icles is able to complete the replication cycle. In addition to the inhibition of HIV-1, A3G restricts replication of other lentiviruses, gammaretroviruses, deltaretroviruses, spumaviruses, long-terminal-repeat (LTR)-retrotransposons, orthohepadnaviruses and avihepadnaviruses (9–21). Interestingly, deamination seems not to be the only A3G-mediated antiviral mechanism; in the case of hepatitis B virus (