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Li X, Lippens G, Parrou JL, Cioci G, Esque J, Wang Z, Laville E, Potocki-Veronese G, Labourel A. Biochemical characterization of a SusD-like protein involved in β-1,3-glucan utilization by an uncultured cow rumen Bacteroides. mSphere 2024; 9:e0027824. [PMID: 39012103 PMCID: PMC11351036 DOI: 10.1128/msphere.00278-24] [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: 04/05/2024] [Accepted: 06/18/2024] [Indexed: 07/17/2024] Open
Abstract
In ruminants, the rumen is a specialized stomach that is adapted to the breakdown of plant-derived complex polysaccharides through the coordinated activities of a diverse microbial community. Bacteroidota is a major phylum in this bovine rumen microbiota. They contain several clusters of genes called polysaccharide utilization loci (PULs) that encode proteins working in concert to capture, degrade, and transport polysaccharides. Despite the critical role of SusD-like proteins for efficient substrate transport, they remain largely unexplored. Here, we present the biochemical characterization of a SusD-like protein encoded by a β-glucan utilization locus from an Escherichia coli metagenomic clone previously isolated by functional screening of the bovine rumen microbiome. In this study, we show that clone 41O1 can grow on laminaritriose, cellotriose, and a mixture of cellobiosyl-cellobiose and glucosyl-cellotriose as sole carbon sources. Based on this, we used various in vitro analyses to investigate the binding ability of 41O1_SusD-like towards these oligosaccharides and the corresponding polysaccharides. We observed a clear binding affinity for β-1,6 branched β-1,3-glucans (laminarins, yeast β-glucan) and laminaritriose. Comparison of the AlphaFold2 model of 41O1_SusD-like with its closest structural homologs highlights a similar pattern of substrate recognition. In particular, three tryptophan residues are shown to be crucial for laminarin recognition. In the context of the cow rumen, we discuss the possible substrates targeted by the 41O1_PUL, such as the (1,3;1,4)-β-d-glucans present in cereal grains or the β-1,3- and (1,3;1,6)-β-d-glucans that are components of the cell wall of ruminal yeasts.IMPORTANCEThe rumen microbiota can majorly impact overall animal health, feed efficiency, and release of harmful substances into the environment. This microbiota is involved in the fermentation of organic matter to provide the host with valuable and assimilable nutrients. Bacteroidota efficiently captures, breaks down, and imports complex polysaccharides through the concerted action of proteins encoded by polysaccharide utilization loci (PULs). Within this system, SusD-like protein has proven necessary for the active internalization of the substrate. Nevertheless, the vast majority of SusD-like proteins characterized to date originate from cultured bacteria. With regard to the diversity and importance of uncultured bacteria in the rumen, further studies are required to better understand the role of polysaccharide utilization loci in ruminal polysaccharide degradation. Our detailed characterization of the 41O1_SusD-like therefore contributes to a better understanding of the carbohydrate metabolism of an uncultured Bacteroides from the cow rumen.
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Affiliation(s)
- Xiaoqian Li
- TBI, Université de Toulouse, CNRS, INRAE, INSA, Toulouse, France
| | - Guy Lippens
- TBI, Université de Toulouse, CNRS, INRAE, INSA, Toulouse, France
| | - Jean-Luc Parrou
- TBI, Université de Toulouse, CNRS, INRAE, INSA, Toulouse, France
| | - Gianluca Cioci
- TBI, Université de Toulouse, CNRS, INRAE, INSA, Toulouse, France
| | - Jérémy Esque
- TBI, Université de Toulouse, CNRS, INRAE, INSA, Toulouse, France
| | - Zhi Wang
- TBI, Université de Toulouse, CNRS, INRAE, INSA, Toulouse, France
| | | | | | - Aurore Labourel
- TBI, Université de Toulouse, CNRS, INRAE, INSA, Toulouse, France
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Kalenborn S, Zühlke D, Reintjes G, Riedel K, Amann RI, Harder J. Genes for laminarin degradation are dispersed in the genomes of particle-associated Maribacter species. Front Microbiol 2024; 15:1393588. [PMID: 39188312 PMCID: PMC11345257 DOI: 10.3389/fmicb.2024.1393588] [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: 02/29/2024] [Accepted: 07/17/2024] [Indexed: 08/28/2024] Open
Abstract
Laminarin is a cytosolic storage polysaccharide of phytoplankton and macroalgae and accounts for over 10% of the world's annually fixed carbon dioxide. Algal disruption, for example, by viral lysis releases laminarin. The soluble sugar is rapidly utilized by free-living planktonic bacteria, in which sugar transporters and the degrading enzymes are frequently encoded in polysaccharide utilization loci. The annotation of flavobacterial genomes failed to identify canonical laminarin utilization loci in several particle-associated bacteria, in particular in strains of Maribacter. In this study, we report in vivo utilization of laminarin by Maribacter forsetii accompanied by additional cell growth and proliferation. Laminarin utilization coincided with the induction of an extracellular endo-laminarinase, SusC/D outer membrane oligosaccharide transporters, and a periplasmic glycosyl hydrolase family 3 protein. An ABC transport system and sugar kinases were expressed. Endo-laminarinase activity was also observed in Maribacter sp. MAR_2009_72, Maribacter sp. Hel_I_7, and Maribacter dokdonensis MAR_2009_60. Maribacter dokdonensis MAR_2009_71 lacked the large endo-laminarinase gene in the genome and had no endo-laminarinase activity. In all genomes, genes of induced proteins were scattered across the genome rather than clustered in a laminarin utilization locus. These observations revealed that the Maribacter strains investigated in this study participate in laminarin utilization, but in contrast to many free-living bacteria, there is no co-localization of genes encoding the enzymatic machinery for laminarin utilization.
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Affiliation(s)
- Saskia Kalenborn
- Department of Molecular Ecology, Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Daniela Zühlke
- Department for Microbial Physiology and Molecular Biology, University of Greifswald, Greifswald, Germany
| | - Greta Reintjes
- Microbial Carbohydrate Interaction Group, Department of Biology and Chemistry, University of Bremen, Bremen, Germany
| | - Katharina Riedel
- Department for Microbial Physiology and Molecular Biology, University of Greifswald, Greifswald, Germany
| | - Rudolf I. Amann
- Department of Molecular Ecology, Max Planck Institute for Marine Microbiology, Bremen, Germany
| | - Jens Harder
- Department of Molecular Ecology, Max Planck Institute for Marine Microbiology, Bremen, Germany
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Hameleers L, Gaenssle LA, Bertran‐Llorens S, Pijning T, Jurak E. Polysaccharide utilization loci encoded DUF1735 likely functions as membrane-bound spacer for carbohydrate active enzymes. FEBS Open Bio 2024; 14:1133-1146. [PMID: 38735878 PMCID: PMC11216935 DOI: 10.1002/2211-5463.13816] [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: 12/22/2023] [Revised: 03/17/2024] [Accepted: 04/29/2024] [Indexed: 05/14/2024] Open
Abstract
Proteins featuring the Domain of Unknown Function 1735 are frequently found in Polysaccharide Utilization Loci, yet their role remains unknown. The domain and vicinity analyzer programs we developed mine the Kyoto Encyclopedia of Genes and Genomes and UniProt to enhance the functional prediction of DUF1735. Our datasets confirmed the exclusive presence of DUF1735 in Bacteroidota genomes, with Bacteroidetes thetaiotaomicron harboring 46 copies. Notably, 97.8% of DUF1735 are encoded in PULs, and 89% are N-termini of multimodular proteins featuring C-termini like Laminin_G_3, F5/8-typeC, and GH18 domains. Predominantly possessing a predicted lipoprotein signal peptide and sharing an immunoglobulin-like β-sandwich fold with the BACON domain and the N-termini of SusE/F, DUF1735 likely functions as N-terminal, membrane-bound spacer for diverse C-termini involved in PUL-mediated carbohydrate utilization.
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Affiliation(s)
- Lisanne Hameleers
- Department of Bioproduct EngineeringUniversity of GroningenThe Netherlands
| | - Lucie A. Gaenssle
- Department of Bioproduct EngineeringUniversity of GroningenThe Netherlands
| | | | - Tjaard Pijning
- Department of Biomolecular X‐ray Crystallography, Groningen Biomolecular Sciences and Biotechnology Institute (GBB)University of GroningenThe Netherlands
| | - Edita Jurak
- Department of Bioproduct EngineeringUniversity of GroningenThe Netherlands
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Nakamura S, Kurata R, Miyazaki T. Structural insights into α-(1→6)-linkage preference of GH97 glucodextranase from Flavobacterium johnsoniae. FEBS J 2024; 291:3267-3282. [PMID: 38661728 DOI: 10.1111/febs.17139] [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: 12/20/2023] [Revised: 03/07/2024] [Accepted: 04/10/2024] [Indexed: 04/26/2024]
Abstract
Glycoside hydrolase family 97 (GH97) comprises enzymes like anomer-inverting α-glucoside hydrolases (i.e., glucoamylase) and anomer-retaining α-galactosidases. In a soil bacterium, Flavobacterium johnsoniae, we previously identified a GH97 enzyme (FjGH97A) within the branched dextran utilization locus. It functions as an α-glucoside hydrolase, targeting α-(1→6)-glucosidic linkages in dextran and isomaltooligosaccharides (i.e., glucodextranase). FjGH97A exhibits a preference for α-(1→6)-glucoside linkages over α-(1→4)-linkages, while Bacteroides thetaiotaomicron glucoamylase SusB (with 69% sequence identity), which is involved in the starch utilization system, exhibits the highest specificity for α-(1→4)-glucosidic linkages. Here, we examined the crystal structures of FjGH97A in complexes with glucose, panose, or isomaltotriose, and analyzed the substrate preferences of its mutants to identify the amino acid residues that determine the substrate specificity for α-(1→4)- and α-(1→6)-glucosidic linkages. The overall structure of FjGH97A resembles other GH97 enzymes, with conserved catalytic residues similar to anomer-inverting GH97 enzymes. A comparison of active sites between FjGH97A and SusB revealed differences in amino acid residues at subsites +1 and +2 (specifically Ala195 and Ile378 in FjGH97A). Among the three mutants (A195S, I378F, and A195S-I378F), A195S and A195S-I378F exhibited increased activity toward α-(1→4)-glucoside bonds compared to α-(1→6)-glucoside bonds. This suggests that Ala195, located on the Gly184-Thr203 loop (named loop-N) conserved within the GH97 subgroup, including FjGH97A and SusB, holds significance in determining linkage specificity. The conservation of alanine in the active site of the GH97 enzymes, within the same gene cluster as the putative dextranase, indicates its crucial role in determining the specificity for α-(1→6)-glucoside linkage.
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Affiliation(s)
- Shuntaro Nakamura
- Department of Bioscience, Graduate School of Science and Technology, Shizuoka University, Japan
| | - Rikuya Kurata
- Department of Agriculture, Graduate School of Integrated Science and Technology, Shizuoka University, Japan
| | - Takatsugu Miyazaki
- Department of Bioscience, Graduate School of Science and Technology, Shizuoka University, Japan
- Department of Agriculture, Graduate School of Integrated Science and Technology, Shizuoka University, Japan
- Research Institute of Green Science and Technology, Shizuoka University, Japan
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Macdonald JFH, Pérez-García P, Schneider YKH, Blümke P, Indenbirken D, Andersen JH, Krohn I, Streit WR. Community dynamics and metagenomic analyses reveal Bacteroidota's role in widespread enzymatic Fucus vesiculosus cell wall degradation. Sci Rep 2024; 14:10237. [PMID: 38702505 PMCID: PMC11068906 DOI: 10.1038/s41598-024-60978-8] [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: 11/13/2023] [Accepted: 04/29/2024] [Indexed: 05/06/2024] Open
Abstract
Enzymatic degradation of algae cell wall carbohydrates by microorganisms is under increasing investigation as marine organic matter gains more value as a sustainable resource. The fate of carbon in the marine ecosystem is in part driven by these degradation processes. In this study, we observe the microbiome dynamics of the macroalga Fucus vesiculosus in 25-day-enrichment cultures resulting in partial degradation of the brown algae. Microbial community analyses revealed the phylum Pseudomonadota as the main bacterial fraction dominated by the genera Marinomonas and Vibrio. More importantly, a metagenome-based Hidden Markov model for specific glycosyl hydrolyses and sulphatases identified Bacteroidota as the phylum with the highest potential for cell wall degradation, contrary to their low abundance. For experimental verification, we cloned, expressed, and biochemically characterised two α-L-fucosidases, FUJM18 and FUJM20. While protein structure predictions suggest the highest similarity to a Bacillota origin, protein-protein blasts solely showed weak similarities to defined Bacteroidota proteins. Both enzymes were remarkably active at elevated temperatures and are the basis for a potential synthetic enzyme cocktail for large-scale algal destruction.
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Affiliation(s)
- Jascha F H Macdonald
- Department of Microbiology and Biotechnology, Biocenter Klein Flottbek, Institute of Plant Science and Microbiology, University of Hamburg, Ohnhorststr.18, 22609, Hamburg, Germany
| | - Pablo Pérez-García
- Institute for General Microbiology, Molecular Microbiology, Kiel University, Kiel, Germany
| | - Yannik K-H Schneider
- Marbio, Faculty of Biosciences, Fisheries and Economics, UiT - The Arctic University of Norway, Tromsø, Norway
| | - Patrick Blümke
- Technology Platform Next Generation Sequencing, Leibniz Institute of Virology, Hamburg, Germany
| | - Daniela Indenbirken
- Technology Platform Next Generation Sequencing, Leibniz Institute of Virology, Hamburg, Germany
| | - Jeanette H Andersen
- Marbio, Faculty of Biosciences, Fisheries and Economics, UiT - The Arctic University of Norway, Tromsø, Norway
| | - Ines Krohn
- Department of Microbiology and Biotechnology, Biocenter Klein Flottbek, Institute of Plant Science and Microbiology, University of Hamburg, Ohnhorststr.18, 22609, Hamburg, Germany.
| | - Wolfgang R Streit
- Department of Microbiology and Biotechnology, Biocenter Klein Flottbek, Institute of Plant Science and Microbiology, University of Hamburg, Ohnhorststr.18, 22609, Hamburg, Germany
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Kalenborn S, Zühlke D, Riedel K, Amann RI, Harder J. Proteomic insight into arabinogalactan utilization by particle-associated Maribacter sp. MAR_2009_72. FEMS Microbiol Ecol 2024; 100:fiae045. [PMID: 38569650 PMCID: PMC11036162 DOI: 10.1093/femsec/fiae045] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2024] [Revised: 03/13/2024] [Accepted: 04/02/2024] [Indexed: 04/05/2024] Open
Abstract
Arabinose and galactose are major, rapidly metabolized components of marine particulate and dissolved organic matter. In this study, we observed for the first time large microbiomes for the degradation of arabinogalactan and report a detailed investigation of arabinogalactan utilization by the flavobacterium Maribacter sp. MAR_2009_72. Cellular extracts hydrolysed arabinogalactan in vitro. Comparative proteomic analyses of cells grown on arabinogalactan, arabinose, galactose, and glucose revealed the expression of specific proteins in the presence of arabinogalactan, mainly glycoside hydrolases (GH). Extracellular glycan hydrolysis involved five alpha-l-arabinofuranosidases affiliating with glycoside hydrolase families 43 and 51, four unsaturated rhamnogalacturonylhydrolases (GH105) and a protein with a glycoside hydrolase family-like domain. We detected expression of three induced TonB-dependent SusC/D transporter systems, one SusC, and nine glycoside hydrolases with a predicted periplasmatic location. These are affiliated with the families GH3, GH10, GH29, GH31, GH67, GH78, and GH115. The genes are located outside of and within canonical polysaccharide utilization loci classified as specific for arabinogalactan, for galactose-containing glycans, and for arabinose-containing glycans. The breadth of enzymatic functions expressed in Maribacter sp. MAR_2009_72 as response to arabinogalactan from the terrestrial plant larch suggests that Flavobacteriia are main catalysts of the rapid turnover of arabinogalactans in the marine environment.
