Authors: Jinsong Feng Jing Jiang Yan Liu Wei Li Ramila Azat Xiaodong Zheng WenWen Zhou
Publish Date: 2016/08/11
Volume: 43, Issue: 10, Pages: 1365-1372
Abstract
Validamycin A ValA synthesized by Streptomyces hygroscopicus 5008 is widely used as a highefficient antibiotic to protect plants from sheath blight disease A novel fermentation strategy was introduced to stimulate ValA production by adding oxygen carriers About 58 increase in ValA production was achieved using liquid paraffin Further biomass carbon source metabolic genes and metabolic enzymes were studied It was also found that the supplementation of liquid paraffin increased the medium dissolved oxygen and intracellular oxidative stress level The expression of the global regulators afsR and soxR sensitive to ROS ugp catalyzing synthesis of ValA precursor and ValA structural genes was enhanced The change of the activities of glucose6phosphate dehydrogenase and glyceraldehyde 3phosphate dehydrogenase was observed which reflected the redirection of carbon metabolic flux Based on these results liquid paraffin addition as an oxygen carrier could be a useful technique in industrial production of ValA and our study revealed a redoxbased secondary metabolic regulation in S hygroscopicus 5008 which provided a new insight into the regulation of the biosynthesis of secondary metabolitesThe authors acknowledge the financial support from Zhejiang Provincial Natural Science Foundation of China LY12B06006 National Natural Science Foundation of China 20906060 Public Project of Zhejiang Province 2016C32007 and Key Project for National Key Research and Development Plan 2016YFD0401201
Keywords: