D-(+)-lactate dehydrogenase from Lactobacillus murinus.

A M Strasser de Saad; A A Pesce de Ruiz Holgado; G Oliver

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PubMed · 3768146

D-(+)-lactate dehydrogenase from Lactobacillus murinus.

A M Strasser de Saad·A A Pesce de Ruiz Holgado·G Oliver

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Abstract

D-(+)-Lactate dehydrogenase from Lactobacillus murinus was purified 670-fold. The Mr was 140,000 as determined by gel filtration. Maximum enzymatic activity was observed at 25 degrees C and pH 6.0 in 200 mM Na2KPO4 buffer. When the temperature was increased from 60 to 65 degrees C, the enzyme was completely inactive in 5 min. The apparent Km for pyruvate and NADH were 4.7 x 10(-4) and 1 x 10(-5) M, respectively. Pyruvate analogs such as oxalate, oxamate, 2-oxobutyrate, and malonate acted as a competitive inhibitors. L-Lactate and L-malate were noncompetitive inhibitors.

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Bacterial Proteins Hot Temperature Hydrogen-Ion Concentration L-Lactate Dehydrogenase Lactobacillus Substrate Specificity Journal Article

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A M Strasser de Saad, A A Pesce de Ruiz Holgado, G Oliver. 1986. D-(+)-lactate dehydrogenase from Lactobacillus murinus.. https://pubmed.ncbi.nlm.nih.gov/3768146/

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