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Affiliation(s)
- Saskia Kalenborn
- Department of Molecular Ecology, Max Planck Institute for Marine Microbiology, Celsiusstr. 1, D-28359 Bremen, Germany
| | - Daniela Zühlke
- Department for Microbial Physiology and Molecular Biology, University of Greifswald, Felix-Hausdorff-Str. 8, D-17489 Greifswald, Germany
| | - Katharina Riedel
- Department for Microbial Physiology and Molecular Biology, University of Greifswald, Felix-Hausdorff-Str. 8, D-17489 Greifswald, Germany
| | - Rudolf I Amann
- Department of Molecular Ecology, Max Planck Institute for Marine Microbiology, Celsiusstr. 1, D-28359 Bremen, Germany
| | - Jens Harder
- Department of Molecular Ecology, Max Planck Institute for Marine Microbiology, Celsiusstr. 1, D-28359 Bremen, Germany
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Do HE, Ha YB, Kim JS, Suh MK, Kim HS, Eom MK, Lee JH, Park SH, Kang SW, Lee DH, Yoon H, Lee JH, Lee JS. Phocaeicola acetigenes sp. nov., producing acetic acid and iso-butyric acid, isolated faeces from a healthy human. Antonie Van Leeuwenhoek 2024; 117:30. [PMID: 38302626 DOI: 10.1007/s10482-024-01930-8] [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: 08/14/2023] [Accepted: 01/20/2024] [Indexed: 02/03/2024]
Abstract
An obligately anaerobic, non-motile, Gram-stain-negative, and rod-shaped strain KGMB11183T was isolated from the feces of healthy Koreans. The growth of strain KGMB11183T occurred at 30-45 °C (optimum 37 °C), at pH 6-9 (optimum pH 7), and in the presence of 0-0.5% NaCl (optimum 0%). Strain KGMB11183T showed 16S rRNA gene sequence similarities of 95.4% and 94.2% to the closest recognized species, Phocaeicola plebeius M12T, and Phocaeicola faecicola AGMB03916T. Phylogenetic analysis showed that strain KGMB11183T is a member of the genus Phocaeiocla. The major end products of fermentation are acetic acid and isobutyric acid. The major cellular fatty acids (> 10%) of this isolate were C18:1 cis 9, anteiso-C15:0, and summed feature 11 (iso-C17:0 3-OH and/or C18:2 DMA). The assembled draft genome sequences of strain KGMB11183T consisted of 3,215,271 bp with a DNA G + C content of 41.4%. According to genomic analysis, strain KGMB11183T has a number of genes that produce acetic acid. The genome of strain KGMB11183T encoded the starch utilization system (Sus) operon, SusCDEF suggesting that strain uses many complex polysaccharides that cannot be digested by humans. Based on the physiological, chemotaxonomic, phenotypic, and phylogenetic data, strain KGMB11183T is regarded a novel species of the genus Phocaeicola. The type strain is KGMB11183T (= KCTC 25284T = JCM 35696T).
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Affiliation(s)
- Hyo Eun Do
- Korean Collection for Type Cultures, Korea Research Institute of Bioscience and Biotechnology, Jeongeup-si, Jeollabuk-do, 56212, Republic of Korea
- Department of Oriental Medicine Resources, Jeonbuk National University, 79 Gobong-ro, Iksan-si, Jeollabuk-do, 54596, Republic of Korea
| | - Young Bong Ha
- Korean Collection for Type Cultures, Korea Research Institute of Bioscience and Biotechnology, Jeongeup-si, Jeollabuk-do, 56212, Republic of Korea
| | - Ji-Sun Kim
- Korean Collection for Type Cultures, Korea Research Institute of Bioscience and Biotechnology, Jeongeup-si, Jeollabuk-do, 56212, Republic of Korea
| | - Min Kuk Suh
- Korean Collection for Type Cultures, Korea Research Institute of Bioscience and Biotechnology, Jeongeup-si, Jeollabuk-do, 56212, Republic of Korea
- Department of Lifestyle Medicine, Jeonbuk National University, 79 Gobong-ro, Iksan-si, Jeollabuk-do, 54596, Republic of Korea
| | - Han Sol Kim
- Korean Collection for Type Cultures, Korea Research Institute of Bioscience and Biotechnology, Jeongeup-si, Jeollabuk-do, 56212, Republic of Korea
- Department of Lifestyle Medicine, Jeonbuk National University, 79 Gobong-ro, Iksan-si, Jeollabuk-do, 54596, Republic of Korea
| | - Mi Kyung Eom
- Korean Collection for Type Cultures, Korea Research Institute of Bioscience and Biotechnology, Jeongeup-si, Jeollabuk-do, 56212, Republic of Korea
| | - Ju Huck Lee
- Korean Collection for Type Cultures, Korea Research Institute of Bioscience and Biotechnology, Jeongeup-si, Jeollabuk-do, 56212, Republic of Korea
| | - Seung-Hwan Park
- Korean Collection for Type Cultures, Korea Research Institute of Bioscience and Biotechnology, Jeongeup-si, Jeollabuk-do, 56212, Republic of Korea
| | - Se Won Kang
- Korean Collection for Type Cultures, Korea Research Institute of Bioscience and Biotechnology, Jeongeup-si, Jeollabuk-do, 56212, Republic of Korea
| | - Dong Ho Lee
- Seoul National University Bundang Hospital, 82 Gumi-ro, 173 Beon-Gil, Bundang-gu, Seongnam-si, Gyeonggi-do, 13620, Republic of Korea
| | - Hyuk Yoon
- Seoul National University Bundang Hospital, 82 Gumi-ro, 173 Beon-Gil, Bundang-gu, Seongnam-si, Gyeonggi-do, 13620, Republic of Korea
| | - Je Hee Lee
- CJ Bioscience, Inc., 14 Sejong-Daero, Jung-gu, Seoul, 04527, Republic of Korea
| | - Jung-Sook Lee
- Korean Collection for Type Cultures, Korea Research Institute of Bioscience and Biotechnology, Jeongeup-si, Jeollabuk-do, 56212, Republic of Korea.
- University of Science and Technology (UST), 217 Gajeong-ro, Yuseong-gu, Daejeon, 34113, Republic of Korea.
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Amir SE, Naeem M, Boocock D, Coveney C, O'Neill HM, Bedford MR, Burton EJ. Xylo-oligosaccharide-based prebiotics upregulate the proteins of the Sus-like system in caecal Bacteroidetes of the chicken: evidence of stimbiotic mechanism. Poult Sci 2023; 102:103113. [PMID: 37856910 PMCID: PMC10590740 DOI: 10.1016/j.psj.2023.103113] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 08/30/2023] [Accepted: 09/09/2023] [Indexed: 10/21/2023] Open
Abstract
The present study was conducted to investigate the stimbiotic mechanism of xylo-oligosaccharide (XOS) in degrading the complex polysaccharides by the caecal bacteria of the chicken, by applying a proteomic approach. A total of 800 as-hatched Ross 308 broiler chicks were equally divided into 4 experimental pens (200 chicks per pen) at a commercial poultry barn, allocating 2 pens per treatment. Birds were fed ad libitum with 2 dietary treatments; CON (without XOS) and XOS (with 0.1g XOS/kg diet) from d 0 to 35. From each pen, 60 Individual birds were weighed weekly whereas caecal content was obtained from 5 birds cervically dislocated on d 35. The caecal bacteria were lysed and their proteins were quantified using label-free quantitative proteomic mass spectrometry. The results showed that XOS significantly increased (P < 0.05) bird weight on d 7, 14, 21, and 28, and body weight gain on d 7, 14, 21, and 35 compared to CON. However, no difference (P > 0.05) in body weight gain was observed from d 0 to 35 between CON and XOS. The proteomic analysis of caecal bacteria revealed that 29 proteins were expressed differently between the CON and the XOS group. Out of 29, 20 proteins were significantly increased in the XOS group compared to CON and 9 of those proteins belonged to the starch-utilizing system (Sus)-like system of the gram-negative Bacteroidetes. Bacteroides thetaiotaomicron (Bt) is a significant constituent of the human gut microbiota, known for its remarkable ability to hydrolyze most glycosidic bonds of polysaccharides. This microorganism possesses a 5-protein complex in its outer membrane, named the starch utilization system (Sus), responsible for adhering to, breaking down, and transporting starch into the cell. Sus serves as an exemplar system for numerous polysaccharide utilization loci that target glycans found in Bt and other members of the Bacteroidetes phylum. The proteins of the Sus-like system are involved in the degradation of complex polysaccharides and transportation of the oligosaccharides into the periplasm of the caecal bacteria where they are further broken down into smaller units. These smaller units are then transported into the cytoplasm of the cell where they are utilized in metabolic pathways leading to potential generation of short-chain fatty acids, thus improving the nutritive value of residual feed. In conclusion, XOS supplementation upregulates the expression of the proteins of the Sus-like system indicating its role as a stimbiotic.
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Affiliation(s)
- Saba E Amir
- School of Animal, Rural and Environmental Sciences, Nottingham Trent University, Nottingham, NG25 0QF, United Kingdom
| | - M Naeem
- School of Animal, Rural and Environmental Sciences, Nottingham Trent University, Nottingham, NG25 0QF, United Kingdom.
| | - David Boocock
- School of Science and Technology, Nottingham Trent University, Nottingham NG11 8NF, United Kingdom
| | - Clare Coveney
- School of Science and Technology, Nottingham Trent University, Nottingham NG11 8NF, United Kingdom
| | - H M O'Neill
- AB Vista, Marlborough, SN8 4AN, United Kingdom
| | - M R Bedford
- AB Vista, Marlborough, SN8 4AN, United Kingdom
| | - E J Burton
- School of Animal, Rural and Environmental Sciences, Nottingham Trent University, Nottingham, NG25 0QF, United Kingdom
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9
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Nakamura S, Kurata R, Tonozuka T, Funane K, Park EY, Miyazaki T. Bacteroidota polysaccharide utilization system for branched dextran exopolysaccharides from lactic acid bacteria. J Biol Chem 2023:104885. [PMID: 37269952 PMCID: PMC10316084 DOI: 10.1016/j.jbc.2023.104885] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 05/25/2023] [Accepted: 05/26/2023] [Indexed: 06/05/2023] Open
Abstract
Dextran is an α-(1→6)-glucan that is synthesized by some lactic acid bacteria, and branched dextran with α-(1→2)-, α-(1→3)-, and α-(1→4)-linkages are often produced. Although many dextranases are known to act on the α-(1→6)-linkage of dextran, few studies have functionally analyzed the proteins involved in degrading branched dextran. The mechanism by which bacteria utilize branched dextran is unknown. Earlier, we identified dextranase (FjDex31A) and kojibiose hydrolase (FjGH65A) in the dextran utilization locus (FjDexUL) of a soil Bacteroidota Flavobacterium johnsoniae and hypothesized that FjDexUL is involved in the degradation of α-(1→2)-branched dextran. In this study, we demonstrate that FjDexUL proteins recognize and degrade α-(1→2)- and α-(1→3)-branched dextrans produced by Leuconostoc citreum S-32 (S-32 α-glucan). The FjDexUL gene was significantly upregulated when S-32 α-glucan was the carbon source compared with α-glucooligosaccharides and α-glucans, such as linear dextran and branched α-glucan from L. citreum S-64. FjDexUL GHs synergistically degraded S-32 α-glucan. The crystal structure of FjGH66 shows that some sugar-binding subsites can accommodate α-(1→2)- and α-(1→3)-branches. The structure of FjGH65A in complex with isomaltose supports that FjGH65A acts on α-(1→2)-glucosyl isomaltooligosaccharides. Furthermore, two cell surface sugar-binding proteins (FjDusD and FjDusE) were characterized, and FjDusD showed affinity for isomaltooligosaccharides and FjDusE for dextran, including linear and branched dextrans. Collectively, FjDexUL proteins are suggested to be involved in the degradation of α-(1→2)- and α-(1→3)-branched dextrans. Our results will be helpful in understanding the bacterial nutrient requirements and symbiotic relationships between bacteria at the molecular level.
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Affiliation(s)
- Shuntaro Nakamura
- Department of Bioscience, Graduate School of Science and Technology, Shizuoka University, 836 Ohya Suruga-ku, Shizuoka 422-8529, Japan
| | - Rikuya Kurata
- Department of Agriculture, Graduate School of Integrated Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529, Japan
| | - Takashi Tonozuka
- Department of Applied Biological Science, Tokyo University of Agriculture and Technology, 3-5-8 Saiwai-cho, Fuchu, Tokyo, 183-8509, Japan
| | - Kazumi Funane
- Faculty of Life and Environmental Sciences, University of Yamanashi, 4-4-37, Takeda-cho, Kofu, Yamanashi, 400-8510, Japan
| | - Enoch Y Park
- Department of Bioscience, Graduate School of Science and Technology, Shizuoka University, 836 Ohya Suruga-ku, Shizuoka 422-8529, Japan; Department of Agriculture, Graduate School of Integrated Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529, Japan; Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529, Japan
| | - Takatsugu Miyazaki
- Department of Bioscience, Graduate School of Science and Technology, Shizuoka University, 836 Ohya Suruga-ku, Shizuoka 422-8529, Japan; Department of Agriculture, Graduate School of Integrated Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529, Japan; Research Institute of Green Science and Technology, Shizuoka University, 836 Ohya, Suruga-ku, Shizuoka, 422-8529, Japan.
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10
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Hu X, Li Y, Wu J, Zhang H, Huang Y, Tan X, Wen L, Zhou X, Xie P, Olasunkanmi OI, Zhou J, Sun Z, Liu M, Zhang G, Yang J, Zheng P, Xie P. Changes of gut microbiota reflect the severity of major depressive disorder: a cross sectional study. Transl Psychiatry 2023; 13:137. [PMID: 37117202 PMCID: PMC10147706 DOI: 10.1038/s41398-023-02436-z] [Citation(s) in RCA: 15] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 09/30/2022] [Revised: 04/15/2023] [Accepted: 04/18/2023] [Indexed: 04/30/2023] Open
Abstract
Disturbed gut microbiota is a potential factor in the pathogenesis of major depressive disorder (MDD), yet whether gut microbiota dysbiosis is associated with the severity of MDD remains unclear. Here, we performed shotgun metagenomic profiling of cross-sectional stool samples from MDD (n = 138) and healthy controls (n = 155). The patients with MDD were divided into three groups according to Hamilton Depression Rating Scale 17 (HAMD-17), including mild (n = 24), moderate (n = 72) and severe (n = 42) individuals, respectively. We found that microbial diversity was closely related to the severity of MDD. Compared to HCs, the abundance of Bacteroides was significantly increased in both moderate and severe MDD, while Ruminococcus and Eubacterium depleted mainly in severe group. In addition, we identified 99 bacteria species specific to severity of depression. Furthermore, a panel of microbiota marker comprising of 37 bacteria species enabled to effectively distinguish MDD patients with different severity. Together, we identified different perturbation patterns of gut microbiota in mild-to-severe depression, and identified potential diagnostic and therapeutic targets.
