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.