Open AccessComplexes of iron(II) with cysteine-containing peptides in the gas phase
Author(s) -
Olga V. Nemirovskiy,
Michael L. Gross
Publication year - 1996
Publication title -
journal of the american society for mass spectrometry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.961
H-Index - 127
eISSN - 1879-1123
pISSN - 1044-0305
DOI - 10.1016/1044-0305(96)00054-2
Subject(s) - chemistry , cysteine , pentapeptide repeat , thiol , sulfur , fragmentation (computing) , tandem mass spectrometry , fast atom bombardment , mass spectrometry , ion , molecule , metal , peptide , metal ions in aqueous solution , inorganic chemistry , stereochemistry , organic chemistry , chromatography , biochemistry , enzyme , computer science , operating system
Gas-phase interactions of peptides that contain cysteine with iron(II) atoms were examined by using fast-atom bombardment and tandem mass spectrometry. Specific and strong interactions of iron and sulfur from the thiol group of the cysteine side chain occur in the gas phase and are the basis for highly specific fragmentation to give abundant [a n -(+) ions. For peptides that contain two cysteines, an internal ion, which results from the interaction of Fe and both thiol groups, is formed upon collisional activation. The mechanism for the formation of [a n -2H+Fe](+) fragment ions requires the metal to be coordinated at sulfur in close proximity to the site of reaction. Iron-bis(pentapeptide) complexes, which form under the same conditions, decompose predominantly to lose a pentapeptide molecule and, to a lesser extent, to give [a a -2H+Fe](+) ions.