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Affiliation(s)
- Xi Hu
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- NHC Key Laboratory of Diagnosis and Treatment on Brain Functional Diseases, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Yifan Li
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- NHC Key Laboratory of Diagnosis and Treatment on Brain Functional Diseases, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Jing Wu
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- NHC Key Laboratory of Diagnosis and Treatment on Brain Functional Diseases, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Hanping Zhang
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- NHC Key Laboratory of Diagnosis and Treatment on Brain Functional Diseases, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Yu Huang
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- NHC Key Laboratory of Diagnosis and Treatment on Brain Functional Diseases, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Xunmin Tan
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- NHC Key Laboratory of Diagnosis and Treatment on Brain Functional Diseases, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Lu Wen
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- NHC Key Laboratory of Diagnosis and Treatment on Brain Functional Diseases, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Xingyu Zhou
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- NHC Key Laboratory of Diagnosis and Treatment on Brain Functional Diseases, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | - Peijun Xie
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
- NHC Key Laboratory of Diagnosis and Treatment on Brain Functional Diseases, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China
| | | | - Jingjing Zhou
- Beijing Key Laboratory of Mental Disorders, National Clinical Research Center for Mental Disorders & National Center for Mental Disorders, Beijing Anding Hospital, Capital Medical University, Beijing, China
- Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing, China
| | - Zuoli Sun
- Beijing Key Laboratory of Mental Disorders, National Clinical Research Center for Mental Disorders & National Center for Mental Disorders, Beijing Anding Hospital, Capital Medical University, Beijing, China
- Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing, China
| | - Min Liu
- Beijing Key Laboratory of Mental Disorders, National Clinical Research Center for Mental Disorders & National Center for Mental Disorders, Beijing Anding Hospital, Capital Medical University, Beijing, China
- Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing, China
| | - Guofu Zhang
- Beijing Key Laboratory of Mental Disorders, National Clinical Research Center for Mental Disorders & National Center for Mental Disorders, Beijing Anding Hospital, Capital Medical University, Beijing, China
- Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing, China
| | - Jian Yang
- Beijing Key Laboratory of Mental Disorders, National Clinical Research Center for Mental Disorders & National Center for Mental Disorders, Beijing Anding Hospital, Capital Medical University, Beijing, China.
- Advanced Innovation Center for Human Brain Protection, Capital Medical University, Beijing, China.
| | - Peng Zheng
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
- NHC Key Laboratory of Diagnosis and Treatment on Brain Functional Diseases, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
| | - Peng Xie
- Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
- NHC Key Laboratory of Diagnosis and Treatment on Brain Functional Diseases, The First Affiliated Hospital of Chongqing Medical University, Chongqing, China.
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11
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Shagaleeva OY, Kashatnikova DA, Kardonsky DA, Konanov DN, Efimov BA, Bagrov DV, Evtushenko EG, Chaplin AV, Silantiev AS, Filatova JV, Kolesnikova IV, Vanyushkina AA, Stimpson J, Zakharzhevskaya NB. Investigating volatile compounds in the Bacteroides secretome. Front Microbiol 2023; 14:1164877. [PMID: 37206326 PMCID: PMC10189065 DOI: 10.3389/fmicb.2023.1164877] [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: 02/13/2023] [Accepted: 04/14/2023] [Indexed: 05/21/2023] Open
Abstract
Microorganisms and their hosts communicate with each other by secreting numerous components. This cross-kingdom cell-to-cell signaling involves proteins and small molecules, such as metabolites. These compounds can be secreted across the membrane via numerous transporters and may also be packaged in outer membrane vesicles (OMVs). Among the secreted components, volatile compounds (VOCs) are of particular interest, including butyrate and propionate, which have proven effects on intestinal, immune, and stem cells. Besides short fatty acids, other groups of volatile compounds can be either freely secreted or contained in OMVs. As vesicles might extend their activity far beyond the gastrointestinal tract, study of their cargo, including VOCs, is even more pertinent. This paper is devoted to the VOCs secretome of the Bacteroides genus. Although these bacteria are highly presented in the intestinal microbiota and are known to influence human physiology, their volatile secretome has been studied relatively poorly. The 16 most well-represented Bacteroides species were cultivated; their OMVs were isolated and characterized by NTA and TEM to determine particle morphology and their concentration. In order to analyze the VOCs secretome, we propose a headspace extraction with GC-MS analysis as a new tool for sample preparation and analysis of volatile compounds in culture media and isolated bacterial OMVs. A wide range of released VOCs, both previously characterized and newly described, have been revealed in media after cultivation. We identified more than 60 components of the volatile metabolome in bacterial media, including fatty acids, amino acids, and phenol derivatives, aldehydes and other components. We found active butyrate and indol producers among the analyzed Bacteroides species. For a number of Bacteroides species, OMVs have been isolated and characterized here for the first time as well as volatile compounds analysis in OMVs. We observed a completely different distribution of VOC in vesicles compared to the bacterial media for all analyzed Bacteroides species, including almost complete absence of fatty acids in vesicles. This article provides a comprehensive analysis of the VOCs secreted by Bacteroides species and explores new perspectives in the study of bacterial secretomes in relation the intercellular communication.
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Affiliation(s)
- Olga Yu Shagaleeva
- Laboratory of Molecular Pathophysiology, Lopukhin Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, Russia
| | - Daria A. Kashatnikova
- Laboratory of Molecular Pathophysiology, Lopukhin Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, Russia
| | - Dmitry A. Kardonsky
- Laboratory of Molecular Pathophysiology, Lopukhin Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, Russia
| | - Dmitry N. Konanov
- Laboratory of Mathematical Biology and Bioinformatics of Scientific Research Institute for Systems Biology and Medicine, Moscow, Russia
| | - Boris A. Efimov
- Laboratory of Molecular Pathophysiology, Lopukhin Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, Russia
- Department of Microbiology and Virology, Pirogov Russian National Research Medical University, Moscow, Russia
| | - Dmitry V. Bagrov
- Department of Bioengineering, Faculty of Biology, Lomonosov Moscow State University, Moscow, Russia
| | | | - Andrei V. Chaplin
- Department of Microbiology and Virology, Pirogov Russian National Research Medical University, Moscow, Russia
| | - Artemiy S. Silantiev
- Laboratory of Molecular Pathophysiology, Lopukhin Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, Russia
| | - Julia V. Filatova
- Laboratory of Molecular Pathophysiology, Lopukhin Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, Russia
| | - Irina V. Kolesnikova
- Laboratory of Molecular Pathophysiology, Lopukhin Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, Russia
| | - Anna A. Vanyushkina
- Vladimir Zelman Center for Neurobiology and Brain Rehabilitation, Skolkovo Institute of Science and Technology, Moscow, Russia
| | - Joanna Stimpson
- School of Health Sciences, Faculty of Biology, Medicine and Health, University of Manchester, Manchester, United Kingdom
| | - Natalya B. Zakharzhevskaya
- Laboratory of Molecular Pathophysiology, Lopukhin Federal Research and Clinical Center of Physical-Chemical Medicine of Federal Medical Biological Agency, Moscow, Russia
- *Correspondence: Natalya B. Zakharzhevskaya,
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12
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Fox E, Lyte M. Variation in spatial organization of the gut microbiota along the longitudinal and transverse axes of the intestines. Arch Microbiol 2022; 204:424. [PMID: 35750957 DOI: 10.1007/s00203-022-02952-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2021] [Revised: 04/25/2022] [Accepted: 04/28/2022] [Indexed: 11/02/2022]
Abstract
Elucidation of the mechanisms by which the microbiota-gut-brain axis influences behavior requires understanding the anatomical relationship of bacteria with mucosal elements. We herein report that microbes were mainly associated with food or fecal matter in the intestinal lumen. In the small intestine, bacterial density increased from proximal-to-distal levels and was much higher in the large intestine. A mucus layer was present between the mucosal epithelium and fecal boluses in the large intestine, but not between food and the mucosal epithelium in the small intestine. In contrast, in all intestinal regions lacking food or fecal boluses, the lumen was small, or absent, and contained little or no bacteria or mucus. The association of bacteria with food was tested in the small intestine by examining the effect of fasting on it. Bacterial density was equivalent in the ileum of fasted and fed mice, but fasting greatly reduced the amount of food containing bacteria, suggesting the amount of bacteria was reduced. Critically, this study provides evidence that the vast majority of the microbiota in the intestines are associated with the food matrix thereby raising questions regarding how the gut microbiota can potentially signal the brain and influence behavior. Given their spatial location within the lumen, which keeps them at a great distance from neuronal elements in the mucosa, combined with immune and mucus barriers, microbiota more likely to influence behavior through secretion of bacterial products that can traverse the spatial difference to interact with gut neurons and not through direct physical association.
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Affiliation(s)
- Edward Fox
- Department of Psychological Sciences, Purdue University, 703 Third Street, West Lafayette, IN, 47907, USA.
| | - Mark Lyte
- Department of Veterinary Microbiology and Preventive Medicine, Iowa State University, Ames, IA, 50011, USA
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13
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Bacteroides humanifaecis sp. nov., isolated from faeces of healthy Korean. Arch Microbiol 2022; 204:357. [DOI: 10.1007/s00203-022-02967-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2021] [Accepted: 05/09/2022] [Indexed: 11/02/2022]
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14
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Zhang Y, Bhosle A, Bae S, McIver LJ, Pishchany G, Accorsi EK, Thompson KN, Arze C, Wang Y, Subramanian A, Kearney SM, Pawluk A, Plichta DR, Rahnavard A, Shafquat A, Xavier RJ, Vlamakis H, Garrett WS, Krueger A, Huttenhower C, Franzosa EA. Discovery of bioactive microbial gene products in inflammatory bowel disease. Nature 2022; 606:754-760. [PMID: 35614211 PMCID: PMC9913614 DOI: 10.1038/s41586-022-04648-7] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2020] [Accepted: 03/15/2022] [Indexed: 01/26/2023]
Abstract
Microbial communities and their associated bioactive compounds1-3 are often disrupted in conditions such as the inflammatory bowel diseases (IBD)4. However, even in well-characterized environments (for example, the human gastrointestinal tract), more than one-third of microbial proteins are uncharacterized and often expected to be bioactive5-7. Here we systematically identified more than 340,000 protein families as potentially bioactive with respect to gut inflammation during IBD, about half of which have not to our knowledge been functionally characterized previously on the basis of homology or experiment. To validate prioritized microbial proteins, we used a combination of metagenomics, metatranscriptomics and metaproteomics to provide evidence of bioactivity for a subset of proteins that are involved in host and microbial cell-cell communication in the microbiome; for example, proteins associated with adherence or invasion processes, and extracellular von Willebrand-like factors. Predictions from high-throughput data were validated using targeted experiments that revealed the differential immunogenicity of prioritized Enterobacteriaceae pilins and the contribution of homologues of von Willebrand factors to the formation of Bacteroides biofilms in a manner dependent on mucin levels. This methodology, which we term MetaWIBELE (workflow to identify novel bioactive elements in the microbiome), is generalizable to other environmental communities and human phenotypes. The prioritized results provide thousands of candidate microbial proteins that are likely to interact with the host immune system in IBD, thus expanding our understanding of potentially bioactive gene products in chronic disease states and offering a rational compendium of possible therapeutic compounds and targets.
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Affiliation(s)
- Yancong Zhang
- Infectious Disease and Microbiome Program, Broad Institute of MIT and Harvard, Cambridge, MA, USA,Department of Biostatistics, Harvard T. H. Chan School of Public Health, Boston, MA, USA,Harvard Chan Microbiome in Public Health Center, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - Amrisha Bhosle
- Infectious Disease and Microbiome Program, Broad Institute of MIT and Harvard, Cambridge, MA, USA,Department of Biostatistics, Harvard T. H. Chan School of Public Health, Boston, MA, USA,Harvard Chan Microbiome in Public Health Center, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - Sena Bae
- Department of Biostatistics, Harvard T. H. Chan School of Public Health, Boston, MA, USA,Harvard Chan Microbiome in Public Health Center, Harvard T. H. Chan School of Public Health, Boston, MA, USA,Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - Lauren J. McIver
- Department of Biostatistics, Harvard T. H. Chan School of Public Health, Boston, MA, USA,Harvard Chan Microbiome in Public Health Center, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - Gleb Pishchany
- Infectious Disease and Microbiome Program, Broad Institute of MIT and Harvard, Cambridge, MA, USA,Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA, USA
| | - Emma K. Accorsi
- Department of Biostatistics, Harvard T. H. Chan School of Public Health, Boston, MA, USA,Harvard Chan Microbiome in Public Health Center, Harvard T. H. Chan School of Public Health, Boston, MA, USA,Center for Communicable Disease Dynamics, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - Kelsey N. Thompson
- Infectious Disease and Microbiome Program, Broad Institute of MIT and Harvard, Cambridge, MA, USA,Department of Biostatistics, Harvard T. H. Chan School of Public Health, Boston, MA, USA,Harvard Chan Microbiome in Public Health Center, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - Cesar Arze
- Department of Biostatistics, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - Ya Wang
- Infectious Disease and Microbiome Program, Broad Institute of MIT and Harvard, Cambridge, MA, USA,Department of Biostatistics, Harvard T. H. Chan School of Public Health, Boston, MA, USA,Harvard Chan Microbiome in Public Health Center, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - Ayshwarya Subramanian
- Infectious Disease and Microbiome Program, Broad Institute of MIT and Harvard, Cambridge, MA, USA,Department of Biostatistics, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - Sean M. Kearney
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - April Pawluk
- Department of Biostatistics, Harvard T. H. Chan School of Public Health, Boston, MA, USA,Harvard Chan Microbiome in Public Health Center, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - Damian R. Plichta
- Infectious Disease and Microbiome Program, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Ali Rahnavard
- Infectious Disease and Microbiome Program, Broad Institute of MIT and Harvard, Cambridge, MA, USA,Department of Biostatistics, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - Afrah Shafquat
- Infectious Disease and Microbiome Program, Broad Institute of MIT and Harvard, Cambridge, MA, USA,Department of Biostatistics, Harvard T. H. Chan School of Public Health, Boston, MA, USA
| | - Ramnik J. Xavier
- Infectious Disease and Microbiome Program, Broad Institute of MIT and Harvard, Cambridge, MA, USA,Gastrointestinal Unit and Center for the Study of Inflammatory Bowel Disease, Massachusetts General Hospital and Harvard Medical School, Boston, MA, USA,Center for Microbiome Informatics and Therapeutics, Massachusetts Institute of Technology, Cambridge, MA, USA
| | - Hera Vlamakis
- Infectious Disease and Microbiome Program, Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Wendy S. Garrett
- Infectious Disease and Microbiome Program, Broad Institute of MIT and Harvard, Cambridge, MA, USA,Harvard Chan Microbiome in Public Health Center, Harvard T. H. Chan School of Public Health, Boston, MA, USA,Department of Immunology and Infectious Diseases, Harvard T. H. Chan School of Public Health, Boston, MA, USA,Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, MA, USA
| | - Andy Krueger
- Takeda Pharmaceutical Company Limited, Cambridge, MA, USA
| | - Curtis Huttenhower
- Infectious Disease and Microbiome Program, Broad Institute of MIT and Harvard, Cambridge, MA, USA. .,Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA, USA. .,Harvard Chan Microbiome in Public Health Center, Harvard T.H. Chan School of Public Health, Boston, MA, USA. .,Department of Immunology and Infectious Diseases, Harvard T.H. Chan School of Public Health, Boston, MA, USA.
| | - Eric A. Franzosa
- Infectious Disease and Microbiome Program, Broad Institute of MIT and Harvard, Cambridge, MA, USA,Department of Biostatistics, Harvard T. H. Chan School of Public Health, Boston, MA, USA,Harvard Chan Microbiome in Public Health Center, Harvard T. H. Chan School of Public Health, Boston, MA, USA,These authors jointly supervised this work: Curtis Huttenhower & Eric A. Franzosa
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15
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Thirion F, Da Silva K, Plaza Oñate F, Alvarez A, Thabuis C, Pons N, Berland M, Le Chatelier E, Galleron N, Levenez F, Vergara C, Chevallier H, Guérin‐Deremaux L, Doré J, Ehrlich SD. Diet Supplementation with NUTRIOSE, a Resistant Dextrin, Increases the Abundance of Parabacteroides distasonis in the Human Gut. Mol Nutr Food Res 2022; 66:e2101091. [PMID: 35312171 PMCID: PMC9287035 DOI: 10.1002/mnfr.202101091] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2021] [Revised: 02/25/2022] [Indexed: 12/18/2022]
Abstract
SCOPE An imbalance of the gut microbiota ("dysbiosis") is associated with numerous chronic diseases, and its modulation is a promising novel therapeutic approach. Dietary supplementation with soluble fiber is one of several proposed modulation strategies. This study aims at confirming the impact of the resistant dextrin NUTRIOSE (RD), a soluble fiber with demonstrated beneficial health effects, on the gut microbiota of healthy individuals. METHODS AND RESULTS Fifty healthy women are enrolled and supplemented daily with either RD (n = 24) or a control product (n = 26) during 6 weeks. Characterization of the fecal metagenome with shotgun sequencing reveals that RD intake dramatically increases the abundance of the commensal bacterium Parabacteroides distasonis. Furthermore, presence in metagenomes of accessory genes from P. distasonis, coding for susCD (a starch-binding membrane protein complex) is associated with a greater increase of the species. This suggests that response to RD might be strain-dependent. CONCLUSION Supplementation with RD can be used to specifically increase P. distasonis in gut microbiota of healthy women. The magnitude of the response may be associated with fiber-metabolizing capabilities of strains carried by subjects. Further research will seek to confirm that P. distasonis directly modulates the clinical effects observed in other studies.
