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Activity of L-asparaginase in cells of Streptomyces karnatakensis.

S A Mostafa
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Abstract

Eight isolates capable of producing varying quantities of L-asparaginase and all identified as members of the genus Streptomyces were isolated from the soil and a suitable technique for the assay of intracellular L-asparaginase in actinomycetes was developed. The most potent L-asparaginase producer was identified as a strain of Streptomyces karnatakensis. Static cultures of S. karnatakensis showed maximum enzyme activity with almost maximum growth while shaken cultures exhibited their activity after 48 hours of growth. This phenomenon is discussed in terms of possible feedback mechanism and/or the biosynthesis of certain pigments. L-asparaginase of S. karnatakensis proved to be mostly intracellular and the presence of L-asparagine in the culture medium though, stimulating yet not essential for the enyzme biosynthesis. Cells grown on L-asparagine showed amidase activity with other amides but at a reduced rate.

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AmidohydrolasesAsparaginaseCulture MediaEgyptHydrogen-Ion ConcentrationSoil MicrobiologySpecies SpecificityStreptomycesTemperatureJournal Article

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BibTeXRIS

S A Mostafa. 1979. Activity of L-asparaginase in cells of Streptomyces karnatakensis.. https://doi.org/10.1016/s0323-6056(79)80007-5

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Amidohydrolases↗
PubMed1979

Isozyme studies on the association of the herpes simplex virus type 1 thymidine kinase gene with human chromosomes in somatic cell hybrids.

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