Development of a protein secretion system with the application of sec-dependent protein secretion components.

摘要: In order to induce high levels of protein secretion, we have constructed a recombinant plasmid, designated pBP244, into which was incorporated key components the type-II Sec-dependent secretion system, including LepB (signal peptidase), SecA (ATPase), and SecB (chaperone). The biological activities LepB, SecA, expressed from genes harbored by pBP244 appeared play their normal roles. evaluate pspA (Streptococcus pneumoniae surface A) gene cloned resulting in pBP438. S. typhimurium harboring pBP438 grown until stationary phase, secreted higher level PspA culture supernatants than did strain pYA3494. supernatant amount 1.71-fold, periplasmic space 1.47-fold, an outer membrane 1.49-fold that chi8554 kept Asd+ plasmid for 60 generations LB broth DAP, thereby indicating were quite stable Salmonella strain.