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Affiliation(s)
| | | | | | | | | | - Nicolas Pons
- INRAEMGPUniversité Paris‐SaclayJouy‐en‐Josas78350France
| | | | | | | | | | | | | | | | - Joël Doré
- INRAEMGPUniversité Paris‐SaclayJouy‐en‐Josas78350France
- INRAEAgroParisTechMicalis InstituteUniversité Paris‐SaclayJouy‐en‐Josas78350France
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16
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Rawat PS, Seyed Hameed AS, Meng X, Liu W. Utilization of glycosaminoglycans by the human gut microbiota: participating bacteria and their enzymatic machineries. Gut Microbes 2022; 14:2068367. [PMID: 35482895 PMCID: PMC9067506 DOI: 10.1080/19490976.2022.2068367] [Citation(s) in RCA: 35] [Impact Index Per Article: 17.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Glycosaminoglycans (GAGs) are consistently present in the human colon in free forms and as part of proteoglycans. Their utilization is critical for the colonization and proliferation of gut bacteria and also the health of hosts. Hence, it is essential to determine the GAG-degrading members of the gut bacteria and their enzymatic machinery for GAG depolymerization. In this review, we have summarized the reported GAG utilizers from Bacteroides and presented their polysaccharide utilization loci (PUL) and related enzymatic machineries for the degradation of chondroitin and heparin/heparan sulfate. Although similar comprehensive knowledge of GAG degradation is not available for other gut phyla, we have specified recently isolated GAG degraders from gut Firmicutes and Proteobacteria, and analyzed their genomes for the presence of putative GAG PULs. Deciphering the precise GAG utilization mechanism for various phyla will augment our understanding of their effects on human health.
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Affiliation(s)
- Parkash Singh Rawat
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No.72 Binhai Road, Qingdao266237, P. R. China
| | - Ahkam Saddam Seyed Hameed
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No.72 Binhai Road, Qingdao266237, P. R. China
| | - Xiangfeng Meng
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No.72 Binhai Road, Qingdao266237, P. R. China,CONTACT Xiangfeng Meng State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No.72 Binhai Road, Qingdao266237, P. R. China
| | - Weifeng Liu
- State Key Laboratory of Microbial Technology, Microbial Technology Institute, Shandong University, No.72 Binhai Road, Qingdao266237, P. R. China
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17
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Pudlo NA, Urs K, Crawford R, Pirani A, Atherly T, Jimenez R, Terrapon N, Henrissat B, Peterson D, Ziemer C, Snitkin E, Martens EC. Phenotypic and Genomic Diversification in Complex Carbohydrate-Degrading Human Gut Bacteria. mSystems 2022; 7:e0094721. [PMID: 35166563 PMCID: PMC8845570 DOI: 10.1128/msystems.00947-21] [Citation(s) in RCA: 31] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2021] [Accepted: 01/04/2022] [Indexed: 12/20/2022] Open
Abstract
Symbiotic bacteria are responsible for the majority of complex carbohydrate digestion in the human colon. Since the identities and amounts of dietary polysaccharides directly impact the gut microbiota, determining which microorganisms consume specific nutrients is central for defining the relationship between diet and gut microbial ecology. Using a custom phenotyping array, we determined carbohydrate utilization profiles for 354 members of the Bacteroidetes, a dominant saccharolytic phylum. There was wide variation in the numbers and types of substrates degraded by individual bacteria, but phenotype-based clustering grouped members of the same species indicating that each species performs characteristic roles. The ability to utilize dietary polysaccharides and endogenous mucin glycans was negatively correlated, suggesting exclusion between these niches. By analyzing related Bacteroides ovatus/Bacteroides xylanisolvens strains that vary in their ability to utilize mucin glycans, we addressed whether gene clusters that confer this complex, multilocus trait are being gained or lost in individual strains. Pangenome reconstruction of these strains revealed a remarkably mosaic architecture in which genes involved in polysaccharide metabolism are highly variable and bioinformatics data provide evidence of interspecies gene transfer that might explain this genomic heterogeneity. Global transcriptomic analyses suggest that the ability to utilize mucin has been lost in some lineages of B. ovatus and B. xylanisolvens, which harbor residual gene clusters that are involved in mucin utilization by strains that still actively express this phenotype. Our data provide insight into the breadth and complexity of carbohydrate metabolism in the microbiome and the underlying genomic events that shape these behaviors. IMPORTANCE Nonharmful bacteria are the primary microbial symbionts that inhabit the human gastrointestinal tract. These bacteria play many beneficial roles and in some cases can modify disease states, making it important to understand which nutrients sustain specific lineages. This knowledge will in turn lead to strategies to intentionally manipulate the gut microbial ecosystem. We designed a scalable, high-throughput platform for measuring the ability of gut bacteria to utilize polysaccharides, of which many are derived from dietary fiber sources that can be manipulated easily. Our results provide paths to expand phenotypic surveys of more diverse gut bacteria to understand their functions and also to leverage dietary fibers to alter the physiology of the gut microbial community.
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Affiliation(s)
- Nicholas A. Pudlo
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Karthik Urs
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Ryan Crawford
- Department of Computational Medicine and Bioinformatics, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Ali Pirani
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Todd Atherly
- Iowa State University, Department of Animal Science, Ames, Iowa, USA
- United States Department of Agriculture Agricultural Research Station, Ames, Iowa, USA
| | - Roberto Jimenez
- University of Nebraska, Department of Food Sciences, Lincoln, Nebraska, USA
| | - Nicolas Terrapon
- Aix Marseille Univ, CNRS, UMR7257 AFMB, Marseille, France
- INRAE, USC1408 AFMB, Marseille, France
| | - Bernard Henrissat
- Aix Marseille Univ, CNRS, UMR7257 AFMB, Marseille, France
- INRAE, USC1408 AFMB, Marseille, France
- Department of Biological Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Daniel Peterson
- University of Nebraska, Department of Food Sciences, Lincoln, Nebraska, USA
- Johns Hopkins University, Department of Pathology, Baltimore, Maryland, USA
| | - Cherie Ziemer
- Iowa State University, Department of Animal Science, Ames, Iowa, USA
- United States Department of Agriculture Agricultural Research Station, Ames, Iowa, USA
| | - Evan Snitkin
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
| | - Eric C. Martens
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan, USA
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18
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Feng J, Qian Y, Zhou Z, Ertmer S, Vivas EI, Lan F, Hamilton JJ, Rey FE, Anantharaman K, Venturelli OS. Polysaccharide utilization loci in Bacteroides determine population fitness and community-level interactions. Cell Host Microbe 2022; 30:200-215.e12. [PMID: 34995484 PMCID: PMC9060796 DOI: 10.1016/j.chom.2021.12.006] [Citation(s) in RCA: 37] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/04/2021] [Revised: 08/22/2021] [Accepted: 12/07/2021] [Indexed: 02/06/2023]
Abstract
Polysaccharide utilization loci (PULs) are co-regulated bacterial genes that sense nutrients and enable glycan digestion. Human gut microbiome members, notably Bacteroides, contain numerous PULs that enable glycan utilization and shape ecological dynamics. To investigate the role of PULs on fitness and inter-species interactions, we develop a CRISPR-based genome editing tool to study 23 PULs in Bacteroides uniformis (BU). BU PULs show distinct glycan-degrading functions and transcriptional coordination that enables the population to adapt upon loss of other PULs. Exploiting a BU mutant barcoding strategy, we demonstrate that in vitro fitness and BU colonization in the murine gut are enhanced by deletion of specific PULs and modulated by glycan availability. PULs mediate glycan-dependent interactions with butyrate producers that depend on the degradation mechanism and glycan utilization ability of the butyrate producer. Thus, PULs determine community dynamics and butyrate production and provide a selective advantage or disadvantage depending on the nutritional landscape.
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Affiliation(s)
- Jun Feng
- The Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI 53706, USA,Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Yili Qian
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Zhichao Zhou
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Sarah Ertmer
- Department of Chemical & Biological Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Eugenio I. Vivas
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI 53706, USA,Gnotobiotic Animal Core Facility, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Freeman Lan
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Joshua J. Hamilton
- Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Federico E. Rey
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Karthik Anantharaman
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Ophelia S. Venturelli
- The Great Lakes Bioenergy Research Center, University of Wisconsin-Madison, Madison, WI 53706, USA,Department of Biochemistry, University of Wisconsin-Madison, Madison, WI 53706, USA,Department of Bacteriology, University of Wisconsin-Madison, Madison, WI 53706, USA,Department of Chemical & Biological Engineering, University of Wisconsin-Madison, Madison, WI 53706, USA,Lead contact,Correspondence:
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19
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Li J, Gálvez EJC, Amend L, Almási É, Iljazovic A, Lesker TR, Bielecka AA, Schorr EM, Strowig T. A versatile genetic toolbox for Prevotella copri enables studying polysaccharide utilization systems. EMBO J 2021; 40:e108287. [PMID: 34676563 PMCID: PMC8634118 DOI: 10.15252/embj.2021108287] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2021] [Revised: 09/08/2021] [Accepted: 09/24/2021] [Indexed: 12/30/2022] Open
Abstract
Prevotella copri is a prevalent inhabitant of the human gut and has been associated with plant‐rich diet consumption and diverse health states. The underlying genetic basis of these associations remains enigmatic due to the lack of genetic tools. Here, we developed a novel versatile genetic toolbox for rapid and efficient genetic insertion and allelic exchange applicable to P. copri strains from multiple clades. Enabled by the genetic platform, we systematically investigated the specificity of polysaccharide utilization loci (PULs) and identified four highly conserved PULs for utilizing arabinan, pectic galactan, arabinoxylan, and inulin, respectively. Further genetic and functional analysis of arabinan utilization systems illustrate that P. copri has evolved two distinct types of arabinan‐processing PULs (PULAra) and that the type‐II PULAra is significantly enriched in individuals consuming a vegan diet compared to other diets. In summary, this genetic toolbox will enable functional genetic studies for P. copri in future.
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Affiliation(s)
- Jing Li
- Department of Microbial Immune Regulation, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Eric J C Gálvez
- Department of Microbial Immune Regulation, Helmholtz Centre for Infection Research, Braunschweig, Germany.,Hannover Medical School, Hannover, Germany
| | - Lena Amend
- Department of Microbial Immune Regulation, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Éva Almási
- Department of Microbial Immune Regulation, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Aida Iljazovic
- Department of Microbial Immune Regulation, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Till R Lesker
- Department of Microbial Immune Regulation, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Agata A Bielecka
- Department of Microbial Immune Regulation, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Eva-Magdalena Schorr
- Department of Microbial Immune Regulation, Helmholtz Centre for Infection Research, Braunschweig, Germany
| | - Till Strowig
- Department of Microbial Immune Regulation, Helmholtz Centre for Infection Research, Braunschweig, Germany.,Hannover Medical School, Hannover, Germany.,Centre for Individualized Infection Medicine, Hannover, Germany
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20
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Kmezik C, Krska D, Mazurkewich S, Larsbrink J. Characterization of a novel multidomain CE15-GH8 enzyme encoded by a polysaccharide utilization locus in the human gut bacterium Bacteroides eggerthii. Sci Rep 2021; 11:17662. [PMID: 34480044 PMCID: PMC8417218 DOI: 10.1038/s41598-021-96659-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Accepted: 08/11/2021] [Indexed: 11/13/2022] Open
Abstract
Bacteroidetes are efficient degraders of complex carbohydrates, much thanks to their use of polysaccharide utilization loci (PULs). An integral part of PULs are highly specialized carbohydrate-active enzymes, sometimes composed of multiple linked domains with discrete functions—multicatalytic enzymes. We present the biochemical characterization of a multicatalytic enzyme from a large PUL encoded by the gut bacterium Bacteroides eggerthii. The enzyme, BeCE15A-Rex8A, has a rare and novel architecture, with an N-terminal carbohydrate esterase family 15 (CE15) domain and a C-terminal glycoside hydrolase family 8 (GH8) domain. The CE15 domain was identified as a glucuronoyl esterase (GE), though with relatively poor activity on GE model substrates, attributed to key amino acid substitutions in the active site compared to previously studied GEs. The GH8 domain was shown to be a reducing-end xylose-releasing exo-oligoxylanase (Rex), based on having activity on xylooligosaccharides but not on longer xylan chains. The full-length BeCE15A-Rex8A enzyme and the Rex domain were capable of boosting the activity of a commercially available GH11 xylanase on corn cob biomass. Our research adds to the understanding of multicatalytic enzyme architectures and showcases the potential of discovering novel and atypical carbohydrate-active enzymes from mining PULs.
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Affiliation(s)
- Cathleen Kmezik
- Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96, Gothenburg, Sweden
| | - Daniel Krska
- Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96, Gothenburg, Sweden
| | - Scott Mazurkewich
- Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96, Gothenburg, Sweden.,Wallenberg Wood Science Center, Chalmers University of Technology, 412 96, Gothenburg, Sweden
| | - Johan Larsbrink
- Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, 412 96, Gothenburg, Sweden. .,Wallenberg Wood Science Center, Chalmers University of Technology, 412 96, Gothenburg, Sweden.
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21
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Stevenson J, Ngo M, Brandt A, Weadge JT, Suits MDL. Analysis of Two SusE-Like Enzymes From Bacteroides thetaiotaomicron Reveals a Potential Degradative Capacity for This Protein Family. Front Microbiol 2021; 12:645765. [PMID: 34149636 PMCID: PMC8211771 DOI: 10.3389/fmicb.2021.645765] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2020] [Accepted: 04/06/2021] [Indexed: 01/04/2023] Open
Abstract
Bacteroides thetaiotaomicron is a major constituent of the human gut microbiome and recognized as a prolific degrader of diverse and complex carbohydrates. This capacity is due to the large number of glycan-depolymerization and acquisition systems that are encoded by gene clusters known as polysaccharide utilization loci (PUL), with the starch utilization system (Sus) serving as the established model. Sharing features with the Sus are Sus-like systems, that require the presence of a specific membrane transporter and surface lipoprotein to be classified as Sus-like. Sus-like import loci are extremely varied with respect to any additional protein components encoded, that would effectively modify the functionality of the degradative and import action of each locus. Herein we have identified eight Sus-like systems in B. thetaiotaomicron that share the feature of a homologous SusE-like factor encoded immediately downstream from the transporter/lipoprotein duo susC/D. Two SusE-like proteins from these systems, BT2857 and BT3158, were characterized by X-ray crystallography and BT2857 was further analyzed by small-angle X-ray scattering. The SusE-like proteins were found to be composed of a conserved three domain architecture: a partially disordered N-terminal domain that is predicted to be proximal to the membrane and structurally homologous to an FN3-like bundle, a middle β-sandwich domain, and a C-terminal domain homologous to family 32 carbohydrate-binding modules, that bind to galactose. Structural comparisons of SusE with SusE-like proteins suggested only a small structural divergence has occurred. However, functional analyses with BT2857 and BT3158 revealed that the SusE-like proteins exhibited galactosidase activity with para-nitrophenyl-β-D-galactopyranoside and α-(1,4)-lactose substrates, that has not been demonstrated for SusE proteins. Using a series of domain truncations of BT2857, the predominant β-D-galactosidase activity is suggested to be localized to the C-terminal DUF5126 domain that would be most distal from the outer membrane. The expanded functionality we have observed with these SusE-like proteins provides a plausible explanation of how Sus-like systems are adapted to target more diverse groups of carbohydrates, when compared to their Sus counterparts.
