title: Development and evaluation of a structural model for SF1B helicase Dda.
abstract: Helicases are proteins that unwind double-stranded nucleic acids. Dda helicase from bacteriophage T4 has served as an excellent model for understanding the molecular mechanism of this class of enzymes. Study of the structure of Dda may reveal why some helicases translocate in a 5' to 3' direction on DNA, while others translocate in a 3' to 5' direction. Attaining a structure of Dda has proven difficult because the protein fails to readily form crystals and is too large for current NMR technologies. We have developed a homology model of the enzyme which will serve to guide studies that examine the structural and functional significance of the interaction between Dda and DNA and how this interaction affects translocation and unwinding of DNA. We have tested the structural model by using methods for mapping protein domains and for examining protein surfaces that interact with DNA.
authors.affiliation: Department of Biochemistry and Molecular Biology, University of Arkansas for Medical Sciences, Little Rock, Arkansas 72205, USA.
authors.forename: Lauren P
authors.initials: LP
authors.lastname: Blair
authors.forename: Alan J
authors.initials: AJ
authors.lastname: Tackett
authors.forename: Kevin D
authors.initials: KD
authors.lastname: Raney
mesh_terms: D000595:Amino Acid Sequence; D017122:Bacteriophage T4 / Q000737:chemistry / Q000201:enzymology* / Q000235:genetics; D004247:DNA / Q000737:chemistry / Q000378:metabolism; D004265:DNA Helicases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D008958:Models, Molecular; D008968:Molecular Conformation; D008969:Molecular Sequence Data; D011485:Protein Binding; D016415:Sequence Alignment; D014764:Viral Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism
chemical_list: D014764:Viral Proteins; D004247:DNA; D004265:DNA Helicases