Induction condition of secondary metabolites production in soil actinomycetes, rhodococcus jostii RHA1

Abstract

Rhodococcus jostii RHA1 is a potent polychlorinated biphenyl-degrading soil actinomycete that catabolizes a wide range of compounds and represents a genus of considerable chemical and industrial interest. Genome of RHA1 contains nonribosomal peptide synthase (NRPS) genes, and polyketide synthase (PKS) genes, providing evidence that RHA1 harbor an extensive secondary metabolism as same as other actinomycetes. To elucidate R. jostii RHA1 may produce any kinds of secondary metabolites, induction condition of these secondary metabolite production genes were investigated. Type I, type III, PKS-NRPS hybrid located on chromosome, and NRPSs located on plasmid were typically induced on solid medium with specific nutrient or environment condition. On the other hands, type II PKSs located on chromosome were mainly induced on liquid medium with specific condition. These results indicated that secondary metabolites induced on specific condition on solid or liquid medium by RHA1 might play a key role of surviving under severe environmental condition.