title: Optimization of culture on the overproduction of TRAIL in high-cell-density culture by recombinant Escherichia coli.
abstract: Different nutrient-feeding cultures were carried out in producing recombinant protein of truncated tumor necrosis factor related apoptosis-inducing ligand (TRAIL) (114-281 amino acids of TRAIL) in Escherichia coli strain C600/pBV-TRAIL. The effects of preinduction specific growth rate, postinduction carbon source (glucose and glycerol), and feeding strategies were investigated. The higher preinduction specific growth rate (mu = 0.22 h(-1)) contributed to the increase in the TRAIL production, at which TRAIL was accumulated in bacterial cells as 7.2% of total cellular protein, corresponding to 1.99 g l(-1) in contrast with 5.1% (1.29 g l(-1)) at preinduction specific growth rate (mu = 0.1 h(-1)) during high-cell-density culture. Glycerol was superior to glucose as the postinduction carbon source for TRAIL production. Under similar culture conditions, the final concentration of TRAIL was produced 1.59-fold more when glycerol was used as postinduction carbon source than when glucose was used. At the same time, the results showed that it is efficient to adopt the pH-stat feeding strategy at postinduction for the overproduction of TRAIL. The TRAIL production was increased up to 4.51 g l(-1), approximately 16.1% of total cellular protein. The mechanisms behind the preinduction specific growth rate effect on the expression level may be ascribed to the leakage secretion of acetate.
authors.affiliation: State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, People's Republic of China.
authors.forename: Qingping
authors.initials: Q
authors.lastname: Luo
authors.forename: Ya-Ling
authors.initials: YL
authors.lastname: Shen
authors.forename: Dong-Zhi
authors.initials: DZ
authors.lastname: Wei
authors.forename: Wei
authors.initials: W
authors.lastname: Cao
mesh_terms: D000085:Acetates / Q000378:metabolism; D051017:Apoptosis Regulatory Proteins / Q000096:biosynthesis*; D019149:Bioreactors / Q000382:microbiology; D001709:Biotechnology / Q000379:methods*; D018929:Cell Culture Techniques / Q000379:methods*; D004591:Electrophoresis, Polyacrylamide Gel; D004926:Escherichia coli / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism; D005990:Glycerol / Q000378:metabolism; D008562:Membrane Glycoproteins / Q000096:biosynthesis*; D011994:Recombinant Proteins / Q000032:analysis / Q000096:biosynthesis*; D053221:TNF-Related Apoptosis-Inducing Ligand; D014409:Tumor Necrosis Factor-alpha / Q000096:biosynthesis*
chemical_list: D000085:Acetates; D051017:Apoptosis Regulatory Proteins; D008562:Membrane Glycoproteins; D011994:Recombinant Proteins; D053221:TNF-Related Apoptosis-Inducing Ligand; D014409:Tumor Necrosis Factor-alpha; D005947:Glucose; D005990:Glycerol