摘要：The citrate permease determinant (Cit-P) in Lactococcus lactis subsp. lactis biovar. diacetylactis MAD61 (L. diacetylactis) was demonstrated to be encoded by a 8.4 kb plasmid, pMC8, by protoplast induced plasmid curing experiments, The 1.9 kb Cit-P gene fragment was cloned into the Hindlll / Pstl site of plasmid pNZ9019. Resulting recombinant plasmid, pNZ9020, enabled Escherichia CO//E10-1 and citrate permease negative (Cit-P-) L diacetylactis MAD61 -22 to transport and utilize citrate, indicating expression of the citrate permease from strain MAD61 to interspecific and itraspecific hosts.
