       Document 0695
 DOCN  M9590695
 TI    Characterization of mg2+ - dependent endonucleolytic activity and
       development of a fluorescence assay for hiv-1 integrase in vitro.
 DT    9509
 AU    Lee SP; Kim HG; Censullo ML; Knutson JR; Han MK; Georgetown University
       Medical Center, Department of Biochemistry,; Washington, DC
 SO    NIH Conf Retroviral Integrase. 1995 Jan 19-20;:(Participants' abstracts
       and posters, abstract no. 5). Unique Identifier : AIDSLINE AIDS/95920024
 AB    In vitro reactions of Human Immunodeficiency Virus-1 Integrase (HIV-IN)
       performed with short oligonucleotide substrates show a preference for
       Mn2+ as the catalytic cofactor. In contrast, studies with infected cell
       extracts show that viral DNA integration occurs in the presence of Mg2+.
       We report that changes in the structure and length of the
       oligonucleotide substrates alter the donor processing activity of HIV-IN
       to a Mg2+-dependent activity, thereby bringing both the in vivo and in
       vitro reactions into agreement. Furthermore, a novel mechanism
       (alternative disintegration) catalyzed by the endonuclease activity of
       HIV-IN is responsible for cleaving the junction between the viral and
       target sequences of the intermediate without rejoining the target
       strands. The Mg2+-dependent donor processing activity allows for the
       development of a rapid and continuous fluorescence assay for HIV-IN
       based on fluorescence resonance energy transfer (FRET). Steady-state
       fluorescence studies indicate the fluorescence cleavage assay monitored
       by the enhancement of the donor fluorescence is consistent with data
       obtained from the radioactive assay. This fluorescence assay will
       facilitate both detailed kinetic studies and rapid screening of HIV-1
       integrase inhibitors.
 DE    DNA Nucleotidyltransferases/*ANTAGONISTS & INHIB  DNA,
       Complementary/GENETICS  DNA, Viral/GENETICS  HIV-1/*ENZYMOLOGY
       Immunodeficiency Virus, Feline/ENZYMOLOGY  Leukemia Viruses,
       Murine/ENZYMOLOGY  Oligopeptides/*PHARMACOLOGY  Virus
       Integration/GENETICS  MEETING ABSTRACT

       SOURCE: National Library of Medicine.  NOTICE: This material may be
       protected by Copyright Law (Title 17, U.S.Code).

