Biomaterial Database

Structure of the integrin alpha2beta1-binding collagen peptide. 2004

Jonas Emsley, and C Graham Knight, and Richard W Farndale, and Michael J Barnes

Department of Biochemistry, University of Leicester LE17RH, Leicester, UK. je14@le.ac.uk

We have determined the 1.8A crystal structure of a triple helical integrin-binding collagen peptide (IBP) with sequence (Gly-Pro-Hyp)(2)-Gly-Phe-Hyp-Gly-Glu-Arg-(Gly-Pro-Hyp)(3). The central GFOGER hexapeptide is recognised specifically by the integrins alpha2beta1, alpha1beta1, alpha10beta1 and alpha11beta1. These integrin/collagen interactions are implicated in a number of key physiological processes including cell adhesion, cell growth and differentiation, and pathological states such as thrombosis and tumour metastasis. Comparison of the IBP structure with the previously determined structure of an identical collagen peptide in complex with the integrin alpha2-I domain (IBP(c)) allows the first detailed examination of collagen in a bound and an unbound state. The IBP structure shows a direct and a water-mediated electrostatic interaction between Glu and Arg side-chains from adjacent strands, but no intra-strand interactions. The interactions between IBP Glu and Arg side-chains are disrupted upon integrin binding. A comparison of IBP and IBP(c) main-chain conformation reveals the flexible nature of the triple helix backbone in the imino-poor GFOGER region. This flexibility could be important to the integrin-collagen interaction and provides a possible explanation for the unique orientation of the three GFOGER strands observed in the integrin-IBP(c) complex crystal structure.

UI	MeSH Term	Description	Entries
D008958	Models, Molecular	Models used experimentally or theoretically to study molecular shape, electronic properties, or interactions; includes analogous molecules, computer-generated graphics, and mechanical structures.	Molecular Models,Model, Molecular,Molecular Model
D010455	Peptides	Members of the class of compounds composed of AMINO ACIDS joined together by peptide bonds between adjacent amino acids into linear, branched or cyclical structures. OLIGOPEPTIDES are composed of approximately 2-12 amino acids. Polypeptides are composed of approximately 13 or more amino acids. PROTEINS are considered to be larger versions of peptides that can form into complex structures such as ENZYMES and RECEPTORS.	Peptide,Polypeptide,Polypeptides
D002448	Cell Adhesion	Adherence of cells to surfaces or to other cells.	Adhesion, Cell,Adhesions, Cell,Cell Adhesions
D003094	Collagen	A polypeptide substance comprising about one third of the total protein in mammalian organisms. It is the main constituent of SKIN; CONNECTIVE TISSUE; and the organic substance of bones (BONE AND BONES) and teeth (TOOTH).	Avicon,Avitene,Collagen Felt,Collagen Fleece,Collagenfleece,Collastat,Dermodress,Microfibril Collagen Hemostat,Pangen,Zyderm,alpha-Collagen,Collagen Hemostat, Microfibril,alpha Collagen
D006860	Hydrogen Bonding	A low-energy attractive force between hydrogen and another element. It plays a major role in determining the properties of water, proteins, and other compounds.	Hydrogen Bonds,Bond, Hydrogen,Hydrogen Bond
D000595	Amino Acid Sequence	The order of amino acids as they occur in a polypeptide chain. This is referred to as the primary structure of proteins. It is of fundamental importance in determining PROTEIN CONFORMATION.	Protein Structure, Primary,Amino Acid Sequences,Sequence, Amino Acid,Sequences, Amino Acid,Primary Protein Structure,Primary Protein Structures,Protein Structures, Primary,Structure, Primary Protein,Structures, Primary Protein
D055672	Static Electricity	The accumulation of an electric charge on a object	Electrostatic,Electrostatics,Static Charge,Charge, Static,Charges, Static,Electricity, Static,Static Charges
D018360	Crystallography, X-Ray	The study of crystal structure using X-RAY DIFFRACTION techniques. (McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	X-Ray Crystallography,Crystallography, X Ray,Crystallography, Xray,X Ray Crystallography,Xray Crystallography,Crystallographies, X Ray,X Ray Crystallographies
D018583	Pliability	The quality or state of being able to be bent or creased repeatedly. (From Webster, 3d ed)	Flexibility
D020816	Amino Acid Motifs	Three-dimensional protein structural elements that are composed of a combination of secondary structures. They include HELIX-LOOP-HELIX MOTIFS and ZINC FINGERS. Motifs are typically the most conserved regions of PROTEIN DOMAINS and are critical for domain function. However, the same motif may occur in proteins or enzymes with different functions.	AA Motifs,Motifs, Amino Acid,Protein Motifs,Protein Structure, Supersecondary,Supersecondary Protein Structure,AA Motif,Amino Acid Motif,Motif, AA,Motif, Amino Acid,Motif, Protein,Motifs, AA,Motifs, Protein,Protein Motif,Protein Structures, Supersecondary,Supersecondary Protein Structures