| Abstract |
A modified C. coli trp operon, trpL(Δatt)trpE^FBR, was conjugally transfered into Klebsiella pneumoniae KC 100 (Phe^-, Tyr^-, Trp^-, Rif^r, Kam^r) by in vivo cloning using the hybrid plasmid R_6K:: Mucts 61 with a transfer frequency of 5.2×10^-7. Two K. pneumoniae transconjugants, KUA701 and KUA702, were isolated. The characters of attenuation control-free and resistance to feedback-inhibition which are characteristics of donor C. coli trp operon were normally expressed in the KUA 701. However, KUA 702 retained only the feedback-inhibition resistant character. Trp^+ phenotype and ampicillin resistant character were completely stable in the transconjugants, but streptomycin resistant character was lost in the transconjugants. |
