title: Comparison of glucose and glycerol as carbon sources for ε-poly-L-lysine production by Streptomyces sp. M-Z18.
abstract: Glucose is widely used in the production of ε-poly-L-lysine (ε-PL); however, glycerol is an emerging carbon source for ε-PL production in recent years. Glycerol is superior to glucose for ε-PL production according to batch and fed-batch fermentations by Streptomyces sp. M-Z18 in this study. To elaborate this difference, physiological metabolism of Streptomyces sp. M-Z18 on glycerol has compared with glucose during batch fermentation. The activities of key enzymes showed that aspartate kinase (ASPK) and ε-PL synthetase (Pls) in glycerol medium was higher than those in glucose, and especially the activity of Pls could enhance by 2.3- and 3.6-fold at 24 and 36 h, respectively. Moreover, metabolism flux analysis demonstrated that a 25 % higher fluxes derived from glycerol are directed into ε-PL synthesis than glucose. As a result, the mechanism of glycerol better than glucose is determined: the activities of ASPK and Pls in glycerol higher than those in glucose, and result in carbon fluxes directed into ε-PL synthesis increased. This study offers a reference to substitute glycerol for conventional glucose as carbon source for ε-PL production.
authors.affiliation: The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, 1800 Lihu Road, Wuxi 214122, Jiangsu Province, China.
authors.forename: Xu-Sheng
authors.initials: XS
authors.lastname: Chen
authors.forename: Zhong-Gui
authors.initials: ZG
authors.lastname: Mao
mesh_terms: D001222:Aspartate Kinase / Q000378:metabolism*; D019149:Bioreactors; D002244:Carbon / Q000378:metabolism; D003470:Culture Media; D005285:Fermentation; D005947:Glucose / Q000378:metabolism*; D005990:Glycerol / Q000378:metabolism*; D007527:Isoenzymes / Q000378:metabolism; D010453:Peptide Synthases / Q000378:metabolism*; D011107:Polylysine / Q000096:biosynthesis*; D013302:Streptomyces / Q000378:metabolism*
chemical_list: D003470:Culture Media; D007527:Isoenzymes; D011107:Polylysine; D002244:Carbon; D001222:Aspartate Kinase; D010453:Peptide Synthases; C533948:epsilon-poly-L-lysine synthethase, Streptomyces albulus; D005947:Glucose; D005990:Glycerol