsulfoniopropionate and sulfated polysaccharides. These communities may biosynthesize compounds beneficial to both the algal host and other bacteria, including iron chelators, B vitamins, methionine, lycopene, squalene and polyketides. These findings have implications for marine carbon and nutrient cycling and provide a greater depth of understanding regarding the genetic potential for complex physiological interactions between microalgae and their associated bacteria.
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Affiliation(s)
- Ian M Rambo
- Department of Marine Science, University of Texas at Austin, 750 Channel View Drive, Port Aransas, TX, 78373, USA
| | - Nina Dombrowski
- Department of Marine Science, University of Texas at Austin, 750 Channel View Drive, Port Aransas, TX, 78373, USA.,NIOZ, Royal Netherlands Institute for Sea Research, Department of Marine Microbiology and Biogeochemistry, Utrecht University, Den Burg, The Netherlands
| | - Lauren Constant
- Department of Marine Science, University of Texas at Austin, 750 Channel View Drive, Port Aransas, TX, 78373, USA
| | - Deana Erdner
- Department of Marine Science, University of Texas at Austin, 750 Channel View Drive, Port Aransas, TX, 78373, USA
| | - Brett J Baker
- Department of Marine Science, University of Texas at Austin, 750 Channel View Drive, Port Aransas, TX, 78373, USA
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