Structure of copper- and oxalate-substituted human lactoferrin at 2.0 A resolution.Smith, C.A., Anderson, B.F., Baker, H.M., Baker, E.N.
(1994) Acta Crystallogr.,Sect.D 50: 302-316
- PubMed: 15299444
- DOI: 10.1107/S0907444994000491
- PubMed Abstract:
- Anion Binding by Human Lactoferrin: Results from Crystallographic and Physicochemical Studies
Shongwe, M.S.,Smith, C.A.,Ainscough, E.W.,Baker, H.M.,Brodie, A.M.,Baker, E.N.
(1992) Biochemistry 31: 4451
- Preliminary Crystallographic Studies of Copper(II)-and Oxalate-Substituted Human Lactoferrin
Smith, C.A.,Baker, H.M.,Baker, E.N.
(1991) J.Mol.Biol. 219: 155
- Structure of Human Lactoferrin: Crystallographic Structure Analysis and Refinement at 2.8 Angstroms Resolution
Anderson, B.F.,Baker, H.M.,Norris, G.E.,Rice, D.W.,Baker, E.N.
(1989) J.Mol.Biol. 209: 711
The three-dimensional structure of human dicupric monooxalate lactoferrin, Cu(2)oxLf, has been determined to 2.0 A resolution, using X-ray diffraction data collected by diffractometry to 2.5 A resolution, and oscillation photography on a synchrotron ...
The three-dimensional structure of human dicupric monooxalate lactoferrin, Cu(2)oxLf, has been determined to 2.0 A resolution, using X-ray diffraction data collected by diffractometry to 2.5 A resolution, and oscillation photography on a synchrotron source to 2.0 A resolution. Difference electron-density maps calculated between Cu(2)oxLf and both dicupric lactoferrin, Cu(2)Lf, and diferric lactoferrin, Fe(2)Lf, showed that the oxalate had replaced a carbonate in the C-terminal binding site, and that, relative to Cu(2)Lf, there were no significant differences in the N-terminal site. The structure was then refined crystallographically by restrained least-squares methods. The final model, in which the r.m.s. deviation in bond distances is 0.017 A, contains 5314 protein atoms (691 residues), two Cu(2+) ions, one bicarbonate ion, one oxalate ion, 325 solvent molecules and one sugar residue. The crystallographic R factor of 0.193 is for 46 134 reflections in the range 8.0 to 2.0 A resolution. The oxalate ion is coordinated to copper in a 1,2-bidentate fashion, and the added bulk of the anion results in the rearrangement of the side chains of nearby arginine and tyrosine residues. No other major alterations in the molecule can be observed, the overall protein structure being the same as that for Cu(2)Lf and Fe(2)Lf.
Department of Chemistry and Biochemistry, Massey University, Palmerston North, New Zealand.