title: [Diversity and bioactivity 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 type I and II polyketide synthases (PKS I, PKS II), 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.
  
  
  CONCLUSIONS
  Actinomycetes diversity is rich in Grand Shangri-la, and has the potential for conservation and utilization of actinomycetes resources.
authors.affiliation: Yunnan Institute of Microbiology, National Engineering Center for Research of Microbial Pharmaceuticals, Yunnan University, Kunming 650091, China. yanrucao3@yahoo.com.cn
authors.forename: Yanru
authors.initials: Y
authors.lastname: Cao
authors.forename: Yi
authors.initials: Y
authors.lastname: Jiang
authors.forename: Lihua
authors.initials: L
authors.lastname: Xu
mesh_terms: D039903:Actinobacteria / Q000145:classification / Q000201:enzymology / Q000235:genetics / Q000302:isolation & purification*; D001419:Bacteria / Q000235:genetics / Q000302:isolation & purification*; D044822:Biodiversity; D002681:China; D004275:DNA, Ribosomal / Q000032:analysis / Q000235:genetics; D010453:Peptide Synthases / Q000378:metabolism; D010802:Phylogeny; D048630:Polyketide Synthases / Q000378:metabolism; D012336:RNA, Ribosomal, 16S / Q000032:analysis* / Q000235:genetics; D017422:Sequence Analysis, DNA; D012988:Soil Microbiology
chemical_list: D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S; D048630:Polyketide Synthases; D010453:Peptide Synthases; C104385:non-ribosomal peptide synthase