Preparation and characterization of E.coli “bacterial ghost” / 解放军医学杂志

ABSTRACT

Objective To prepare the “bacterial ghost” of E.coli with heat-induction and analyse its lysis rate and configuration. Methods Through immediately shifting the culture temperature from 37℃ to 42℃, E.coli DH5? including plasmid pMuH36 was induced to lyse, and the OD value of culture media was measured every 30 minutes during the induction. After 4 hours of induction, the bacteria samples were collected to examine the lysis rate by CFU (colony formation unit) and the configuration of lysed bacteria was observed by transmission electron microscopy (TEM). Results The OD value of DH5? (pMuH36)began to decline after 1 hour of induction, and increased slowly after 4 hours of induction. The CFU assay showed that the lysis rate was about 95%. TEM observation proved that most of the lysed bacteria were emptied, whereas the whole outmembrane structure, i.e. “bacterial ghost”, remained. Conclusions The E.coli “bacterial ghost” was efficiently prepared and identified, which might provide the basis for further development of a more effective “bacterial ghost” vaccine and adjuvant.