HYPERBLEBBING BACTERIAL STRAINS AND USE THEREOF FOR PRODUCTION OF VACCINES

摘要

The present invention relates to the field genetically-engineered Gram- negative bacterial strains that have improved outer-membrane vesicle sheddin g properties, and vaccine compositions comprising these bacteria or vesicles. The present invention provides a hyperbledding Gram-negative bacterium which has been genetically modified by either or both processes selected from a group of consisting of: down-regulation of expression of one or more tol genes; and mutation of one or more gene(s) encoding a protein comprising a peptidoglycan-associated site to attenuate the peptidoglycan-binding activit y of the protein(s).