Stimulation of L-asparate beta-decarboxylase formation by L-glutamate in Pseudomonas dacunhae and Improved production of L-alanine.
The formation of L-asparate beta-decarboxylase by Pseudomonas dacunhae was compared on media containing a variety of organic acids and amino acids as a carbon source. Although the enzyme was formed constitutively when the organism was grown on basal medium or on that containing tricarboxylic acid cycle intermediates, it was induced twofold by L-glutamate and repressed one-tenth by L-serine. L-Glutamine, L-proline, L-leucine, glycine, and L-threonine also showed induction effects lower than that of L-glutamate. L-Glutamate derepressed the serine effect. This glutamate effect was observed effect was observed with other microoganisms, e.g., Achromobacter pestifer and Achromobacter liquidum. Since the intermediates from L-glutamate metabolism had no effect, this induction effect was specific to L-glutamate. The formation of some glutamate-related enzymes was measured and is discussed in relation to the formation of L-asparate beta-decarboxylase. L-Asparate beta-decarboxylase was purified to an electrophoretically homogenous state from L-glutamate-grown cells of P. dacunhae, and some properties were compared with those of the enzyme from fumarate-grown cells. The two enzymes were identical in disc electrophoresis, molecular weight, and some enzymatic properties. The industrial production of L-alanine from L-aspartic acid acid was improved by using the culture broth with highly induced L-asparate beta-decarboxylase (9.4 U/ml of broth).
D000409:Alanine / Q000096:biosynthesis*; D000596:Amino Acids / Q000378:metabolism; D002262:Carboxy-Lyases / Q000096:biosynthesis* / Q000302:isolation & purification; D005285:Fermentation; D005650:Fumarates / Q000378:metabolism; D005971:Glutamates / Q000378:metabolism*; D011549:Pseudomonas / Q000378:metabolism*; D013237:Stereoisomerism
D000596:Amino Acids; D005650:Fumarates; D005971:Glutamates; D002262:Carboxy-Lyases; D000409:Alanine