1VDF

ASSEMBLY DOMAIN OF CARTILAGE OLIGOMERIC MATRIX PROTEIN

Summary for 1VDF

• Entry DOI: 10.2210/pdb1vdf/pdb
• Descriptor: CARTILAGE OLIGOMERIC MATRIX PROTEIN, CHLORIDE ION (3 entities in total)
• Functional Keywords: extracellular matrix protein, assembly domain, cartilage, oligomeric matrix protein, glycoprotein
• Biological source: Rattus norvegicus (Norway rat)
• Cellular location: Secreted, extracellular space, extracellular matrix (By similarity): P35444
• Total number of polymer chains: 5
• Total formula weight: 26531.10

Authors

Malashkevich, V.N. (deposition date: 1996-09-12, release date: 1997-10-08, Last modification date: 2024-10-23)

Primary citation

Malashkevich, V.N.,Kammerer, R.A.,Efimov, V.P.,Schulthess, T.,Engel, J.
The crystal structure of a five-stranded coiled coil in COMP: a prototype ion channel?
Science, 274:761-765, 1996

PubMed Abstract: Oligomerization by the formation of alpha-helical bundles is common in many proteins. The crystal structure of a parallel pentameric coiled coil, constituting the oligomerization domain in the cartilage oligomeric matrix protein (COMP), was determined at 2.05 angstroms resolution. The same structure probably occurs in two other extracellular matrix proteins, thrombospondins 3 and 4. Complementary hydrophobic interactions and conserved disulfide bridges between the alpha helices result in a thermostable structure with unusual properties. The long hydrophobic axial pore is filled with water molecules but can also accommodate small apolar groups. An "ion trap" is formed inside the pore by a ring of conserved glutamines, which binds chloride and probably other monatomic anions. The oligomerization domain of COMP has marked similarities with proposed models of the pentameric transmembrane ion channels in phospholamban and the acetylcholine receptor.

PubMed: 8864111
DOI: 10.1126/science.274.5288.761

Experimental method

X-RAY DIFFRACTION (2.05 Å)