title: Heparin structure and interactions with basic fibroblast growth factor.
abstract: Crystal structures of heparin-derived tetra- and hexasaccharides complexed with basic fibroblast growth factor (bFGF) were determined at resolutions of 1.9 and 2.2 angstroms, respectively. The heparin structure may be approximated as a helical polymer with a disaccharide rotation of 174 degrees and a translation of 8.6 angstroms along the helix axis. Both molecules bound similarly to a region of the bFGF surface containing residues asparagine-28, arginine-121, lysine-126, and glutamine-135, the hexasaccharide also interacted with an additional binding site formed by lysine-27, asparagine-102, and lysine-136. No significant conformational change in bFGF occurred upon heparin oligosaccharide binding, which suggests that heparin primarily serves to juxtapose components of the FGF signal transduction pathway.
authors.affiliation: Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, CA 91125, USA.
authors.forename: S
authors.initials: S
authors.lastname: Faham
authors.forename: R E
authors.initials: RE
authors.lastname: Hileman
authors.forename: J R
authors.initials: JR
authors.lastname: Fromm
authors.forename: R J
authors.initials: RJ
authors.lastname: Linhardt
authors.forename: D C
authors.initials: DC
authors.lastname: Rees
mesh_terms: D001665:Binding Sites; D002236:Carbohydrate Conformation; D002240:Carbohydrate Sequence; D003460:Crystallization; D018360:Crystallography, X-Ray; D016222:Fibroblast Growth Factor 2 / Q000378:metabolism*; D006493:Heparin / Q000737:chemistry* / Q000378:metabolism; D006860:Hydrogen Bonding; D008958:Models, Molecular; D008969:Molecular Sequence Data; D009844:Oligosaccharides / Q000737:chemistry / Q000378:metabolism; D011487:Protein Conformation
chemical_list: D009844:Oligosaccharides; D016222:Fibroblast Growth Factor 2; D006493:Heparin