In order to replicate viruses must invade and hijack host cell mechanisms. One of the most important processes that must be hijacked is the cell death pathways including apoptosis. The herpes viridae have evolved to mimic specific cellular proteins including those in the Bcl-2 family, which are responsible for regulation of the intrinsic apoptotic pathway. Human Herpes virus 8 is a γ- herpesviruses that in healthy individuals is normally kept supressed by the immune system. If the infected individual becomes immune compromised, as in AIDS patients or cancer patients undergoing chemotherapy, the virus can cause Castlemans disease, Primary Efflusion lymphoma and Kaposi sarcoma, all of which are characterised by the presence of tumours.

Encoded in the HHV8 genome is a structural homolog of cellular Bcl-2, Kaposi Sarcoma Bcl-2 (KsBcl-2), which shows significant structurally homology to Bcl-2 despite having low sequence identity.To date KsBcl-2’s functional mechanism and its potential role intumourigenesis remains poorly understood, so we embarked on adetailed structural analysis of its anti-apoptotic activity. We showthat KsBCl-2 can bind BH3 family members such as Bim, Bak andBax and has potent anti-apoptotic effects in against Bax and Bak inyeast. We have obtained crystals for KsBcl-2 in complex with Bak,Bax and Bim BH3 peptides and we have obtained diffraction datasets for Se-Met labelled protein.