title: Activities of the feline immunodeficiency virus integrase protein produced in Escherichia coli.
abstract: Retroviral DNA integration requires the activity of at least one viral protein, the integrase (IN) protein. We cloned and expressed the integrase gene of feline immunodeficiency virus (FIV) in Escherichia coli as a fusion to the malE gene and purified the IN fusion protein by affinity chromatography. The protein is active in site-specific cleavage of the viral DNA ends, DNA strand transfer, and disintegration. FIV IN has a relaxed viral DNA substrate requirement: it cleaves and integrates FIV DNA termini, human immunodeficiency virus DNA ends, and Moloney murine leukemia virus DNA ends with high efficiencies. In the cleavage reaction, IN exposes a specific phosphodiester bond near the viral DNA end to nucleophilic attack. In vitro, either H2O, glycerol, or the 3' OH group of the viral DNA terminus can serve as nucleophile in this reaction. We found that FIV IN preferentially uses the 3' OH ends of the viral DNA as nucleophile, whereas HIV IN protein preferentially uses H2O and glycerol as nucleophiles.
authors.affiliation: Division of Molecular Biology, The Netherlands Cancer Institute, Amsterdam.
authors.forename: C
authors.initials: C
authors.lastname: Vink
authors.forename: K H
authors.initials: KH
authors.lastname: van der Linden
authors.forename: R H
authors.initials: RH
authors.lastname: Plasterk
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D003001:Cloning, Molecular; D004254:DNA Nucleotidyltransferases / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*; D004251:DNA Transposable Elements; D004268:DNA-Binding Proteins / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics; D016089:Immunodeficiency Virus, Feline / Q000201:enzymology*; D019426:Integrases; D008969:Molecular Sequence Data; D011993:Recombinant Fusion Proteins / Q000302:isolation & purification / Q000378:metabolism; D017386:Sequence Homology, Amino Acid; D013379:Substrate Specificity; D016662:Virus Integration / Q000502:physiology
chemical_list: D004251:DNA Transposable Elements; D004268:DNA-Binding Proteins; D011993:Recombinant Fusion Proteins; D004254:DNA Nucleotidyltransferases; D019426:Integrases