Methanosarcina barkeri

About: Methanosarcina barkeri is a research topic. Over the lifetime, 703 publications have been published within this topic receiving 32151 citations.

Methanogenesis from monomethylamine : biochemical and molecular characterization of the monomethylamine:coenzyme m methyl transfer activity in Methanosarcina barkeri /

Abstract: Methanogens produce methane from a limited number of simple compounds such as CO2 with H2, acetate, methanol, methylthiols, and methylated amines. The well studied pathways of methane formation from CO2, acetate, and methanol have revealed that methanogenesis from each of these substrates requires the intermediate méthylation of 2 mercaptoethanesulfonate (CoM). Methanogenesis from methylated amines also requires the intermediate méthylation of CoM, however, the enzymes which mediate this process are still largely uncharacterized. Therefore, this study was undertaken to isolate and characterize the enzymes catalyzing the méthylation of CoM with monomethylamine (MMA), to reconstitute this reaction in vitro with purified proteins, clone and sequence the genes encoding these enzymes, and analyze their transcripts. Méthylation of CoM with MMA requires three proteins: a 170-kDa protein composed of 52-kDa subunits termed MMAMT, a 29-kDa corrinoidbinding protein designated MMCP, and the "A" isozyme of methylcobamideiCoM methyltransferase (MT2-A). Méthylation of CoM with MMA was reconstituted in vitro with the purified proteins and the catalytic roles of each component of the enzyme system were directly demonstrated. CoM is methylated indirectly in two steps. First, MMAMT catalyzes the

Production of formic acid

Abstract: PURPOSE:To produce formic acid easily and economically by biochemical means, by reacting carbon monoxide with water in the presence of a cultured liquid, cultured cells or treated cells of microorganism belonging to Methanosarcina genus CONSTITUTION:A microbial strain belonging to Methanosarcina genus and capable of producing methane, eg Methanosarcina barkeri, etc, is cultured under anaerobic condition, and the cultured liquid, microbial cells separated from the cultured liquid, or treated microbial cells are collected The obtained cells or treated cells, etc, may be used in immobilized state Carbon monoxide is made to react with water under anaerobic condition in the presence of the microbial cells in a reaction liquid added with an electron acceptor such as methyl viologen to obtain formic acid The produced formic acid is separated and purified by conventional extraction process

Uni- and Dicarbon Metabolism of Methanosarcina Barkeri Strain Ms in Defined Medium

Abstract: The contributions of C-2 and C-1 labelled acetate to CH4 and CO2 were examined in acetate adapted culture of Methanosarcina barkeri grown in mineral medium The methyl group of acetate accounted for the majority of CH4 produced; however, 15% of the C-2 of acetate was oxidized to 14CO2 This oxidation correlated with the concurrent reduction of the carboxyl group 14CH4 was produced from 14C-1 acetate in amounts slightly less than the values detected for 14C-2 acetate conversion to CO2 Acetate adapted cells were capable of simultaneous metabolism of both methanol and acetate during growth in a medium that contained 50 mM of each substrate The rate of 14CH4 generation from 14C-2 acetate was logrithmic and faster than that observed during unitrophic growth on acetate The rate of 14CO2 production from 14C-2 acetate was twice that of unitrophic cultures After methanol depletion the rate of 14CH4 production remained unchanged, while 14CO2 production decreased two-fold In mixotrophic growth studies with 120 mM methanol and 50 mM acetate the rate of 14CH2 production from 14C-2 acetate decreased several fold over that observed in unitrophic or in the equal (substrate) mixotrophic cultures However, μ CH4 decreased 2-fold which suggests that methanol toxcity was the cause of this effect

Online Parameter Identification and Computer Control of an Anaerobic Waste Water Treatment Process

Abstract: Anaerobic waste water treatment becomes more and more important since the space-time yield of the processes has been rapidly increased by biomass retention techniques. In our system the microorganisms are fixed on open-pore sintered glass. The bacterial culture is a mixed culture of Methanosarcina barkeri, Desulfovibrio gigas and others /Aivasidis, 1985/.