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Zhang X, Wu K, Han Z, Chen Z, Liu Z, Sun Z, Shao L, Zhao Z, Zhou L. Microbial diversity and biogeochemical cycling potential in deep-sea sediments associated with seamount, trench, and cold seep ecosystems. Front Microbiol 2022; 13:1029564. [PMID: 36386615 PMCID: PMC9650238 DOI: 10.3389/fmicb.2022.1029564] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/27/2022] [Accepted: 10/11/2022] [Indexed: 11/02/2023] Open
Abstract
Due to their extreme water depths and unique physicochemical conditions, deep-sea ecosystems develop uncommon microbial communities, which play a vital role in biogeochemical cycling. However, the differences in the compositions and functions of the microbial communities among these different geographic structures, such as seamounts (SM), marine trenches (MT), and cold seeps (CS), are still not fully understood. In the present study, sediments were collected from SM, MT, and CS in the Southwest Pacific Ocean, and the compositions and functions of the microbial communities were investigated by using amplicon sequencing combined with in-depth metagenomics. The results revealed that significantly higher richness levels and diversities of the microbial communities were found in SM sediments, followed by CS, and the lowest richness levels and diversities were found in MT sediments. Acinetobacter was dominant in the CS sediments and was replaced by Halomonas and Pseudomonas in the SM and MT sediments. We demonstrated that the microbes in deep-sea sediments were diverse and were functionally different (e.g., carbon, nitrogen, and sulfur cycling) from each other in the seamount, trench, and cold seep ecosystems. These results improved our understanding of the compositions, diversities and functions of microbial communities in the deep-sea environment.
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Affiliation(s)
- Xiaoyong Zhang
- University Joint Laboratory of Guangdong Province, Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou, China
| | - Keyue Wu
- University Joint Laboratory of Guangdong Province, Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou, China
| | - Zhuang Han
- Institute of Deep-Sea Science and Engineering, Chinese Academy of Science, Sanya, China
| | - Zihui Chen
- University Joint Laboratory of Guangdong Province, Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou, China
| | - Zhiying Liu
- University Joint Laboratory of Guangdong Province, Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou, China
| | - Zuwang Sun
- University Joint Laboratory of Guangdong Province, Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou, China
| | - Liyi Shao
- University Joint Laboratory of Guangdong Province, Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou, China
| | - Zelong Zhao
- Liaoning Key Lab of Germplasm Improvement and Fine Seed Breeding of Marine Aquatic Animals, Liaoning Ocean and Fisheries Science Research Institute, Dalian, China
| | - Lei Zhou
- University Joint Laboratory of Guangdong Province, Hong Kong and Macao Region on Marine Bioresource Conservation and Exploitation, College of Marine Sciences, South China Agricultural University, Guangzhou, China
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Hou Y, Li B, Xu G, Li D, Zhang C, Jia R, Li Q, Zhu J. Dynamic and Assembly of Benthic Bacterial Community in an Industrial-Scale In-Pond Raceway Recirculating Culture System. Front Microbiol 2022; 12:797817. [PMID: 35003028 PMCID: PMC8733461 DOI: 10.3389/fmicb.2021.797817] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2021] [Accepted: 12/06/2021] [Indexed: 11/13/2022] Open
Abstract
To reduce water utilization, limit environmental pollution, and guarantee aquatic production and quality, the in-pond raceway recirculating culture system (IPRS) has been developed and is widely used. The effectiveness and sustainability of IPRSs rely on a good understanding of the ecological processes related to bacterial communities in the purification area. In this study, we investigated the dynamics and assembly mechanisms of benthic bacterial communities in the purification area of an industrial-scale IRPS. We found significant temporal and spatial variations in the sediment characteristics and benthic bacterial communities of the IPRS, although correlation analyses revealed a very limited relationship between them. Among the different culture stages, we identified numerous benthic bacteria with different abundances. Abundances of the phyla Bacteroidota and Desulfobacterota decreased whereas those of Myxococcota and Gemmatimonadota increased as the culture cycle progressed. Co-occurrence networks revealed that the bacterial community was less complex but more stable in the IPRS at the final stage compared with the initial stage. The neutral community model (NCM) showed that stochastic processes were the dominant ecological processes shaping the assembly of the benthic bacterial community. The null model suggested that homogenizing dispersal was more powerful than dispersal limitation and drift in regulating the assembly of the community. These findings indicate that the benthic microbial communities in purification areas of the IPRS may not be affected by the deposited wastes, and a more stable benthic microbial communities were formed and mainly driven by stochastic processes. However, the benthic microbial communities in the purification area at the end of the culturing stage was characterized by potentially inhibited organic matter degradation and carbon and sulfur cycling abilities, which was not corresponding to the purification area’s function. From this point on, the IPRS, especially the purification area was needed to be further optimized and improved.
