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ATP synthesis coupled to electron transfer from H 2 to the heterodisulfide of 2‐mercaptoethanesulfonate and 7‐mercaptoheptanoylthreonine phosphate in vesicle preparations of the methanogenic bacterium strain Gö1
Author(s) -
Peinemann S.,
Hedderich R.,
Blaut M.,
Thauer R.K.,
Gottschalk G.
Publication year - 1990
Publication title -
febs letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.593
H-Index - 257
eISSN - 1873-3468
pISSN - 0014-5793
DOI - 10.1016/0014-5793(90)80704-m
Subject(s) - atp synthase , chemiosmosis , electron transport chain , methanogenesis , chemistry , electrochemical gradient , biochemistry , n ethylmaleimide , electron transfer , stereochemistry , bacteria , adenosine triphosphate , enzyme , biology , organic chemistry , membrane , genetics
Crude vesicle preparations of the methanogenic strain Gol were able to couple the reduction of the heterodisulfide of 2‐mercaptoethanesulfonate and 7‐mercaptoheptanoylthreonine phosphate (CoM‐ S ‐ S ‐HTP) by H 2 with ATP formation. The rate of ATP synthesis was 1mg protein. ATP synthesis and disulfide reduction were only observed with CoM‐ S ‐ S ‐HTP, but not with CoM‐ S ‐ S ‐CoM or HTP‐ S ‐ S ‐HTP. The methylreductase inhibitor 2‐bromoethanesulfonic acid had no effect on ATP synthesis induced by CoM‐ S ‐ S ‐HTP reduction with H 2 . ATP synthesis was completely inhibited by the uncoupler SF 6847 whereas the concomitant CoM‐ S ‐ S ‐HTP reduction was stimulated. The ATP synthase inhibitors DCCD and DES also inhibited ATP formation completely and decreased the CoM‐ S ‐ S ‐HTP reduction rate to 35% of the control. These inhibitory effects were abolished by addition of the uncoupler. From these results it is concluded that energy coupling between the electron transfer from H 2 to the heterodisulfide and ATP synthesis occurs via a transmembrane proton gradient.