Energy Conservation and Hydrogenase Function in Methanogenic Archaea, in Particular the Genus Methanosarcina

Thomas D. Mand, William W Metcalf

Research output: Contribution to journalReview article

Abstract

SUMMARYThe biological production of methane is vital to the global carbon cycle and accounts for ca. 74% of total methane emissions. The organisms that facilitate this process, methanogenic archaea, belong to a large and phylogenetically diverse group that thrives in a wide range of anaerobic environments. Two main subgroups exist within methanogenic archaea: those with and those without cytochromes. Although a variety of metabolisms exist within this group, the reduction of growth substrates to methane using electrons from molecular hydrogen is, in a phylogenetic sense, the most widespread methanogenic pathway. Methanogens without cytochromes typically generate methane by the reduction of CO2 with electrons derived from H2, formate, or secondary alcohols, generating a transmembrane ion gradient for ATP production via an Na+-translocating methyltransferase (Mtr). These organisms also conserve energy with a novel flavin-based electron bifurcation mechanism, wherein the endergonic reduction of ferredoxin is facilitated by the exergonic reduction of a disulfide terminal electron acceptor coupled to either H2 or formate oxidation. Methanogens that utilize cytochromes have a broader substrate range, and can convert acetate and methylated compounds to methane, in addition to the ability to reduce CO2 Cytochrome-containing methanogens are able to supplement the ion motive force generated by Mtr with an H+-translocating electron transport system. In both groups, enzymes known as hydrogenases, which reversibly interconvert protons and electrons to molecular hydrogen, play a central role in the methanogenic process. This review discusses recent insight into methanogen metabolism and energy conservation mechanisms with a particular focus on the genus Methanosarcina.

Original languageEnglish (US)
JournalMicrobiology and molecular biology reviews : MMBR
Volume83
Issue number4
DOIs
StatePublished - Nov 20 2019

Fingerprint

Methanosarcina
Hydrogenase
Archaea
Methane
formic acid
Cytochromes
Electrons
Methyltransferases
Hydrogen
Ions
Carbon Cycle
Ferredoxins
Electron Transport
Disulfides
Energy Metabolism
Protons
Acetates
Adenosine Triphosphate
Alcohols
Enzymes

Keywords

  • Archaea
  • energy conservation
  • hydrogenase
  • methanogenesis

ASJC Scopus subject areas

  • Microbiology
  • Molecular Biology
  • Immunology and Microbiology(all)
  • Infectious Diseases

Cite this

@article{615515bfea7b4091afbf257cb49aab47,
title = "Energy Conservation and Hydrogenase Function in Methanogenic Archaea, in Particular the Genus Methanosarcina",
abstract = "SUMMARYThe biological production of methane is vital to the global carbon cycle and accounts for ca. 74{\%} of total methane emissions. The organisms that facilitate this process, methanogenic archaea, belong to a large and phylogenetically diverse group that thrives in a wide range of anaerobic environments. Two main subgroups exist within methanogenic archaea: those with and those without cytochromes. Although a variety of metabolisms exist within this group, the reduction of growth substrates to methane using electrons from molecular hydrogen is, in a phylogenetic sense, the most widespread methanogenic pathway. Methanogens without cytochromes typically generate methane by the reduction of CO2 with electrons derived from H2, formate, or secondary alcohols, generating a transmembrane ion gradient for ATP production via an Na+-translocating methyltransferase (Mtr). These organisms also conserve energy with a novel flavin-based electron bifurcation mechanism, wherein the endergonic reduction of ferredoxin is facilitated by the exergonic reduction of a disulfide terminal electron acceptor coupled to either H2 or formate oxidation. Methanogens that utilize cytochromes have a broader substrate range, and can convert acetate and methylated compounds to methane, in addition to the ability to reduce CO2 Cytochrome-containing methanogens are able to supplement the ion motive force generated by Mtr with an H+-translocating electron transport system. In both groups, enzymes known as hydrogenases, which reversibly interconvert protons and electrons to molecular hydrogen, play a central role in the methanogenic process. This review discusses recent insight into methanogen metabolism and energy conservation mechanisms with a particular focus on the genus Methanosarcina.",
keywords = "Archaea, energy conservation, hydrogenase, methanogenesis",
author = "Mand, {Thomas D.} and Metcalf, {William W}",
year = "2019",
month = "11",
day = "20",
doi = "10.1128/MMBR.00020-19",
language = "English (US)",
volume = "83",
journal = "Microbiology and Molecular Biology Reviews",
issn = "1092-2172",
publisher = "American Society for Microbiology",
number = "4",

}

TY - JOUR

T1 - Energy Conservation and Hydrogenase Function in Methanogenic Archaea, in Particular the Genus Methanosarcina

AU - Mand, Thomas D.

