Construction of the expression vector based on the growth phase-and growth rate-dependent rmf promoter:use of cell growth rate to control the expression of cloned genes in Escherichia coli

摘要

A novel expression vector base don the rmf promoter(Wada et al.Proc,Natl.Acad.Sci.USA(1995) 87:2657-2661) was developed.Using lacZ gene as a model,protein production depending on cell growth pahse and growth rate was found.In addition,by subjecting therecombinant cells to temperature downshift and substrate famine,the strain was capable of producing 35000-40000 units of #beta#-galactosidase.These characteristics indicate the potential application of this expression vector to bioprocessing such as protein production in continuous or batch fermentation,biotransformation using entrapped cells,and in situ bioremediation.