Phylogenetic diversity of methyl-coenzyme M reductase (mcrA) gene and methanogenesis from trimethylamine in hypersaline environments.

摘要: Methanogens have been reported in complex microbial communities from hypersaline environments, but little is known about their phylogenetic diversity. In this work, methane concentrations environmental gas samples were determined while production rates measured microcosm experiments with competitive and non-competitive substrates. In addition, the diversity of methanogens mats two geographical locations was analyzed: the well studied Guerrero Negro ecosystem, a site not previously investigated, namely Laguna San Ignacio, Baja California Sur, Mexico. Methanogenesis these suspected based on detection of methane (in range 0.00086 to 3.204 %) samples. Microcosm confirmed production by demonstrated that it promoted only by substrates (trimethylamine and methanol), suggesting methylotrophy main characteristic process which produce methane. Phylogenetic analysis amino acid sequences methyl coenzyme-M reductase (mcrA) gene natural and manipulated revealed various methylotrophic belonging exclusively family Methanosarcinaceae. Moderately halophilic microorganisms genus Methanohalophilus predominant (>60 % of mcrA retrieved). Slightly marine genera Methanococcoides and Methanolobus, respectively, also identified, lower abundances. [Int Microbiol 2012; 15(1):33-41]