D. Brewer et G. Lajoie, Evaluation of the metal binding properties of the histidine-rich antimicrobial peptides histatin 3 and 5 by electrospray ionization mass spectrometry, RAP C MASS, 14(19), 2000, pp. 1736-1745
Electrospray ionization mass spectrometry (ESI-MS) was used to investigate
metal ion interactions with salivary peptides histatin 3 (H3) and histatin
5 (H5), Conformational changes of these peptides in the presence of metal i
ons were studied using circular dichroism spectroscopy. H3 and H5 formed hi
gh affinity complexes with Cu2+ and Ni2+ and, to a lesser extent, with Zn2. Both peptides show the potential for multiple binding sites for Cu2+ and
Ni2+ and only a single strong binding site for Zn2+. The binding of a third
Cu2+ ion to H3 seems to enable the binding of a fourth ion to H3. The bind
ing of a second and third Ni2+ ion to H5 has a similar effect in enabling t
he binding of a fourth ion. None of the metal ions examined stabilized a re
gular secondary structure for either peptide, Subtle changes in overall con
formation are seen with the addition of Cu2+ to both H3 and H5. Copyright (
C) 2000 John Wiley & Sons, Ltd.