Primary binding domain of bovine von Willebrand factor fragment expressed in E. coli.
Bovine vWF cDNA has been cloned from a bovine endothelial cell library. A fragment of this cDNA, corresponding to amino acid sequence Leu 469-Ser 723, called primary adhesion domain (PAD-1), and containing the binding sites for platelet glycoprotein Ib (GPIb), heparin and collagen, has been expressed in E. coli. The reduced and alkylated form of fragment PAD-1 inhibited native vWF binding to GPIb. Fragment PAD-1 bound to heparin and botrocetin in a specific and dose dependent manner as did the native vWF. In a solid-phase assay, fragment PAD-1 bound to calf skin collagen in contrast to a human vWF recombinant fragment (Ser 445-Val 733) which was inactive in the same assay. The studies presented in this paper demonstrated that the A1 domain of bovine vWF contained the GPIb, heparin, botrocetin as well as collagen binding sites and that integrity of the disulfide bond (Cys 509-Cys 695), did not seem to be essential for binding of bovine vWF fragment to GPIb.
Bakhshi
M R
MR
Department of Biochemistry, Temple University School of Medicine, Philadelphia, PA 19140, USA.
Sinha
D
D
Vora
R K
RK
Budzynski
A Z
AZ
Kirby
E P
EP
D000595:Amino Acid Sequence; D000818:Animals; D001665:Binding Sites; D001792:Blood Platelets / Q000187:drug effects; D002417:Cattle; D004926:Escherichia coli; D008969:Molecular Sequence Data; D017434:Protein Structure, Tertiary; D011869:Radioligand Assay; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000737:chemistry; D014841:von Willebrand Factor / Q000737:chemistry*
D011994:Recombinant Proteins; D014841:von Willebrand Factor