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Affiliation(s)
- Yiran Hou
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China.,Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, China
| | - Bing Li
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China.,Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, China
| | - Gangchun Xu
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China.,Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, China
| | - Da Li
- Ocean and Fishery Research Institute of Rizhao, Rizhao, China
| | - Chengfeng Zhang
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China.,Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, China
| | - Rui Jia
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China.,Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, China
| | - Quanjie Li
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China
| | - Jian Zhu
- Key Laboratory of Freshwater Fisheries and Germplasm Resources Utilization, Ministry of Agriculture and Rural Affairs, Freshwater Fisheries Research Center, Chinese Academy of Fishery Sciences, Wuxi, China.,Wuxi Fisheries College, Nanjing Agricultural University, Wuxi, China
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Tomek MB, Janesch B, Braun ML, Taschner M, Figl R, Grünwald-Gruber C, Coyne MJ, Blaukopf M, Altmann F, Kosma P, Kählig H, Comstock LE, Schäffer C. A Combination of Structural, Genetic, Phenotypic and Enzymatic Analyses Reveals the Importance of a Predicted Fucosyltransferase to Protein O-Glycosylation in the Bacteroidetes. Biomolecules 2021; 11:1795. [PMID: 34944439 PMCID: PMC8698959 DOI: 10.3390/biom11121795] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2021] [Revised: 11/21/2021] [Accepted: 11/23/2021] [Indexed: 12/20/2022] Open
Abstract
Diverse members of the Bacteroidetes phylum have general protein O-glycosylation systems that are essential for processes such as host colonization and pathogenesis. Here, we analyzed the function of a putative fucosyltransferase (FucT) family that is widely encoded in Bacteroidetes protein O-glycosylation genetic loci. We studied the FucT orthologs of three Bacteroidetes species-Tannerella forsythia, Bacteroides fragilis, and Pedobacter heparinus. To identify the linkage created by the FucT of B. fragilis, we elucidated the full structure of its nine-sugar O-glycan and found that l-fucose is linked β1,4 to glucose. Of the two fucose residues in the T. forsythia O-glycan, the fucose linked to the reducing-end galactose was shown by mutational analysis to be l-fucose. Despite the transfer of l-fucose to distinct hexose sugars in the B. fragilis and T. forsythia O-glycans, the FucT orthologs from B. fragilis, T. forsythia, and P. heparinus each cross-complement the B. fragilis ΔBF4306 and T. forsythia ΔTanf_01305 FucT mutants. In vitro enzymatic analyses showed relaxed acceptor specificity of the three enzymes, transferring l-fucose to various pNP-α-hexoses. Further, glycan structural analysis together with fucosidase assays indicated that the T. forsythia FucT links l-fucose α1,6 to galactose. Given the biological importance of fucosylated carbohydrates, these FucTs are promising candidates for synthetic glycobiology.
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Affiliation(s)
- Markus B. Tomek
- NanoGlycobiology Unit, Institute of Biologically Inspired Materials, Department of NanoBiotechnology, Universität für Bodenkultur Wien, Muthgasse 11, A-1190 Vienna, Austria; (M.B.T.); (B.J.); (M.L.B.); (M.T.)
| | - Bettina Janesch
- NanoGlycobiology Unit, Institute of Biologically Inspired Materials, Department of NanoBiotechnology, Universität für Bodenkultur Wien, Muthgasse 11, A-1190 Vienna, Austria; (M.B.T.); (B.J.); (M.L.B.); (M.T.)
| | - Matthias L. Braun
- NanoGlycobiology Unit, Institute of Biologically Inspired Materials, Department of NanoBiotechnology, Universität für Bodenkultur Wien, Muthgasse 11, A-1190 Vienna, Austria; (M.B.T.); (B.J.); (M.L.B.); (M.T.)
| | - Manfred Taschner
- NanoGlycobiology Unit, Institute of Biologically Inspired Materials, Department of NanoBiotechnology, Universität für Bodenkultur Wien, Muthgasse 11, A-1190 Vienna, Austria; (M.B.T.); (B.J.); (M.L.B.); (M.T.)
| | - Rudolf Figl
- Institute of Biochemistry, Department of Chemistry, Universität für Bodenkultur Wien, Muthgasse 18, A-1190 Vienna, Austria; (R.F.); (C.G.-G.); (F.A.)
| | - Clemens Grünwald-Gruber
- Institute of Biochemistry, Department of Chemistry, Universität für Bodenkultur Wien, Muthgasse 18, A-1190 Vienna, Austria; (R.F.); (C.G.-G.); (F.A.)
| | - Michael J. Coyne
- Department of Microbiology and the Duchossois Family Institute, University of Chicago, KCBD, 900 E. 57th Street, Chicago, IL 60637, USA; (M.J.C.); (L.E.C.)
| | - Markus Blaukopf
- Institute of Organic Chemistry, Department of Chemistry, Universität für Bodenkultur Wien, Muthgasse 18, A-1190 Vienna, Austria; (M.B.); (P.K.)
| | - Friedrich Altmann
- Institute of Biochemistry, Department of Chemistry, Universität für Bodenkultur Wien, Muthgasse 18, A-1190 Vienna, Austria; (R.F.); (C.G.-G.); (F.A.)
| | - Paul Kosma
- Institute of Organic Chemistry, Department of Chemistry, Universität für Bodenkultur Wien, Muthgasse 18, A-1190 Vienna, Austria; (M.B.); (P.K.)
| | - Hanspeter Kählig
- Department of Organic Chemistry, Faculty of Chemistry, University of Vienna, Währinger Strasse 38, A-1090 Vienna, Austria;
| | - Laurie E. Comstock
- Department of Microbiology and the Duchossois Family Institute, University of Chicago, KCBD, 900 E. 57th Street, Chicago, IL 60637, USA; (M.J.C.); (L.E.C.)
| | - Christina Schäffer
- NanoGlycobiology Unit, Institute of Biologically Inspired Materials, Department of NanoBiotechnology, Universität für Bodenkultur Wien, Muthgasse 11, A-1190 Vienna, Austria; (M.B.T.); (B.J.); (M.L.B.); (M.T.)