AU - Metcalf, William W

PY - 2019/11/20

Y1 - 2019/11/20

N2 - SUMMARYThe biological production of methane is vital to the global carbon cycle and accounts for ca. 74% of total methane emissions. The organisms that facilitate this process, methanogenic archaea, belong to a large and phylogenetically diverse group that thrives in a wide range of anaerobic environments. Two main subgroups exist within methanogenic archaea: those with and those without cytochromes. Although a variety of metabolisms exist within this group, the reduction of growth substrates to methane using electrons from molecular hydrogen is, in a phylogenetic sense, the most widespread methanogenic pathway. Methanogens without cytochromes typically generate methane by the reduction of CO2 with electrons derived from H2, formate, or secondary alcohols, generating a transmembrane ion gradient for ATP production via an Na+-translocating methyltransferase (Mtr). These organisms also conserve energy with a novel flavin-based electron bifurcation mechanism, wherein the endergonic reduction of ferredoxin is facilitated by the exergonic reduction of a disulfide terminal electron acceptor coupled to either H2 or formate oxidation. Methanogens that utilize cytochromes have a broader substrate range, and can convert acetate and methylated compounds to methane, in addition to the ability to reduce CO2 Cytochrome-containing methanogens are able to supplement the ion motive force generated by Mtr with an H+-translocating electron transport system. In both groups, enzymes known as hydrogenases, which reversibly interconvert protons and electrons to molecular hydrogen, play a central role in the methanogenic process. This review discusses recent insight into methanogen metabolism and energy conservation mechanisms with a particular focus on the genus Methanosarcina.

AB - SUMMARYThe biological production of methane is vital to the global carbon cycle and accounts for ca. 74% of total methane emissions. The organisms that facilitate this process, methanogenic archaea, belong to a large and phylogenetically diverse group that thrives in a wide range of anaerobic environments. Two main subgroups exist within methanogenic archaea: those with and those without cytochromes. Although a variety of metabolisms exist within this group, the reduction of growth substrates to methane using electrons from molecular hydrogen is, in a phylogenetic sense, the most widespread methanogenic pathway. Methanogens without cytochromes typically generate methane by the reduction of CO2 with electrons derived from H2, formate, or secondary alcohols, generating a transmembrane ion gradient for ATP production via an Na+-translocating methyltransferase (Mtr). These organisms also conserve energy with a novel flavin-based electron bifurcation mechanism, wherein the endergonic reduction of ferredoxin is facilitated by the exergonic reduction of a disulfide terminal electron acceptor coupled to either H2 or formate oxidation. Methanogens that utilize cytochromes have a broader substrate range, and can convert acetate and methylated compounds to methane, in addition to the ability to reduce CO2 Cytochrome-containing methanogens are able to supplement the ion motive force generated by Mtr with an H+-translocating electron transport system. In both groups, enzymes known as hydrogenases, which reversibly interconvert protons and electrons to molecular hydrogen, play a central role in the methanogenic process. This review discusses recent insight into methanogen metabolism and energy conservation mechanisms with a particular focus on the genus Methanosarcina.

KW - Archaea

KW - energy conservation

KW - hydrogenase

KW - methanogenesis

UR - http://www.scopus.com/inward/record.url?scp=85072394483&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85072394483&partnerID=8YFLogxK

U2 - 10.1128/MMBR.00020-19

DO - 10.1128/MMBR.00020-19

M3 - Review article

C2 - 31533962

AN - SCOPUS:85072394483

VL - 83

JO - Microbiology and Molecular Biology Reviews

JF - Microbiology and Molecular Biology Reviews

SN - 1092-2172

IS - 4

ER -