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Syukur S, Richmond J, Majzoub ME, Nappi J, Egan S, Thomas T. Not all parents are the same: Diverse strategies of symbiont transmission in seaweeds. Environ Microbiol 2024; 26:e16564. [PMID: 38151764 DOI: 10.1111/1462-2920.16564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Accepted: 12/11/2023] [Indexed: 12/29/2023]
Abstract
Different marine seaweed species have been shown to harbour specific bacterial communities, however, the extent to which vertical symbiont transmission from parents to offspring contributes to host-specificity is unclear. Here we use fluorescence and electron microscopy as well as 16S rRNA gene-based community analysis to investigate symbiont transmission in members of the three major seaweed groups (green Chlorophyta, red Rhodophyta and brown Phaeophyceae). We found seaweeds employ diverse strategies to transfer symbionts to their progeny. For instance, the green Ulva australis does not appear to have the capacity for vertical transmission. In contrast, the brown Phyllospora comosa adopts a non-selective vertical transmission. The red Delisea pulchra demonstrates weak selectivity in symbiont transmission, while the brown Hormosira banksii exhibits a strongly selective symbiont transfer. Mucilage on the gametes appears to facilitate vertical transmission and transferred bacteria have predicted properties that could support early development of the seaweeds. Previous meta-analysis has indicated that vertical transmission is rare in aquatic compared to terrestrial environments, however, our results contribute to the growing evidence that this might not be the case and that instead vertical transmission with various degrees of symbiont selection occurs in the ecologically important group of seaweeds.
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Affiliation(s)
- Syukur Syukur
- Centre for Marine Science and Innovation, School of Biological, Earth and Environmental Sciences, UNSW Sydney, Kensington, Australia
| | - Joanna Richmond
- Electron Microscope Unit, Mark Wainwright Analytical Centre, UNSW Sydney, Kensington, Australia
| | - Marwan E Majzoub
- Centre for Marine Science and Innovation, School of Biological, Earth and Environmental Sciences, UNSW Sydney, Kensington, Australia
| | - Jadranka Nappi
- Centre for Marine Science and Innovation, School of Biological, Earth and Environmental Sciences, UNSW Sydney, Kensington, Australia
| | - Suhelen Egan
- Centre for Marine Science and Innovation, School of Biological, Earth and Environmental Sciences, UNSW Sydney, Kensington, Australia
| | - Torsten Thomas
- Centre for Marine Science and Innovation, School of Biological, Earth and Environmental Sciences, UNSW Sydney, Kensington, Australia
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2
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Setia G, Chen J, Schlub R, Husseneder C. Taxonomic profiling of Nasutitermes takasagoensis microbiota to investigate the role of termites as vectors of bacteria linked to ironwood tree decline in Guam. PLoS One 2023; 18:e0296081. [PMID: 38134025 PMCID: PMC10745211 DOI: 10.1371/journal.pone.0296081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2023] [Accepted: 12/06/2023] [Indexed: 12/24/2023] Open
Abstract
The ironwood tree (Casuarina equisetifolia, family Casuarinaceae), an indigenous agroforestry species in Guam, has been threatened by ironwood tree decline (IWTD) since 2002. Formation of bacterial ooze by the wilt pathogen from the Ralstonia solanacearum species complex and wetwood bacteria (primarily Klebsiella species) has been linked to IWTD. In addition, termite infestation of trees was statistically associated with IWTD. Termites are known carriers of a diverse microbiome. Therefore, we hypothesized that termites could be vectors of bacteria linked to IWTD. To investigate the potential role of termites as pathogen vectors, we employed next-generation 16S rRNA gene sequencing to describe the bacteria diversity of Nasutitermes takasagoensis (Family Termitidae) workers collected from 42 ironwood trees of different disease stages in Guam in association with tree-, plot-, and location-related factors. Nasutitermes takasagoensis workers account for the majority of termite infestations of ironwood trees. The bacterial phyla composition of N. takasagoensis workers was typical for wood-feeding higher termites consisting mainly of Spirochaetes and Fibrobacteres. However, Ralstonia species were not detected and Klebsiella species were rare even in termites collected from trees infected with Ralstonia and wetwood bacteria. Feeding experiments suggested that termites prefer to consume wood with low pathogen content over wood with high pathogen load. Termites were able to ingest Ralstonia but Ralstonia could not establish itself in healthy termite bodies. We concluded that N. takasagoensis workers are not vectors for Ralstonia spp. or the bacterial endophytes associated with wetwood (Klebsiella, Pantoea, Enterobacter, Citrobacter, and Erwinia) that were previously observed in IWTD-infested trees. The bacterial diversity in termite samples was significantly influenced by various factors, including Tree Health, Site Management, Plot Average Decline Severity, Proportion of Dead Trees in the Plot, Proportion of Trees with Termite Damage in the Plot, Presence of Ralstonia, and Altitude.