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Peng Y, Jiang L, Seo J, Li Z, Choe H, Jeong JC, Kim SW, Kim YM, Kim CY, Lee J. Pedobacter endophyticus sp. nov., an endophytic bacterium isolated from Carex pumila. Int J Syst Evol Microbiol 2021; 71. [PMID: 34296986 DOI: 10.1099/ijsem.0.004915] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
An aerobic, Gram-stain-negative, weak-motile, short-rod-shaped bacterial strain, designated JBR3-12T, was isolated from halophyte Carex pumila plants, and its taxonomic position was investigated by using a polyphasic taxonomic approach. The strain produced a pink pigment on tryptic soy agar and grew optimally at 25 °C, pH 8 and in the presence of 3 % (w/v) NaCl. Results of phylogenetic analysis based on 16S rRNA gene sequences showed that strain JBR3-12T formed a lineage within the genus Pedobacter and was most closely related to Pedobacter sandarakinus DS-27T (98.0 %) and Pedobacter agri PB92T (97.6 %). The DNA G+C content of the genome was 41.3 mol%; the whole genome length was 5 426 070 bp. The major fatty acids of JBR3-12T were iso-C15 : 0, summed feature 3 (comprising C16 : 1 ω6c and/or C16 : 1 ω7c) and iso-C17 : 0 3-OH. The predominant polar lipid was phosphatidylethanolamine. The predominant quinone was menaquinone-7. Based on its phenotypic, phylogenetic and genotypic features, strain JBR3-12T is proposed to represent a novel species of the genus Pedobacter, for which the name is Pedobacter endophyticus sp. nov. The type strain is JBR3-12T (=KCTC 82363T=NBRC 114901T).
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Affiliation(s)
- Yuxin Peng
- Korean Collection for Type Cultures (KCTC), Biological Resource Center, Korea Research Institute of Bioscience and Biotechnology, Jeongeup 56212, Republic of Korea
- Department of Agriculture and Life Sciences, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Lingmin Jiang
- Korean Collection for Type Cultures (KCTC), Biological Resource Center, Korea Research Institute of Bioscience and Biotechnology, Jeongeup 56212, Republic of Korea
| | - Jiyoon Seo
- Korean Collection for Type Cultures (KCTC), Biological Resource Center, Korea Research Institute of Bioscience and Biotechnology, Jeongeup 56212, Republic of Korea
| | - Zhun Li
- Korean Collection for Type Cultures (KCTC), Biological Resource Center, Korea Research Institute of Bioscience and Biotechnology, Jeongeup 56212, Republic of Korea
| | - Hanna Choe
- Korean Collection for Type Cultures (KCTC), Biological Resource Center, Korea Research Institute of Bioscience and Biotechnology, Jeongeup 56212, Republic of Korea
| | - Jae Cheol Jeong
- Korean Collection for Type Cultures (KCTC), Biological Resource Center, Korea Research Institute of Bioscience and Biotechnology, Jeongeup 56212, Republic of Korea
| | - Suk Weon Kim
- Korean Collection for Type Cultures (KCTC), Biological Resource Center, Korea Research Institute of Bioscience and Biotechnology, Jeongeup 56212, Republic of Korea
| | - Young-Min Kim
- Department of Agriculture and Life Sciences, Chonnam National University, Gwangju 61186, Republic of Korea
| | - Cha Young Kim
- Korean Collection for Type Cultures (KCTC), Biological Resource Center, Korea Research Institute of Bioscience and Biotechnology, Jeongeup 56212, Republic of Korea
| | - Jiyoung Lee
- Korean Collection for Type Cultures (KCTC), Biological Resource Center, Korea Research Institute of Bioscience and Biotechnology, Jeongeup 56212, Republic of Korea
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Terada A, Komatsu D, Ogawa T, Flamandita D, Sahlan M, Nishimura M, Yohda M. Isolation of cyanide-degrading bacteria and molecular characterization of its cyanide-degrading nitrilase. Biotechnol Appl Biochem 2020; 69:183-189. [PMID: 33377552 DOI: 10.1002/bab.2095] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Accepted: 12/25/2020] [Indexed: 11/07/2022]
Abstract
Hydrogen cyanide is an industrially important chemical, and its annual production is more than 1.5 million tons. Because of its toxicity, the cyanide-containing effluents from industries have caused many environmental problems. Among various methods to treat the contaminated soils or water, the biological degradation is regarded to be promising. We isolated two cyanide-degrading microorganisms, Pedobacter sp. EBE-1 and Bacillus sp. EBE-2, from soil contaminated with cyanide. Among these bacteria, Bacillus sp. EBE-2 exhibited significantly a high cyanide-degrading ability. Bacillus sp. EBE-2 might be used for the remediation of cyanide contaminated water or soil. A nitrilase gene was cloned from Bacillus sp. EBE-2. Bacillus nitrilase was expressed in Escherichia coli and purified. Bacillus nitrilase exhibited cyanide-degrading activity as a large oligomer. Since formic acid formation from cyanide was observed, Bacillus nitrilase is likely to be a cyanide hydrolase. Although there exist various homologous enzymes annotated as carbon-nitrogen family hydrolases, this is the first report on the cyanide degrading activity. The structure and catalytic site of Bacillus nitrilase were studied by homology modeling and molecular docking simulation.
