[Diversity of Actinomycetes in Wuling Mountain].
OBJECTIVE
To isolate new actinomycetes for discovering compounds of pharmaceutical importance.


METHODS
We collected 280 soil samples from virgin forest in Wuling Mountain. In total 1134 actinomycetes were isolated by culture-dependent method. Of them 30 strains were selected and then characterized by phylogenetic analysis based on sequences of 16S rRNA gene. Antimicrobial activities were determined by agar well diffusion method, and genes of type I and II polyketide synthases (PKS I, PKS II), nonribosomal peptide synthase (NRPS) and polyene cytochrome P450 hydroxylase (CYP) were screened by PCR.


RESULTS
Thirty strains belonged to 8 families, 13 genera: Streptomyces (>70%), Micromonospora, Dactylosporangium, Catellatospora, Sphaerisporangium, Streptosporangium, Actinomadura, Nonomuraea, Nocardia, Rhodococcus, Arthrobacter, Microbacterium, and Pseudonocardia. There are 5 novel species candidates. Thirty strains showed different antimicrobial activities against one to three bacteria and pathogenic fungi.


CONCLUSIONS
Abundant diversity of actinomycetes existed in the virgin forest of Wuling Mountain which has many new taxa, and Streptomyces is the predominant population. The strains showed high antimicrobial activities and can be further researched for exploiting new compounds of pharmaceutical.
Yunnan Institute of Microbiology and Laboratory for Conservation and Utilization of Bio-resources, Yunnan University, Kunming 650091, China. yanrucao3@yahoo.com.cn
Yanru
Y
Cao
Yi
Y
Jiang
Yiguang
Y
Chen
Shunkun
S
Tang
Sheng
S
Qin
Guozhen
G
Zhao
Lihua
L
Xu
D039903:Actinobacteria / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification / Q000502:physiology; D044822:Biodiversity; D002681:China; D005798:Genes, Bacterial / Q000235:genetics; D010802:Phylogeny; D012336:RNA, Ribosomal, 16S / Q000032:analysis / Q000235:genetics
D012336:RNA, Ribosomal, 16S