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

"Methanogens have been reported in complex microbial communities from hypersaline environments, but little is known about their phylogenetic diversity. In this work, methane concentrations in environmental gas samples were determined while methane production rates were measured in microcosm exp...

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Detalles Bibliográficos
Autores: JOSE QUINATZIN GARCIA MALDONADO, MARIA DE LOURDES BERENICE CELIS GARCIA, ALEJANDRO LOPEZ CORTES
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2012
País:México
Institución:Instituto Potosino de Investigación Científica y Tecnológica
Repositorio:Repositorio Institucional del IPICYT
Idioma:inglés
OAI Identifier:oai:ipicyt.repositorioinstitucional.mx:1010/1244
Acceso en línea:http://ipicyt.repositorioinstitucional.mx/jspui/handle/1010/1244
Access Level:acceso abierto
Palabra clave:info:eu-repo/classification/Autor/Methanosarcinaceae
info:eu-repo/classification/Autor/Hypersaline environments
info:eu-repo/classification/Autor/Microbial mats
info:eu-repo/classification/Autor/Trimethylamine
info:eu-repo/classification/Autor/Gene mcrA
info:eu-repo/classification/cti/6
Descripción
Sumario:"Methanogens have been reported in complex microbial communities from hypersaline environments, but little is known about their phylogenetic diversity. In this work, methane concentrations in environmental gas samples were determined while methane production rates were measured in microcosm experiments with competitive and non-competitive substrates. In addition, the phylogenetic diversity of methanogens in microbial mats from two geographical locations was analyzed: the well studied Guerrero Negro hypersaline ecosystem, and a site not previously investigated, namely Laguna San Ignacio, Baja California Sur, Mexico. Methanogenesis in these microbial mats was suspected based on the detection of methane (in the range of 0.00086 to 3.204 %) in environmental gas samples. Microcosm experiments confirmed methane production by the mats and demonstrated that it was promoted only by non-competitive substrates (trimethylamine and methanol), suggesting that methylotrophy is the main characteristic process by which these hypersaline microbial mats produce methane. Phylogenetic analysis of amino acid sequences of the methyl coenzyme-M reductase (mcrA) gene from natural and manipulated samples revealed various methylotrophic methanogens belonging exclusively to the family Methanosarcinaceae. Moderately halophilic microorganisms of the genus Methanohalophilus were predominant (>60 % of mcrA sequences retrieved). Slightly halophilic and marine microorganisms of the genera Methanococcoides and Methanolobus, respectively, were also identified, but in lower abundances."