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Affiliation(s)
- Garima Setia
- Department of Entomology, Louisiana State University Agricultural Center, Baton Rouge, LA, United States of America
| | - Junyan Chen
- Department of Entomology, Louisiana State University Agricultural Center, Baton Rouge, LA, United States of America
| | - Robert Schlub
- University of Guam, Cooperative Extension Service, Mangilao, Guam
| | - Claudia Husseneder
- Department of Entomology, Louisiana State University Agricultural Center, Baton Rouge, LA, United States of America
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3
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Karimi E, Dittami SM. Maintaining beneficial alga-associated bacterial communities under heat stress: insights from controlled co-culture experiments using antibiotic-resistant bacterial strains. FEMS Microbiol Ecol 2023; 99:fiad130. [PMID: 37833238 DOI: 10.1093/femsec/fiad130] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2023] [Revised: 09/29/2023] [Accepted: 10/12/2023] [Indexed: 10/15/2023] Open
Abstract
Brown algae, like many eukaryotes, possess diverse microbial communities. Ectocarpus-a model brown alga-relies on these communities for essential processes, such as growth development. Controlled laboratory systems are needed for functional studies of these algal-bacterial interactions. We selected bacterial strains based on their metabolic networks to provide optimal completion of the algal metabolism, rendered them resistant to two antibiotics, and inoculate them to establish controlled co-cultures with Ectocarpus under continuous antibiotic treatment. We then monitored the stability of the resulting associations under control conditions and heat stress using 16S metabarcoding. Antibiotics strongly reduced bacterial diversity both in terms of taxonomy and predicted metabolic functions. In the inoculated sample, 63%-69% of reads corresponded to the inoculated strains, and the communities remained stable during temperature stress. They also partially restored the predicted metabolic functions of the natural community. Overall, the development of antibiotic-resistant helper cultures offers a promising route to fully controlled laboratory experiments with algae and microbiota and thus represents an important step towards generating experimental evidence for specific host-microbe interactions in the systems studied. Further work will be required to achieve full control and progressively expand our repertoire of helper strains including those currently 'unculturable'.
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Affiliation(s)
- Elham Karimi
- Integrative Biology of Marine Models, Sorbonne Université/CNRS, UMR8227, Station Biologique de Roscoff, CS 90074, 29688 Roscoff Cedex, France
| | - Simon M Dittami
- Integrative Biology of Marine Models, Sorbonne Université/CNRS, UMR8227, Station Biologique de Roscoff, CS 90074, 29688 Roscoff Cedex, France
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Wang Q, Ye W, Tao Y, Li Y, Lu S, Xu P, Qiang J. Transport Stress Induces Oxidative Stress and Immune Response in Juvenile Largemouth Bass ( Micropterus salmoides): Analysis of Oxidative and Immunological Parameters and the Gut Microbiome. Antioxidants (Basel) 2023; 12:antiox12010157. [PMID: 36671019 PMCID: PMC9854791 DOI: 10.3390/antiox12010157] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2022] [Revised: 01/05/2023] [Accepted: 01/06/2023] [Indexed: 01/11/2023] Open
Abstract
Transport is essential in cross-regional culturing of juvenile fish. Largemouth bass (Micropterus salmoides) often exhibit decreased vitality and are susceptible to disease after transportation. To study the effects of transport stress on juvenile largemouth bass, juveniles (average length: 8.42 ± 0.44 cm, average weight 10.26 ± 0.32 g) were subjected to a 12 h simulated transport, then subsequently, allowed to recover for 5 d. Liver and intestinal tissues were collected at 0, 6 and 12 h after transport stress and after 5 d of recovery. Oxidative and immunological parameters and the gut microbiome were analyzed. Hepatocytic vacuolization and shortened intestinal villi in the bass indicated liver and intestinal damage due to transport stress. Superoxide dismutase, lysozyme and complement C3 activities were significantly increased during transport stress (p < 0.05), indicating that transport stress resulted in oxidative stress and altered innate immune responses in the bass. With the transport stress, the malondialdehyde content first increased, then significantly decreased (p < 0.05) and showed an increasing trend in the recovery group. 16S rDNA analysis revealed that transport stress strongly affected the gut microbial compositions, mainly among Proteobacteria, Firmicutes, Cyanobacteria and Spirochaetes. The Proteobacteria abundance increased significantly after transport. The Kyoto Encyclopedia of Genes and Genomes functional analysis revealed that most gut microbes played roles in membrane transport, cell replication and repair. Correlation analyses demonstrated that the dominant genera varied significantly and participated in the measured physiological parameter changes. With 5 days of recovery after 12 h of transport stress, the physiological parameters and gut microbiome differed significantly between the experimental and control groups. These results provide a reference and basis for studying transport-stress-induced oxidative and immune mechanisms in juvenile largemouth bass to help optimize juvenile largemouth bass transportation.
