Weitao Geng and Chao Yang contributed equally to this work.
Cloning of ε-poly-L-lysine (ε-PL) synthetase gene from a newly isolated ε-PL-producing Streptomyces albulus NK660 and its heterologous expression in Streptomyces lividans
Article first published online: 14 JAN 2014
© 2014 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.
This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
Volume 7, Issue 2, pages 155–164, March 2014
How to Cite
Geng, W., Yang, C., Gu, Y., Liu, R., Guo, W., Wang, X., Song, C. and Wang, S. (2014), Cloning of ε-poly-L-lysine (ε-PL) synthetase gene from a newly isolated ε-PL-producing Streptomyces albulus NK660 and its heterologous expression in Streptomyces lividans. Microbial Biotechnology, 7: 155–164. doi: 10.1111/1751-7915.12108
Funding Information The authors gratefully acknowledge the financial support from National Key Basic Research Program of China (‘973’ Program, 2012CB725204), National High Technology Research and Development Program of China (‘863’ Program, 2012AA021505), Natural Science Foundation of China (grant nos. 31070039, 31170030, 51073081 and 31300032), Project of Tianjin, China (grant no. 13JCQNJC09700).
- Issue published online: 14 FEB 2014
- Article first published online: 14 JAN 2014
- Manuscript Accepted: 16 DEC 2013
- Manuscript Revised: 12 DEC 2013
- Manuscript Received: 4 OCT 2013
- National Key Basic Research Program of China. Grant Number: 2012CB725204
- National High Technology Research and Development Program of China. Grant Number: 2012AA021505
- Natural Science Foundation of China. Grant Numbers: 31070039, 31170030, 51073081, 31300032
- Project of Tianjin, China. Grant Number: 13JCQNJC09700
ε-Poly-L-lysine (ε-PL), showing a wide range of antimicrobial activity, is now industrially produced as a food additive by a fermentation process. A new strain capable of producing ε-PL was isolated from a soil sample collected from Gutian, Fujian Province, China. Based on its morphological and biochemical features and phylogenetic similarity with 16S rRNA gene, the strain was identified as Streptomyces albulus and named NK660. The yield of ε-PL in 30 l fed-batch fermentation with pH control was 4.2 g l−1 when using glycerol as the carbon source. The structure of ε-PL was determined by nuclear magnetic resonance (NMR) and matrix-assisted laser desorption/ionization–time of flight mass spectrometry (MALDI-TOF MS). Previous studies have shown that the antimicrobial activity of ε-PL is dependent on its molecular size. In this study, the polymerization degree of the ε-PL produced by strain NK660 ranged from 19 to 33 L-lysine monomers, with the main component consisting of 24–30 L-lysine monomers, which implied that the ε-PL might have higher antimicrobial activity. Furthermore, the ε-PL synthetase gene (pls) was cloned from strain NK660 by genome walking. The pls gene with its native promoter was heterologously expressed in Streptomyces lividans ZX7, and the recombinant strain was capable of synthesizing ε-PL. Here, we demonstrated for the first time heterologous expression of the pls gene in S. lividans. The heterologous expression of pls gene in S. lividans will open new avenues for elucidating the molecular mechanisms of ε-PL synthesis.