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Affiliation(s)
- James Stevenson
- Department of Chemistry and Biochemistry, Wilfrid Laurier University, Waterloo, ON, Canada
| | - Maria Ngo
- Department of Chemistry and Biochemistry, Wilfrid Laurier University, Waterloo, ON, Canada
| | - Alicia Brandt
- Groningen Biomolecular Sciences and Biotechnology Institute, Faculty of Science and Engineering, University of Groningen, Groningen, Netherlands
| | - Joel T Weadge
- Department of Biology, Wilfrid Laurier University, Waterloo, ON, Canada
| | - Michael D L Suits
- Department of Chemistry and Biochemistry, Wilfrid Laurier University, Waterloo, ON, Canada
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22
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Fernandez-Julia PJ, Munoz-Munoz J, van Sinderen D. A comprehensive review on the impact of β-glucan metabolism by Bacteroides and Bifidobacterium species as members of the gut microbiota. Int J Biol Macromol 2021; 181:877-889. [PMID: 33864864 DOI: 10.1016/j.ijbiomac.2021.04.069] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2020] [Revised: 04/01/2021] [Accepted: 04/10/2021] [Indexed: 12/16/2022]
Abstract
β-glucans are polysaccharides which can be obtained from different sources, and which have been described as potential prebiotics. The beneficial effects associated with β-glucan intake are that they reduce energy intake, lower cholesterol levels and support the immune system. Nevertheless, the mechanism(s) of action underpinning these health effects related to β-glucans are still unclear, and the precise impact of β-glucans on the gut microbiota has been subject to debate and revision. In this review, we summarize the most recent advances involving structurally different types of β-glucans as fermentable substrates for Bacteroidetes (mainly Bacteroides) and Bifidobacterium species as glycan degraders. Bacteroides is one of the most abundant bacterial components of the human gut microbiota, while bifidobacteria are widely employed as a probiotic ingredient. Both are generalist glycan degraders capable of using a wide range of substrates: Bacteroides spp. are specialized as primary degraders in the metabolism of complex carbohydrates, whereas Bifidobacterium spp. more commonly metabolize smaller glycans, in particular oligosaccharides, sometimes through syntrophic interactions with Bacteroides spp., in which they act as secondary degraders.
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Affiliation(s)
- Pedro J Fernandez-Julia
- Department of Applied Sciences, Northumbria University, Newcastle Upon Tyne NE1 8ST, Tyne & Wear, England, United Kingdom
| | - Jose Munoz-Munoz
- Department of Applied Sciences, Northumbria University, Newcastle Upon Tyne NE1 8ST, Tyne & Wear, England, United Kingdom.
| | - Douwe van Sinderen
- School of Microbiology & APC Microbiome Ireland, University College Cork, Ireland University College Cork, Cork, Ireland.
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23
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Pollet RM, Martin LM, Koropatkin NM. TonB-dependent transporters in the Bacteroidetes: Unique domain structures and potential functions. Mol Microbiol 2021; 115:490-501. [PMID: 33448497 DOI: 10.1111/mmi.14683] [Citation(s) in RCA: 36] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/23/2020] [Revised: 01/10/2021] [Accepted: 01/11/2021] [Indexed: 12/26/2022]
Abstract
The human gut microbiota endows the host with a wealth of metabolic functions central to health, one of which is the degradation and fermentation of complex carbohydrates. The Bacteroidetes are one of the dominant bacterial phyla of this community and possess an expanded capacity for glycan utilization. This is mediated via the coordinated expression of discrete polysaccharide utilization loci (PUL) that invariantly encode a TonB-dependent transporter (SusC) that works with a glycan-capturing lipoprotein (SusD). More broadly within Gram-negative bacteria, TonB-dependent transporters (TBDTs) are deployed for the uptake of not only sugars, but also more often for essential nutrients such as iron and vitamins. Here, we provide a comprehensive look at the repertoire of TBDTs found in the model gut symbiont Bacteroides thetaiotaomicron and the range of predicted functional domains associated with these transporters and SusD proteins for the uptake of both glycans and other nutrients. This atlas of the B. thetaiotaomicron TBDTs reveals that there are at least three distinct subtypes of these transporters encoded within its genome that are presumably regulated in different ways to tune nutrient uptake.
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Affiliation(s)
| | - Lauryn M Martin
- Department of Biology, Alcorn State University, Alcorn, MS, USA
| | - Nicole M Koropatkin
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, MI, USA
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24
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Degradation of complex arabinoxylans by human colonic Bacteroidetes. Nat Commun 2021; 12:459. [PMID: 33469030 PMCID: PMC7815789 DOI: 10.1038/s41467-020-20737-5] [Citation(s) in RCA: 75] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2019] [Accepted: 12/09/2020] [Indexed: 01/07/2023] Open
Abstract
Some Bacteroidetes and other human colonic bacteria can degrade arabinoxylans, common polysaccharides found in dietary fiber. Previous work has identified gene clusters (polysaccharide-utilization loci, PULs) for degradation of simple arabinoxylans. However, the degradation of complex arabinoxylans (containing side chains such as ferulic acid, a phenolic compound) is poorly understood. Here, we identify a PUL that encodes multiple esterases for degradation of complex arabinoxylans in Bacteroides species. The PUL is specifically upregulated in the presence of complex arabinoxylans. We characterize some of the esterases biochemically and structurally, and show that they release ferulic acid from complex arabinoxylans. Growth of four different colonic Bacteroidetes members, including Bacteroides intestinalis, on complex arabinoxylans results in accumulation of ferulic acid, a compound known to have antioxidative and immunomodulatory properties.
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25
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Non-oral Prevotella stepping into the spotlight. Anaerobe 2021; 68:102321. [PMID: 33482304 DOI: 10.1016/j.anaerobe.2021.102321] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2020] [Revised: 01/12/2021] [Accepted: 01/14/2021] [Indexed: 02/07/2023]
Abstract
Species now affiliated to genus Prevotella have been known for decades as an integral part of human oral cavity microbiota. They were frequently isolated from patients with periodontitis or from dental root canals but also from healthy subjects. With the exception of Prevotella intermedia, they were considered opportunistic pathogens, as they were isolated also from various bacterial abscesses from the head, neck, breast, skin and various other body sites. Consequently, Prevotella were not in the focus of research activities. On the other hand, the four species found in the rumen never caused any disease and seemed early on to be numerous and important part of the rumen ecosystem indicating this genus harbored bacteria with enormously diverse habitats and lifestyles. The purpose of this review is to illustrate the main research themes performed in Prevotella on a path from less noted oral bacteria and from hard to cultivate and study rumen organisms to important mutualistic bacteria in guts of various mammals warranting major research efforts.
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26
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Gray DA, White JBR, Oluwole AO, Rath P, Glenwright AJ, Mazur A, Zahn M, Baslé A, Morland C, Evans SL, Cartmell A, Robinson CV, Hiller S, Ranson NA, Bolam DN, van den Berg B. Insights into SusCD-mediated glycan import by a prominent gut symbiont. Nat Commun 2021; 12:44. [PMID: 33398001 PMCID: PMC7782687 DOI: 10.1038/s41467-020-20285-y] [Citation(s) in RCA: 42] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2020] [Accepted: 11/19/2020] [Indexed: 01/29/2023] Open
Abstract
In Bacteroidetes, one of the dominant phyla of the mammalian gut, active uptake of large nutrients across the outer membrane is mediated by SusCD protein complexes via a "pedal bin" transport mechanism. However, many features of SusCD function in glycan uptake remain unclear, including ligand binding, the role of the SusD lid and the size limit for substrate transport. Here we characterise the β2,6 fructo-oligosaccharide (FOS) importing SusCD from Bacteroides thetaiotaomicron (Bt1762-Bt1763) to shed light on SusCD function. Co-crystal structures reveal residues involved in glycan recognition and suggest that the large binding cavity can accommodate several substrate molecules, each up to ~2.5 kDa in size, a finding supported by native mass spectrometry and isothermal titration calorimetry. Mutational studies in vivo provide functional insights into the key structural features of the SusCD apparatus and cryo-EM of the intact dimeric SusCD complex reveals several distinct states of the transporter, directly visualising the dynamics of the pedal bin transport mechanism.
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Affiliation(s)
- Declan A Gray
- Biosciences Institute, The Medical School, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Joshua B R White
- Astbury Centre for Structural Molecular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
| | - Abraham O Oluwole
- Physical and Theoretical Chemistry Laboratory, University of Oxford, Oxford, OX1 3QZ, UK
| | | | - Amy J Glenwright
- Biosciences Institute, The Medical School, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Adam Mazur
- Biozentrum, University of Basel, Basel, Switzerland
| | - Michael Zahn
- Biozentrum, University of Basel, Basel, Switzerland
| | - Arnaud Baslé
- Biosciences Institute, The Medical School, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Carl Morland
- Biosciences Institute, The Medical School, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK
| | - Sasha L Evans
- Astbury Centre for Structural Molecular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
| | - Alan Cartmell
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Liverpool, L69 7ZB, UK
| | - Carol V Robinson
- Physical and Theoretical Chemistry Laboratory, University of Oxford, Oxford, OX1 3QZ, UK
| | | | - Neil A Ranson
- Astbury Centre for Structural Molecular Biology, Faculty of Biological Sciences, University of Leeds, Leeds, LS2 9JT, UK
| | - David N Bolam
- Biosciences Institute, The Medical School, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK.
| | - Bert van den Berg
- Biosciences Institute, The Medical School, Newcastle University, Newcastle upon Tyne, NE2 4HH, UK.
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27
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Abstract
Resistant starch, microbiome, and precision modulation. Mounting evidence has positioned the gut microbiome as a nexus of health. Modulating its phylogenetic composition and function has become an attractive therapeutic prospect. Resistant starches (granular amylase-resistant α-glycans) are available as physicochemically and morphologically distinguishable products. Attempts to leverage resistant starch as microbiome-modifying interventions in clinical studies have yielded remarkable inter-individual variation. Consequently, their utility as a potential therapy likely depends predominantly on the selected resistant starch and the subject's baseline microbiome. The purpose of this review is to detail i) the heterogeneity of resistant starches, ii) how resistant starch is sequentially degraded and fermented by specialized gut microbes, and iii) how resistant starch interventions yield variable effects on the gut microbiome.
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Affiliation(s)
- Peter A. Dobranowski
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada
- Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, Ontario, Canada
| | - Alain Stintzi
- Department of Biochemistry, Microbiology and Immunology, University of Ottawa, Ottawa, Ontario, Canada
- Ottawa Institute of Systems Biology, University of Ottawa, Ottawa, Ontario, Canada
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28
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Briggs JA, Grondin JM, Brumer H. Communal living: glycan utilization by the human gut microbiota. Environ Microbiol 2020; 23:15-35. [PMID: 33185970 DOI: 10.1111/1462-2920.15317] [Citation(s) in RCA: 35] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Revised: 11/06/2020] [Accepted: 11/09/2020] [Indexed: 12/15/2022]
Abstract
Our lower gastrointestinal tract plays host to a vast consortium of microbes, known as the human gut microbiota (HGM). The HGM thrives on a complex and diverse range of glycan structures from both dietary and host sources, the breakdown of which requires the concerted action of cohorts of carbohydrate-active enzymes (CAZymes), carbohydrate-binding proteins, and transporters. The glycan utilization profile of individual taxa, whether 'specialist' or 'generalist', is dictated by the number and functional diversity of these glycan utilization systems. Furthermore, taxa in the HGM may either compete or cooperate in glycan deconstruction, thereby creating a complex ecological web spanning diverse nutrient niches. As a result, our diet plays a central role in shaping the composition of the HGM. This review presents an overview of our current understanding of glycan utilization by the HGM on three levels: (i) molecular mechanisms of individual glycan deconstruction and uptake by key bacteria, (ii) glycan-mediated microbial interactions, and (iii) community-scale effects of dietary changes. Despite significant recent advancements, there remains much to be discovered regarding complex glycan metabolism in the HGM and its potential to affect positive health outcomes.
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Affiliation(s)
- Jonathon A Briggs
- Michael Smith Laboratories, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Julie M Grondin
- Michael Smith Laboratories, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Harry Brumer
- Michael Smith Laboratories, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada.,Department of Chemistry, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada.,Department of Biochemistry and Molecular Biology, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada.,Department of Botany, University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
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29
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Singh RP, Bhaiyya R, Khandare K, Tingirikari JMR. Macroalgal dietary glycans: potential source for human gut bacteria and enhancing immune system for better health. Crit Rev Food Sci Nutr 2020; 62:1674-1695. [PMID: 33190530 DOI: 10.1080/10408398.2020.1845605] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Macroalgae are the diverse group of photosynthetic algae found at the intertidal regions of oceans. Recent advances suggest that macroalgal derived glycans have tremendous potential to maintain gut microbiome and immune system. The human gut bacteria harbor unique arsenals for utilizing a variety of macroalgal glycans, and produce a variety of oligosaccharides in vivo. Those oligosaccharides interact with immune cell receptors, and also are available for microbial fermentation, thus play magnificent roles in balancing the gut homeostasis. However, this area of research is still in infancy condition in term to understand their molecular interactions. For wooing this area, we urge to emphasize more studies on mechanistic level sympathetic of depolymerizing marine dietary glycans by gut bacteria and elucidating molecular aspect of glycans to cell receptors interactions. This will invent new nutraceutical strategies to purposefully manipulate the microbial composition to improve health. Therefore, review focuses on the recent development of mechanistic understanding of human gut bacterial communities for utilizing macroalgal derived glycans. Recent trends of application of glycans in modulating immune system at mechanistic level and their available evidences are discussed.
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Affiliation(s)
- Ravindra Pal Singh
- Food and Nutritional Biotechnology Division, National Agri-Food Biotechnology Institute (NABI), Punjab, India
| | - Raja Bhaiyya
- Food and Nutritional Biotechnology Division, National Agri-Food Biotechnology Institute (NABI), Punjab, India
| | - Kiran Khandare
- Food and Nutritional Biotechnology Division, National Agri-Food Biotechnology Institute (NABI), Punjab, India
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30
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Pierce JV, Fellows JD, Anderson DE, Bernstein HD. A clostripain-like protease plays a major role in generating the secretome of enterotoxigenic Bacteroides fragilis. Mol Microbiol 2020; 115:290-304. [PMID: 32996200 DOI: 10.1111/mmi.14616] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2020] [Revised: 09/21/2020] [Accepted: 09/23/2020] [Indexed: 11/27/2022]
Abstract
Bacteroides fragilis toxin (BFT) is a protein secreted by enterotoxigenic (ETBF) strains of B. fragilis. BFT is synthesized as a proprotein (proBFT) that is predicted to be a lipoprotein and that is cleaved into two discrete fragments by a clostripain-like protease called fragipain (Fpn). In this study, we obtained evidence that Fpn cleaves proBFT following its transport across the outer membrane. Remarkably, we also found that the disruption of the fpn gene led to a strong reduction in the level of >100 other proteins, many of which are predicted to be lipoproteins, in the culture medium of an ETBF strain. Experiments performed with purified Fpn provided direct evidence that the protease releases at least some of these proteins from the cell surface. The observation that wild-type cells outcompeted an fpn- strain in co-cultivation assays also supported the notion that Fpn plays an important role in cell physiology and is not simply dedicated to toxin biogenesis. Finally, we found that purified Fpn altered the adhesive properties of HT29 intestinal epithelial cells. Our results suggest that Fpn is a broad-spectrum protease that not only catalyzes the protein secretion on a wide scale but that also potentially cleaves host cell proteins during colonization.