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Affiliation(s)
- Qingchun Wang
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081, China
| | - Wei Ye
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China
| | - Yifan Tao
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China
| | - Yan Li
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China
- Correspondence: (Y.L.); (J.Q.)
| | - Siqi Lu
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China
| | - Pao Xu
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081, China
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China
| | - Jun Qiang
- Wuxi Fisheries College, Nanjing Agricultural University, Wuxi 214081, China
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi 214081, China
- Correspondence: (Y.L.); (J.Q.)
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Burgunter-Delamare B, Rousvoal S, Legeay E, Tanguy G, Fredriksen S, Boyen C, Dittami SM. The Saccharina latissima microbiome: Effects of region, season, and physiology. Front Microbiol 2023; 13:1050939. [PMID: 36687663 PMCID: PMC9858215 DOI: 10.3389/fmicb.2022.1050939] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2022] [Accepted: 12/12/2022] [Indexed: 01/09/2023] Open
Abstract
Introduction Saccharina latissima is a canopy-forming species of brown algae and, as such, is considered an ecosystem engineer. Several populations of this alga are exploited worldwide, and a decrease in the abundance of S. latissima at its southern distributional range limits has been observed. Despite its economic and ecological interest, only a few data are available on the composition of microbiota associated with S. latissima and its role in algal physiologyn. Methods We studied the whole bacterial community composition associated with S. latissima samples from three locations (Brittany, Helgoland, and Skagerrak) by 16S metabarcoding analyses at different scales: algal blade part, regions, season (at one site), and algal physiologic state. Results and Discussion We have shown that the difference in bacterial composition is driven by factors of decreasing importance: (i) the algal tissues (apex/meristem), (ii) the geographical area, (iii) the seasons (at the Roscoff site), and (iv) the algal host's condition (healthy vs. symptoms). Overall, Alphaproteobacteria, Gammaproteobacteria, and Bacteroidia dominated the general bacterial communities. Almost all individuals hosted bacteria of the genus Granulosicoccus, accounting for 12% of the total sequences, and eight additional core genera were identified. Our results also highlight a microbial signature characteristic for algae in poor health independent of the disease symptoms. Thus, our study provides a comprehensive overview of the S. latissima microbiome, forming a basis for understanding holobiont functioning.
