Details of this research, the first isolation of a fully active protease from an endogenous virus gene, appear in the December 8 edition of the peer-reviewed journal Biochemistry, published by the American Chemical Society, the world's largest scientific society. Why they have been preserved in humans is unclear and no infectious viral particles have been discovered to date. But the gene portions can apparently make viral parts. A protease is like a pair of protein scissors. HIV-1's genetic machinery churns out long protein chains from which its protease makes specific cuts to create functional parts.
Protease inhibitors block the cutting.
But, even in the presence of multiple inhibitors, HIV-1 often seems to find a way to get the job done. This is due, at least in part, to the virus developing mutations that make the protease resistant to multiple drugs. It is possible that resistance is not due entirely to mutations, say the scientists. If so, future AIDS treatments may need to be developed for yet another target. The hypothesis is a little bit on the fringe, but we have had some surprising results that support it.