title: Site-specific mutagenesis of annexin V: role of residues from Arg-200 to Lys-207 in phospholipid binding.
abstract: Annexin V (placental anticoagulant protein I) binds tightly to anionic phospholipid vesicles in the presence of calcium. Four mutant proteins were expressed in Escherichia coli in which Ala replaced one of the following residues in the third repeat of annexin V: Arg-200, His-204, Arg-206, or Lys-207. In a competitive fluorescence quenching assay, the wild-type recombinant protein had the same affinity for phosphatidylserine-containing vesicles as the placentally derived protein. The affinity of the four mutant proteins for phosphatidylserine-containing vesicles was unchanged relative to wild-type protein. We conclude that His-204 and adjacent basic residues, including the highly conserved Arg-200 residue, are not required for high-affinity phospholipid binding.
authors.affiliation: Department of Laboratory Medicine, University of Washington, Seattle 98195.
authors.forename: J F
authors.initials: JF
authors.lastname: Tait
authors.forename: C
authors.initials: C
authors.lastname: Smith
mesh_terms: D000595:Amino Acid Sequence; D017304:Annexin A5; D001483:Base Sequence; D001665:Binding Sites; D001667:Binding, Competitive; D002135:Calcium-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D004247:DNA / Q000235:genetics; D005260:Female; D006801:Humans; D008969:Molecular Sequence Data; D016297:Mutagenesis, Site-Directed; D010743:Phospholipids / Q000378:metabolism; D011247:Pregnancy; D011257:Pregnancy Proteins / Q000235:genetics* / Q000378:metabolism
chemical_list: D017304:Annexin A5; D002135:Calcium-Binding Proteins; D010743:Phospholipids; D011257:Pregnancy Proteins; D004247:DNA