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Affiliation(s)
- Bertille Burgunter-Delamare
- CNRS, Sorbonne Université, Integrative Biology of Marine Models (LBI2M), Station Biologique de Roscoff, Roscoff, France,*Correspondence: Bertille Burgunter-Delamare,
| | - Sylvie Rousvoal
- CNRS, Sorbonne Université, Integrative Biology of Marine Models (LBI2M), Station Biologique de Roscoff, Roscoff, France
| | - Erwan Legeay
- FR2424 Station Biologique de Roscoff, CNRS, Sorbonne Université, Roscoff, France
| | - Gwenn Tanguy
- FR2424 Station Biologique de Roscoff, CNRS, Sorbonne Université, Roscoff, France
| | | | - Catherine Boyen
- CNRS, Sorbonne Université, Integrative Biology of Marine Models (LBI2M), Station Biologique de Roscoff, Roscoff, France,FR2424 Station Biologique de Roscoff, CNRS, Sorbonne Université, Roscoff, France
| | - Simon M. Dittami
- CNRS, Sorbonne Université, Integrative Biology of Marine Models (LBI2M), Station Biologique de Roscoff, Roscoff, France,Simon M. Dittami,
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Lobanov V, Gobet A, Joyce A. Ecosystem-specific microbiota and microbiome databases in the era of big data. ENVIRONMENTAL MICROBIOME 2022; 17:37. [PMID: 35842686 PMCID: PMC9287977 DOI: 10.1186/s40793-022-00433-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2022] [Accepted: 06/29/2022] [Indexed: 05/05/2023]
Abstract
The rapid development of sequencing methods over the past decades has accelerated both the potential scope and depth of microbiota and microbiome studies. Recent developments in the field have been marked by an expansion away from purely categorical studies towards a greater investigation of community functionality. As in-depth genomic and environmental coverage is often distributed unequally across major taxa and ecosystems, it can be difficult to identify or substantiate relationships within microbial communities. Generic databases containing datasets from diverse ecosystems have opened a new era of data accessibility despite costs in terms of data quality and heterogeneity. This challenge is readily embodied in the integration of meta-omics data alongside habitat-specific standards which help contextualise datasets both in terms of sample processing and background within the ecosystem. A special case of large genomic repositories, ecosystem-specific databases (ES-DB's), have emerged to consolidate and better standardise sample processing and analysis protocols around individual ecosystems under study, allowing independent studies to produce comparable datasets. Here, we provide a comprehensive review of this emerging tool for microbial community analysis in relation to current trends in the field. We focus on the factors leading to the formation of ES-DB's, their comparison to traditional microbial databases, the potential for ES-DB integration with meta-omics platforms, as well as inherent limitations in the applicability of ES-DB's.
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Affiliation(s)
- Victor Lobanov
- Department of Marine Sciences, University of Gothenburg, Box 461, 405 30, Gothenburg, Sweden
| | | | - Alyssa Joyce
- Department of Marine Sciences, University of Gothenburg, Box 461, 405 30, Gothenburg, Sweden.
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7
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Burgunter-Delamare B, Tanguy G, Legeay E, Boyen C, Dittami SM. Effects of sampling and storage procedures on 16S rDNA amplicon sequencing results of kelp microbiomes. Mar Genomics 2022; 63:100944. [PMID: 35299055 DOI: 10.1016/j.margen.2022.100944] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2021] [Revised: 02/24/2022] [Accepted: 02/24/2022] [Indexed: 10/18/2022]
Abstract
Brown macroalgae, including the kelp Saccharina latissima, are of both ecological and increasing economic interest. Together with their microbiota, these organisms form a singular entity, the holobiont. Sampling campaigns are required to study the microbiome of algae in natural populations, but freezing samples in liquid nitrogen is complex in the field, particularly at remote locations. Here we tested two simple alternative methods for sampling the microbial diversity associated with the kelp S. latissima: silica gel conservation of tissue and swab samples preserved in DNA/RNA shield solution. We used these techniques to compare apex and meristem samples from Roscoff (Brittany, France) and evaluated their impact on the results of 16S rDNA metabarcoding experiments. Both methods were able to separate apex and meristem microbiomes, and the results were concordant with results obtained for flash-frozen samples. However, differences were observed for several rare genera and ASVs, and the detection of contaminant sequences in the silica gel-preserved samples underline the importance of including blank samples for this method. Globally, our results confirm that the silica gel technique and swabbing combined with DNA/RNA shield preservation are valid alternatives to liquid nitrogen preservation when sampling brown macroalgae in the field. However, they also underline that, regardless of the method, caution should be taken when interpreting data on rare sequences.
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Affiliation(s)
- Bertille Burgunter-Delamare
- CNRS, Sorbonne Université, Integrative Biology of Marine Models (LBI2M), Station Biologique de Roscoff, 29680 Roscoff, France.
| | - Gwenn Tanguy
- CNRS, Sorbonne Université, FR2424 Station Biologique de Roscoff, 29680 Roscoff, France
| | - Erwan Legeay
- CNRS, Sorbonne Université, FR2424 Station Biologique de Roscoff, 29680 Roscoff, France
| | - Catherine Boyen
- CNRS, Sorbonne Université, Integrative Biology of Marine Models (LBI2M), Station Biologique de Roscoff, 29680 Roscoff, France; CNRS, Sorbonne Université, FR2424 Station Biologique de Roscoff, 29680 Roscoff, France
| | - Simon M Dittami
- CNRS, Sorbonne Université, Integrative Biology of Marine Models (LBI2M), Station Biologique de Roscoff, 29680 Roscoff, France.
