Preincubation of recombinant Ipa proteins of Shigella sonnei promotes entry of non-invasive Escherichia coli into HeLa cells.
Invasion plasmid antigens of Shigella sonnei, IpaB, C, D, were expressed as fusion proteins either with maltose-binding protein (MBP) or Strept-tag sequence. Affinity-purified IpaB and IpaD were separated from MBP by digestion with Factor Xa. Recombinant IpaC having Strept-tag sequence at its C-terminal was also purified by avidin affinity column chromatography. These recombinant proteins showed the ability to cause non-invasive Escherichia coli K-12 to internalize HeLa cell only when all of the proteins were preincubated with the bacterial prior to the inoculation of the mixture into HeLa cell culture. Electron microscopy also showed internalized bacteria within HeLa cells suggesting that functional complex of invasins (IpaB, C and D) were formed in vitro.
Terajima
J
J
Department of Bacteriology, National Institute of Infectious Diseases, Toyama 1-23-1 Shinjuku, Tokyo, 162-8640, Japan.
Moriishi
E
E
Kurata
T
T
Watanabe
H
H
D000942:Antigens, Bacterial / Q000096:biosynthesis / Q000302:isolation & purification / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000378:metabolism / Q000494:pharmacology*; D015153:Blotting, Western; D004926:Escherichia coli / Q000187:drug effects* / Q000378:metabolism; D006367:HeLa Cells / Q000382:microbiology; D006801:Humans; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000494:pharmacology; D012764:Shigella sonnei / Q000378:metabolism / Q000472:pathogenicity*; D016622:Silver Staining; D014774:Virulence
D000942:Antigens, Bacterial; D001426:Bacterial Proteins; C095770:IpaD protein, Shigella flexneri; D011994:Recombinant Proteins; C087447:ipaB protein, Shigella; C092342:IpaC protein, Shigella