Abstract: The invention related to an isolated plasmid encoding a bacterial VapBC toxin-antitoxin system, wherein the VapBC toxin-antitoxin system comprises a modified VapB amino acid sequence arranged to increase the maintenance of the plasmid in a bacterial host, wherein the modification to VapB comprises or consists of a substitution of at least one of Q12, F6, F51 and F60 residues relative to Shigella sonnei wild-type VapB or Shigella flexneri wild-type VapB, or structurally equivalent residues of Shigella sonnei wild-type VapB or Shigella flexneri wild-type VapB in a homologue thereof; and associated methods, uses and host cells.

Abstract: The invention relates to a modified V2 fHbp having increased stability over a wild type V2 fHbp; a modified V2 fHbp having an amino acid sequence with at least 85% identity to the sequence of Seq ID No: 1, wherein both Ser137 and Gly138 are mutated or both Val112 and Leu114 are mutated; immunogenic, pharmaceutical and vaccine compositions; nucleic acid and a host cell; and methods of use of such compositions.

Abstract: The invention relates to a modified V2 fHbp having increased stability over a wild type V2 fHbp; a modified V2 fHbp having an amino acid sequence with at least 85% identity to the sequence of Seq ID No: 1, wherein both Ser137 and Gly138 are mutated or both Val112 and Leu114 are mutated; immunogenic, pharmaceutical and vaccine compositions; nucleic acid and a host cell; and methods of use of such compositions.

Abstract: The present invention relates to an immunogenic composition comprising at least one modified factor H binding protein, wherein the composition is capable of eliciting an immune response, when administered to a human or non-human animal; and associated compositions, uses and kits.

Abstract: A series of genes from Neisseria meningitidis are shown to encode products which are implicated in virulence. The identification of these genes therefore allows attenuated microorganisms to be produced. Furthermore, the genes or their encoded products can be used in the manufacture of vaccines for therapeutic application.

Abstract: A method for identifying a polypeptide of a microorganism which polypeptide is associated with an immune response in an animal which has been subjected to the microorganism, the method comprising the steps of (1) providing a plurality of different mutants of the microorganism; (2) contacting the plurality of mutant microorganisms with antibodies from an animal which has raised an immune response to the microorganism or a part thereof, under conditions whereby if the antibodies bind to the mutant microorganism the mutant microorganism is killed; (3) selecting surviving mutant microorganisms from step (2); (4) identifying the gene containing the mutation in any surviving mutant microorganism; and (5) identifying the polypeptide encoded by the gene. The polypeptide identified or a variant or fragment thereof or a fusion of these is useful in a vaccine.

Abstract: A series of genes from Neisseria meningitidis are shown to encode products which are implicated in virulence. The identification of these genes therefore allows attenuated microorganisms to be produced. Furthermore, the genes or their encoded products can be used in the manufacture of vaccines for therapeutic application.

Abstract: A series of genes form Neisseria meningitidis are shown to encode products which are responsible for DNA uptake. The identification of these genes therefore allows attenuated microorganisms to be produced that have a reduced ability to take up DNA. Microorganisms of the invention may be used in the production of genetically stable mutant microorganisms. The genes or their encoded products can be used in the manufacture of vaccines for therapeutic application.