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van der Loos LM, D'hondt S, Willems A, De Clerck O. Characterizing algal microbiomes using long-read nanopore sequencing. ALGAL RES 2021. [DOI: 10.1016/j.algal.2021.102456] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
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9
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Paix B, Potin P, Schires G, Le Poupon C, Misson B, Leblanc C, Culioli G, Briand JF. Synergistic effects of temperature and light affect the relationship between Taonia atomaria and its epibacterial community: a controlled conditions study. Environ Microbiol 2021; 23:6777-6797. [PMID: 34490980 DOI: 10.1111/1462-2920.15758] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Revised: 09/03/2021] [Accepted: 09/03/2021] [Indexed: 11/29/2022]
Abstract
In the context of global warming, this study aimed to assess the effect of temperature and irradiance on the macroalgal Taonia atomaria holobiont dynamics. We developed an experimental set-up using aquaria supplied by natural seawater with three temperatures combined with three irradiances. The holobiont response was monitored over 14 days using a multi-omics approach coupling algal surface metabolomics and metabarcoding. Both temperature and irradiance appeared to shape the microbiota and the surface metabolome, but with a distinct temporality. Epibacterial community first changed according to temperature, and later in relation to irradiance, while the opposite occurred for the surface metabolome. An increased temperature revealed a decreasing richness of the epiphytic community together with an increase of several bacterial taxa. Irradiance changes appeared to quickly impact surface metabolites production linked with the algal host photosynthesis (e.g. mannitol, fucoxanthin, dimethylsulfoniopropionate), which was hypothesized to explain modifications of the structure of the epiphytic community. Algal host may also directly adapt its surface metabolome to changing temperature with time (e.g. lipids content) and also in response to changing microbiota (e.g. chemical defences). Finally, this study brought new insights highlighting complex direct and indirect responses of seaweeds and their associated microbiota under changing environments.
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Affiliation(s)
- Benoit Paix
- Université de Toulon, Laboratoire MAPIEM, La Garde, EA 4323, France
| | - Philippe Potin
- Sorbonne Université, CNRS, Integrative Biology of Marine Models (LBI2M), UMR 8227, Station Biologique de Roscoff (SBR), Roscoff, France
| | - Gaëtan Schires
- Sorbonne Université, CNRS, Center for Biological Marine Resources (CRBM), FR 2424, Station Biologique de Roscoff (SBR), Roscoff, France
| | - Christophe Le Poupon
- Université de Toulon, Aix Marseille Université, CNRS, IRD, Mediterranean Institute of Oceanography (MIO), UM110, La Garde, France
| | - Benjamin Misson
- Université de Toulon, Aix Marseille Université, CNRS, IRD, Mediterranean Institute of Oceanography (MIO), UM110, La Garde, France
| | - Catherine Leblanc
- Sorbonne Université, CNRS, Integrative Biology of Marine Models (LBI2M), UMR 8227, Station Biologique de Roscoff (SBR), Roscoff, France
| | - Gérald Culioli
- Université de Toulon, Laboratoire MAPIEM, La Garde, EA 4323, France
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Thomas F, Le Duff N, Wu TD, Cébron A, Uroz S, Riera P, Leroux C, Tanguy G, Legeay E, Guerquin-Kern JL. Isotopic tracing reveals single-cell assimilation of a macroalgal polysaccharide by a few marine Flavobacteria and Gammaproteobacteria. THE ISME JOURNAL 2021; 15:3062-3075. [PMID: 33953365 PMCID: PMC8443679 DOI: 10.1038/s41396-021-00987-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Revised: 03/25/2021] [Accepted: 04/09/2021] [Indexed: 02/03/2023]
Abstract
Algal polysaccharides constitute a diverse and abundant reservoir of organic matter for marine heterotrophic bacteria, central to the oceanic carbon cycle. We investigated the uptake of alginate, a major brown macroalgal polysaccharide, by microbial communities from kelp-dominated coastal habitats. Congruent with cell growth and rapid substrate utilization, alginate amendments induced a decrease in bacterial diversity and a marked compositional shift towards copiotrophic bacteria. We traced 13C derived from alginate into specific bacterial incorporators and quantified the uptake activity at the single-cell level, using halogen in situ hybridization coupled to nanoscale secondary ion mass spectrometry (HISH-SIMS) and DNA stable isotope probing (DNA-SIP). Cell-specific alginate uptake was observed for Gammaproteobacteria and Flavobacteriales, with carbon assimilation rates ranging from 0.14 to 27.50 fg C µm-3 h-1. DNA-SIP revealed that only a few initially rare Flavobacteriaceae and Alteromonadales taxa incorporated 13C from alginate into their biomass, accounting for most of the carbon assimilation based on bulk isotopic measurements. Functional screening of metagenomic libraries gave insights into the genes of alginolytic Alteromonadales active in situ. These results highlight the high degree of niche specialization in heterotrophic communities and help constraining the quantitative role of polysaccharide-degrading bacteria in coastal ecosystems.
