Abstract: The invention relates to nucleic acid molecules which code proteins which mediate the adhesion of bacteria from the genus Neisseria to human cells. It also relates to the proteins coded by these nucleic acid molecules and antibodies against said proteins, and to drugs, vaccines and diagnostic compositions which contain the nucleic acid molecules, proteins and/or antibodies.

Abstract: The present invention concerns an adherence gene from Helicobacter pylori, a polypeptide coded thereby and antibodies against the polypeptide.

Abstract: The present invention relates to bacteria for preparing stable fusion prons from a carrier protein and a passenger protein, the bacteria possessing the genetic marker fpt. This genetic marker permits the improved preparation of protein fusions having a destabilizing effect on bacteria. The present invention in particular relates to bacteria for preparing fusion proteins, the bacteria stably presenting the fusion proteins on their surface and possessing the markers ompT.sup.-- and dsbA.sup.-- in addition to the genetic marker fpt. Moreover, the present invention relates to the identification of bacteria, which present heterologous proteins having an affinity to a binding partner on its surface and methods for constructing vectors encoding these proteins. Finally, the present invention also relates to bacteria which stably present at least one fusion protein on their surface and possess the genetic markers fpt, ompT.sup.-- and dsbA.sup.--, and their use for instance for diagnostic purposes.

Abstract: For the enzymatic cleavage of fusion proteins and for the isolation of deed components of these fusion proteins(1) a junction region, in which two components of the fusion protein are joined together, is modified by means of genetic engineering so that at least one IgA protease recognition site with the amino acid sequence Y-Pro.!.X-Pro is formed in this junction region, in which X can be any amino acid and Y can be one or several arbitrary amino acids,(2) the fusion protein which results from step (1) is cleaved by IgA protease at the position in the recognition site marked with .!. and(3) after the cleavage one or several desired components of the fusion protein are isolated.

Abstract: For the gene-technological production of proteins, a vector is introduced to gram-negative host cells which contains at least one gene coding translated. For the extracellular obtaining of the proteins its coding gene is so inserted into a vector which contains the IgA-protease precursor gene from micro-organisms of the genus Neisseria that the coding gene is positioned within the sequence of the IgA-protease precursor gene. A plasmid especially suitable for this purpose is the plasmid pIP100 contained in E. coli DSM 3775.