The Biology Project: Biochemistry

Metabolism Problem Set

Problem 6: Lactic Acid Production


A new drug was found to decrease Hepatitis B virus. The drug is an analogue of one of the nucleic acid bases of DNA and probably works by being incorporated into the virus and disrupting viral genes during viral DNA replication. However, patients in a clinical trial of the drug began to experience drastic overproduction of lactic acid and liver failure leading to death. The most likely explanation for the problem:

A. Incorporation of the drug into mitochondrial DNA disrupts the ability of mitochondria to make ATP.
The key concept is that lactic acid is produced only when there is exertion for the muscles or when mitochondrial function is inhibited. The drastic overproduction of lactic acid and liver failure due to a drug that acts like a nucleotide would only occur if this analogue was incorporated into mitochondrial DNA, disrupting mitochondria function. Tragically, that is exactly what happened in this case.
B. The virus with mutations must overproduce lactic acid.

The Biology Project
University of Arizona
Tuesday, August 20, 1996
Contact the Development Team
All contents copyright © 1996. All rights reserved.