A mutation altering the kinetic responses of the yeast mitochondrial F1-ATPase.
Nucleotide-binding proteins, including the mitochondrial F1-ATPase, the ras proteins, and the G-proteins, contain a homologous glycine-rich sequence that is thought to constitute part of the active site. This study reports the effects of a single amino acid replacement of Thr197 to Ser197, which is located at the hinge region of this putative loop, in the yeast Saccharomyces cerevisiae F1-ATPase. This replacement resulted in a 3-fold increase in the specific activity of the enzyme, eliminated the stimulatory effects of oxyanions, and modulated the effects of the inhibitor NaN3 while having little effect on the uni-site ATPase. These results indicate a role of the glycine-rich loop in many of the kinetic responses of the F1-ATPase.
Mueller
D M
DM
Department of Biological Chemistry and Structure, Chicago Medical School, University of Health Sciences, Illinois 60064.
D000595:Amino Acid Sequence; D001483:Base Sequence; D004926:Escherichia coli / Q000235:genetics; D005796:Genes; D005800:Genes, Fungal; D007700:Kinetics; D008969:Molecular Sequence Data; D009154:Mutation; D015345:Oligonucleotide Probes; D006180:Proton-Translocating ATPases / Q000235:genetics / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000201:enzymology* / Q000235:genetics; D012689:Sequence Homology, Nucleic Acid; D014170:Transformation, Genetic
D015345:Oligonucleotide Probes; D006180:Proton-Translocating ATPases