Abstract
The collision-induced dissociation (CID) products b2-b4 from Leu-enkephalin are examined with infrared multiple-photon dissociation (IR-MPD) spectroscopy and gas-phase hydrogen/deuterium exchange (HDX). Infrared spectroscopy reveals that b2 exclusively adopts oxazolone structures, protonated at the N-terminus and at the oxazolone ring N, based on the presence and absence of diagnostic infrared vibrations. This is correlated with the presence of a single HDX rate. For the larger b3 and b4, the IR-MPD measurements display diagnostic bands compatible with a mixture of oxazolone and macrocycle structures. This result is supported by HDX experiments, which show a bimodal distribution in the HDX spectra and two distinct rates in the HDX kinetic fitting. The kinetic fitting of the HDX data is employed to derive the relative abundances of macrocycle and oxazolone structures for b3 and b4, using a procedure recently implemented by our group for a series of oligoglycine b fragments (Chen et al. J. Am. Chem. Soc. 2009, 131(51), 18272–18282. doi: 10.1021/ja9030837). In analogy to that study, the results suggest that the relative abundance of the macrocycle structure increases as a function of b fragment size, going from 0% for b2 to ∼6% for b3, and culminating in 31% for b4. Nonetheless, there are also surprising differences between both studies, both in the exchange kinetics and the propensity in forming macrocycle structures. This indicates that the chemistry of “head-to-tail” cyclization depends on subtle differences in the sequence as well as the size of the b fragment.
Article PDF
Similar content being viewed by others
References
Fenn, J. B.; Mann, M.; Meng, C. K.; Wong, S. F.; Whitehouse, C. M. Electrospray Ionization for Mass Spectrometry of Large Biomolecules. Science 1989, 246, 64–71.
Yamashita, M.; Fenn, J. B. Electrospray Ion Source. Another Variation on the Free-Jet Theme. J. Am. Chem. Soc. 1984, 88, 4451–4459.
Karas, M.; Hillenkamp, F. Laser Desorption Ionization of Proteins with Molecular Masses Exceeding 10,000 Daltons. Anal. Chem. 1988, 60, 2299–2301.
Hillenkamp, F.; Karas, M.; Beavis, R. C.; Chait, B. T. Matrix-Assisted Laser Desorption Ionization Mass-Spectrometry of Biopolymers. Anal. Chem. 1991, 63, A1193-A1202.
Hillenkamp, F.; Karas, M.; Beavis, R. C.; Chait, B. T. Matrix-Assisted Laser Desorption Ionization Mass-Spectrometry of Biopolymers. Anal. Chem. 1991, 63, A1193-A1202.
Roepstorff, P.; Fohlmann, J. Proposal for a Common Nomenclature for Sequence Ions in the Mass Spectra of Peptides. J. Biomed. Mass Spectrom. 1984, 11, 601.
Biemann, K. Contributions of Mass Spectrometry to Peptide and Protein Structure. Biomed. Environ. Mass Spectrom. 1988, 16, 99–111.
Burlet, O.; Yang, C. Y.; Gaskell, S. J. J. Am. Soc. Mass Spectrom. 1992, 3, 337–344.
Dongre, A. R.; Jones, J. L.; Somogyi, A.; Wysocki, V. H. Influence of Peptide Composition, Gas-Phase Basicity, and Chemical Modification on Fragmentation Efficiency: Evidence for the Mobile Proton Model. J. Am. Chem. Soc. 1996, 118, 8365–8374.
Wysocki, V. H.; Tsaprailis, G.; Smith, L. L.; Breci, L. A. Mobile and Localized Protons: A Framework for Understanding Peptide Dissociation. J. Mass Spectrom. 2000, 35, 1399–1406.
Harrison, A. G. To b or Not to b: The Ongoing Saga of Peptide b Ions. Mass Spectrom. Rev. 2009, 28, 640–654.
Yalcin, T.; Khouw, C.; Csizmadia, I. G.; Peterson, M. R.; Harrison, A. G. Why are b Ions Stable Species in Peptide Spectra? J. Am. Soc. Mass Spectrom. 1995, 6, 1165–1174.
