Tributyltin-resistant Methanothermobacter thermautotrophicus mutant with mutational substitutions in the A1A0-ATP synthase operon.
A spontaneous mutant of Methanothermobacter thermautotrophicus resistant to tributyltin chloride (TBT) was isolated. TBT, the inhibitor of the A(0) domain of A(1)A(0)-ATP synthase, inhibits methanogenesis in the wild-type cells; however, the TBT-resistant mutant exhibited methanogenesis even in the presence of 800 microM TBT. ATP synthesis driven by methanogenic electron transport was markedly diminished in the mutant strain. While TBT profoundly inhibited ATP synthesis driven by methanogenic electron transport in the wild type, only a slight inhibition was observed in the mutant strain. These results suggested a modification in the ATP-synthesizing system of the mutant strain. The sequence of the complete A(1)A(0)-ATP synthase operon (Mth952-Mth961) in the wild-type and mutant strains was determined and compared. Three mutations leading to amino acid substitutions in two A(1)A(0)-ATP synthase subunits were identified - Val(338)Ala in subunit A and Leu(252)Ile and Ser(293)Ala in subunit B. Moreover, this study revealed the differential expression of several proteins that may contribute to TBT resistance. The results imply that change of TBT sensitivities of TBT-resistant mutant is due to mutational substitutions in the A(1)A(0)-ATP synthase operon.
Nováková
Zuzana
Z
Institute of Animal Biochemistry and Genetics, Slovak Academy of Sciences, Ivanka pri Dunaji, Slovak Republic.
Bobálová
Janette
J
Vidová
Monika
M
Hapala
Ivan
I
Smigán
Peter
P
D025181:ATP Synthetase Complexes / Q000235:genetics*; D000255:Adenosine Triphosphate / Q000096:biosynthesis; D019943:Amino Acid Substitution / Q000235:genetics*; D000890:Anti-Infective Agents / Q000494:pharmacology*; D004252:DNA Mutational Analysis; D019641:DNA, Archaeal / Q000737:chemistry / Q000235:genetics; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D008697:Methane / Q000378:metabolism; D017013:Methanobacteriaceae / Q000187:drug effects*; D020125:Mutation, Missense; D017422:Sequence Analysis, DNA; D014220:Trialkyltin Compounds / Q000494:pharmacology*
D000890:Anti-Infective Agents; D019641:DNA, Archaeal; D004791:Enzyme Inhibitors; D014220:Trialkyltin Compounds; C011559:tributyltin; D000255:Adenosine Triphosphate; D025181:ATP Synthetase Complexes; D008697:Methane