Isolation of a specific lipoamide dehydrogenase for a branched-chain keto acid dehydrogenase from Pseudomonas putida.

摘要: We purified lipoamide dehydrogenase from cells of Pseudomonas putida PpG2 grown on glucose (LPD-glu) and valine (LPD-val), which contained branched-chain keto acid dehydrogenase. LPD-glu had a molecular weight 56,000 as determined by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, LPD-val 49,000. The pH optimum for reduced nicotinamide adenine dinucleotide oxidation was 7.4, compared with 6.5 LPD-val. When oxidized included in the assay mixture, optima were 7.1 5.7, respectively. There also difference between two enzymes reduction, but Michaelis constants maximum velocities similar. A preparation dehydrogenase, deficient stimulated 10-fold not LPD-glu, suggested that P. has specific requirement In contrast, partially 2-ketoglutarate LPD-val, indicating this complex LPD-glu. Images