Transport of coenzyme M (2-mercaptoethanesulfonic acid) in Methanobacterium ruminantium
- 1 January 1979
- journal article
- research article
- Published by American Society for Microbiology in Journal of Bacteriology
- Vol. 137 (1), 264-273
- https://doi.org/10.1128/jb.137.1.264-273.1979
Abstract
A system for transport of coenzyme M, 2-mercaptoethanesulfonic acid (HS-CoM), in M. ruminantium strain M1 required energy, showed saturation kinetics, and concentrated the coenzyme against a gradient. The process was sensitive to temperature and was maximally active at pH 7.1. Cells took up HS-CoM at a linear rate, with a Vmax of 312 pmol/min per mg (dry wt) and an apparent Km of 73 nM. An intracellular pool of up to 5 mM accumulated which was not exchangeable with the medium. Uptake required H2 and CO2; it was inhibited by O2. Bromoethanesulfonic acid (BrCH2CH2SO3-), a potent inhibitor of methanogenesis in cell-free extracts, inhibited uptake and methane production. Results of inhibitor studies with derivatives and analogs of the coenzyme showed that the specificity of the carrier is restricted to a limited range of thioether, thioester and thiocarbonate derivatives. 2-(Methylthio)ethanesulfonic acid (CH3-S-CoM) showed an apparent Ki [inhibition constant] for HS-CoM uptake of 15 nM, being taken up itself with a vmax of 320 pmol/min per mg (dry wt) and an apparent Km of 50 nM. An analysis of intracellular pools after HS-CoM uptake indicated that the predominant forms are a heterodisulfide of unknown composition and CH3-S-CoM.This publication has 20 references indexed in Scilit:
- Preparation of coenzyme M analogs and their activity in the methyl coenzyme M reductase system of Methanobacterium thermoautotrophicumBiochemistry, 1978
- Transport and metabolism of vitamin B6 in lactic acid bacteria.Journal of Biological Chemistry, 1977
- Transport and metabolism of vitamin B6 in the yeast Saccharomyces carlsbergensis 4228.Journal of Biological Chemistry, 1976
- Transport and metabolism of vitamin B6 in Salmonella typhimurium LT2.Journal of Biological Chemistry, 1976
- Transport and metabolism of folates by bacteria.Journal of Biological Chemistry, 1975
- Structure and Methylation of Coenzyme M (HSCH2CH2SO3)Journal of Biological Chemistry, 1974
- Transport of vitamin B 12 in Escherichia coli.1971
- A simple efficient liquid scintillator for counting aqueous solutions in a liquid scintillation counterAnalytical Biochemistry, 1960
- A colorimetric method for determining low concentrations of mercaptansArchives of Biochemistry and Biophysics, 1958