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Affiliation(s)
- Jessica V Pierce
- Genetics and Biochemistry Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Justin D Fellows
- Genetics and Biochemistry Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
| | - D Eric Anderson
- Advanced Mass Spectrometry Facility, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
| | - Harris D Bernstein
- Genetics and Biochemistry Branch, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD, USA
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Trzilova D, Tamayo R. Site-Specific Recombination - How Simple DNA Inversions Produce Complex Phenotypic Heterogeneity in Bacterial Populations. Trends Genet 2020; 37:59-72. [PMID: 33008627 DOI: 10.1016/j.tig.2020.09.004] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Revised: 08/26/2020] [Accepted: 09/01/2020] [Indexed: 02/07/2023]
Abstract
Many bacterial species generate phenotypically heterogeneous subpopulations as a strategy for ensuring the survival of the population as a whole - an environmental stress that eradicates one subpopulation may leave other phenotypic groups unharmed, allowing the lineage to continue. Phase variation, a process that functions as an ON/OFF switch for gene expression, is one way that bacteria achieve phenotypic heterogeneity. Phase variation occurs stochastically and reversibly, and in the presence of a selective pressure the advantageous phenotype(s) predominates in the population. Phase variation can occur through multiple genetic and epigenetic mechanisms. This review focuses on conservative site-specific recombination that generates reversible DNA inversions as a genetic mechanism mediating phase variation. Recent studies have sparked a renewed interest in phase variation mediated through DNA inversion, revealing a high level of complexity beyond simple ON/OFF switching, including unusual modes of gene regulation, and highlighting an underappreciation of the use of these mechanisms by bacteria.
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Affiliation(s)
- Dominika Trzilova
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, USA
| | - Rita Tamayo
- Department of Microbiology and Immunology, University of North Carolina at Chapel Hill School of Medicine, Chapel Hill, NC, USA.
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32
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Liou CS, Sirk SJ, Diaz CAC, Klein AP, Fischer CR, Higginbottom SK, Erez A, Donia MS, Sonnenburg JL, Sattely ES. A Metabolic Pathway for Activation of Dietary Glucosinolates by a Human Gut Symbiont. Cell 2020; 180:717-728.e19. [PMID: 32084341 DOI: 10.1016/j.cell.2020.01.023] [Citation(s) in RCA: 80] [Impact Index Per Article: 20.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2019] [Revised: 11/04/2019] [Accepted: 01/15/2020] [Indexed: 02/07/2023]
Abstract
Consumption of glucosinolates, pro-drug-like metabolites abundant in Brassica vegetables, has been associated with decreased risk of certain cancers. Gut microbiota have the ability to metabolize glucosinolates, generating chemopreventive isothiocyanates. Here, we identify a genetic and biochemical basis for activation of glucosinolates to isothiocyanates by Bacteroides thetaiotaomicron, a prominent gut commensal species. Using a genome-wide transposon insertion screen, we identified an operon required for glucosinolate metabolism in B. thetaiotaomicron. Expression of BT2159-BT2156 in a non-metabolizing relative, Bacteroides fragilis, resulted in gain of glucosinolate metabolism. We show that isothiocyanate formation requires the action of BT2158 and either BT2156 or BT2157 in vitro. Monocolonization of mice with mutant BtΔ2157 showed reduced isothiocyanate production in the gastrointestinal tract. These data provide insight into the mechanisms by which a common gut bacterium processes an important dietary nutrient.
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Affiliation(s)
- Catherine S Liou
- Department of Chemical Engineering, Stanford University, Stanford, CA 94305, USA
| | - Shannon J Sirk
- Department of Chemical Engineering, Stanford University, Stanford, CA 94305, USA
| | - Camil A C Diaz
- Department of Chemical Engineering, Stanford University, Stanford, CA 94305, USA
| | - Andrew P Klein
- Department of Chemical Engineering, Stanford University, Stanford, CA 94305, USA
| | - Curt R Fischer
- Chemistry, Engineering, and Medicine for Human Health, Stanford University, Stanford, CA 94305, USA
| | - Steven K Higginbottom
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Amir Erez
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
| | - Mohamed S Donia
- Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA
| | - Justin L Sonnenburg
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Elizabeth S Sattely
- Department of Chemical Engineering, Stanford University, Stanford, CA 94305, USA; Howard Hughes Medical Institute, Stanford University, Stanford, CA 94305, USA.
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33
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Gavriilidou A, Gutleben J, Versluis D, Forgiarini F, van Passel MWJ, Ingham CJ, Smidt H, Sipkema D. Comparative genomic analysis of Flavobacteriaceae: insights into carbohydrate metabolism, gliding motility and secondary metabolite biosynthesis. BMC Genomics 2020; 21:569. [PMID: 32819293 PMCID: PMC7440613 DOI: 10.1186/s12864-020-06971-7] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2020] [Accepted: 08/05/2020] [Indexed: 01/24/2023] Open
Abstract
BACKGROUND Members of the bacterial family Flavobacteriaceae are widely distributed in the marine environment and often found associated with algae, fish, detritus or marine invertebrates. Yet, little is known about the characteristics that drive their ubiquity in diverse ecological niches. Here, we provide an overview of functional traits common to taxonomically diverse members of the family Flavobacteriaceae from different environmental sources, with a focus on the Marine clade. We include seven newly sequenced marine sponge-derived strains that were also tested for gliding motility and antimicrobial activity. RESULTS Comparative genomics revealed that genome similarities appeared to be correlated to 16S rRNA gene- and genome-based phylogeny, while differences were mostly associated with nutrient acquisition, such as carbohydrate metabolism and gliding motility. The high frequency and diversity of genes encoding polymer-degrading enzymes, often arranged in polysaccharide utilization loci (PULs), support the capacity of marine Flavobacteriaceae to utilize diverse carbon sources. Homologs of gliding proteins were widespread among all studied Flavobacteriaceae in contrast to members of other phyla, highlighting the particular presence of this feature within the Bacteroidetes. Notably, not all bacteria predicted to glide formed spreading colonies. Genome mining uncovered a diverse secondary metabolite biosynthesis arsenal of Flavobacteriaceae with high prevalence of gene clusters encoding pathways for the production of antimicrobial, antioxidant and cytotoxic compounds. Antimicrobial activity tests showed, however, that the phenotype differed from the genome-derived predictions for the seven tested strains. CONCLUSIONS Our study elucidates the functional repertoire of marine Flavobacteriaceae and highlights the need to combine genomic and experimental data while using the appropriate stimuli to unlock their uncharted metabolic potential.
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Affiliation(s)
- Asimenia Gavriilidou
- Laboratory of Microbiology, Wageningen University & Research, Stippeneng 4, 6708 WE Wageningen, The Netherlands
| | - Johanna Gutleben
- Laboratory of Microbiology, Wageningen University & Research, Stippeneng 4, 6708 WE Wageningen, The Netherlands
| | - Dennis Versluis
- Laboratory of Microbiology, Wageningen University & Research, Stippeneng 4, 6708 WE Wageningen, The Netherlands
| | - Francesca Forgiarini
- Laboratory of Microbiology, Wageningen University & Research, Stippeneng 4, 6708 WE Wageningen, The Netherlands
| | - Mark W. J. van Passel
- Laboratory of Microbiology, Wageningen University & Research, Stippeneng 4, 6708 WE Wageningen, The Netherlands
- Present address: Ministry of Health, Welfare and Sport, Parnassusplein 5, 2511 VX, The Hague, The Netherlands
| | | | - Hauke Smidt
- Laboratory of Microbiology, Wageningen University & Research, Stippeneng 4, 6708 WE Wageningen, The Netherlands
| | - Detmer Sipkema
- Laboratory of Microbiology, Wageningen University & Research, Stippeneng 4, 6708 WE Wageningen, The Netherlands
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Wang C, Zhao J, Zhang H, Lee YK, Zhai Q, Chen W. Roles of intestinal bacteroides in human health and diseases. Crit Rev Food Sci Nutr 2020; 61:3518-3536. [PMID: 32757948 DOI: 10.1080/10408398.2020.1802695] [Citation(s) in RCA: 53] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Bacteroides, an abundant genus in the intestines of mammals, has been recently considered as the next generation probiotics (NGP) candidate due to its potential role in promoting host health. However, the role of Bacteroides in the development of intestinal dysfunctions such as diarrhea, inflammatory bowel disease, and colorectal cancer should not be overlooked. In the present study, we focused on nine most widely occurred and abundant Bacteroides species and discussed their roles in host immunity, glucose and lipid metabolism and the prevention or induction of diseases. Besides, we also discussed the current methods used in the safety evaluation of Bacteroides species and key opinions about the concerns of these strains for the future use.
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Affiliation(s)
- Chen Wang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, P.R. China.,School of Food Science and Technology, Jiangnan University, Wuxi, China
| | - Jianxin Zhao
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, P.R. China.,School of Food Science and Technology, Jiangnan University, Wuxi, China
| | - Hao Zhang
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, P.R. China.,School of Food Science and Technology, Jiangnan University, Wuxi, China.,National Engineering Research Center for Functional Food, Jiangnan University, Wuxi, China.,Research Institute, Wuxi Translational Medicine Research Center and Jiangsu Translational Medicine, Wuxi, China.,(Yangzhou) Institute of Food Biotechnology, Jiangnan University, Yangzhou, China
| | - Yuan-Kun Lee
- Department of Microbiology & Immunology, National University of Singapore, Singapore, Singapore
| | - Qixiao Zhai
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, P.R. China.,School of Food Science and Technology, Jiangnan University, Wuxi, China.,International Joint Research Laboratory for Probiotics, Jiangnan University, Wuxi, China
| | - Wei Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, P.R. China.,School of Food Science and Technology, Jiangnan University, Wuxi, China.,National Engineering Research Center for Functional Food, Jiangnan University, Wuxi, China.,Beijing Innovation Centre of Food Nutrition and Human Health, Beijing Technology and Business University (BTBU), Beijing, P.R. China
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35
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Zlitni S, Bishara A, Moss EL, Tkachenko E, Kang JB, Culver RN, Andermann TM, Weng Z, Wood C, Handy C, Ji HP, Batzoglou S, Bhatt AS. Strain-resolved microbiome sequencing reveals mobile elements that drive bacterial competition on a clinical timescale. Genome Med 2020; 12:50. [PMID: 32471482 PMCID: PMC7260799 DOI: 10.1186/s13073-020-00747-0] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2019] [Accepted: 05/11/2020] [Indexed: 02/08/2023] Open
Abstract
BACKGROUND Populations of closely related microbial strains can be simultaneously present in bacterial communities such as the human gut microbiome. We recently developed a de novo genome assembly approach that uses read cloud sequencing to provide more complete microbial genome drafts, enabling precise differentiation and tracking of strain-level dynamics across metagenomic samples. In this case study, we present a proof-of-concept using read cloud sequencing to describe bacterial strain diversity in the gut microbiome of one hematopoietic cell transplantation patient over a 2-month time course and highlight temporal strain variation of gut microbes during therapy. The treatment was accompanied by diet changes and administration of multiple immunosuppressants and antimicrobials. METHODS We conducted short-read and read cloud metagenomic sequencing of DNA extracted from four longitudinal stool samples collected during the course of treatment of one hematopoietic cell transplantation (HCT) patient. After applying read cloud metagenomic assembly to discover strain-level sequence variants in these complex microbiome samples, we performed metatranscriptomic analysis to investigate differential expression of antibiotic resistance genes. Finally, we validated predictions from the genomic and metatranscriptomic findings through in vitro antibiotic susceptibility testing and whole genome sequencing of isolates derived from the patient stool samples. RESULTS During the 56-day longitudinal time course that was studied, the patient's microbiome was profoundly disrupted and eventually dominated by Bacteroides caccae. Comparative analysis of B. caccae genomes obtained using read cloud sequencing together with metagenomic RNA sequencing allowed us to identify differences in substrain populations over time. Based on this, we predicted that particular mobile element integrations likely resulted in increased antibiotic resistance, which we further supported using in vitro antibiotic susceptibility testing. CONCLUSIONS We find read cloud assembly to be useful in identifying key structural genomic strain variants within a metagenomic sample. These strains have fluctuating relative abundance over relatively short time periods in human microbiomes. We also find specific structural genomic variations that are associated with increased antibiotic resistance over the course of clinical treatment.
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Affiliation(s)
- Soumaya Zlitni
- Departments of Genetics, Stanford University, Stanford, CA USA
- Department of Medicine, Division of Hematology, Stanford University, 269 Campus Drive, MC5156, Stanford, CA 94305 USA
| | - Alex Bishara
- Departments of Genetics, Stanford University, Stanford, CA USA
- Department of Computer Science, Stanford University, Stanford, CA USA
| | - Eli L. Moss
- Departments of Genetics, Stanford University, Stanford, CA USA
- Department of Medicine, Division of Hematology, Stanford University, 269 Campus Drive, MC5156, Stanford, CA 94305 USA
| | - Ekaterina Tkachenko
- Departments of Genetics, Stanford University, Stanford, CA USA
- Department of Medicine, Division of Hematology, Stanford University, 269 Campus Drive, MC5156, Stanford, CA 94305 USA
| | | | | | - Tessa M. Andermann
- Department of Medicine, Division of Infectious Diseases, University of North Carolina, Chapel Hill, USA
| | - Ziming Weng
- Department of Pathology, Stanford University School of Medicine, Stanford, CA USA
| | - Christina Wood
- Division of Oncology, Department of Medicine, Stanford University, Stanford, CA USA
| | - Christine Handy
- Division of Oncology, Department of Medicine, Stanford University, Stanford, CA USA
| | - Hanlee P. Ji
- Division of Oncology, Department of Medicine, Stanford University, Stanford, CA USA
| | - Serafim Batzoglou
- Department of Computer Science, Stanford University, Stanford, CA USA
| | - Ami S. Bhatt
- Departments of Genetics, Stanford University, Stanford, CA USA
- Department of Medicine, Division of Hematology, Stanford University, 269 Campus Drive, MC5156, Stanford, CA 94305 USA
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36
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Cerqueira FM, Photenhauer AL, Pollet RM, Brown HA, Koropatkin NM. Starch Digestion by Gut Bacteria: Crowdsourcing for Carbs. Trends Microbiol 2020; 28:95-108. [DOI: 10.1016/j.tim.2019.09.004] [Citation(s) in RCA: 54] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2019] [Revised: 08/29/2019] [Accepted: 09/09/2019] [Indexed: 12/12/2022]
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37
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Zayulina KS, Kochetkova TV, Piunova UE, Ziganshin RH, Podosokorskaya OA, Kublanov IV. Novel Hyperthermophilic Crenarchaeon Thermofilum adornatum sp. nov. Uses GH1, GH3, and Two Novel Glycosidases for Cellulose Hydrolysis. Front Microbiol 2020; 10:2972. [PMID: 31998263 PMCID: PMC6965361 DOI: 10.3389/fmicb.2019.02972] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2019] [Accepted: 12/10/2019] [Indexed: 01/16/2023] Open
Abstract
A novel hyperthermophilic, anaerobic filamentous archaeon, Thermofilum adornatum strain 1910bT, is capable of growing with cellulose as its sole carbon and energy source. This strain was isolated from a terrestrial hot spring in Kamchatka, Russia. The isolate 1910bT grew optimally at a temperature of 80°C and a pH of 5.5-6.0, producing cell-bound inducible cellulases. During genome analysis, genes, encoding various glycosidases (GHs) involved in oligo- and polysaccharide hydrolysis and genes for the fermentation of sugars were identified. No homologs of currently known cellulase families were found among the GHs encoded by the 1910bT genome, suggesting that novel proteins are involved. To figure this out, a proteomic analysis of cells grown on cellulose or pyruvate (as a control) was performed. Both in-depth genomic and proteomic analyses revealed four proteins (Cel25, Cel30, Cel40, and Cel45) that were the most likely to be involved in the cellulose hydrolysis in this archaeon. Two of these proteins (Cel30 and Cel45) were hypothetical according to genome analysis, while the other two (Cel25 and Cel40) have GH3 and GH1 domains, respectively. The respective genes were heterologously expressed in Escherichia coli BL21 (DE3), and enzymatic activities of recombinant proteins were measured with carboxymethyl cellulose (CMC), Avicel and cellobiose as substrates. It was revealed that the Cel30 and Cel25 proteins were likely exoglucanases with side beta-glucosidase and endoglucanase activities, that Cel40 was a multifunctional glucanase capable of hydrolyzing beta-1,4-glucosides of various lengths, and that Cel45 was an endoglucanase with side exoglucanase activity. Taking into account that the cellulolytic activity of T. adornatum 1910bT surface protein fractions was inducible, that recombinant Cel25 and Cel30 were much less active than Cel40 and Cel45, and that their gene expressions were (almost) non-induced by CMC, we suggest that Cel40 and Cel45 play a major role in the degradation of cellulose, while Cel25 and Cel30 act only as accessory enzymes.