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Affiliation(s)
- François Thomas
- Sorbonne Université, CNRS, Integrative Biology of Marine Models (LBI2M), Station Biologique de Roscoff (SBR), Roscoff, France.
| | - Nolwen Le Duff
- Sorbonne Université, CNRS, Integrative Biology of Marine Models (LBI2M), Station Biologique de Roscoff (SBR), Roscoff, France
| | - Ting-Di Wu
- Institut Curie, Université Paris-Saclay, Paris, France
- Université Paris-Saclay, INSERM US43, CNRS UMS2016, Multimodal Imaging Center, Orsay, France
| | | | - Stéphane Uroz
- Université de Lorraine, INRAE, UMR1136 « Interactions Arbres-Microorganismes », Champenoux, France
| | - Pascal Riera
- Sorbonne Université, CNRS, UMR7144, Station Biologique de Roscoff (SBR), Roscoff, France
| | - Cédric Leroux
- CNRS, Sorbonne Université, FR2424, Metabomer, Station Biologique de Roscoff, Roscoff, France
| | - Gwenn Tanguy
- CNRS, Sorbonne Université, FR2424, Genomer, Station Biologique de Roscoff, Roscoff, France
| | - Erwan Legeay
- CNRS, Sorbonne Université, FR2424, Genomer, Station Biologique de Roscoff, Roscoff, France
| | - Jean-Luc Guerquin-Kern
- Institut Curie, Université Paris-Saclay, Paris, France
- Université Paris-Saclay, INSERM US43, CNRS UMS2016, Multimodal Imaging Center, Orsay, France
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11
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Brunet M, de Bettignies F, Le Duff N, Tanguy G, Davoult D, Leblanc C, Gobet A, Thomas F. Accumulation of detached kelp biomass in a subtidal temperate coastal ecosystem induces succession of epiphytic and sediment bacterial communities. Environ Microbiol 2021; 23:1638-1655. [PMID: 33400326 PMCID: PMC8248336 DOI: 10.1111/1462-2920.15389] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2020] [Revised: 12/14/2020] [Accepted: 01/02/2021] [Indexed: 12/30/2022]
Abstract
Kelps are dominant primary producers in temperate coastal ecosystems. Large amounts of kelp biomass can be exported to the seafloor during the algal growth cycle or following storms, creating new ecological niches for the associated microbiota. Here, we investigated the bacterial community associated with the kelp Laminaria hyperborea during its accumulation and degradation on the seafloor. Kelp tissue, seawater and sediment were sampled during a 6-month in situ experiment simulating kelp detritus accumulation. Evaluation of the epiphytic bacterial community abundance, structure, taxonomic composition and predicted functional profiles evidenced a biphasic succession. Initially, dominant genera (Hellea, Litorimonas, Granulosicoccus) showed a rapid and drastic decrease in sequence abundance, probably outcompeted by algal polysaccharide-degraders such as Bacteroidia members which responded within 4 weeks. Acidimicrobiia, especially members of the Sva0996 marine group, colonized the degrading kelp biomass after 11 weeks. These secondary colonizers could act as opportunistic scavenger bacteria assimilating substrates exposed by early degraders. In parallel, kelp accumulation modified bacterial communities in the underlying sediment, notably favouring anaerobic taxa potentially involved in the sulfur and nitrogen cycles. Overall, this study provides insights into the bacterial degradation of algal biomass in situ, an important link in coastal trophic chains.
