CHEM 112 Lecture Notes - Epitope, Drug Resistance, Macrophage

• School: Queen's University
• Department: Chemistry
• Course: CHEM 112
• Professor: Richard Ascough

Document Summary

O because thousands of generations of hiv replication take place within each patient during the course of an infection, a single strain of hiv can produce hundreds of different reverse transcriptase variants over time. Because of their large numbers, it is a virtual certainty that one or more of these variants contains an amino acid substitution that lessens reverse transcriptase"s affinity for azt. Furthermore, each new generation in the viral population is likely to contain virions with additional new mutations. Some of these additional mutations may further enhance the ability of reverse transcriptase to function in the presence of azt. Because they reproduce faster, the virions that carry these new mutations will also increase in frequency at the expense of their less- resistant contemporaries. Process of change over time in the composition of the viral population is called evolution by natural selection. Changes in the genetic makeup of hiv populations over time have led to increased drug resistance.