Preparation of a low-cost minimal medium for engineered Escherichia coli with high yield of human-like collagen II.

: In order to reduce the production cost of human-like collagen (HLC), a minimal medium was introduced. On the base of Design of experiments (DOE), especially Plackett-Burman design and central composite design, a modified minimal medium that could give a high yield of HLC was developed. The optimum minimal medium for engineered E. coli BL21 ΔptsG contained 6.11g/L of glucose, 5.82g/L of (NH(4))(2)SO(4), 1.80´10(-4)g/L of thiamine and 3.00´10(-2)L of trace element solution, the other ingredients were same to that in M9 medium. And the HLC production of ptsG mutant reached to 0.26g/L in this optimized minimal medium, which approached to 0.27g/L produced by the strain without deleting ptsG gene in an optimized complex medium.