ISSN:
0006-3525
Keywords:
rubredoxin
;
iron(II)/cysteine peptide complex
;
aqueous micelle solution
;
NH - S hydrogen bond
;
aromatic ring
;
19F-nmr
;
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
The absorption, CD, and 1H- and 19F-nmr spectroscopic features of Fe(II) complexes with a series of cysteine-containing oligopeptides were investigated in aqueous (H2O or D2O) 10% Triton X-100 micelle solution. The complexes with distal aromatic rings, [Fe(Z-cys-Pro-Leu-cys-Gly-X)2]2- (Z = benzyloxycarbonyl; X = NH-C6H4-p-F, NH-CH2-CH2-C6H4-p-F, and Phe-OMe), were found to be quite stable in such aqueous micelle solution. The coordination of cysteine-peptide ligands to the Fe(II) ion is revealed by isotropically shifted 1H-nmr signals due to the Cys CβH2 protons occurring at 120 ∼ 250 ppm in a D2O Triton X-100 micelle solution (10%) at 60°C that are very similar to those reported for native reduced rubredoxin. The high stability of these cysteine peptide-Fe(II) complexes in aqueous micellar system was explained by the combined contributions from NH - S hydrogen bonds and the effect of the proximity of aromatic groups. The existence of such NH - S hydrogen bonds and interactions between aromatic ring and sulfur atom was confirmed by 19F-nmr spectral and 19F spin-lattice relaxation times (T1) measurements. © 1998 John Wiley & Sons, Inc. Biopoly 46: 1-10, 1998
Additional Material:
4 Ill.
Type of Medium:
Electronic Resource
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