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Affiliation(s)
- Kseniya S. Zayulina
- Research Center of Biotechnology, Winogradsky Institute of Microbiology, Russian Academy of Sciences, Moscow, Russia
| | - Tatiana V. Kochetkova
- Research Center of Biotechnology, Winogradsky Institute of Microbiology, Russian Academy of Sciences, Moscow, Russia
| | - Ulyana E. Piunova
- Research Center of Biotechnology, Winogradsky Institute of Microbiology, Russian Academy of Sciences, Moscow, Russia
- Faculty of Bioengineering and Bioinformatics, Lomonosov Moscow State University, Moscow, Russia
| | - Rustam H. Ziganshin
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, Moscow, Russia
| | - Olga A. Podosokorskaya
- Research Center of Biotechnology, Winogradsky Institute of Microbiology, Russian Academy of Sciences, Moscow, Russia
| | - Ilya V. Kublanov
- Research Center of Biotechnology, Winogradsky Institute of Microbiology, Russian Academy of Sciences, Moscow, Russia
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38
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Larsbrink J, McKee LS. Bacteroidetes bacteria in the soil: Glycan acquisition, enzyme secretion, and gliding motility. ADVANCES IN APPLIED MICROBIOLOGY 2020; 110:63-98. [PMID: 32386606 DOI: 10.1016/bs.aambs.2019.11.001] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
The secretion of extracellular enzymes by soil microbes is rate-limiting in the recycling of biomass. Fungi and bacteria compete and collaborate for nutrients in the soil, with wide ranging ecological impacts. Within soil microbiota, the Bacteroidetes tend to be a dominant phylum, just like in human and animal intestines. The Bacteroidetes thrive because of their ability to secrete diverse arrays of carbohydrate-active enzymes (CAZymes) that target the highly varied glycans in the soil. Bacteroidetes use an energy-saving system of genomic organization, whereby most of their CAZymes are grouped into Polysaccharide Utilization Loci (PULs). These loci enable high level production of specific CAZymes only when their substrate glycans are abundant in the local environment. This gives the Bacteroidetes a clear advantage over other species in the competitive soil environment, further enhanced by the phylum-specific Type IX Secretion System (T9SS). The T9SS is highly effective at secreting CAZymes and/or tethering them to the cell surface, and is tightly coupled to the ability to rapidly glide over solid surfaces, a connection that promotes an active hunt for nutrition. Although the soil Bacteroidetes are less well studied than human gut symbionts, research is uncovering important biochemical and physiological phenomena. In this review, we summarize the state of the art on research into the CAZymes secreted by soil Bacteroidetes in the contexts of microbial soil ecology and the discovery of novel CAZymes for use in industrial biotechnology. We hope that this review will stimulate further investigations into the somewhat neglected enzymology of non-gut Bacteroidetes.
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Affiliation(s)
- Johan Larsbrink
- Wallenberg Wood Science Center, Gothenburg and Stockholm, Sweden; Division of Industrial Biotechnology, Department of Biology and Biological Engineering, Chalmers University of Technology, Gothenburg, Sweden
| | - Lauren Sara McKee
- Wallenberg Wood Science Center, Gothenburg and Stockholm, Sweden; Division of Glycoscience, Department of Chemistry, KTH Royal Institute of Technology, AlbaNova University Centre, Stockholm, Sweden.
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39
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Cabral DJ, Penumutchu S, Reinhart EM, Zhang C, Korry BJ, Wurster JI, Nilson R, Guang A, Sano WH, Rowan-Nash AD, Li H, Belenky P. Microbial Metabolism Modulates Antibiotic Susceptibility within the Murine Gut Microbiome. Cell Metab 2019; 30:800-823.e7. [PMID: 31523007 PMCID: PMC6948150 DOI: 10.1016/j.cmet.2019.08.020] [Citation(s) in RCA: 56] [Impact Index Per Article: 11.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 01/31/2019] [Revised: 06/24/2019] [Accepted: 08/20/2019] [Indexed: 12/22/2022]
Abstract
Although antibiotics disturb the structure of the gut microbiota, factors that modulate these perturbations are poorly understood. Bacterial metabolism is an important regulator of susceptibility in vitro and likely plays a large role within the host. We applied a metagenomic and metatranscriptomic approach to link antibiotic-induced taxonomic and transcriptional responses within the murine microbiome. We found that antibiotics significantly alter the expression of key metabolic pathways at the whole-community and single-species levels. Notably, Bacteroides thetaiotaomicron, which blooms in response to amoxicillin, upregulated polysaccharide utilization. In vitro, we found that the sensitivity of this bacterium to amoxicillin was elevated by glucose and reduced by polysaccharides. Accordingly, we observed that dietary composition affected the abundance and expansion of B. thetaiotaomicron, as well as the extent of microbiome disruption with amoxicillin. Our work indicates that the metabolic environment of the microbiome plays a role in the response of this community to antibiotics.
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Affiliation(s)
- Damien J Cabral
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI 02906, USA
| | - Swathi Penumutchu
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI 02906, USA
| | - Elizabeth M Reinhart
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI 02906, USA
| | - Cheng Zhang
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN 55904, USA
| | - Benjamin J Korry
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI 02906, USA
| | - Jenna I Wurster
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI 02906, USA
| | - Rachael Nilson
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI 02906, USA
| | - August Guang
- Center for Computation & Visualization, Brown University, Brown University, Providence, RI 02906, USA; Center for Computational Biology of Human Disease, Brown University, Providence, RI 02906, USA
| | - William H Sano
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI 02906, USA
| | - Aislinn D Rowan-Nash
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI 02906, USA
| | - Hu Li
- Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN 55904, USA
| | - Peter Belenky
- Department of Molecular Microbiology and Immunology, Brown University, Providence, RI 02906, USA.
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40
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Bertucci M, Calusinska M, Goux X, Rouland-Lefèvre C, Untereiner B, Ferrer P, Gerin PA, Delfosse P. Carbohydrate Hydrolytic Potential and Redundancy of an Anaerobic Digestion Microbiome Exposed to Acidosis, as Uncovered by Metagenomics. Appl Environ Microbiol 2019; 85:e00895-19. [PMID: 31152018 PMCID: PMC6643232 DOI: 10.1128/aem.00895-19] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2019] [Accepted: 05/26/2019] [Indexed: 12/22/2022] Open
Abstract
Increased hydrolysis of easily digestible biomass may lead to acidosis of anaerobic reactors and decreased methane production. Previously, it was shown that the structure of microbial communities changed during acidosis; however, once the conditions are back to optimal, biogas (initially CO2) production quickly restarts. This suggests the retention of the community functional redundancy during the process failure. In this study, with the use of metagenomics and downstream bioinformatics analyses, we characterize the carbohydrate hydrolytic potential of the microbial community, with a special focus on acidosis. To that purpose, carbohydrate-active enzymes were identified, and to further link the community hydrolytic potential with key microbes, bacterial genomes were reconstructed. In addition, we characterized biochemically the specificity and activity of selected enzymes, thus verifying the accuracy of the in silico predictions. The results confirm the retention of the community hydrolytic potential during acidosis and indicate Bacteroidetes to be largely involved in biomass degradation. Bacteroidetes showed higher diversity and genomic content of carbohydrate hydrolytic enzymes that might favor the dominance of this phylum over other bacteria in some anaerobic reactors. The combination of bioinformatic analyses and activity tests enabled us to propose a model of acetylated glucomannan degradation by BacteroidetesIMPORTANCE The enzymatic hydrolysis of lignocellulosic biomass is mainly driven by the action of carbohydrate-active enzymes. By characterizing the gene profiles at the different stages of the anaerobic digestion experiment, we showed that the microbiome retains its hydrolytic functional redundancy even during severe acidosis, despite significant changes in taxonomic composition. By analyzing reconstructed bacterial genomes, we demonstrate that Bacteroidetes hydrolytic gene diversity likely favors the abundance of this phylum in some anaerobic digestion systems. Further, we observe genetic redundancy within the Bacteroidetes group, which accounts for the preserved hydrolytic potential during acidosis. This work also uncovers new polysaccharide utilization loci involved in the deconstruction of various biomasses and proposes the model of acetylated glucomannan degradation by Bacteroidetes Acetylated glucomannan-enriched biomass is a common substrate for many industries, including pulp and paper production. Using naturally evolved cocktails of enzymes for biomass pretreatment could be an interesting alternative to the commonly used chemical pretreatments.
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Affiliation(s)
- Marie Bertucci
- Environmental Research and Innovation Department, Luxembourg Institute of Science and Technology, Belvaux, Luxembourg
- Laboratory of Bioengineering, Earth and Life Institute, Applied Microbiology, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Magdalena Calusinska
- Environmental Research and Innovation Department, Luxembourg Institute of Science and Technology, Belvaux, Luxembourg
| | - Xavier Goux
- Environmental Research and Innovation Department, Luxembourg Institute of Science and Technology, Belvaux, Luxembourg
| | - Corinne Rouland-Lefèvre
- Institute of Ecology and Environmental Sciences, Research Institute Development, Sorbonne Universités, Bondy, France
| | - Boris Untereiner
- Environmental Research and Innovation Department, Luxembourg Institute of Science and Technology, Belvaux, Luxembourg
| | - Pau Ferrer
- Environmental Research and Innovation Department, Luxembourg Institute of Science and Technology, Belvaux, Luxembourg
| | - Patrick A Gerin
- Laboratory of Bioengineering, Earth and Life Institute, Applied Microbiology, Université Catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Philippe Delfosse
- Environmental Research and Innovation Department, Luxembourg Institute of Science and Technology, Belvaux, Luxembourg
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41
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McKeen S, Young W, Mullaney J, Fraser K, McNabb WC, Roy NC. Infant Complementary Feeding of Prebiotics for theMicrobiome and Immunity. Nutrients 2019; 11:nu11020364. [PMID: 30744134 PMCID: PMC6412789 DOI: 10.3390/nu11020364] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2019] [Revised: 02/01/2019] [Accepted: 02/06/2019] [Indexed: 02/06/2023] Open
Abstract
Complementary feeding transitions infants from a milk-based diet to solid foods, providing essential nutrients to the infant and the developing gut microbiome while influencing immune development. Some of the earliest microbial colonisers readily ferment select oligosaccharides, influencing the ongoing establishment of the microbiome. Non-digestible oligosaccharides in prebiotic-supplemented formula and human milk oligosaccharides promote commensal immune-modulating bacteria such as Bifidobacterium, which decrease in abundance during weaning. Incorporating complex, bifidogenic, non-digestible carbohydrates during the transition to solid foods may present an opportunity to feed commensal bacteria and promote balanced concentrations of beneficial short chain fatty acid concentrations and vitamins that support gut barrier maturation and immunity throughout the complementary feeding window.
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Affiliation(s)
- Starin McKeen
- AgResearch, Food Nutrition & Health, Grasslands Research Centre, Private Bag 11008, Palmerston north4442, New Zealand.
- Riddet Institute, Massey University, Private Bag 11222, Palmerston North 4442, New Zealand.
- High-Value Nutrition National Science Challenge, Auckland, New Zealand.
| | - Wayne Young
- AgResearch, Food Nutrition & Health, Grasslands Research Centre, Private Bag 11008, Palmerston north4442, New Zealand.
- Riddet Institute, Massey University, Private Bag 11222, Palmerston North 4442, New Zealand.
- High-Value Nutrition National Science Challenge, Auckland, New Zealand.
| | - Jane Mullaney
- AgResearch, Food Nutrition & Health, Grasslands Research Centre, Private Bag 11008, Palmerston north4442, New Zealand.
- Riddet Institute, Massey University, Private Bag 11222, Palmerston North 4442, New Zealand.
- High-Value Nutrition National Science Challenge, Auckland, New Zealand.
| | - Karl Fraser
- AgResearch, Food Nutrition & Health, Grasslands Research Centre, Private Bag 11008, Palmerston north4442, New Zealand.
- Riddet Institute, Massey University, Private Bag 11222, Palmerston North 4442, New Zealand.
- High-Value Nutrition National Science Challenge, Auckland, New Zealand.
| | - Warren C McNabb
- Riddet Institute, Massey University, Private Bag 11222, Palmerston North 4442, New Zealand.
- High-Value Nutrition National Science Challenge, Auckland, New Zealand.
| | - Nicole C Roy
- AgResearch, Food Nutrition & Health, Grasslands Research Centre, Private Bag 11008, Palmerston north4442, New Zealand.
- Riddet Institute, Massey University, Private Bag 11222, Palmerston North 4442, New Zealand.
- High-Value Nutrition National Science Challenge, Auckland, New Zealand.
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42
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Zheng Q, Lu J, Wang Y, Jiao N. Genomic reconstructions and potential metabolic strategies of generalist and specialist heterotrophic bacteria associated with an estuarySynechococcusculture. FEMS Microbiol Ecol 2019; 95:5303724. [DOI: 10.1093/femsec/fiz017] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Accepted: 01/26/2019] [Indexed: 11/13/2022] Open
Affiliation(s)
- Qiang Zheng
- State Key Laboratory for Marine Environmental Science, Institute of Marine Microbes and Ecospheres, Xiamen University, Xiamen 361102, People's Republic of China
- College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, People's Republic of China
| | - Jiayao Lu
- State Key Laboratory for Marine Environmental Science, Institute of Marine Microbes and Ecospheres, Xiamen University, Xiamen 361102, People's Republic of China
- College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, People's Republic of China
| | - Yu Wang
- State Key Laboratory for Marine Environmental Science, Institute of Marine Microbes and Ecospheres, Xiamen University, Xiamen 361102, People's Republic of China
- College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, People's Republic of China
| | - Nianzhi Jiao
- State Key Laboratory for Marine Environmental Science, Institute of Marine Microbes and Ecospheres, Xiamen University, Xiamen 361102, People's Republic of China
- College of Ocean and Earth Sciences, Xiamen University, Xiamen 361102, People's Republic of China
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43
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Zafar H, Saier MH. Comparative genomics of transport proteins in seven Bacteroides species. PLoS One 2018; 13:e0208151. [PMID: 30517169 PMCID: PMC6281302 DOI: 10.1371/journal.pone.0208151] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Accepted: 11/12/2018] [Indexed: 01/29/2023] Open
Abstract
The communities of beneficial bacteria that live in our intestines, the gut microbiome, are important for the development and function of the immune system. Bacteroides species make up a significant fraction of the human gut microbiome, and can be probiotic and pathogenic, depending upon various genetic and environmental factors. These can cause disease conditions such as intra-abdominal sepsis, appendicitis, bacteremia, endocarditis, pericarditis, skin infections, brain abscesses and meningitis. In this study, we identify the transport systems and predict their substrates within seven Bacteroides species, all shown to be probiotic; however, four of them (B. thetaiotaomicron, B. vulgatus, B. ovatus, B. fragilis) can be pathogenic (probiotic and pathogenic; PAP), while B. cellulosilyticus, B. salanitronis and B. dorei are believed to play only probiotic roles (only probiotic; OP). The transport system characteristics of the four PAP and three OP strains were identified and tabulated, and results were compared among the seven strains, and with E. coli and Salmonella strains. The Bacteroides strains studied contain similarities and differences in the numbers and types of transport proteins tabulated, but both OP and PAP strains contain similar outer membrane carbohydrate receptors, pore-forming toxins and protein secretion systems, the similarities were noteworthy, but these Bacteroides strains showed striking differences with probiotic and pathogenic enteric bacteria, particularly with respect to their high affinity outer membrane receptors and auxiliary proteins involved in complex carbohydrate utilization. The results reveal striking similarities between the PAP and OP species of Bacteroides, and suggest that OP species may possess currently unrecognized pathogenic potential.
