title: Production of L-asparaginase by Streptomyces karnatakensis and Streptomyces venezuelae.
abstract: Production of L-asparaginase by two soil isolates, identified as S. karnatakensis and S. venezuelae, was investigated under different environmental and nutritional conditions. The presence of carbon sources, other than starch, in the growth medium or amino acids, other than L-asparagine-inhibited the enzyme biosynthesis. L-aspartic inhibited growth and enzyme production, due to a feedback mechanism, and/or lowering the pH value. Both organisms were stimulated to produce more enzyme with increasing concentrations of starch and L-asparagine, however, the optimum starch and L-asparagine concentration depended on the tolerance of the organism to low and high pH, respectively. Aeration stimulated growth, but not enzyme production, and both organisms produced more enzyme in static cultures than in shaken cultures.
mesh_terms: D000596:Amino Acids / Q000378:metabolism; D001215:Asparaginase / Q000096:biosynthesis*; D001216:Asparagine / Q000378:metabolism; D003470:Culture Media; D006863:Hydrogen-Ion Concentration; D012988:Soil Microbiology; D013045:Species Specificity; D013213:Starch / Q000378:metabolism; D013237:Stereoisomerism; D013302:Streptomyces / Q000201:enzymology* / Q000254:growth & development / Q000378:metabolism
chemical_list: D000596:Amino Acids; D003470:Culture Media; D001216:Asparagine; D013213:Starch; D001215:Asparaginase