Path: utzoo!attcan!uunet!cs.utexas.edu!samsung!usc!ucla-cs!whycare@ATHENA.MIT.EDU
From: whycare@ATHENA.MIT.EDU (Paranoid Schizoid)
Newsgroups: sci.med.aids
Subject: AZT,DDI,and DDC
Message-ID: <34222@shemp.CS.UCLA.EDU>
Date: 13 Apr 90 23:01:44 GMT
Sender: news@CS.UCLA.EDU
Reply-To: whycare@athena.mit.edu (Paranoid Schizoid)
Organization: Massachusetts Institute of Technology
Lines: 21
Approved: ddodell@stjhmc.fidonet.org (David Dodell)
Note:	Copyright 1990 by Daniel R. Greening.  Permission granted for
Note:	non-commercial reproduction.
Archive-number: 1961


 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