Analysis of actinomycetes isolated from Grand Shangri-La soil

Abstract:

[Objective] To obtain new pharmaceuticals and enzymes with high activity, we studied the composition as well as antimicrobial and enzyme activities of actinomycetes in Grand Shangri-La. [Methods] Using 4 media, we isolated mesophilic and psychrophilic actinomycetes from 220 soil samples collected from areas with different altitudes in Grand Shangri-La. Twenty-five representative isolates were phylogenetically analyzed based on their 16S rRNA gene sequences. Antimicrobial activities against four bacteria and seven fungi were tested using agar well diffusion method. Genes encoding typeⅠandⅡ polyketide synthases (PKSⅠ, PKSⅡ), nonribosomal peptide synthase (NRPS) and polyene cytochrome P450 hydroxylase (CYP) were screened by PCR. Furthermore, several enzyme activities of psychrophilic actinomycetes were examined. [Results] The 25 representative strains belonged to 6 suborders, 12 families and 15 genera of the order Actinomycetals. For NRPS and CYP genes screening, positive strains were 14 and 11, respectively. Among the 111 actinomycetes isolated under low-temperature conditions, 88% were psychrotroph strains, 12% were psychrophilic actinomycetes, and most of them utilized gelatin, cellulose and chitin. [Conclusion] Actinomycetes diversity isrich in Grand Shangri-la, and has the potential for conservation and utilization of actinomycetes resources.