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Affiliation(s)
- Hassan Zafar
- Department of Molecular Biology, Division of Biological Sciences, University of California at San Diego, La Jolla, CA, United States of America
- Institute of Microbiology, University of Agriculture, Faisalabad, Punjab, Pakistan
| | - Milton H. Saier
- Department of Molecular Biology, Division of Biological Sciences, University of California at San Diego, La Jolla, CA, United States of America
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44
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Surface Exposure and Packing of Lipoproteins into Outer Membrane Vesicles Are Coupled Processes in Bacteroides. mSphere 2018; 3:3/6/e00559-18. [PMID: 30404931 PMCID: PMC6222051 DOI: 10.1128/msphere.00559-18] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022] Open
Abstract
Species from the Bacteroides genus are predominant members of the human gut microbiota. OMVs in Bacteroides have been shown to be important for the homeostasis of complex host-commensal relationships, mainly involving immune tolerance and protection from disease. OMVs carry many enzymatic activities involved in the cleavage of complex polysaccharides and have been proposed as public goods that can provide growth to other bacterial species by release of polysaccharide breakdown products into the gut lumen. This work shows that the presence of a negatively charged rich amino acid motif (LES) is required for efficient packing of the surface-exposed alpha-amylase SusG into OMVs. Our findings strongly suggest that surface exposure is coupled to packing of Bacteroides lipoproteins into OMVs. This is the first step in the generation of tailor-made probiotic interventions that can exploit LES-related sequences to generate Bacteroides strains displaying proteins of interest in OMVs. Outer membrane vesicles (OMVs) are spherical structures derived from the outer membranes (OMs) of Gram-negative bacteria. Bacteroides spp. are prominent components of the human gut microbiota, and OMVs produced by these species are proposed to play key roles in gut homeostasis. OMV biogenesis in Bacteroides is a poorly understood process. Here, we revisited the protein composition of Bacteroides thetaiotaomicron OMVs by mass spectrometry. We confirmed that OMVs produced by this organism contain large quantities of glycosidases and proteases, with most of them being lipoproteins. We found that most of these OMV-enriched lipoproteins are encoded by polysaccharide utilization loci (PULs), such as the sus operon. We examined the subcellular locations of the components of the Sus system and found a split localization; the alpha-amylase SusG is highly enriched in OMVs, while the oligosaccharide importer SusC remains mostly in the OM. We found that all OMV-enriched lipoproteins possess a lipoprotein export sequence (LES), and we show that this signal mediates translocation of SusG from the periplasmic face of the OM toward the extracellular milieu. Mutations in the LES motif caused defects in surface exposure and recruitment of SusG into OMVs. These experiments link, for the first time, surface exposure to recruitment of proteins into OMVs. We also show that surface-exposed SusG in OMVs is active and rescues the growth of bacterial cells incapable of growing on starch as the only carbon source. Our results support the role of OMVs as “public goods” that can be utilized by other organisms with different metabolic capabilities. IMPORTANCE Species from the Bacteroides genus are predominant members of the human gut microbiota. OMVs in Bacteroides have been shown to be important for the homeostasis of complex host-commensal relationships, mainly involving immune tolerance and protection from disease. OMVs carry many enzymatic activities involved in the cleavage of complex polysaccharides and have been proposed as public goods that can provide growth to other bacterial species by release of polysaccharide breakdown products into the gut lumen. This work shows that the presence of a negatively charged rich amino acid motif (LES) is required for efficient packing of the surface-exposed alpha-amylase SusG into OMVs. Our findings strongly suggest that surface exposure is coupled to packing of Bacteroides lipoproteins into OMVs. This is the first step in the generation of tailor-made probiotic interventions that can exploit LES-related sequences to generate Bacteroides strains displaying proteins of interest in OMVs.
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45
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Wexler AG, Schofield WB, Degnan PH, Folta-Stogniew E, Barry NA, Goodman AL. Human gut Bacteroides capture vitamin B 12 via cell surface-exposed lipoproteins. eLife 2018; 7:37138. [PMID: 30226189 PMCID: PMC6143338 DOI: 10.7554/elife.37138] [Citation(s) in RCA: 56] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Accepted: 08/26/2018] [Indexed: 01/02/2023] Open
Abstract
Human gut Bacteroides use surface-exposed lipoproteins to bind and metabolize complex polysaccharides. Although vitamins and other nutrients are also essential for commensal fitness, much less is known about how commensal bacteria compete with each other or the host for these critical resources. Unlike in Escherichia coli, transport loci for vitamin B12 (cobalamin) and other corrinoids in human gut Bacteroides are replete with conserved genes encoding proteins whose functions are unknown. Here we report that one of these proteins, BtuG, is a surface-exposed lipoprotein that is essential for efficient B12 transport in B. thetaiotaomicron. BtuG binds B12 with femtomolar affinity and can remove B12 from intrinsic factor, a critical B12 transport protein in humans. Our studies suggest that Bacteroides use surface-exposed lipoproteins not only for capturing polysaccharides, but also to acquire key vitamins in the gut. Eating is the first step in an hours-long process that extracts the nutrients we need to live. It not only nourishes us, but also a vast community of bacteria in our gut called the microbiota. The gut microbiota acts like an extension of our immune system and helps us stay healthy in many ways. For example, it blocks pathogens from making us sick. But too many gut bacteria in the wrong parts of our intestines can be harmful. Some people are prone to developing a dangerous overgrowth of bacteria in their small intestine where most of our dietary nutrients get absorbed. This overgrowth can lead to many problems including vitamin B12 deficiency even when they eat plenty of it. To understand why, scientists must learn how microbes affect our ability to absorb nutrients from food and how the microbes themselves capture nutrients like vitamin B12 as they pass through our digestive tract. Now, Wexler et al. show that some gut microbes may be able to pirate vitamin B12 from us as it passes through the digestive tract. Wexler et al. showed that a protein called BtuG on the surface of a type of gut bacteria called Bacteriodes grabs onto vitamin B12 with extraordinary strength. In fact, these bacterial proteins bind to vitamin B12 so strongly that they can even pry it away from our own vitamin B12 collecting protein. When Bacteriodes with and without BtuG were placed in mice with no gut bacteria of their own, bacteria with BtuG rapidly outcompeted those lacking the protein. The experiments suggest that competition for vitamin B12 among microbes has favored bacteria that are better at capturing the nutrient. More studies are needed to learn whether BtuG contributes to vitamin B12 deficiencies in humans with gut bacteria overgrowth and determine the best ways to combat such deficiencies.
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Affiliation(s)
- Aaron G Wexler
- Department of Microbial Pathogenesis, Yale University, New Haven, United States.,Microbial Sciences Institute, Yale University, New Haven, United States
| | - Whitman B Schofield
- Department of Microbial Pathogenesis, Yale University, New Haven, United States.,Microbial Sciences Institute, Yale University, New Haven, United States
| | - Patrick H Degnan
- Department of Microbial Pathogenesis, Yale University, New Haven, United States.,Microbial Sciences Institute, Yale University, New Haven, United States
| | - Ewa Folta-Stogniew
- W.M. Keck Biotechnology Resource Laboratory, Yale University School of Medicine, New Haven, United States
| | - Natasha A Barry
- Department of Microbial Pathogenesis, Yale University, New Haven, United States.,Microbial Sciences Institute, Yale University, New Haven, United States
| | - Andrew L Goodman
- Department of Microbial Pathogenesis, Yale University, New Haven, United States.,Microbial Sciences Institute, Yale University, New Haven, United States
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46
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TonB-dependent transport by the gut microbiota: novel aspects of an old problem. Curr Opin Struct Biol 2018; 51:35-43. [DOI: 10.1016/j.sbi.2018.03.001] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/03/2017] [Revised: 03/01/2018] [Accepted: 03/03/2018] [Indexed: 12/20/2022]
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47
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Tuson HH, Foley MH, Koropatkin NM, Biteen JS. The Starch Utilization System Assembles around Stationary Starch-Binding Proteins. Biophys J 2018; 115:242-250. [PMID: 29338841 PMCID: PMC6051301 DOI: 10.1016/j.bpj.2017.12.015] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2017] [Revised: 12/02/2017] [Accepted: 12/11/2017] [Indexed: 02/08/2023] Open
Abstract
Bacteroides thetaiotaomicron (Bt) is a prominent member of the human gut microbiota with an extensive capacity for glycan harvest. This bacterium expresses a five-protein complex in the outer membrane, called the starch utilization system (Sus), which binds, degrades, and imports starch into the cell. Sus is a model system for the many glycan-targeting polysaccharide utilization loci found in Bt and other members of the Bacteroidetes phylum. Our previous work has shown that SusG, a lipidated amylase in the outer membrane, explores the entire cell surface but diffuses more slowly as it interacts with starch. Here, we use a combination of single-molecule tracking, super-resolution imaging, reverse genetics, and proteomics to show that SusE and SusF, two proteins that bind starch, are immobile on the cell surface even when other members of the system are knocked out and under multiple different growth conditions. This observation suggests a new paradigm for protein complex formation: binding proteins form immobile complexes that transiently associate with a mobile enzyme partner.
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Affiliation(s)
- Hannah H Tuson
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan
| | - Matthew H Foley
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan
| | - Nicole M Koropatkin
- Department of Microbiology and Immunology, University of Michigan Medical School, Ann Arbor, Michigan.
| | - Julie S Biteen
- Department of Chemistry, University of Michigan, Ann Arbor, Michigan.
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48
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Genetic Variation of the SusC/SusD Homologs from a Polysaccharide Utilization Locus Underlies Divergent Fructan Specificities and Functional Adaptation in Bacteroides thetaiotaomicron Strains. mSphere 2018; 3:3/3/e00185-18. [PMID: 29794055 PMCID: PMC5967196 DOI: 10.1128/mspheredirect.00185-18] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2018] [Accepted: 04/13/2018] [Indexed: 11/20/2022] Open
Abstract
Dietary polysaccharides play a dominant role in shaping the composition and functionality of our gut microbiota. Dietary interventions using these microbiota-accessible carbohydrates (MACs) serve as a promising tool for manipulating the gut microbial community. However, our current gap in knowledge regarding microbial metabolic pathways that are involved in the degradation of these MACs has made the design of rational interventions difficult. The issue is further complicated by the diversity of pathways observed for the utilization of similar MACs, even in closely related microbial strains. Our current work focuses on divergent fructan utilization pathways in two closely related B. thetaiotaomicron strains and provides an integrated approach to characterize the molecular basis for strain-level functional differences. Genomic differences between gut-resident bacterial strains likely underlie significant interindividual variation in microbiome function. Traditional methods of determining community composition, such as 16S rRNA gene amplicon sequencing, fail to capture this functional diversity. Metagenomic approaches are a significant step forward in identifying strain-level sequence variants; however, given the current paucity of biochemical information, they too are limited to mainly low-resolution and incomplete functional predictions. Using genomic, biochemical, and molecular approaches, we identified differences in the fructan utilization profiles of two closely related Bacteroides thetaiotaomicron strains. B. thetaiotaomicron 8736 (Bt-8736) contains a fructan polysaccharide utilization locus (PUL) with a divergent susC/susD homolog gene pair that enables it to utilize inulin, differentiating this strain from other characterized Bt strains. Transfer of the distinct pair of susC/susD genes from Bt-8736 into the noninulin using type strain B. thetaiotaomicron VPI-5482 resulted in inulin use by the recipient strain, Bt(8736-2). The presence of the divergent susC/susD gene pair alone enabled the hybrid Bt(8736-2) strain to outcompete the wild-type strain in vivo in mice fed an inulin diet. Further, we discovered that the susC/susD homolog gene pair facilitated import of inulin into the periplasm without surface predigestion by an endo-acting enzyme, possibly due to the short average chain length of inulin compared to many other polysaccharides. Our data builds upon recent reports of dietary polysaccharide utilization mechanisms found in members of the Bacteroides genus and demonstrates how the acquisition of two genes can alter the functionality and success of a strain within the gut. IMPORTANCE Dietary polysaccharides play a dominant role in shaping the composition and functionality of our gut microbiota. Dietary interventions using these microbiota-accessible carbohydrates (MACs) serve as a promising tool for manipulating the gut microbial community. However, our current gap in knowledge regarding microbial metabolic pathways that are involved in the degradation of these MACs has made the design of rational interventions difficult. The issue is further complicated by the diversity of pathways observed for the utilization of similar MACs, even in closely related microbial strains. Our current work focuses on divergent fructan utilization pathways in two closely related B. thetaiotaomicron strains and provides an integrated approach to characterize the molecular basis for strain-level functional differences.
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49
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Santilli AD, Dawson EM, Whitehead KJ, Whitehead DC. Nonmicrobicidal Small Molecule Inhibition of Polysaccharide Metabolism in Human Gut Microbes: A Potential Therapeutic Avenue. ACS Chem Biol 2018; 13:1165-1172. [PMID: 29660284 DOI: 10.1021/acschembio.8b00309] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
A new approach for the nonmicrobicidal phenotypic manipulation of prominent gastrointestinal microbes is presented. Low micromolar concentrations of a chemical probe, acarbose, can selectively inhibit the Starch Utilization System and ablate the ability of Bacteroides thetaiotaomicron and B. fragilis strains to metabolize potato starch and pullulan. This strategy has potential therapeutic relevance for the selective modulation of the GI microbiota in a nonmicrobicidal manner.
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Affiliation(s)
- Anthony D. Santilli
- Department of Chemistry, Clemson University, Clemson, South Carolina 29634, United States
| | - Elizabeth M. Dawson
- Department of Chemistry, Clemson University, Clemson, South Carolina 29634, United States
| | - Kristi J. Whitehead
- Department of Biological Sciences, Clemson University, Clemson, South Carolina 29634, United States
| | - Daniel C. Whitehead
- Department of Chemistry, Clemson University, Clemson, South Carolina 29634, United States
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50
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Abstract
In red algae, the most abundant principal cell wall polysaccharides are mixed galactan agars, of which agarose is a common component. While bioconversion of agarose is predominantly catalyzed by bacteria that live in the oceans, agarases have been discovered in microorganisms that inhabit diverse terrestrial ecosystems, including human intestines. Here we comprehensively define the structure-function relationship of the agarolytic pathway from the human intestinal bacterium Bacteroides uniformis (Bu) NP1. Using recombinant agarases from Bu NP1 to completely depolymerize agarose, we demonstrate that a non-agarolytic Bu strain can grow on GAL released from agarose. This relationship underscores that rare nutrient utilization by intestinal bacteria is facilitated by the acquisition of highly specific enzymes that unlock inaccessible carbohydrate resources contained within unusual polysaccharides. Intriguingly, the agarolytic pathway is differentially distributed throughout geographically distinct human microbiomes, reflecting a complex historical context for agarose consumption by human beings.
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