1.2 A refinement of the Kunitz-type domain from the alpha3 chain of human type VI collagen.
The recombinant Kunitz-type domain (C5) of human collagen alpha3(VI) chain was previously described at 1.6 A resolution at room temperature. By changing the crystallization conditions and using synchrotron radiation, we are able to record diffraction data to 1.2 A resolution for crystals of the same space group at 291 K. The protein-water-ion model has been refined anisotropically against these new data using the program SHELXL93; the results converged to an R factor of 15.0%, with all data between 7 and 1.2 A. The final electron-density map reveals a clear chain tracing with a few disordered residues and five residues out of 58 that present alternate conformations. The Cys14-Cys38 bond presents the less frequently observed left-hand conformation (chi1 = -60 degrees). The solvent molecules and a phosphate ion are well ordered with an average B of 38 A2. The high-resolution structure reveals the N and C termini which were missing from the 1.6 A structure.
Laboratoire d'Enzymologie et Biochimie Structurales, CNRS, 91198 Gif sur Yvette CEDEX, France.
K
K
Merigeau
B
B
Arnoux
D
D
Perahia
K
K
Norris
F
F
Norris
A
A
Ducruix
D000595:Amino Acid Sequence; D003094:Collagen / Q000737:chemistry*; D018360:Crystallography, X-Ray; D006801:Humans; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010446:Peptide Fragments / Q000737:chemistry*; D017434:Protein Structure, Tertiary; D011994:Recombinant Proteins / Q000737:chemistry
D010446:Peptide Fragments; D011994:Recombinant Proteins; D003094:Collagen