Cloned (Comment) | Organism |
---|---|
mutant genes, poxB3 and posB4, are cloned on plasmid pBR322 | Escherichia coli K-12 |
Protein Variants | Comment | Organism |
---|---|---|
A467T | mutant poxB4 is deficient in lipid activation. Mutation is located in the C-terminal half of the gene. The difference between poxB3 and poxB4 is the binding of Triton detergents | Escherichia coli K-12 |
S536P | mutant poxB3 is deficient in lipid activation but retains full catlytic activity. Mutation is located in the C-terminal half of the gene. The difference between poxB3 and poxB4 is the binding of Triton detergents | Escherichia coli K-12 |
Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|
cell envelope | the pyruvate oxidase system and the electron transport system are associated with the cell envelope-membrane fraction | Escherichia coli | 30313 | - |
Metals/Ions | Comment | Organism | Structure |
---|---|---|---|
alpha-chymotrypsin | 20 micromol/ml, wild-type enzyme and the mutant poxB4 are activated 15- and 70fold, respectively, and the mutant poxB3 is activated 14fold | Escherichia coli K-12 | |
SDS | 20 microM, activates the wild-type and mutant enzymes, poxB3 and poxB4, 15-, 20-, and 70fold, respectively | Escherichia coli K-12 | |
Triton X-100 | 2.2 mM, activates the wild-type and mutant enzymes, poxB3 and poxB4, 32-, 4-, and 6fold, respectively. With the addition of alpha-chymotrypsin the activation of the mutant enzymes poxB3 and poxB4 is increased 14- and 39fold, respectively | Escherichia coli K-12 |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Escherichia coli | - |
- |
- |
Escherichia coli K-12 | - |
- |
- |
Purification (Comment) | Organism |
---|---|
the poxB4 mutant is purified from the strain CG3, carrying plasmid pYYC16, which overproduces the enzyme about 20fold. Purified on DEAE-cellulose, >90% pure | Escherichia coli K-12 |
Renatured (Comment) | Organism |
---|---|
removal of the lipids from the membrane particles by extraction with aqueous acetone or hydrolysis of the phospholipids by treatment with Bacillus cereus phospholipase C results in a complete loss of electron transport activity. Practically all the neutral lipids and 65% of the phospholipids are removed by this treatment. Phospholipase treatment results in a loss of 75% of the membrane phospholipid phosphorus. The diglycerides and the neutral lipids produced by phospholipase hydrolysis remain associated with the particles. Addition of neutral lipid and detergent hepta-D,L-alanyl-dodecylamide to the acetone-extracted material results in a restoration of 37% of the original particle activity. Addition of neutral lipid and hepta-DL-alanyl dodecylamide to phospholipase-treated particles completely restores the original electron transport activity. Addition of ubiquinone from either yeast or Escherichia coli will restore pyruvate oxidase activity when the quinones are supplemented with photoinactivated neutral lipid. No restoration of activity to phospholipase-treated particles is noted upon the addition of either menaquinone 6 or menaquinone 8 to the reconstitution system | Escherichia coli |
Specific Activity Minimum [µmol/min/mg] | Specific Activity Maximum [µmol/min/mg] | Comment | Organism |
---|---|---|---|
60 | - |
mutant poxB4 in presence of 20 microM SDS, pH and temperature not specified in the publication | Escherichia coli K-12 |
90 | - |
wild-type enzyme, pH and temperature not specified in the publication | Escherichia coli K-12 |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
pyruvate + ferricyanide + H2O | - |
Escherichia coli K-12 | acetate + CO2 + ferrocyanide | - |
? |
Synonyms | Comment | Organism |
---|---|---|
pyruvate oxidase | - |
Escherichia coli |
pyruvate oxidase | - |
Escherichia coli K-12 |