title: Membrane-bound lactate dehydrogenases and mandelate dehydrogenases of Acinetobacter calcoaceticus. Location and regulation of expression.
abstract: Acinetobacter calcoaceticus possesses an L(+)-lactate dehydrogenase and a D(-)-lactate dehydrogenase. Results of experiments in which enzyme activities were measured after growth of bacteria in different media indicated that the two enzymes were co-ordinately induced by either enantiomer of lactate but not by pyruvate, and repressed by succinate or L-glutamate. The two lactate dehydrogenases have very similar properties to L(+)-mandelate dehydrogenase and D(-)-mandelate dehydrogenase. All four enzymes are NAD(P)-independent and were found to be integral components of the cytoplasmic membrane. The enzymes could be solubilized in active form by detergents; Triton X-100 or Lubrol PX were particularly effective D(-)-Lactate dehydrogenase and D(-)-mandelate dehydrogenase could be selectively solubilized by the ionic detergents cholate, deoxycholate and sodium dodecyl sulphate.
mesh_terms: D000150:Acinetobacter / Q000201:enzymology*; D000429:Alcohol Oxidoreductases / Q000378:metabolism*; D002462:Cell Membrane / Q000201:enzymology; D003902:Detergents; D004790:Enzyme Induction; D007527:Isoenzymes / Q000378:metabolism*; D007770:L-Lactate Dehydrogenase / Q000096:biosynthesis / Q000378:metabolism*; D012995:Solubility
chemical_list: D003902:Detergents; D007527:Isoenzymes; D000429:Alcohol Oxidoreductases; D007770:L-Lactate Dehydrogenase; C021538:L-mandelate dehydrogenase