title: Oxidation of D-amino acids by a particulate enzyme from Pseudomonas aeruginosa.
abstract: A particulate d-amino acid dehydrogenase has been partially purified from cell free extracts of Pseudomonas aeruginosa grown on dl-valine as the source of carbon and energy. A standard assay was developed which utilized 2,6-dichlorophenol-indophenol as the electron acceptor. The pH optimum for enzyme activity ranged from 6.0 to 8.0, depending on the amino acid assayed. The enzyme was most active with monoamino-monocarboxylic amino acids and histidine. The Michaelis constant for d-phenylalanine was found to be 1.3 x 10(-3)m d-phenylalanine. Constants could not be calculated for the other amino acids oxidized because anomalous plots of V as a function of V/S were obtained. Spectra of enzyme preparations reduced with d-valine or sodium hydrosulfite exhibited adsorption bands typical of the alpha, beta, and gamma bands of cytochromes as well as bleaching in the flavin region of the spectrum. When dl-valine was added to a medium with glycerol as the energy source, d-amino acid dehydrogenase was detected after the addition of valine and was produced at a rate directly proportional to the synthesis of total protein. The enzyme was formed when d-valine, l-valine, or dl-alanine was the source of carbon and energy, but not when glucose, glycerol, or succinate was the energy source.
mesh_terms: D000409:Alanine / Q000378:metabolism; D000596:Amino Acids / Q000378:metabolism*; D003605:D-Amino-Acid Oxidase / Q000032:analysis / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism; D005990:Glycerol / Q000378:metabolism; D006639:Histidine / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D010649:Phenylalanine / Q000378:metabolism; D011550:Pseudomonas aeruginosa / Q000201:enzymology*; D013386:Succinates / Q000378:metabolism; D014633:Valine / Q000378:metabolism
chemical_list: D000596:Amino Acids; D013386:Succinates; D010649:Phenylalanine; D006639:Histidine; D003605:D-Amino-Acid Oxidase; D014633:Valine; D005947:Glucose; D000409:Alanine; D005990:Glycerol