caa a22 4500 606212132 CHVBK 20210128101041.0 cr unu---uuuuu 210128e20150601xx s 000 0 eng 10.1007/s10295-015-1611-z doi (NATIONALLICENCE)springer-10.1007/s10295-015-1611-z Comparative metabolic profiling reveals the key role of amino acids metabolism in the rapamycin overproduction by Streptomyces hygroscopicus [Elektronische Daten] [Baohua Wang, Jiao Liu, Huanhuan Liu, Di Huang, Jianping Wen] Rapamycin is an important natural macrolide antibiotic with antifungal, immunosuppressive and anticancer activity produced by Streptomyces hygroscopicus. In this study, a mutant strain obtained by ultraviolet mutagenesis displayed higher rapamycin production capacity compared to the wild-type S. hygroscopicus ATCC 29253. To gain insights into the mechanism of rapamycin overproduction, comparative metabolic profiling between the wild-type and mutant strain was performed. A total of 86 metabolites were identified by gas chromatography-mass spectrometry. Pattern recognition methods, including principal component analysis, partial least squares and partial least squares discriminant analysis, were employed to determine the key biomarkers. The results showed that 22 potential biomarkers were closely associated with the increase of rapamycin production and the tremendous metabolic difference was observed between the two strains. Furthermore, metabolic pathway analysis revealed that amino acids metabolism played an important role in the synthesis of rapamycin, especially lysine, valine, tryptophan, isoleucine, glutamate, arginine and ornithine. The inadequate supply of amino acids, or namely "nitrogen starvation” occurred in the mutant strain. Subsequently, the exogenous addition of amino acids into the fermentation medium of the mutant strain confirmed the above conclusion, and rapamycin production of the mutant strain increased to 426.7mg/L after adding lysine, approximately 5.8-fold of that in the wild-type strain. Finally, the results of real-time PCR and enzyme activity assays demonstrated that dihydrodipicolinate synthase involved with lysine metabolism played vital role in the biosynthesis of rapamycin. These findings will provide a theoretical basis for further improving production of rapamycin. Society for Industrial Microbiology and Biotechnology, 2015 Metabolomics nationallicence Exogenous feeding strategy nationallicence Real-time PCR nationallicence Enzyme activity assays nationallicence Dihydrodipicolinate synthase nationallicence Wang Baohua Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, 300072, Tianjin, People's Republic of China aut Liu Jiao Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, 300072, Tianjin, People's Republic of China aut Liu Huanhuan Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, 300072, Tianjin, People's Republic of China aut Huang Di Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, TEDA, 300457, Tianjin, People's Republic of China aut Wen Jianping Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, 300072, Tianjin, People's Republic of China aut Journal of Industrial Microbiology & Biotechnology Springer Berlin Heidelberg 42/6(2015-06-01), 949-963 1367-5435 42:6<949 2015 42 10295 https://doi.org/10.1007/s10295-015-1611-z text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s10295-015-1611-z text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Wang Baohua Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, 300072, Tianjin, People's Republic of China aut NATIONALLICENCE 700 1- Liu Jiao Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, 300072, Tianjin, People's Republic of China aut NATIONALLICENCE 700 1- Liu Huanhuan Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, 300072, Tianjin, People's Republic of China aut NATIONALLICENCE 700 1- Huang Di Key Laboratory of Molecular Microbiology and Technology, Ministry of Education, TEDA Institute of Biological Sciences and Biotechnology, Nankai University, 23 Hongda Street, TEDA, 300457, Tianjin, People's Republic of China aut NATIONALLICENCE 700 1- Wen Jianping Key Laboratory of Systems Bioengineering (Ministry of Education), Tianjin University, 300072, Tianjin, People's Republic of China aut NATIONALLICENCE 773 0- Journal of Industrial Microbiology & Biotechnology Springer Berlin Heidelberg 42/6(2015-06-01), 949-963 1367-5435 42:6<949 2015 42 10295