|
KMID : 0545120150250111819
|
|
Journal of Microbiology and Biotechnology
2015 Volume.25 No. 11 p.1819 ~ p.1826
|
|
|
Construction of a Genetic System for Streptomyces albulus PD-1 and Improving Poly(ε-L-lysine) Production Through Expression of Vitreoscilla Hemoglobin
|
|
Xu Zhao Xian
Cao Chang Hong
Sun Zhu Zhen
Li Sha
Xu Zheng
Feng Xiao Hai
Xu Hong
|
|
|
Abstract
|
|
|
|
Poly(ε-L-lysine) (ε-PL) is a novel bioactive polymer secreted by filamentous bacteria. Owing to lack of a genetic system for most ε-PL-producing strains, very little research on enhancing ε-PL biosynthesis by genetic manipulation has been reported. In this study, an effective genetic system was established via intergeneric conjugal transfer for Streptomyces albulus PD-1, a famous ε-PL-producing strain. Using the established genetic system, the Vitreoscilla hemoglobin (VHb) gene was integrated into the chromosome of S. albulus PD-1 to alleviate oxygen limitation and to enhance the biosynthesis of ε-PL in submerged fermentation. Ultimately, the production of ε-PL increased from 22.7 g/l to 34.2 g/l after fed-batch culture in a 5 L bioreactor. Determination of the oxygen uptake rate, transcriptional level of ε-PL synthetase gene, and ATP level unveiled that the expression of VHb in S. albulus PD-1 enhanced ε-PL biosynthesis by improving respiration and ATP supply. To the best of our knowledge, this is the first report on enhancing ε-PL production by chromosomal integration of the VHb gene in an ε-PL-producing strain, and it will open a new avenue for ε-PL production.
|
|
|
KEYWORD
|
|
|
Poly(ε-L-lysine), Submerged fermentation, Vitreoscilla hemoglobin, Dissolved oxygen, Streptomyces albulus, Genetic system
|
|
|
FullTexts / Linksout information
|
|
|
|
|
|
Listed journal information
|
|
  
|