Selective broadening of NMR lines as a criterion in studying the interaction of Mn (II) with amino acids and peptides in D20
Tiezzi, E.; Valensin, D.
Biofizika 21(3): 401-408
1976
ISSN/ISBN: 0006-3029 PMID: 963086 Document Number: 96533
A proton NMR study was carried out on complexes of Mn(II) with amino acids and peptides in aqueous solution. The theory, based on the Solomon-Bloembergen equations, was summarized and discussed. Different types of equilibria involving the anionic and zwittrionic forms of the amino acids were taken into account, together with the presence of outer- and inner-sphere species. The related correlation times were evaluated. Sarcosine, beta-alanine, threonine, tyrosine, valine, beta-alanine, proline, histidine and cystein complexes with Mn(II) were investigated on the basis of the NMR spectra. Moreover, diglycine and triglycine were studied in the presence of manganous ion at different pH value. The findings were discussed in terms of selective broadening of the NMR peaks and compared with data in the literature.