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Affiliation(s)
- Ayane Terada
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Koganei, Tokyo, Japan
| | - Daisuke Komatsu
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Koganei, Tokyo, Japan
- EnBio Engineering, Chiyoda, Tokyo, Japan
| | - Takahiro Ogawa
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Koganei, Tokyo, Japan
| | - Darin Flamandita
- Department of Chemical Engineering, Universitas Indonesia, Depok, Indonesia
| | - Muhamad Sahlan
- Department of Chemical Engineering, Universitas Indonesia, Depok, Indonesia
| | | | - Masafumi Yohda
- Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, Koganei, Tokyo, Japan
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Wang X, Han Q, Chen G, Zhang W, Liu W. A Putative Type II Secretion System Is Involved in Cellulose Utilization in Cytophaga hutchisonii. Front Microbiol 2017; 8:1482. [PMID: 28848505 PMCID: PMC5553014 DOI: 10.3389/fmicb.2017.01482] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Accepted: 07/24/2017] [Indexed: 11/23/2022] Open
Abstract
Cytophaga hutchinsonii is a gliding cellulolytic bacterium that degrades cellulose in a substrate contact-dependent manner. Specific proteins are speculated to be translocated to its extracellular milieu or outer membrane surface to participate in adhesion to cellulose and further digestion. In this study, we show that three orthologous genes encoding the major components (T2S-D, -F, and -G) of type II secretion system (T2SS) are involved in cellulose degradation but not in cell motility. The individual disruption of the three t2s genes results in a significantly retarded growth on cellobiose, regenerated amorphous cellulose, and Avicel cellulose. Enzymatic analyses demonstrate that, whereas the endoglucanase activity of the t2s mutant cells is increased, the β-glucosidase activity is remarkably reduced compared to that of WT cells. Further analyses reveal that the t2s mutant cells not only exhibit a different profile of cellulose-bound outer membrane proteins from that of wild-type cells, but also display a significant decrease in their capability to adhere to cellulose. These results indicate that a functional link exits between the putative T2SS and cellulose utilization in C. hutchinsonii, and thus provide a conceptual framework to understand the unique strategy deployed by C. hutchinsonii to assimilate cellulose.
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Affiliation(s)
- Xia Wang
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong UniversityJinan, China
| | - Qingqing Han
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong UniversityJinan, China
| | - Guanjun Chen
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong UniversityJinan, China
| | - Weixin Zhang
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong UniversityJinan, China
| | - Weifeng Liu
- State Key Laboratory of Microbial Technology, School of Life Science, Shandong UniversityJinan, China
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Moore EK, Hopmans EC, Rijpstra WIC, Villanueva L, Damsté JSS. Elucidation and identification of amino acid containing membrane lipids using liquid chromatography/high-resolution mass spectrometry. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2016; 30:739-750. [PMID: 27281845 DOI: 10.1002/rcm.7503] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
RATIONALE Intact polar lipids (IPLs) are the building blocks of cell membranes, and amino acid containing IPLs have been observed to be involved in response to changing environmental conditions in various species of bacteria. High-performance liquid chromatography/mass spectrometry (HPLC/MS) has become the primary method for analysis of IPLs. Many glycerol-free amino acid containing membrane lipids (AA-IPLs), which are structurally different than abundant aminophospholipids, have not been characterized using HPLC/MS. This results in many lipids remaining unrecognized in IPL analysis of microbial cultures and environmental samples, hampering the study of their occurrence and functionality. METHODS We analyzed the amino acid containing IPLs of a number of bacteria (i.e. Gluconobacter cerinus, Cyclobacterium marinus, Rhodobacter sphaeroides, and Pedobacter heparinus) in order to decipher fragmentation pathways, and explore potential novel lipid structures using HPLC/electrospray ionization ion trap MS (HPLC/ESI-IT-MS) and HPLC/high-resolution MS (HPLC/HRMS). RESULTS We report differentiation between glutamine and lysine lipids with the same nominal masses, novel MS fragmentation pathways of cytolipin, the lipopeptides cerilipin and flavolipin, head group hydroxylated ornithine lipids, and the novel identification of cerilipin with a hydroxylated fatty acid. CONCLUSIONS Non-glycerol AA lipids can be readily recognized as their fragmentation follows a clear pattern with initial dehydration or other loss from the head group, followed by fatty acid losses resulting in a diagnostic fragment ion. Higher level MSn and HRMS are valuable tools in characterizing AA lipid head group structural components.
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Draft Genome Sequence of Pedobacter sp. Strain Hv1, an Isolate from Medicinal Leech Mucosal Castings. GENOME ANNOUNCEMENTS 2015; 3:3/6/e01469-15. [PMID: 26679583 PMCID: PMC4683228 DOI: 10.1128/genomea.01469-15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/02/2022]
Abstract
The Pedobacter sp. Hv1 strain was isolated from the medicinal leech, Hirudo verbana, mucosal castings. These mucosal sheds have been demonstrated to play a role in horizontal symbiont transmission. Here, we report the draft 4.9 Mbp genome sequence of Pedobacter sp. strain Hv1.