Farrugia, J.; O’Hair, R. A. J.; Reid, G. Do All b2 Ions Have Oxazolone Structures? Multistage Mass Spectrometry and Ab Initio Studies on Protonated N-Acyl Amino Acid Methyl Ester Model Systems. Int. J. Mass Spectrom. 2001, 210/211, 71–87.
Farrugia, J.; O’Hair, R. A. J. Involvement of Salt Bridges in a Novel Gas Phase Rearrangement of Protonated Arginine-Containing Dipeptides, which precedes fragmentation. Int. J. Mass Spectrom. 2003, 222, 229–242.
Huang, Y.; Wysocki, V. H.; Tabb, D. L.; Yates, J. R. The Influence of Histidine on Cleavage C-Terminal to Acidic Residues in Doubly Protonated Tryptic Peptides. Int. J. Mass Spectrom. 2002, 219, 233–244.
Kish, M. M.; Wesdemiotis, C. Selective Cleavage at Internal Lysine Residues in Protonated Versus Metalated Peptides. Int. J. Mass Spectrom. 2003, 227, 191–201.
Harrison, A. G.; Young, A. B.; Bleiholder, B.; Suhai, S.; Paizs, B. Scrambling of Sequence Information in Collision-Induced Dissociation of Peptides. J. Am. Chem. Soc. 2006, 128, 10364–10365.
Tang, X.; Thibault, P.; Boyd, R. K. Fragmentation Reactions of Multiply-Protonated Peptides and Implications for Sequencing by Tandem Mass-Spectrometry with Low-Energy Collision-Induced Dissociation. Anal. Chem. 1993, 65, 2824–2834.
Tang, X.; Boyd, R. K. Rearrangement of Doubly-Charged Acylium Ions from Lysyl and Ornithyl Peptides. Rapid Commun. Mass Spectrom. 1994, 8, 678–686.
Vachet, R. W.; Bishop, B. M.; Erickson, B. W.; Glish, G. L. Novel Peptide Dissociation: Gas-Phase Intramolecular Rearrangement of Internal Amino Acid Residues. J. Am. Chem. Soc. 1997, 119, 5481–5488.
Polfer, N. C.; Oomens, J.; Suhai, S.; Paizs, B. Infrared Spectroscopy and Theoretical Studies on Gas-Phase Protonated Leu-Enkephalin and Its Fragments: Direct Evidence for the Mobile Proton. J. Am. Chem. Soc. 2007, 129, 5887–5897.
Yoon, S.; Chamot-Rooke, J.; Perkins, B.; Hilderbrand, A. E.; Poutsma, J.; Wysocki, V. H. IRMPD Spectroscopy Shows that AGG Forms an Oxazolone b Ion. J. Am. Chem. Soc. 2008, 130, 17644–17645.
Oomens, J.; Young, S.; Molesworth, S.; van Stipdonk, M. J. Spectroscopic Evidence for an Oxazolone Structure of the b2 Fragment Ion from Protonated Tri-Alanine. J. Am. Soc. Mass Spectrom. 2009, 20, 334–339.
Perkins, B.; Chamot-Rooke, J.; Yoon, S.; Gucinski, A.; Somogyi, A.; Wysocki, V. H. Evidence of Diketopiperazine and Oxazolone Structures for HA b2+ Ion. J. Am. Chem. Soc. 2009, 131, 17528–17529.
Bythell, B.; Erlekam, U.; Paizs, B.; Maitre, P. Infrared Spectroscopy of Fragments from Doubly Protonated Tryptic Peptides. Chem. Phys. Chem. 2009, 10, 883–885.
Chen, X.; Yu, L.; Steill, J. D.; Oomens, J.; Polfer, N. Effect of Peptide Fragment Size on the Propensity of Cyclization in Collision-Induced Dissociation: Oligoglycine b2–b8. J. Am. Chem. Soc. 2009, 131, 18272–18282.
Herrmann, K. A.; Kuppannan, K.; Wysocki, V. H. Fragmentation of Doubly-Protonated Peptide Ion Populations Labeled by H/D Exchange with CH3OD. Int. J. Mass Spectrom. 2006, 249/250, 93–105.
Somogyi, A. Probing Peptide Fragment Ion Structures by Combining Sustained Off-Resonance Collision-Induced Dissociation and Gas-Phase H/D Exchange (SORI-HDX) in Fourier Transform Ion-Cyclotron Resonance (FT-ICR) Instruments. J. Am. Soc. Mass Spectrom. 2008, 19, 1771–1775.
