Comparative Genomics of Syntrophic Branched-Chain Fatty Acid Degrading Bacteria

• Narihiro Takashi

  Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST) Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign

• Nobu Masaru K.

  Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign

• Tamaki Hideyuki

  Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST) Biotechnology Research Institute, The University of Tokyo

• Kamagata Yoichi

  Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology (AIST)

• Sekiguchi Yuji

  Biomedical Research Institute, National Institute of Advanced Industrial Science and Technology (AIST)

• Liu Wen-Tso

  Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign

抄録

The syntrophic degradation of branched-chain fatty acids (BCFAs) such as 2-methylbutyrate and isobutyrate is an essential step in the production of methane from proteins/amino acids in anaerobic ecosystems. While a few syntrophic BCFA-degrading bacteria have been isolated, their metabolic pathways in BCFA and short-chain fatty acid (SCFA) degradation as well as energy conservation systems remain unclear. In an attempt to identify these pathways, we herein performed comparative genomics of three syntrophic bacteria: 2-methylbutyrate-degrading “Syntrophomonas wolfei subsp. methylbutyratica” strain JCM 14075^T (=4J5^T), isobutyrate-degrading Syntrophothermus lipocalidus strain TGB-C1^T, and non-BCFA-metabolizing S. wolfei subsp. wolfei strain Göttingen^T. We demonstrated that 4J5 and TGB-C1 both encode multiple genes/gene clusters involved in β-oxidation, as observed in the Göttingen genome, which has multiple copies of genes associated with butyrate degradation. The 4J5 genome possesses phylogenetically distinct β-oxidation genes, which may be involved in 2-methylbutyrate degradation. In addition, these Syntrophomonadaceae strains harbor various hydrogen/formate generation systems (i.e., electron-bifurcating hydrogenase, formate dehydrogenase, and membrane-bound hydrogenase) and energy-conserving electron transport systems, including electron transfer flavoprotein (ETF)-linked acyl-CoA dehydrogenase, ETF-linked iron-sulfur binding reductase, ETF dehydrogenase (FixABCX), and flavin oxidoreductase-heterodisulfide reductase (Flox-Hdr). Unexpectedly, the TGB-C1 genome encodes a nitrogenase complex, which may function as an alternative H₂ generation mechanism. These results suggest that the BCFA-degrading syntrophic strains 4J5 and TGB-C1 possess specific β-oxidation-related enzymes for BCFA oxidation as well as appropriate energy conservation systems to perform thermodynamically unfavorable syntrophic metabolism.

収録刊行物

• Ｍｉｃｒｏｂｅｓ　ａｎｄ　ｅｎｖｉｒｏｎｍｅｎｔｓ

  Ｍｉｃｒｏｂｅｓ　ａｎｄ　ｅｎｖｉｒｏｎｍｅｎｔｓ 31 (3), 288-292, 2016

  日本微生物生態学会 / 日本土壌微生物学会 / Taiwan Society of Microbial Ecology / 植物微生物研究会 / 極限環境微生物学会

キーワード

• syntroph
• branched-chain fatty acid
• genomics
• energy conservation

詳細情報

• CRID: 1390282679321916800
• NII論文ID: 40020943119
• NII論文ID: 130005265098
• NII書誌ID: AA11551577
• DOI: 10.1264/jsme2.me16057
• ISSN: 13474405
• ISSN: 13426311
• NDL書誌ID: 027619141
• PubMed: 27431485
• Web Site: https://ndlsearch.ndl.go.jp/books/R000000004-I027619141
• Web Site: https://www.jstage.jst.go.jp/article/jsme2/31/3/31_ME16057/_pdf
• 本文言語コード: en
• データソース種別:
  • JaLC
  • NDL
  • Crossref
  • PubMed
  • CiNii Articles
  • KAKEN
• 抄録ライセンスフラグ: 使用不可