Illustration of the I73R protein from the African swine fever virus (ASFV). The protein binds to Z-DNA (Z-deoxyribonucleic acid) a form of DNA that winds to the left as opposed to the more common right-handed form. Z-DNA-binding proteins have been shown to be vital for pathogenicity of viruses and are therefore a target for drugs and vaccines. African swine fever is a haemorrhagic fever in pigs that has a high mortality rate. It is highly contagious and infections cause huge losses in the swine industry.