Fattahia, A.; Zekavata, B.; Soiouki, T. H/D Exchange Kinetics: Experimental Evidence for Formation of Different b Fragment Ion Conformers/Isomers During the Gas-Phase Peptide Sequencing. J. Am. Soc. Mass Spectrom. 2009, 21, 358–369.
Garcia, I.; Giles, K.; Bateman, R. H.; Gaskell, S. J. Studies of Peptide a-and b-Type Fragment Ions Using Stable Isotope Labeling and Integrated Ion Mobility/Tandem Mass Spectrometry. J. Am. Soc. Mass Spectrom. 2008, 19, 1781–1787.
Garcia, I.; Giles, K.; Bateman, R. H.; Gaskell, S. I. Evidence for Structural Variants of a- and b-Type Peptide Fragment Ions Using Combined Ion Mobility/Mass Spectrometry. J. Am. Soc. Mass Spectrom. 2008, 19, 609–613.
Polfer, N. C.; Bohrer, B. C.; Plasencia, M. D.; Paizs, B.; Clemmer, D. E. On the Dynamics of Fragment Isomerization in Collision-Induced Dissociation of Peptides. J. Phys. Chem. A 2008, 112, 1286–1293.
Oepts, D.; van der Meer, A. F. G.; van Amersfoort, P. W. The Free-Electron-Laser User Facility FELIX. Infrared Phys. Technol. 1995, 36, 297–308.
Valle, J. J.; Eyler, J. R.; Oomens, J.; Moore, D. T.; van der Meer, A. F. G.; von Helden, G.; Meijer, G.; Hendrickson, C. L.; Marshall, A. G.; Blakney, G. T. A Free Electron-Fourier Transform Ion Cyclotron Resonance Mass Spectrometry Facility for Obtaining Infrared Multiphoton Dissociation Spectra of Gaseous Ions. Rev. Sci. Instrum. 2005, 76, 23103.
Polfer, N. C.; Oomens, J.; Moore, D. T.; von Helden, G.; Meijer, G.; Dunbar, R. C. Infrared Spectroscopy of Phenylalanine Ag(I) and Zn(II) Complexes in the Gas Phase. J. Am. Chem. Soc. 2006, 128, 517–525.
Dopfer, O. IR Spectroscopy of Microsolvated Aromatic Cluster Ions: Ionization-Induced Switch in Aromatic Molecule-Solvent Recognition. Z Phys. Chem. 2005, 219, 125–168.
Oomens, J.; Sartakov, B.; Meijer, G.; von Helden, G. Gas-Phase Infrared Multiple Photon Dissociation Spectroscopy of Mass-Selected Molecular Ions. Int. J. Mass Spectrom. 2006, 254, 1–19.
Polfer, N. C.; Oomens, J. Reaction Products in Mass Spectrometry Elucidated with Infrared Spectroscopy. Phys. Chem., Chem. Phys. 2007, 9, 3804–3817.
Asmis, K. R.; Sauer, J. Mass-Selective Vibrational Spectroscopy of Vanadium Oxide Cluster Ions. Mass Spectrom. Rev. 2007, 26, 542–562.
MacAleese, L.; Maitre, P. Infrared Spectroscopy of Organometallic Ions in the Gas Phase: From Model to Real World Complexes. Mass Spectrom. Rev. 2007, 26, 583–605.
Eyler, J. R. Infrared Multiple Photon Dissociation Spectroscopy of Ions in Penning Traps. Mass Spectrom. Rev. 2009, 28, 448–467.
Polfer, N. C.; Oomens, J. Vibrational Spectroscopy of Bare and Solvated Ionic Complexes of Biological Relevance. Mass Spectrom. Rev. 2009, 28, 468–494.
Fridgen, T. D. Infrared Consequence Spectroscopy of Protonated and Metal Ion Cationized Complexes. Mass Spectrom. Rev. 2009, 28, 586–607.
Cornell, W. D.; Cieplak, P.; Bayly, C. I.; Gould, I. R.; Merz, K. M.; Ferguson, D. M.; Spellmeyer, D. C.; Fox, T.; Caldwell, J. W.; Kollmann, P. A. A Second Generation Force Field for the Simulation of Proteins, Nucleic Acids, and Organic Molecules. J. Am. Chem. Soc. 1995, 117, 5179–5197.
