Open AccessIsolation and characterization of an uncoupler‐resistant mutant of Methanothermobacter thermautotrophicus
Author(s) -
Čuboňová L'ubomı́ra,
Šurı́n Stanislav,
Majernı́k Alan,
Šmigáň Peter
Publication year - 2004
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 - 10.1016/j.femsle.2004.01.033
Subject(s) - mutant , biochemistry , atpase , strain (injury) , biology , chemistry , enzyme , gene , anatomy
A spontaneous mutant of Methanothermobacter thermautotrophicus resistant to the protonophorous uncoupler TCS was isolated. The mutant strain exhibited increased CH 4 formation and elevated level of ATPase activity under non‐growing conditions. ATP synthesis driven by methanogenic electron transport as well as by potassium diffusion potential in the presence of either H + or Na + ions was markedly diminished in the mutant strain. An abundant membrane‐associated protein complex with molecular mass approximately 670 kDa was detected in the mutant strain after native PAGE. The results indicate that TCS resistance in this mutant has arisen as a consequence of mutation(s) that affects a specific locus coding for an uncoupler binding protein(s) and/or modulate the activity of unidentified ATPase.