Oxidation of d-Amino Acids by a Particulate Enzyme from Pseudomonas aeruginosa
Oxidation of d-Amino Acids by a Particulate Enzyme from Pseudomonas aeruginosa
复制标题
铜绿假单胞菌颗粒酶氧化 d-氨基酸
DOI:
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发表时间:
1968
影响因子:
3.2
通讯作者:
J. R. Sokatch
中科院分区:
文献类型:
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作者:
V. P. Marshall;J. R. Sokatch
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 × 10-3m 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 α, β, and γ 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.