1dey | pdb_00001dey
NMR SOLUTION STRUCTURE OF CO(II)-BLEOMYCIN A2
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Overview
Previous studies on the coordination chemistry of Co-bleomycin have, suggested the secondary amine in beta-aminoalanine, the N5 and N1, nitrogens in the pyrimidine and imidazole rings, respectively, and the, amide nitrogen in beta-hydroxyhistidine as equatorial ligands to the, cobalt ion. The primary amine in beta-aminoalanine and the carbamoyl group, of the mannose have been proposed alternatively as possible axial ligands., The first coordination sphere of Co(II) in Co(II)BLM has been investigated, in the present study through the use of NMR and molecular dynamics, calculations. The data collected from the NMR experiments are in agreement, with the equatorial ligands previously proposed, and also support the, participation of the primary amine as an axial ligand. The paramagnetic, shifts of the gulose and mannose protons could suggest the latter as a, second axial ligand. This possibility was investigated by way of molecular, dynamics, with distance restraints derived from the relaxation times, measured through NMR. The molecular dynamics results indicate that the, most favorable structure is six-coordinate, with the primary amine and, either the carbamoyl oxygen or a solvent molecule occupying the axial, sites. The analysis of the structures previously derived for, HOO-Co(III)-bleomycin and HOO-Co(III)-pepleomycin led us to propose the, six-coordinate structure with only endogenous ligands, as the one held in, solution by the Co(II) derivative of bleomycin.
About this Structure
1DEY is a Protein complex structure of sequences from [1] with CO and BLM as ligands. Full crystallographic information is available from OCA.
Reference
Coordination chemistry of co(II)-bleomycin: its investigation through NMR and molecular dynamics., Lehmann TE, Serrano ML, Que L Jr, Biochemistry. 2000 Apr 11;39(14):3886-98. PMID:10747776
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