A NOVEL POINT MUTATION IN rpsL GENE OF STREPTOMYCES COELICOLOR WITH ENHANCED BLUE PIGMENT PRODUCTION

Abstract

Three strains showing enhanced blue pigment production were screened among
thirty streptomycin resistant mutants of Streptomyces coelicolor 100. Their yields of blue
pigment were all improved, especially for mutant S-3. Analysis of the mutants revealed
that a point mutation occurred in mutant S-3. In rpsL gene, A to G transition at the
position 128 resulted in Lys-43 to Arg substitution in the ribosomal protein S12 encoded
by rpsL gene. There was no mutation in rpsL gene of other two streptomycin resistant
mutants. Compared with the wild type strain, the mutant S-3 showed increased blue
pigment yield and slightly decreased growth rate. This strategy of streptomycin resistance
induction could be especially effective for improving the blue pigment production from
the wild type strain of Streptomyces coelicolor.