Frisch, M. J.; Trucks, G. W.; Schlegel, H. B.; Scuseria, G. E.; Robb, M. A.; Cheeseman, J. R.; Montgomery, J. A. Jr.; Vreven, T.; Kudin, K. N.; Burant, J. C.; Millam, J. M.; Iyengar, S. S.; Tomasi, J.; Barone, V.; Mennucci, B.; Cossi, M.; Scalmani, G.; Rega, N.; Petersson, G. A.; Nakatsuji, H.; Hada, M.; Ehara, M.; Toyota, K.; Fukuda, R.; Hasegawa, J.; Ishida, M.; Nakajima, T.; Honda, Y.; Kitao, O.; Nakai, H.; Kiene, M.; Li, X.; Knox, J. E.; Hratchian, H. P.; Cross, J. B.; Bakken, V.; Adamo, C.; Jaramillo, J.; Gomperts, R.; Stratmann, R. E.; Yazyev, O.; Austin, A. J.; Cammi, R.; Pomelli, C.; Ochterski, J. W.; Ayala, P. Y.; Morokurna, K.; Voth, G. A.; Salvador, P.; Dannenberg, J. J.; Zakrzewski, V. G.; Dapprich, S.; Daniels, A. D.; Strain, M. C.; Parkas, O.; Malick, D. K.; Rabuck, A. D.; Raghavachari, K.; Foresman, J. B.; Ortiz, J. V.; Cui, Q.; Baboul, A. G.; Clifford, S.; Cioslowski, J.; Stefanov, B. B.; Liu, G.; Liashenko, A.; Piskorz, P.; Komaromi, I.; Martin, R. L.; Fox, D. J.; Keith, T.; Al-Laham, M. A.; Peng, C. Y.; Nanayakkara, A.; Challacombe, M.; Gill, P. M. W.; Johnson, B.; Chen, W.; Wong, M. W.; Gonzalez, C.: Pople, J. A. Gaussian 03, Revision C 02; Gaussian, Inc.; Wallingford, CT, 2004.
Cieplak, P.; Cornell, W. D.; Bayly, C. I.; Kollmann, P. A. Application for the Multimolecule and Multiconformational RESP Methodology to Biopolymers: Charge Derivation for DNA, RNA, and Proteins. Comput. Chem. 1995, 16, 1357–1377.
Paizs, B.; Suhai, S. Towards Understanding the Tandem Mass Spectra of Protonated Oligopeptides. 1: Mechanism of Amide Bond Cleavage. J. Am. Soc. Mass Spectrom. 2004., 15, 103–113.
Rožman, M.; Kazazic, S.; Klasinc, L.; Sric, D. Kinetics of Gas-Phase Flydrogen/Deuterium Exchange and Gas-Phase Structure of Protonated Phenylalanine, Proline, Tyrosine, and Tryptophan. Rapid Commun. Mass Spectrom. 2003, 17, 2769–2772.
Campbell, S.; Rodgers, M. T.; Marzluff, E. M.; Beauchamp, J. L. Deuterium Exchange Reactions as Probe of Biomolecule Structure. Fundamental Studies of Gas Phase Reactions of Protonated Glycine Oligomers with D2O, CD3OD, CD3CO2D, and ND3. J. Am. Chem. Soc. 1995, 117, 12840–12854.
Wyttenbach, T.; Bowers, M. T. Gas Phase Conformations of Biological Molecules: The Hydrogen/Deuterium Exchange Mechanism. J. Am. Soc. Mass Spectrom. 1999, 10, 9–14.
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Chen, X., Steill, J.D., Oomens, J. et al. Oxazolone versus macrocycle structures for leu-enkephalin b2–b4: Insights from infrared multiple-photon dissociation spectroscopy and gas-phase hydrogen/deuterium exchange. J Am Soc Mass Spectrom 21, 1313–1321 (2010). https://doi.org/10.1016/j.jasms.2010.02.022
Received:
Revised:
Accepted:
Issue Date:
DOI: https://doi.org/10.1016/j.jasms.2010.02.022