Open AccessAcetate threshold values and acetate activating enzymes in methanogenic bacteria
Author(s) -
Jetten Mike S.M.,
Stams Alfons J.M.,
Zehnder Alexander J.B.
Publication year - 1990
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1990.tb03958.x
Subject(s) - bacteria , chemistry , methanosarcina , methane , anaerobic bacteria , methanogenesis , enzyme , biochemistry , microbiology and biotechnology , food science , biology , organic chemistry , genetics
The minimum threshold concentrations of acetate utilization and the enzymes responsible for acetate activation of several methanogenic bacteria were investigated and compared with literature data. The minimum acetate concentrations reached by hydrogenotrophic methane bacteria, which require acetate as carbon source, were between 0.4 and 0.6 mM. The acetoclastic Methanosarcina achieves acetate concentrations between 0.2 and 1.2 mM and Methanothrix between 7 and 70 μM. For the activation of acetate most of the hydrogenotrophic methane bacteria investigated use an acetyl‐CoA synthetase with a relatively low K m (40–90 μM) for acetate. although the affinity for acetate was high, the hydrogenotrophic methane bacteria were not able to remove acetate to lower concentrations than the acetoclastic methane bacteria, neither in pure cultures nor in anaerobic granular sludge samples. Based on these observations, it is not likely that hydrogenotrophic methanogens compete strongly for acetate with the acetoclastic methane bacteria.