title: The F1F0-ATPase of Escherichia coli. Substitution of proline by leucine at position 64 in the c-subunit causes loss of oxidative phosphorylation.
abstract: The uncE410 allele differs from the normal uncE gene in that C leads to T base changes occur at nucleotides 190 and 191, resulting in proline at position 64 in the c-subunit of the F1F0-ATPase being replaced by leucine. Two partial-revertant strains were isolated in which alanine-20 of the c-subunit was replaced by proline, owing to a G leads to C base change at nucleotide 58. These c-subunits, coded for by the uncE501 and uncE502 alleles, therefore contained two amino acid changes, namely proline-64 leads to leucine, and alanine-20 leads to proline. Membranes prepared from the partial-revertant strains lacked ATP-dependent atebrin-fluorescence-quenching activity but were able to carry out oxidative phosphorylation. The ATPase activity of the F1-ATPase was inhibited when bound to membranes from strains carrying the uncE410, uncE501 and uncE502 alleles. It is concluded that a bend in the helix axis in one of the arms of the c-subunit hairpin structure is required for integration of the c-subunit into a functional F1F0-ATPase.
mesh_terms: D000251:Adenosine Triphosphatases / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D000483:Alleles; D000595:Amino Acid Sequence; D002462:Cell Membrane / Q000201:enzymology; D004926:Escherichia coli / Q000201:enzymology* / Q000235:genetics; D007930:Leucine / Q000378:metabolism; D008956:Models, Chemical; D009876:Operon; D010085:Oxidative Phosphorylation; D011392:Proline / Q000378:metabolism; D006180:Proton-Translocating ATPases
chemical_list: D011392:Proline; D000251:Adenosine Triphosphatases; D006180:Proton-Translocating ATPases; D007930:Leucine