Enzyme activity gel analysis of human immunodeficiency virus reverse transcriptase.

An activity gel analysis was performed in order to examine the catalytically active component of human immunodeficiency virus (HIV) reverse transcriptase in purified enzyme preparations and HIV-infected cell extracts. Immunoaffinity purified HIV reverse transcriptase contains two proteins with molecular weights 66,000 and 51,000 in approximately equal proportions. After denaturing polyacrylamide gel electrophoresis and removal of sodium dodecyl sulfate, the p66 component of reverse transcriptase was sufficient for both DNA- and RNA-directed DNA synthesis. No DNA synthetic activity of p51 was observed. Recovery of p66 catalytic activity was approximately 10% that of DNA polymerase beta, and the density of the autoradiographic band corresponding to p66 was linear with enzyme concentration. No additional HIV-specific DNA polymerases besides p66 were observed in HIV-infected H9 cell extracts.