Physiological and transcriptomic analyses of the thermophilic, aceticlastic methanogen Methanosaeta thermophila responding to ammonia stress.

ABSTRACT: The inhibitory effects of ammonia on two different degradation pathways of methanogenic acetate were evaluated using a pure culture (Methanosaeta thermophila strain PT) and defined co-culture (Methanothermobacter thermautotrophicus strain TM and Thermacetogenium phaeum strain PB), which represented aceticlastic and syntrophic methanogenesis, respectively. Growth experiments with high concentrations of ammonia clearly demonstrated that sensitivity to ammonia stress was markedly higher in M. thermophila PT than in the syntrophic co-culture. M. thermophila PT also exhibited higher sensitivity to high pH stress, which indicated that an inability to maintain pH homeostasis is an underlying cause of ammonia inhibition. Methanogenesis was inhibited in the resting cells of M. thermophila PT with m

SUBMITTER: Kato S 

PROVIDER: S-EPMC4103522 | biostudies-literature | 2014

REPOSITORIES: biostudies-literature