Channel forming proteins called porins are found in large quantities in the outer membrane of Gram-negative bacteria, along with phospholipids, lipopolysaccharides, lipoproteins and other integral membrane proteins. A specific porin from Neisserial species, PorB, is highly abundant on outer membrane and usually facilitates the uptake of small nutrient molecules; however it is also associated with pathogenesis. These porins are enriched on neisserial blebs. Structurally, PorB can be characterized as a 16 stranded beta-barrel protein that forms trimers. It also shares several features with the mitochondrial voltage-dependent anion channel (VDAC), which is suggested to play a role in host cell apoptosis. An interaction between the two proteins has also been suggested to occur during Neisserial pathogenesis. It is also now known that PorB is highly abundant on/in outer membrane vesicles (OMVs) secreted by Neisserial Spp. During infection PorB localizes to host mitochondria, however the molecular mechanisms of the translocation events from the bacteria and into host cells is not understood

 We have established a controllable expression system for the synthesis of PorB in host cells. With this system, in combination with infection assays with Neisseria gonorrhoeae secreted protein extracts. We are trying to study the targeting and the impact of PorB on host cell mitochondrial function and overall cell viability. We are also investigating, whether OMVs are a major secretion system for a pathogenic form of PorB, and whether other virulence factors in Neisserial OMVs also target host cells.