title: Nonstatistical UV Fragmentation of Gas-Phase Peptides Reveals Conformers and Their Structural Features.
abstract: Solving the 3D structure of a biomolecule requires recognition of its conformers and measurements of their individual structural identities, which can be compared with calculations. We employ the phenomenon of nonstatistical photofragmentation, detected by a combination of UV cold ion spectroscopy and high-resolution mass spectrometry, to identify the main conformers of gas-phase peptides and to recover individual UV absorption and mass spectra of all of these conformers in a single laser scan. We first validate this approach with a benchmark dipeptide, Tyr-Ala, and then apply it to a decapeptide, gramicidin S. The revealed characteristic structural difference between the conformers of the latter identifies some of the previously calculated structures of gramicidin S as the most likely geometries of its remaining unsolved conformer.
authors.affiliation: Laboratoire de Chimie Physique Moléculaire, École Polytechnique Fédérale de Lausanne , Station-6, 1015 Lausanne, Switzerland.
authors.forename: Vladimir
authors.initials: V
authors.lastname: Kopysov
authors.affiliation: Thermo Fisher Scientific , Hanna-Kunath Str. 11, 28199 Bremen, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Makarov
authors.affiliation: Laboratoire de Chimie Physique Moléculaire, École Polytechnique Fédérale de Lausanne , Station-6, 1015 Lausanne, Switzerland.
authors.forename: Oleg V
authors.initials: OV
authors.lastname: Boyarkin
mesh_terms: D004151:Dipeptides / Q000737:chemistry / Q000528:radiation effects*; D006096:Gramicidin / Q000737:chemistry / Q000528:radiation effects*; D013058:Mass Spectrometry; D017434:Protein Structure, Tertiary; D014466:Ultraviolet Rays
chemical_list: D004151:Dipeptides; D006096:Gramicidin