Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Effect of captan on the exonuclease activities of DNA polymerase I from E. coli and reverse transcriptase from avian myeloblastosis virus

Thesis/Dissertation ·
OSTI ID:5243716
The DNA pol I polymerase activity is known to be inhibited by captan. When captan was tested for its ability to alter the exonuclease activity of DNA pol I, degradation was enhanced at high substrate concentrations. At low concentrations of DNA, captan was inhibitory. By assaying the two exonuclease activities separately it was shown that the differential effect by captan was the result of a combined inhibition of the 3' ..-->.. 5' exonuclease and enhancement of the 5' ..-->.. 3' exonuclease. Studies employing (/sup 14/C) captan showed that the alterations in DNA pol I activities were a result of the irreversible binding of captan to the enzyme in a ratio of 1:1. The effect of captan on AMV reverse transcriptase RNase H activity was also studied. RNase H activity appeared to be more sensitive to captan than was the polymerase activity. Inhibition of the polymerase activity could be prevented by deoxynucleotide triphosphate and was increased by templateprimer. RNase H activity, which showed a sigmoidal relationship between activity and substrate concentration, decreased in V/sub max/ with no change in the Hill coefficient in the presence of captan
Research Organization:
Nevada Univ., Reno (USA)
OSTI ID:
5243716
Country of Publication:
United States
Language:
English