Genetics of the Adenosine Triphosphatase Complex of Escherichia coli

A new mutant strain of Escherichia coli in which phosphorylation is uncoupled from electron transport was isolated. The new mutant strain has a similar phenotype to the uncB mutant described previously; results from reconstitution experiments in vitro indicate that the new mutation also affects a component of the F0 portion of the Mg2+-stimulated adenosine triphosphatase. A method was developed to incorporate mutant unc alleles into plasmids. Partial diploid strains were prepared in which the uncB402 allele was incorporated into the plasmid and the new unc mutation into the chromosome, or vice versa. Complementation between the mutant unc alleles was indicated by growth on succinate, growth yields on glucose, ATP-dependent transhydrogenase activities, ATP-induced atebrin-fluorescence quenching and oxidative-phosphorylation measurements. The gene in which the new mutation occurs is therefore distinct from the uncB gene, and the mutant allele was designated uncC424.

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Partial diploids of Escherichia coli carrying normal and mutant alleles affecting oxidative phosphorylation

Biochemical Journal ◽

10.1042/bj1620665 ◽

1977 ◽

Vol 162 (3) ◽

pp. 665-670 ◽

Cited By ~ 46

Author(s):

F Gibson ◽

G B Cox ◽

J A Downie ◽

J Radik

Keyword(s):

Escherichia Coli ◽

Fluorescence Quenching ◽

Oxidative Phosphorylation ◽

Atpase Activity ◽

Adenosine Triphosphatase ◽

Growth Yields ◽

Normal Allele ◽

Adenosine Triphosphatase Activity

A plasmid was isolated which included the region of the Escherichia coli chromosome carrying the known genes concerned with oxidative phosphorylation (unc genes). This plasmid was used to prepare partial diploids carrying normal unc alleles on the episome and one of the three mutant alleles (unc A401, uncB402 or unc-405) on the chromosome. These strains were compared with segregants from which the plasmid had been lost. Dominance of either normal ormutant unc alleles was determined by growth on succinate, growth yields on glucose, Mg-ATPase (Mg2+-stimulated adenosine triphosphatase) activity, atebrin-fluorescence quenching, ATP-dependent transhydrogenase activity and oxidative phosphorylation. In all the above tests, dominance of the normal allele was observed. However, in membranes from the diploid strains which carried a normal allele and either of the mutant alleles affecting Mg-ATPase activity (uncA401 or unc-405), the energy-linked functions were only partially restored.

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Specificity of the proton adenosine triphosphatase of Escherichia coli for adenine, guanine, and inosine nucleotides in catalysts and binding

Biochemistry ◽

10.1021/bi00316a026 ◽

1984 ◽

Vol 23 (21) ◽

pp. 4998-5003 ◽

Cited By ~ 80

Author(s):

David S. Perlin ◽

Lisa R. Latchney ◽

John G. Wise ◽

Alan E. Senior

Keyword(s):

Escherichia Coli ◽

Adenosine Triphosphatase

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Mutations in the uncE gene affecting assembly of the c-subunit of the adenosine triphosphatase of Escherichia coli

Biochemical Journal ◽

10.1042/bj2110717 ◽

1983 ◽

Vol 211 (3) ◽

pp. 717-726 ◽

Cited By ~ 37

Author(s):

D A Jans ◽

A L Fimmel ◽

L Langman ◽

L B James ◽

J A Downie ◽

...

Keyword(s):

Escherichia Coli ◽

Amino Acid ◽

Cell Membrane ◽

Dna Sequences ◽

Adenosine Triphosphatase ◽

Gene Dosage ◽

Base Change ◽

Amino Acid Substitutions ◽

Helical Hairpin ◽

C Subunit

The amino acid substitutions in the mutant c-subunits of Escherichia coli F1F0-ATPase coded for by the uncE429, uncE408 and uncE463 alleles affect the incorporation of these proteins into the cell membrane. The DNA sequence of the uncE429 allele differed from normal in that a G leads to A base change occurred at nucleotide 68 of the uncE gene, resulting in glycine being replaced by aspartic acid at position 23 in the c-subunit. The uncE408 and uncE463 mutant DNA sequences were identical and differed from normal in that a C leads to T base change occurred at nucleotide 91 of the uncE gene, resulting in leucine being replaced by phenylalanine at position 31 in the c-subunit. An increased gene dosage of the uncE408 or uncE463 alleles resulted in the incorporation into the membranes of the mutant c-subunits. The results are discussed in terms of the ‘Helical Hairpin Hypothesis’ of Engelman & Steitz [(1981) Cell 23,411-422].

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