| abstract |
The phoA mutant E. coli SB44, which was shown by mutating E. coli HB 101 with an N-nitroso compound, serves to identify and isolate recombinant plasmids in which a phoA gene is incorporated. These plasmids are used to transform bacteria which, after cloning and incubation, provide alkaline phosphatase in high yield. These plasmid vectors can also be modified in various ways so that the N-terminal amino acid sequence of the phoA DNA follows for some other proteins. These new plasmids can then in turn be used to express fusion proteins in bacteria. |