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Affiliation(s)
- Maéva Brunet
- Sorbonne Université, CNRS, Integrative Biology of Marine Models (LBI2M), Station Biologique de Roscoff (SBR)Roscoff29680France
| | - Florian de Bettignies
- Sorbonne Université, CNRS, UMR 7144 AD2M, Station Biologique de Roscoff (SBR)Roscoff29680France
| | - Nolwen Le Duff
- Sorbonne Université, CNRS, Integrative Biology of Marine Models (LBI2M), Station Biologique de Roscoff (SBR)Roscoff29680France
| | - Gwenn Tanguy
- Sorbonne Université, CNRS, FR2424, Genomer, Station Biologique de RoscoffRoscoff29680France
| | - Dominique Davoult
- Sorbonne Université, CNRS, UMR 7144 AD2M, Station Biologique de Roscoff (SBR)Roscoff29680France
| | - Catherine Leblanc
- Sorbonne Université, CNRS, Integrative Biology of Marine Models (LBI2M), Station Biologique de Roscoff (SBR)Roscoff29680France
| | - Angélique Gobet
- Sorbonne Université, CNRS, Integrative Biology of Marine Models (LBI2M), Station Biologique de Roscoff (SBR)Roscoff29680France
- MARBEC, Univ Montpellier, CNRS, Ifremer, IRDSèteFrance
| | - François Thomas
- Sorbonne Université, CNRS, Integrative Biology of Marine Models (LBI2M), Station Biologique de Roscoff (SBR)Roscoff29680France
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Dittami SM, Peters AF, West JA, Cariou T, KleinJan H, Burgunter-Delamare B, Prechoux A, Egan S, Boyen C. Revisiting Australian Ectocarpus subulatus (Phaeophyceae) From the Hopkins River: Distribution, Abiotic Environment, and Associated Microbiota. JOURNAL OF PHYCOLOGY 2020; 56:719-729. [PMID: 31965565 DOI: 10.1111/jpy.12970] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Accepted: 01/07/2020] [Indexed: 05/24/2023]
Abstract
In 1995 a strain of Ectocarpus was isolated from Hopkins River Falls, Victoria, Australia, constituting one of few available freshwater or nearly freshwater brown algae, and the only one belonging to the genus Ectocarpus. It has since been used as a model to study acclimation and adaptation to low salinities and the role of its microbiota in these processes. To provide more background information on this model, we assessed if Ectocarpus was still present in the Hopkins river 22 years after the original finding, estimated its present distribution, described its abiotic environment, and determined its in situ microbial composition. We sampled for Ectocarpus at 15 sites along the Hopkins River as well as 10 neighboring sites and found individuals with ITS and cox1 sequences identical to the original isolate at three sites upstream of Hopkins River Falls. The salinity of the water at these sites ranged from 3.1 to 6.9, and it was rich in sulfate (1-5 mM). The diversity of bacteria associated with the algae in situ (1312 operational taxonomic units) was one order of magnitude higher than in previous studies of the original laboratory culture, and 95 alga-associated bacterial strains were isolated from algal filaments on site. In particular, species of Planctomycetes were abundant in situ but rare in laboratory cultures. Our results confirmed that Ectocarpus was still present in the Hopkins River, and the newly isolated algal and bacterial strains offer new possibilities to study the adaptation of Ectocarpus to low salinity and its interactions with its microbiome.
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Affiliation(s)
- Simon M Dittami
- CNRS, Integrative Biology of Marine Models (LBI2M), Station Biologique de Roscoff, Sorbonne Université, 29680, Roscoff, France
| | - Akira F Peters
- Bezhin Rosko, 40 Rue des Pêcheurs, 29250, Santec, France
| | - John A West
- Biosciences 2, University of Melbourne, Parkville, VIC, 3010, Australia
| | - Thierry Cariou
- CNRS, FR2424, Station Biologique de Roscoff, Sorbonne Université, 29680, Roscoff, France
| | - Hetty KleinJan
- CNRS, Integrative Biology of Marine Models (LBI2M), Station Biologique de Roscoff, Sorbonne Université, 29680, Roscoff, France
| | - Bertille Burgunter-Delamare
- CNRS, Integrative Biology of Marine Models (LBI2M), Station Biologique de Roscoff, Sorbonne Université, 29680, Roscoff, France
| | - Aurélie Prechoux
- CNRS, Integrative Biology of Marine Models (LBI2M), Station Biologique de Roscoff, Sorbonne Université, 29680, Roscoff, France
| | - Suhelen Egan
- Centre for Marine Science and Innovation, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, NSW, Australia
| | - Catherine Boyen
- CNRS, Integrative Biology of Marine Models (LBI2M), Station Biologique de Roscoff, Sorbonne Université, 29680, Roscoff, France
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