title: Arm site independence of coliphage HK022 integrase in human cells.
abstract: The integrase encoded by the lambdoid phage HK022 (Int-HK022) resembles its coliphage λ counterpart (Int-λ) in the roles of the cognate DNA arm binding sites and in controlling the direction of the reaction. We show here that within mammalian cells, Int-HK022 does not exhibit such a control. Rather, Int-HK022 recombined between all ten possible pairwise att site combinations, including attB × attB that was more effective than the conventional integrative attP × attB reaction. We further show that Int-HK022 depends on the accessory integration host factor (IHF) protein considerably less than Int-λ and exhibits stronger binding affinity to the att core. These differences explain why wild-type Int-HK022 is active in mammalian cells whereas Int-λ is active there only as an IHF-independent mutant.
authors: Department of Biochemistry and Molecular Biology, Tel-Aviv University, 69978 Tel-Aviv, Israel.
authors: Natalia
authors: N
authors: Malchin
authors: Chen N
authors: CN
authors: Tuby
authors: Ezra
authors: E
authors: Yagil
authors: Mikhail
authors: M
authors: Kolot
mesh_terms: D025523:Bacteriophage HK022 / Q000201:enzymology* / Q000235:genetics*; D010582:Bacteriophage lambda / Q000201:enzymology / Q000235:genetics; D004926:Escherichia coli / Q000821:virology; D006801:Humans; D019426:Integrases / Q000235:genetics*; D011995:Recombination, Genetic; D014764:Viral Proteins / Q000235:genetics; D016662:Virus Integration
chemical_list: D014764:Viral Proteins; D019426:Integrases