title: [Isolation and characterization of a new epsilon-poly-L-lysine-producing strain TUST-2].
abstract: OBJECTIVE
  Epsilon-Poly-L-Lysine (epsilon-PL) is a natural amino acid homopolymer. The study aimed at isolating new epsilon-PL-producing strains.
  
  
  METHODS
  epsilon-PL-producing strains were screened from the soil by using a new isolation approach which had three steps, (1) enrichment culturing epsilon-PL toleranting strains; (2) screening by improved Nishikawa's method; (3) selection of strains with higher epsilon-PL tolerant ability.
  
  
  RESULTS
  A new epsilon-PL-producing strain TUST-2 was isolated from the soil collected from Hainan province, China. Chemotaxonomic and morphological characteristics of the isolate were typical of strain of the genus Streptomyces. The strain TUST-2 was found to belong to Streptomyces diastatochromogenes by comparative 16S rRNA gene sequence analysis. The purified fermentation product of the strain TUST-2 was confirmed as epsilon-PL by characteristic analysis, hydrolysate analysis, infrared spectrum, 1H NMR Spectrum, 13C NMR Spectrum, and MALDI-TOF-MS.
  
  
  CONCLUSIONS
  On the basis of 16S rRNA gene sequence analysis and its morphological and physiological characteristics, epsilon-PL-producing strain TUST-2 is a new isolate of Streptomyces diastatochromogenes, named as Streptomyces diastatochromogenes TUST-2.
authors.affiliation: School of Biotechnology, Tianjin University of Science & Technology, Key Laboratory of Industrial Microbiology of Ministry of Education, Tianjin 300457, China. jiashiru@tust.edu.cn
authors.forename: Shiru
authors.initials: S
authors.lastname: Jia
authors.forename: Chunying
authors.initials: C
authors.lastname: Xu
authors.forename: Zhilei
authors.initials: Z
authors.lastname: Tan
authors.forename: Weifeng
authors.initials: W
authors.lastname: Cao
authors.forename: Hongyu
authors.initials: H
authors.lastname: Ou
authors.forename: Xinyi
authors.initials: X
authors.lastname: He
authors.forename: Zixin
authors.initials: Z
authors.lastname: Deng
mesh_terms: D002681:China; D008969:Molecular Sequence Data; D010802:Phylogeny; D011107:Polylysine / Q000378:metabolism*; D012988:Soil Microbiology; D013302:Streptomyces / Q000145:classification / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism*
chemical_list: D011107:Polylysine