Supermetallization is the recently observed phenomenon of the formation of complex ions of peptide–metal in the gas phase when the peptide accepts an unexpectedly large number of metal atoms. It has been found that supermetallization takes place during electrospray ionization when charged droplets are evaporating at relatively high temperature (ca 400 °C). In the present paper, we demonstrate supermetallized complexes of small protein ubiquitin and two peptides with Th(IV). We have observed complexes of ubiquitin with up to five thorium atoms, and attaching each Th(IV) requires the removal of four hydrogen atoms. To our knowledge, this is the first demonstration of gas-phase complexes of peptides and proteins with tetravalent metal atoms.
ZawiszaI.RózgaM.BalW., “Affinity of copper and zinc ions to proteins and peptides related to neurodegenerative conditions (Aβ, APP, α-synuclein, PrP)”, Coord. Chem. Rev.256, 2297 (2012). doi: http://dx.doi.org/10.1016/j.ccr.2012.03.012
2.
TaraszkaJ.A.LiJ.W.ClemmerD.E., “Metal-mediated peptide ion conformations in the gas phase”J. Phys. Chem. B, 104, 4545 (2000). doi: http://dx.doi.org/10.1021/jp9939468
3.
SigelH.MartinR.B., “The colorless 'chameleon or the peculiar properties of Zn2+ in complexes in solution. Quantification of equilibria involving a change of the coordination number of the metal ion”, Chem. Soc. Rev.23, 83 (1994). doi: http://dx.doi.org/10.1039/CS9942300083
4.
GrewalR.N.El AribiH.SmithJ.C.RodriquezC.F.HopkinsonA.C.SiuK.W.M., “Multiple substitution of protons by sodium ions in sodiated oligoglycines”Int. J. Mass Spectrom.219, 89 (2002). doi: http://dx.doi.org/10.1016/S1387-3806(02)00561-4
5.
KostyukevichY.KononikhinA.PopovI.NikolaevE., “Conformations of cationized linear oligosaccharides revealed by FTMS combined with in-ESI H/D exchange”J. Mass Spectrom.50, 1150 (2015). doi: http://dx.doi.org/10.1002/jms.3633
6.
LavanantH.HecquetE.HoppilliardY., “Complexes of l-histidine with Fe2+, Co2+, Ni2+, Cu2+, Zn2+ studied by electrospray ionization mass spectrometry”, Int. J. Mass Spectrom.185, 11 (1999). doi: http://dx.doi.org/10.1016/S1387-3806(98)14044-7
7.
CrizerD.M.XiaY.McLuckeyS.A., “Transition metal complex cations as reagents for gas-phase transformation of multiply deprotonated polypeptides”, J. Am. Soc. Mass Spectrom.20, 1718 (2009). doi: http://dx.doi.org/10.1016/j.jasms.2009.05.008
FlickT.G.DonaldW.A.WilliamsE.R., “Electron capture dissociation of trivalent metal ion-peptide complexes”, J. Am. Soc. Mass Spectrom.24, 193 (2013). doi: http://dx.doi.org/10.1007/s13361-012-0507-7
10.
FlickT.G.MerenbloomS.I.WilliamsE.R., “Effects of metal ion adduction on the gas-phase conformations of protein ions”, J. Am. Soc. Mass Spectrom.24, 1654 (2013). doi: http://dx.doi.org/10.1007/s13361-013-0664-3
11.
FlickT.G.WilliamsE.R., “Supercharging with trivalent metal ions in native mass spectrometry”, J. Am. Soc. Mass Spectrom.23, 1885 (2012). doi: http://dx.doi.org/10.1007/s13361-012-0463-2
12.
GongY.HuH.-S.TianG.RaoL.LiJ.GibsonJ.K., “A tetrapositive metal ion in the gas phase: Thorium(IV) coordinated by neutral tridentate ligands”, Angew. Chem. Int. Ed.52, 6885 (2013). doi: http://dx.doi.org/10.1002/anie.201302212
13.
KostyukevichY.KononikhinA.PopovI.IndeykinaM.KozinS.A.MakarovA.A.NikolaevE., “Supermetallization of peptides and proteins during electrospray ionization”, J. Mass Spectrom.50, 1079 (2015). doi: http://dx.doi.org/10.1002/jms.3622
14.
KostyukevichY.KononikhinA.PopovI.NikolaevE., “Conformational changes of ubiquitin during electrospray ionization as determined by in-ESI source H/D exchange combined with high-resolution MS and ECD fragmentation”, J. Mass Spectrom.49, 989 (2014). doi: http://dx.doi.org/10.1002/jms.3409
15.
KostyukevichY.KononikhinA.PopovI.SpasskiyA.NikolaevE., “In ESI-source H/D exchange under atmospheric pressure for peptides and proteins of different molecular weights from 1 to 66 kDa: The role of the temperature of the desolvating capillary on H/D exchange. J. Mass Spectrom.50, 49 (2015). doi: http://dx.doi.org/10.1002/jms.3535