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Structural and biochemical characterization of novel bacterial α-galactosidases belonging to glycoside hydrolase family 31. Biochem J 2015; 469:145-58. [DOI: 10.1042/bj20150261] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/27/2015] [Accepted: 05/05/2015] [Indexed: 11/17/2022]
Abstract
We identified two bacterial enzymes as the first members that displayed α-galactosidase activity and the crystal structures provided insights into their novel substrate specificity. This is the first report of α-galactosidases which belong to the GH31 family.
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Nurk S, Bankevich A, Antipov D, Gurevich AA, Korobeynikov A, Lapidus A, Prjibelski AD, Pyshkin A, Sirotkin A, Sirotkin Y, Stepanauskas R, Clingenpeel SR, Woyke T, McLean JS, Lasken R, Tesler G, Alekseyev MA, Pevzner PA. Assembling single-cell genomes and mini-metagenomes from chimeric MDA products. J Comput Biol 2014; 20:714-37. [PMID: 24093227 DOI: 10.1089/cmb.2013.0084] [Citation(s) in RCA: 979] [Impact Index Per Article: 97.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023] Open
Abstract
Recent advances in single-cell genomics provide an alternative to largely gene-centric metagenomics studies, enabling whole-genome sequencing of uncultivated bacteria. However, single-cell assembly projects are challenging due to (i) the highly nonuniform read coverage and (ii) a greatly elevated number of chimeric reads and read pairs. While recently developed single-cell assemblers have addressed the former challenge, methods for assembling highly chimeric reads remain poorly explored. We present algorithms for identifying chimeric edges and resolving complex bulges in de Bruijn graphs, which significantly improve single-cell assemblies. We further describe applications of the single-cell assembler SPAdes to a new approach for capturing and sequencing "microbial dark matter" that forms small pools of randomly selected single cells (called a mini-metagenome) and further sequences all genomes from the mini-metagenome at once. On single-cell bacterial datasets, SPAdes improves on the recently developed E+V-SC and IDBA-UD assemblers specifically designed for single-cell sequencing. For standard (cultivated monostrain) datasets, SPAdes also improves on A5, ABySS, CLC, EULER-SR, Ray, SOAPdenovo, and Velvet. Thus, recently developed single-cell assemblers not only enable single-cell sequencing, but also improve on conventional assemblers on their own turf. SPAdes is available for free online download under a GPLv2 license.
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Affiliation(s)
- Sergey Nurk
- 1 Algorithmic Biology Laboratory, St. Petersburg Academic University , Russian Academy of Sciences, St. Petersburg, Russia
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11
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Ntougias S, Lapidus A, Han J, Mavromatis K, Pati A, Chen A, Klenk HP, Woyke T, Fasseas C, Kyrpides NC, Zervakis GI. High quality draft genome sequence of Olivibacter sitiensis type strain (AW-6(T)), a diphenol degrader with genes involved in the catechol pathway. Stand Genomic Sci 2014; 9:783-93. [PMID: 25197463 PMCID: PMC4149018 DOI: 10.4056/sigs.5088950] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Olivibacter sitiensis Ntougias et al. 2007 is a member of the family Sphingobacteriaceae, phylum Bacteroidetes. Members of the genus Olivibacter are phylogenetically diverse and of significant interest. They occur in diverse habitats, such as rhizosphere and contaminated soils, viscous wastes, composts, biofilter clean-up facilities on contaminated sites and cave environments, and they are involved in the degradation of complex and toxic compounds. Here we describe the features of O. sitiensis AW-6T, together with the permanent-draft genome sequence and annotation. The organism was sequenced under the Genomic Encyclopedia for Bacteria and Archaea (GEBA) project at the DOE Joint Genome Institute and is the first genome sequence of a species within the genus Olivibacter. The genome is 5,053,571 bp long and is comprised of 110 scaffolds with an average GC content of 44.61%. Of the 4,565 genes predicted, 4,501 were protein-coding genes and 64 were RNA genes. Most protein-coding genes (68.52%) were assigned to a putative function. The identification of 2-keto-4-pentenoate hydratase/2-oxohepta-3-ene-1,7-dioic acid hydratase-coding genes indicates involvement of this organism in the catechol catabolic pathway. In addition, genes encoding for β-1,4-xylanases and β-1,4-xylosidases reveal the xylanolytic action of O. sitiensis.
