@article {2664,
	title = {Gas-Phase H/D Exchange and Collision Cross Sections of Hemoglobin Monomers, Dimers, and Tetramers},
	journal = {Journal of the American Society for Mass Spectrometry},
	volume = {20},
	number = {3},
	year = {2009},
	note = {ISI Document Delivery No.: 417NGTimes Cited: 1Cited Reference Count: 71Wright, P. John Douglas, D. J.},
	month = {Mar},
	pages = {484-495},
	type = {Article},
	abstract = {The conformations of gas-phase ions of hemoglobin, and its dimer and monomer subunits have been studied with H/D exchange and cross section measurements. During the H/D exchange measurements, tetramers undergo slow dissociation to dimers, and dimers to monomers, but this did not prevent drawing conclusions about the relative exchange levels of monomers, dimers, and tetramers. Assembly of the monomers into tetramers, hexamers, and octamers causes the monomers to exchange a greater fraction of their hydrogens. Dimer ions, however, exchange a lower fraction of their hydrogens than monomers or tetramers. Solvation of tetramers affects the exchange kinetics. Solvation molecules do not appear to exchange, and solvation lowers the overall exchange level of the tetramers. Cross section measurements show that monomer ions in low charge states, and tetramer ions have compact structures, comparable in size to the native conformations in solution. Dimers have remarkably compact structures, considerably smaller than the native conformation in solution and smaller than might be expected from the monomer or tetramer cross sections. This is consistent with the relatively low level of exchange of the dimers. (J Am Soc Mass Spectrom 2009, 20, 484-495) (C) 2009 Published by Elsevier Inc. on behalf of American Society for Mass Spectrometry},
	keywords = {ACID-INDUCED DENATURATION, CYTOCHROME-C IONS, DIFFERENT SOLUTION CONFORMATIONS, ELECTROSPRAY MASS-SPECTROMETRY, EXCHANGE, GLOBIN CHAINS, HYDROGEN/DEUTERIUM, ION-TRAP, MYOGLOBIN IONS, noncovalent protein complexes, OF-FLIGHT SYSTEM, QUADRUPOLE},
	isbn = {1044-0305},
	url = {<Go to ISI>://000264082200018},
	author = {Wright, P. J. and Douglas, D. J.}
}
@article {449,
	title = {Collision cross sections of gas phase DNA ions},
	journal = {International Journal of Mass Spectrometry},
	volume = {219},
	number = {1},
	year = {2002},
	note = {ISI Document Delivery No.: 591BVTimes Cited: 4Cited Reference Count: 27},
	month = {Aug},
	pages = {161-170},
	type = {Article},
	abstract = {Collision cross sections of negative ions of a 28-, 40- and 55-mer of single stranded DNA have been measured by an energy loss method, and compared to collision cross sections of proteins of nearly the same molecular weight-ubiquitin, cytochrome c and apomyoglobin, respectively. The oligonucleotides produce negative charge states in electrospray ionization (ESI) similar to the positive charge states produced by the proteins denatured in solution. Cross sections for deoxynucleotide ions increase with charge state in a manner similar to those of protein ions. However, for a given molecular weight and charge state, the cross sections of the oligodeoxynucleotide ions are about 22\% lower than those of the proteins. (C) 2002 Elsevier Science B.V. All rights reserved.},
	keywords = {collision cross sections, CONFORMATION, CONFORMERS, DNA ions, ELECTROSPRAY MASS-SPECTROMETRY, gas phase, MYOGLOBIN, PROTEIN IONS, SEQUENCE, VACUUM},
	isbn = {1387-3806},
	url = {<Go to ISI>://000177860600015},
	author = {Moradian, A. and Scalf, M. and Westphall, M. S. and Smith, L. M. and Douglas, D. J.}
}
@article {4006,
	title = {Dissociation of heme from myoglobin and cytochrome b(5): Comparison of behavior in solution and the gas phase},
	journal = {Biochemistry},
	volume = {36},
	number = {5},
	year = {1997},
	note = {ISI Document Delivery No.: WG072Times Cited: 79Cited Reference Count: 6144th ASMS Conference on Mass Spectrometry and Allied TopicsMAY 12-16, 1996PORTLAND, ORASMS},
	month = {Feb},
	pages = {1018-1025},
	type = {Proceedings Paper},
	abstract = {The relationship of the structure of a protein in solution to the structure of a gas-phase protein ion and the manner in which gas-phase protein ions bind small molecules noncovalently are topics of current debate. To address these issues, the stability of heme binding to wild-type and variant forms of apomyoglobin and apocytochrome bs has been studied in the gas phase by electrospray mass spectrometry (ES-MS) and compared with the stability of heme binding to the same proteins in solution. The voltage required to dissociate ions of the heme-protein complexes in the orifice-skimmer region of an electrospray mass spectrometer, a measure of the complex stability, is found to be correlated with the activation energy for dissociation of the complexes in solution across a series of proteins in which the number of hydrogen bonds between the heme propionate groups and surface residues is systematically reduced. However, variants in which the hydrogen bonds to the proximal histidine have been removed are destabilized in solution but stabilized in the gas-phase ions. These results suggest that on the millisecond time scale of the ES-MS experiment, the gas-phase protein ion may retain much of the structure of the protein in solution, at least for those residues surrounding the heme group. Furthermore, the ability of ES-MS to detect relatively subtle differences in protein-small molecule complex stability demonstrated in this work suggests that this technique may be a convenient, sensitive, and generally useful strategy for physical characterization of such complexes.},
	keywords = {ATMOSPHERIC-PRESSURE, CONFORMATION, ELECTROSPRAY MASS-SPECTROMETRY, FEATURES, IONIZATION, LARGE MOLECULES, NONCOVALENT INTERACTIONS, PROTEIN IONS, REORIENTATION, STABILITY},
	isbn = {0006-2960},
	url = {<Go to ISI>://A1997WG07200006},
	author = {Hunter, C. L. and Mauk, A. G. and Douglas, D. J.}
}
@article {3635,
	title = {Conformation of gas-phase myoglobin ions},
	journal = {Journal of the American Chemical Society},
	volume = {118},
	number = {18},
	year = {1996},
	note = {ISI Document Delivery No.: UK145Times Cited: 89Cited Reference Count: 33},
	month = {May},
	pages = {4488-4489},
	type = {Article},
	keywords = {CYTOCHROME-C, ELECTROSPRAY MASS-SPECTROMETRY, IONIZATION, PROTEINS},
	isbn = {0002-7863},
	url = {<Go to ISI>://A1996UK14500034},
	author = {Collings, B. A. and Douglas, D. J.}
}
