title: Oxidative phosphorylation in Escherichia coli K12. An uncoupled mutant with altered membrane structure.
abstract: 1. A new mutant strain (AN228) of Escherichia coli K12, unable to couple phosphorylation to electron transport, has been isolated. The mutant allele (unc-405), in strain AN228, was found to map near the uncA and uncB genes at about minute 74 on the E. coli genome. 2. A transductant strain (AN285) carrying the unc-405 allele is similar to the uncA and uncB mutants described previously in that it is unable to grow on succinate, gives a low aerobic yield on limiting concentrations of glucose, has a normal rate of electron transport, is unable to couple phosphorylation to electron transport, and lacks ATP-dependent transhydrogenase activity. 3. Strain AN285 (unc-405) is similar to an uncA mutant, but different from an uncB mutant, in that it is unable to grow anaerobically in a glucose-mineral-salts medium, and membrane preparations do not have Mg(2+)-stimulated adenosine triphosphatase activity. 4. Strain AN285 (unc-405) does not form an aggregate analogous to the membrane-bound Mg(2+)-stimulated adenosine triphosphatase aggregate found in normal cells. In this respect it differs from strain AN249 (uncA(-)), which forms an inactive membrane-bound Mg(2+)-stimulated adenosine triphosphatase aggregate.
mesh_terms: D000251:Adenosine Triphosphatases / Q000378:metabolism; D000332:Aerobiosis; D000483:Alleles; D000693:Anaerobiosis; D002462:Cell Membrane / Q000201:enzymology / Q000378:metabolism; D002850:Chromatography, Gel; D002874:Chromosome Mapping; D004579:Electron Transport; D004926:Escherichia coli / Q000166:cytology / Q000201:enzymology / Q000378:metabolism*; D005796:Genes; D005838:Genotype; D008274:Magnesium; D009154:Mutation; D009247:NADH, NADPH Oxidoreductases / Q000378:metabolism; D009994:Osmolar Concentration; D010085:Oxidative Phosphorylation; D013056:Spectrophotometry, Ultraviolet; D014161:Transduction, Genetic; D014462:Ultrafiltration
chemical_list: D009247:NADH, NADPH Oxidoreductases; D000251:Adenosine Triphosphatases; D008274:Magnesium