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Affiliation(s)
- Spyridon Ntougias
- Democritus University of Thrace, Department of Environmental Engineering, Laboratory of Wastewater Management and Treatment Technologies, Xanthi, Greece
| | - Alla Lapidus
- Department of Energy Joint Genome Institute, Genome Biology Program, Walnut Creek, CA, USA
| | - James Han
- Department of Energy Joint Genome Institute, Genome Biology Program, Walnut Creek, CA, USA
| | | | - Amrita Pati
- Department of Energy Joint Genome Institute, Genome Biology Program, Walnut Creek, CA, USA
| | - Amy Chen
- Biological Data Management and Technology Center, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Hans-Peter Klenk
- Leibniz Institute DSMZ - German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany
| | - Tanja Woyke
- Department of Energy Joint Genome Institute, Genome Biology Program, Walnut Creek, CA, USA
| | - Constantinos Fasseas
- Agricultural University of Athens, Electron Microscopy Laboratory, Athens, Greece
| | - Nikos C Kyrpides
- Department of Energy Joint Genome Institute, Genome Biology Program, Walnut Creek, CA, USA ; King Abdulaziz University, Jeddah, Saudi Arabia
| | - Georgios I Zervakis
- Agricultural University of Athens, Laboratory of General and Agricultural Microbiology, Athens, Greece
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12
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Collén PN, Jeudy A, Sassi JF, Groisillier A, Czjzek M, Coutinho PM, Helbert W. A novel unsaturated β-glucuronyl hydrolase involved in ulvan degradation unveils the versatility of stereochemistry requirements in family GH105. J Biol Chem 2014; 289:6199-211. [PMID: 24407291 DOI: 10.1074/jbc.m113.537480] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
Ulvans are cell wall matrix polysaccharides in green algae belonging to the genus Ulva. Enzymatic degradation of the polysaccharide by ulvan lyases leads to the production of oligosaccharides with an unsaturated β-glucuronyl residue located at the non-reducing end. Exploration of the genomic environment around the Nonlabens ulvanivorans (previously Percicivirga ulvanivorans) ulvan lyase revealed a gene highly similar to known unsaturated uronyl hydrolases classified in the CAZy glycoside hydrolase family 105. The gene was cloned, the protein was overexpressed in Escherichia coli, and enzymology experiments demonstrated its unsaturated β-glucuronyl activity. Kinetic analysis of purified oligo-ulvans incubated with the new enzyme showed that the full substrate specificity is attained by three subsites that preferentially bind anionic residues (sulfated rhamnose, glucuronic/iduronic acid). The three-dimensional crystal structure of the native enzyme reveals that a trimeric organization is required for substrate binding and recognition at the +2 binding subsite. This novel unsaturated β-glucuronyl hydrolase is part of a previously uncharacterized subgroup of GH105 members and exhibits only a very limited sequence similarity to known unsaturated β-glucuronyl sequences previously found only in family GH88. Clan-O formed by families GH88 and GH105 was singular in the fact that it covered families acting on both axial and equatorial glycosidic linkages, respectively. The overall comparison of active site structures between enzymes from these two families highlights how that within family GH105, and unlike for classical glycoside hydrolysis, the hydrolysis of vinyl ether groups from unsaturated saccharides occurs independently of the α or β configuration of the cleaved linkage.
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Affiliation(s)
- Pi Nyvall Collén
- From the CNRS, Université Pierre et Marie Curie-Paris 6, Unité Mixte de Recherche 7139 "Marine Plants and Biomolecules," Station Biologique, F-29682 Roscoff Cedex, France
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13
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Nakamichi Y, Mikami B, Murata K, Hashimoto W. Crystal structure of a bacterial unsaturated glucuronyl hydrolase with specificity for heparin. J Biol Chem 2014; 289:4787-97. [PMID: 24403065 DOI: 10.1074/jbc.m113.522573] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Extracellular matrix molecules such as glycosaminoglycans (GAGs) are typical targets for some pathogenic bacteria, which allow adherence to host cells. Bacterial polysaccharide lyases depolymerize GAGs in β-elimination reactions, and the resulting unsaturated disaccharides are subsequently degraded to constituent monosaccharides by unsaturated glucuronyl hydrolases (UGLs). UGL substrates are classified as 1,3- and 1,4-types based on the glycoside bonds. Unsaturated chondroitin and heparin disaccharides are typical members of 1,3- and 1,4-types, respectively. Here we show the reaction modes of bacterial UGLs with unsaturated heparin disaccharides by x-ray crystallography, docking simulation, and site-directed mutagenesis. Although streptococcal and Bacillus UGLs were active on unsaturated heparin disaccharides, those preferred 1,3- rather than 1,4-type substrates. The genome of GAG-degrading Pedobacter heparinus encodes 13 UGLs. Of these, Phep_2830 is known to be specific for unsaturated heparin disaccharides. The crystal structure of Phep_2830 was determined at 1.35-Å resolution. In comparison with structures of streptococcal and Bacillus UGLs, a pocket-like structure and lid loop at subsite +1 are characteristic of Phep_2830. Docking simulations of Phep_2830 with unsaturated heparin disaccharides demonstrated that the direction of substrate pyranose rings differs from that in unsaturated chondroitin disaccharides. Acetyl groups of unsaturated heparin disaccharides are well accommodated in the pocket at subsite +1, and aromatic residues of the lid loop are required for stacking interactions with substrates. Thus, site-directed mutations of the pocket and lid loop led to significantly reduced enzyme activity, suggesting that the pocket-like structure and lid loop are involved in the recognition of 1,4-type substrates by UGLs.
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Affiliation(s)
- Yusuke Nakamichi
- From the Laboratory of Basic and Applied Molecular Biotechnology, Division of Food Science and Biotechnology, Graduate School of Agriculture, and
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14
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Chin CS, Alexander DH, Marks P, Klammer AA, Drake J, Heiner C, Clum A, Copeland A, Huddleston J, Eichler EE, Turner SW, Korlach J. Nonhybrid, finished microbial genome assemblies from long-read SMRT sequencing data. Nat Methods 2013; 10:563-9. [PMID: 23644548 DOI: 10.1038/nmeth.2474] [Citation(s) in RCA: 3121] [Impact Index Per Article: 283.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2013] [Accepted: 04/04/2013] [Indexed: 02/08/2023]
Abstract
We present a hierarchical genome-assembly process (HGAP) for high-quality de novo microbial genome assemblies using only a single, long-insert shotgun DNA library in conjunction with Single Molecule, Real-Time (SMRT) DNA sequencing. Our method uses the longest reads as seeds to recruit all other reads for construction of highly accurate preassembled reads through a directed acyclic graph-based consensus procedure, which we follow with assembly using off-the-shelf long-read assemblers. In contrast to hybrid approaches, HGAP does not require highly accurate raw reads for error correction. We demonstrate efficient genome assembly for several microorganisms using as few as three SMRT Cell zero-mode waveguide arrays of sequencing and for BACs using just one SMRT Cell. Long repeat regions can be successfully resolved with this workflow. We also describe a consensus algorithm that incorporates SMRT sequencing primary quality values to produce de novo genome sequence exceeding 99.999% accuracy.
