Isolation of Methionine - Producing Streptomyces Species from South Indian soil

Abstract

Actinomycetes isolated from soil were investigated for methionine production, and an isolate, designated SP-05, was recovered. Taxonomic studies showed that the strain has good growth, sporulation and black pigment production on most media, utilized various sugars, reduced nitrates and degraded tyrosine. The aerial mycelia have spore chains with open loops, and therefore belong to retinaculum apertum group. Presence of LL diaminopimelic acid on the cell wall of isolate SP-05 also suggested that the strain belongs to the genus Streptomyces. The organism was found to produce 3.72 mg/ml methionine in culture broth. Sucrose and ammonium chloride at concentrations of 8.0 and 6.0% (w/v) respectively, in the culture medium, enhanced methionine production.