Comparative biochemical studies of ATPases in cells from patients with the T8993G or T8993C mitochondrial DNA mutations.
We performed comparative biochemical studies in cultured fibroblast mitochondria from patients with the T8993G or the T8993C point mutations in the ATPase 6 gene of mitochondrial DNA. We found that ATP production was much more severely decreased in cells from patients with the T8993G mutation than in those from patients with the T8993C mutation. Kinetic studies suggest that both mutations affect only the F0 sector of the mitochondrial ATPase complex. We conclude that these two mutations, which result in the substitution of different amino acids at the same site of the ATPase, result in an enzyme with different biochemical characteristics.
Vázquez-Memije
M E
ME
Unidad de Investigación en Genética Humana, Hospital de Pediatría, Centro Médico Nacional-IMSS, México, D.F.
Shanske
S
S
Santorelli
F M
FM
Kranz-Eble
P
P
DeVivo
D C
DC
DiMauro
S
S
D000251:Adenosine Triphosphatases / Q000235:genetics* / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000096:biosynthesis; D004272:DNA, Mitochondrial / Q000235:genetics*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005347:Fibroblasts / Q000648:ultrastructure; D006801:Humans; D007700:Kinetics; D008928:Mitochondria / Q000201:enzymology; D009840:Oligomycins / Q000494:pharmacology; D010101:Oxygen Consumption; D017354:Point Mutation; D006180:Proton-Translocating ATPases / Q000037:antagonists & inhibitors / Q000378:metabolism
D004272:DNA, Mitochondrial; D004791:Enzyme Inhibitors; D009840:Oligomycins; D000255:Adenosine Triphosphate; D000251:Adenosine Triphosphatases; D006180:Proton-Translocating ATPases