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15
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Assembling Genomes and Mini-metagenomes from Highly Chimeric Reads. LECTURE NOTES IN COMPUTER SCIENCE 2013. [DOI: 10.1007/978-3-642-37195-0_13] [Citation(s) in RCA: 341] [Impact Index Per Article: 31.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
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16
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Gliding motility and Por secretion system genes are widespread among members of the phylum bacteroidetes. J Bacteriol 2012; 195:270-8. [PMID: 23123910 DOI: 10.1128/jb.01962-12] [Citation(s) in RCA: 205] [Impact Index Per Article: 17.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022] Open
Abstract
The phylum Bacteroidetes is large and diverse, with rapid gliding motility and the ability to digest macromolecules associated with many genera and species. Recently, a novel protein secretion system, the Por secretion system (PorSS), was identified in two members of the phylum, the gliding bacterium Flavobacterium johnsoniae and the nonmotile oral pathogen Porphyromonas gingivalis. The components of the PorSS are not similar in sequence to those of other well-studied bacterial secretion systems. The F. johnsoniae PorSS genes are a subset of the gliding motility genes, suggesting a role for the secretion system in motility. The F. johnsoniae PorSS is needed for assembly of the gliding motility apparatus and for secretion of a chitinase, and the P. gingivalis PorSS is involved in secretion of gingipain protease virulence factors. Comparative analysis of 37 genomes of members of the phylum Bacteroidetes revealed the widespread occurrence of gliding motility genes and PorSS genes. Genes associated with other bacterial protein secretion systems were less common. The results suggest that gliding motility is more common than previously reported. Microscopic observations confirmed that organisms previously described as nonmotile, including Croceibacter atlanticus, "Gramella forsetii," Paludibacter propionicigenes, Riemerella anatipestifer, and Robiginitalea biformata, exhibit gliding motility. Three genes (gldA, gldF, and gldG) that encode an apparent ATP-binding cassette transporter required for F. johnsoniae gliding were absent from two related gliding bacteria, suggesting that the transporter may not be central to gliding motility.
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17
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Draft genome sequence of Pedobacter agri PB92T, which belongs to the family Sphingobacteriaceae. J Bacteriol 2012; 194:3738. [PMID: 22740666 DOI: 10.1128/jb.00627-12] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Strain PB92(T) of Pedobacter agri, which belongs to the family Sphingobacteriaceae, was isolated from soil in the Republic of Korea. The draft genome of strain PB92(T) contains 5,141,552 bp, with a G+C content of 38.0%. This is the third genome sequencing project of the type strains among the Pedobacter species.
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18
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Fuerst JA, Sagulenko E. Keys to eukaryality: planctomycetes and ancestral evolution of cellular complexity. Front Microbiol 2012; 3:167. [PMID: 22586422 PMCID: PMC3343278 DOI: 10.3389/fmicb.2012.00167] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2012] [Accepted: 04/13/2012] [Indexed: 12/26/2022] Open
Abstract
Planctomycetes are known to display compartmentalization via internal membranes, thus resembling eukaryotes. Significantly, the planctomycete Gemmata obscuriglobus has not only a nuclear region surrounded by a double-membrane, but is also capable of protein uptake via endocytosis. In order to clearly analyze implications for homology of their characters with eukaryotes, a correct understanding of planctomycete structure is an essential starting point. Here we outline the major features of such structure necessary for assessing the case for or against homology with eukaryote cell complexity. We consider an evolutionary model for cell organization involving reductive evolution of Planctomycetes from a complex proto-eukaryote-like last universal common ancestor, and evaluate alternative models for origins of the unique planctomycete cell plan. Overall, the structural and molecular evidence is not consistent with convergent evolution of eukaryote-like features in a bacterium and favors a homologous relationship of Planctomycetes and eukaryotes.
