title: Mutants of Escherichia coli K12 unable to grow on non-fermentable carbon substrates.
abstract: Among a number of mutants unable to utilize non-fermentable carbon substrates, scoring for membrane ATPase and for ATP-driven transhydrogenase activity permitted to distinguish two phenotypes: (A) mutants lacking ATPase and ATP-driven transhydrogenase; (B) one mutant with an ATPase which behaved according to several criteria as released into solution instead of being membrane bound, a.o it exhibited no ATP-driven transhydrogenase activity. All A and B mutants exhibited a common nutritional pattern. The ATPase-deficient group, when scored for ATPase-binding sites on its membrane particles revealed three different subgroups: (1) mutants having free ATPase-binding sites, (2) mutants with ATPase-binding sites made available by the procedure which releases ATPase from wild-type membrane, and (3) mutants with no detectable ATPase-binding sites. Membranes of the mutant B with unbound ATPase also exhibited a deficiency in ATPase-binding sites, but its soluble ATPase was also found unable to bind to ATPase-binding sites of wild type membranes. The double alteration, namely abnormal or inactive ATPase and absence of ATPase-binding sites on the membrane is compatible with a single mutational defect.
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D000255:Adenosine Triphosphate / Q000494:pharmacology; D001386:Azides / Q000494:pharmacology; D002462:Cell Membrane / Q000187:drug effects / Q000201:enzymology; D002874:Chromosome Mapping; D004926:Escherichia coli / Q000187:drug effects / Q000201:enzymology*; D007700:Kinetics; D009154:Mutation; D009247:NADH, NADPH Oxidoreductases / Q000378:metabolism; D010101:Oxygen Consumption; D010641:Phenotype
chemical_list: D001386:Azides; D000255:Adenosine Triphosphate; D009247:NADH, NADPH Oxidoreductases; D000251:Adenosine Triphosphatases