2.4 Site-Directed Mutagenesis PCR
The plasmid pXMJ19-pdsi was used as amplification template to
construct the SI mutants by using overlap extension PCR. Primers used
are listed in Table S2. Final amplification fragments were digested by
the endonuclease Dpn I at 37℃ for 1h, then the PCR mixture was
chemically transformed into competent cells of E. coli JM109. The
sequenced plasmids were transformed into C. glutamium 13032 by
electroporation for protein expression.