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Affiliation(s)
- John A Fuerst
- School of Chemistry and Molecular Biosciences, The University of Queensland St Lucia, QLD, Australia
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19
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Tripathi CKM, Banga J, Mishra V. Microbial heparin/heparan sulphate lyases: potential and applications. Appl Microbiol Biotechnol 2012; 94:307-21. [DOI: 10.1007/s00253-012-3967-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2011] [Revised: 12/30/2011] [Accepted: 01/02/2012] [Indexed: 10/28/2022]
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20
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Liolios K, Sikorski J, Lu M, Nolan M, Lapidus A, Lucas S, Hammon N, Deshpande S, Cheng JF, Tapia R, Han C, Goodwin L, Pitluck S, Huntemann M, Ivanova N, Pagani I, Mavromatis K, Ovchinikova G, Pati A, Chen A, Palaniappan K, Land M, Hauser L, Brambilla EM, Kotsyurbenko O, Rohde M, Tindall BJ, Abt B, Göker M, Detter JC, Woyke T, Bristow J, Eisen JA, Markowitz V, Hugenholtz P, Klenk HP, Kyrpides NC. Complete genome sequence of the gliding, heparinolytic Pedobacter saltans type strain (113). Stand Genomic Sci 2011; 5:30-40. [PMID: 22180808 PMCID: PMC3236043 DOI: 10.4056/sigs.2154937] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023] Open
Abstract
Pedobacter saltans Steyn et al. 1998 is one of currently 32 species in the genus Pedobacter within the family Sphingobacteriaceae. The species is of interest for its isolated location in the tree of life. Like other members of the genus P. saltans is heparinolytic. Cells of P. saltans show a peculiar gliding, dancing motility and can be distinguished from other Pedobacter strains by their ability to utilize glycerol and the inability to assimilate D-cellobiose. The genome presented here is only the second completed genome sequence of a type strain from a member of the family Sphingobacteriaceae to be published. The 4,635,236 bp long genome with its 3,854 protein-coding and 67 RNA genes consists of one chromosome, and is a part of the Genomic Encyclopedia of Bacteria and Archaea project.
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Thomas F, Hehemann JH, Rebuffet E, Czjzek M, Michel G. Environmental and gut bacteroidetes: the food connection. Front Microbiol 2011; 2:93. [PMID: 21747801 PMCID: PMC3129010 DOI: 10.3389/fmicb.2011.00093] [Citation(s) in RCA: 655] [Impact Index Per Article: 50.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2011] [Accepted: 04/14/2011] [Indexed: 12/21/2022] Open
Abstract
Members of the diverse bacterial phylum Bacteroidetes have colonized virtually all types of habitats on Earth. They are among the major members of the microbiota of animals, especially in the gastrointestinal tract, can act as pathogens and are frequently found in soils, oceans and freshwater. In these contrasting ecological niches, Bacteroidetes are increasingly regarded as specialists for the degradation of high molecular weight organic matter, i.e., proteins and carbohydrates. This review presents the current knowledge on the role and mechanisms of polysaccharide degradation by Bacteroidetes in their respective habitats. The recent sequencing of Bacteroidetes genomes confirms the presence of numerous carbohydrate-active enzymes covering a large spectrum of substrates from plant, algal, and animal origin. Comparative genomics reveal specific Polysaccharide Utilization Loci shared between distantly related members of the phylum, either in environmental or gut-associated species. Moreover, Bacteroidetes genomes appear to be highly plastic and frequently reorganized through genetic rearrangements, gene duplications and lateral gene transfers (LGT), a feature that could have driven their adaptation to distinct ecological niches. Evidence is accumulating that the nature of the diet shapes the composition of the intestinal microbiota. We address the potential links between gut and environmental bacteria through food consumption. LGT can provide gut bacteria with original sets of utensils to degrade otherwise refractory substrates found in the diet. A more complete understanding of the genetic gateways between food-associated environmental species and intestinal microbial communities sheds new light on the origin and evolution of Bacteroidetes as animals’ symbionts. It also raises the question as to how the consumption of increasingly hygienic and processed food deprives our microbiota from useful environmental genes and possibly affects our health.
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Affiliation(s)
- François Thomas
- UMR 7139, Marine Plants and Biomolecules, Station Biologique de Roscoff, UPMC University Paris 6, Roscoff, France
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22
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Abstract
Carbohydrate-active enzymes face huge substrate diversity in a highly selective manner using only a limited number of available folds. They are therefore subjected to multiple divergent and convergent evolutionary events. This and their frequent modularity render their functional annotation in genomes difficult in a number of cases. In the present paper, a classification of polysaccharide lyases (the enzymes that cleave polysaccharides using an elimination instead of a hydrolytic mechanism) is shown thoroughly for the first time. Based on the analysis of a large panel of experimentally characterized polysaccharide lyases, we examined the correlation of various enzyme properties with the three levels of the classification: fold, family and subfamily. The resulting hierarchical classification, which should help annotate relevant genes in genomic efforts, is available and constantly updated at the Carbohydrate-Active Enzymes Database (http://www.cazy.org).
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An algorithm for automated closure during assembly. BMC Bioinformatics 2010; 11:457. [PMID: 20831800 PMCID: PMC2945939 DOI: 10.1186/1471-2105-11-457] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2010] [Accepted: 09/10/2010] [Indexed: 01/15/2023] Open
Abstract
Background Finishing is the process of improving the quality and utility of draft genome sequences generated by shotgun sequencing and computational assembly. Finishing can involve targeted sequencing. Finishing reads may be incorporated by manual or automated means. One automated method uses targeted addition by local re-assembly of gap regions. An obvious alternative uses de novo assembly of all the reads. Results A procedure called the bounding read algorithm was developed for assembly of shotgun reads plus finishing reads and their constraints, targeting repeat regions. The algorithm was implemented within the Celera Assembler software and its pyrosequencing-specific variant, CABOG. The implementation was tested on Sanger and pyrosequencing data from six genomes. The bounding read assemblies were compared to assemblies from two other methods on the same data. The algorithm generates improved assemblies of repeat regions, closing and tiling some gaps while degrading none. Conclusions The algorithm is useful for small-genome automated finishing projects. Our implementation is available as open-source from http://wgs-assembler.sourceforge.net under the GNU Public License.
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