whycare@ATHENA.MIT.EDU (Paranoid Schizoid) (04/14/90)
In his article, "Re: DDI + AZT," dgreen@squid.cs.ucla.edu states: >AZT, DDI, and DDC form a complementary family of drugs. They interfere (if I >remember this right) with AIDS protein-synthesis by substituting for different >critical amino-acids. The drugs do interfere with AIDS protein-synthesis, but they DO NOT substitute for amino acids. Instead, the drugs block the synthesis of the viral DNA intermediate (HIV is an RNA virus) by substituting for the normal DNA bases. The enzyme (DNA polymerase) that catalyzes the linkage between the base pairs can't work on the substituted bases because the configuration isn't precisely correct (3'OH on the normal bases are substituted for something else). So the DNA just stops getting synthesized at certain points. If the DNA isn't synthesized correctly, the correct viral proteins can't be synthesized because the mRNA (the molecule that is actually read into protein) gets messed up. That means the virus goes out of business. (That's how it's supposed to work theoretically.) whycare@athena.mit.edu