CONSTRUCTION OF THE PLASMID pKChiA AND pMchiA CARRYING CHITINASE GENE AND THEIR EXPRESSION IN E.coli / 微生物学通报

ABSTRACT

A 1.8 kb HinfI fragment carrying the chitinase gene(chiA) from Serratia marcescens was isolated from the plasmid pLCHIA and was inserted into the SmaI site downstream of the strong Ptac promoter in the expression vector pKK223-3,yielding the plasmid pKChiA.The 2.1 kb PtacChiA fusion fragment was excised by BamHI from the plasmid pKChiA and was inserted into the single BamHI site present within the plasmid pMC71A,thus generating the plasmid pMChiA.High levels of chitinase were produced by the E.coli strains HB101 and JM105 carrying the plasmid pKChiA or the plasmid pMChiA,with the amount of production were higher 1～3 fold than that produced by the strains carrying the plasmid pLCHIA.