EFFECT OF EXOGENEOUS METHYL OLEATE ON THE TIME-COURSE OF SOME PARAMETERS OF STREPTOMYCES-HYGROSCOPICUS NRRL B-1865 CULTURE

Addition of methyl oleate to a Streptomyces hygroscopicus NRRL B-1865 culture modified the metabolic properties of this strain. This additio n decreased the pH of the medium, increased the valine uptake of the c ells and reduced their consumption of glucose until the beginning of a ntibiotic biosynthesis, which was delayed. At the same time, an increa se in growth (x 1.8) and a marked improvement in antibiotic production (x 20) could be observed. The use of labelled methyl oleate showed th at methyl oleate was not a precursor of antibiotics produced by S. hyg roscopicus NRRL B-1865. It is suggested that methyl oleate addition ma y cause some alteration in membrane permeability, inducing an increase in H+ extrusion and stimulating the accumulation of branched amino ac ids, known to be direct precursors of polyether antibiotics.