Cloning and analyzing of prokaryotic expression of four exoenzyme genes from potato soft-rot pathogen Erwinia carotovora subsp. carotovora 71

In the present study,the virulence genes pel,peh,cel and prt of Erwinia carotovora subsp.carotovora 71 (Ecc71) which was the main pathogens of potato soft-rot were cloned by homologous cloning techniques.The sequences and predicted gene products were analyzed with bioinformatics.These four genes were cloned into the prokaryotic expression vector pET28a.The successful recombinant vectors pET28a-pel,pET28a-peh,pET28a-cel and pET28a-prt were transformed into E.coli BL21 (DE3) respectively.The expression products of pel and peh genes were analyzed by SDS-PAGE and enzyme activities were also analyzed.The specific proteins with same molecular weights with deduced proteins from studied genes were observed and the enzyme activity was 1.672 U·mL-1·h-1,0.024,112.7 and 16.95 U·mL-1·min-1,respectively.The results provided foundation for exploring the interaction between these four enzymes and the disease-resistance of the potato soft-rot.