A methyl‐CoM methylreductase system from methanogenic bacterium strain Göl not requiring ATP for activity

FEBS Letters

Blaut, M.¹  Jussofie, A.¹  Deppenmeier, U.¹  Gottschalk, G.¹ 

[1] Institut für Mikrobiologie, Grisebachstr. 8, D-3400 Göttingen, FRG

关键词: Methane formation;    Methyl-CoM methylreductase;    Hydrogenase;    (Methanogenic bacteria);    Na-CoM;    sodium 2-mercaptoethane sulfonate;    F420;    the (N-L-lactyl-γ-L-glutamyl)-L-glutamic acid phosphodiester of 7;    8-didemethyl-8-hydroxy-5-deazariboflavin-5′-phosphate;    methyl-CoM;    methyl coenzyme M;    β;    γ-methylene-ATP;    adenylyl-(β;    γ-methylene)diphosphate;    β;    γ-imido-ATP;    adenylyl-(β;    γ-imido)-diphosphate;    diadenosine-P5;    P1;    P5'-di-(adenosine-5′-)pentaphosphate;    dial-ATP;    adenosine 5′-triphosphate-2′;    3′-dialdehyde;    DTE;    dithioerythritol;    PMSF;    phenylmethanesulfonyl fluoride;    sulfobetaine;    N-tetradecyl-N;    N-dimethylammonio-3-propanesulfonate;    HS-HTP;    7-mercaptoheptanoylthreonine phosphate;   

DOI  :  10.1016/0014-5793(88)81031-7

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Crude inside-out vesicles from the methanogenic strain Göl were prepared via protoplasts. These vesicles catalysed methane formation from methyl-CoM and H₂ at a maximal rate of 35 nmol/min · mg protein. Methane formation by the vesicles did not depend on the addition of ATP. This was in contrast to conventionally prepared crude extracts from the same organism or from Methanosarcina barkeri which exhibited strict ATP dependence of methanogenesis. ATP analogues inhibited methanogenesis by extracts to a much higher extent than that by vesicles. Both, particulate and soluble components prepared from the crude vesicles by ultracentrifugation were necessary for ATP-independent methane formation from methyl-CoM and H₂. Hydrogenase activity was mainly associated with the particulate fraction whereas methyl-CoM methylreductase could be assigned to the soluble fraction. The detergent sulfobetaine inhibited methane formation from methyl-CoM without affecting hydrogenase or titanium citrate-dependent methylreductase activities, indicating that an additional membraneous component is involved in methanogenesis for methyl-CoM and H₂.

【 授权许可】

Unknown