Humic acid-dependent respiratory growth of Methanosarcina acetivorans involves pyrroloquinoline quinone.

ABSTRACT: Although microbial humus respiration plays a critical role in organic matter decomposition and biogeochemical cycling of elements in diverse anoxic environments, the role of methane-producing species (methanogens) is not well defined. Here we report that a major fraction of humus, humic acid reduction enhanced the growth of Methanosarcina acetivorans above that attributed to methanogenesis when utilizing the energy sources methanol or acetate, results which showed both respiratory and fermentative modes of energy conservation. Growth characteristics with methanol were the same for an identically cultured mutant deleted for the gene encoding a multi-heme cytochrome c (MmcA), results indicating MmcA is not essential for respiratory electron transport to humic acid. Transcriptomic analyses re

SUBMITTER: Song Y 

PROVIDER: S-EPMC10579383 | biostudies-literature | 2023 Nov

REPOSITORIES: biostudies-literature