Open AccessCollision-activated dissociation, infrared multiphoton dissociation, and electron capture dissociation of the Bacillus anthracis siderophore petrobactin and its metal ion complexes
Author(s) -
Haichuan Liu,
Kristina Håkansson,
Jung Yeop Lee,
David H. Sherman
Publication year - 2007
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/j.jasms.2007.01.005
Subject(s) - infrared multiphoton dissociation , chemistry , dissociation (chemistry) , electron capture dissociation , protonation , siderophore , metal , fragmentation (computing) , photochemistry , metal ions in aqueous solution , ion , tandem mass spectrometry , crystallography , mass spectrometry , biochemistry , organic chemistry , chromatography , computer science , gene , operating system
Siderophores are high-affinity iron-chelating ligands produced by microorganisms to scavenge vital Fe(3+) from the environment. Thus, siderophores constitute potential therapeutic targets and their structural determination is important for exploiting their therapeutic value. Here, the virulence-associated siderophore petrobactin from Bacillus anthracis was characterized with electron capture dissociation (ECD). Fragmentation of doubly protonated petrobactin was investigated and compared to sustained off-resonance irradiation collision-activated dissociation (SORI CAD) and infrared multiphoton dissociation (IRMPD) of both the singly and doubly protonated species. These experiments demonstrate that ECD provides additional information (complementary bond cleavages) on the structure of petrobactin compared to both SORI CAD and IRMPD. Furthermore, complexes of petrobactin with divalent (Ca(2+), Fe(2+), and Co(2+)) and trivalent (Fe(3+) and Ga(3+)) metal cations were also subjected to SORI CAD and ECD. Again, most structural information was obtained from the ECD spectra. However, significant differences were found in both SORI CAD and ECD of metal complexes, dependent on the nature of the metal ion. Intriguingly, unique behavior, consistent with a recently proposed solution-phase structure, was observed for the highly preferred Fe(3+)-petrobactin complex.