IMMUNOGENIC BACTERIAL VESICLES WITH OUTER MEMBRANE PROTEINS

摘要

Knockout of the meningococcal mltA homolog gives bacteria that spontaneously release vesicles that are rich in immunogenic outer membrane proteins and th at can elicit cross-protective antibody responses with higher bactericidal titr es than OMVs prepared by normal production processes. Thus the invention provid es a bacterium having a knockout mutation of its mltA gene. The invention also provides a bacterium, wherein the bacterium: (i) has a cell wall that includ es peptidoglycan; and (ii) does not express a protein having the lytic transglycosylase activity of MltA protein. The invention also provides compositions comprising vesicles that, during culture of bacteria of the invention, are released into the culture medium.