Isolation and Identification of Ophiocordyceps sinensis and the Diversity of Its' PKS and NRPS Functional Genes

To explore the inheritance of Ophiocordyceps sinensis and the diversity of the polyketide synthase (PKS) and non-ribosomal peptide synthase (NRPS) genes and to lay the foundation of looking for the potential strains of the synthesis of bioactive substances. A strain of fungi ZG4-23 with strong antibacterial activity was isolated from O. sinensis by tissue isolation method. The multilocus phylogenetic analysis was used for identification of the fungi. PKS and NRPS genes fragments were PCR amplified from genomic DNA with degenerate primers. The biosynthetic potential of strain ZG4-23 was accessed by bioinformatic and phylogenetic analyses of PKS and NRPS genes sequences. The polygenes sequence analysis showed that, the sequence homology was 99% between the strain ZG4-23 and the multiple strains of O. sinensis.The strain contained PKS I gene and NRPS gene. The PKS I sequence had 99% homology compared with O. sinensis PKS gene. The NRPS gene sequence had 76% homology with Trichophyton rubrum NRPS gene. This study demonstrated that O. sinensis had potential capacity to synthesize bioactive secondary metabolite, which was worth of further research and development.