title: Solution structure of the I gamma subdomain of the Mu end DNA-binding domain of phage Mu transposase.
abstract: The MuA transposase of phase Mu is a large modular protein that plays a central role in transposition. We show that the Mu end DNA-binding domain, I beta gamma, which is responsible for binding the DNA attachment sites at each end of the Mu genome, comprises two subdomains, I beta and I gamma, that are structurally autonomous and do not interact with each other in the absence of DNA. The solution structure of the I gamma subdomain has been determined by multidimensional NMR spectroscopy. The structure of I gamma comprises a four helix bundle and, despite the absence of any significant sequence identity, the topology of the first three helices is very similar to that of the homeodomain family of helix-turn-helix DNA-binding proteins. The helix-turn-helix motif of I gamma, however, differs from that of the homeodomains in so far as the loop is longer and the second helix is shorter, reminiscent of that in the POU-specific domain.
authors.affiliation: Laboratory of Chemical Physics, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892-0520, USA.
authors.forename: R T
authors.initials: RT
authors.lastname: Clubb
authors.forename: S
authors.initials: S
authors.lastname: Schumacher
authors.forename: K
authors.initials: K
authors.lastname: Mizuuchi
authors.forename: A M
authors.initials: AM
authors.lastname: Gronenborn
authors.forename: G M
authors.initials: GM
authors.lastname: Clore
mesh_terms: D000595:Amino Acid Sequence; D010583:Bacteriophage mu / Q000201:enzymology*; D004279:DNA, Viral / Q000378:metabolism*; D004926:Escherichia coli / Q000235:genetics; D015870:Gene Expression / Q000235:genetics; D019077:Helix-Turn-Helix Motifs; D018398:Homeodomain Proteins / Q000737:chemistry / Q000235:genetics; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed / Q000235:genetics; D017433:Protein Structure, Secondary; D011994:Recombinant Proteins / Q000737:chemistry; D017384:Sequence Deletion / Q000235:genetics; D019895:Transposases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism
chemical_list: D004279:DNA, Viral; D018398:Homeodomain Proteins; D011994:Recombinant Proteins; D019895:Transposases