title: Inactivation of DNA-polymerase associated with hepatitis B virus.
abstract: The effects of heat, sodium hypochlorite, diethyl ether, and ethyl alcohol on the activity of DNA polymerase (DNA-P) associated with hepatitis B virsus (HBV) in serum were evaluated. The response of DNA-P to heating at 60 degrees C for 15, 30, 45, 60, 90, 120, 180, and 240 minutes was studied and the data suggested that there may be two types of DNA-P. The majority of DNA-P was type 'a', and it showed a one log reduction (D60) at 60 degrees C in 36 minutes, while the remaining activity was type 'b' that showed a one log reduction (D60) in 340 minutes. Treatment of DNA-P with sodium hypochlorite at concentrations of 250 and 500 parts per million (ppm) of available chlorine resulted in a 20 to 25% reduction in DNA-P activity within one minute. Complete loss in detectable DNA-P activity occurred within one minute when available Cl- was 2500 ppm or greater. Various concentrations of ethyl alcohol (ranging from 10 to 70%) caused gradually increasing inactivation of DNA-P activity in ten minutes at 4 degrees C. Ninety percent inactivation occurred with 60% alcohol. Overnight treatment of DNA-P-reactive material with diethyl ether at 4 degrees C led to loss of detectable activity. A reduction in the titer of HBsAg was found following treatment with alcohol or ether. The possible use of DNA-P assay as an indicator of the rate of inactivation of HBV is proposed.
mesh_terms: D004259:DNA-Directed DNA Polymerase / Q000032:analysis; D000431:Ethanol / Q000494:pharmacology; D004986:Ether / Q000494:pharmacology; D006515:Hepatitis B virus / Q000187:drug effects / Q000201:enzymology*; D006358:Hot Temperature; D006801:Humans; D019384:Nucleic Acid Synthesis Inhibitors; D012973:Sodium Hypochlorite / Q000494:pharmacology
chemical_list: D019384:Nucleic Acid Synthesis Inhibitors; D004986:Ether; D000431:Ethanol; D012973:Sodium Hypochlorite; D004259:DNA-Directed DNA Polymerase