title: Mapping protein surface accessibility via an electron transfer dissociation selectively cleavable hydrazone probe.
abstract: A protein's surface influences its role in protein-protein interactions and protein-ligand binding. Mass spectrometry can be used to give low resolution structural information about protein surfaces and conformations when used in combination with derivatization methods that target surface accessible amino acid residues. However, pinpointing the resulting modified peptides upon enzymatic digestion of the surface-modified protein is challenging because of the complexity of the peptide mixture and low abundance of modified peptides. Here a novel hydrazone reagent (NN) is presented that allows facile identification of all modified surface residues through a preferential cleavage upon activation by electron transfer dissociation coupled with a collision activation scan to pinpoint the modified residue in the peptide sequence. Using this approach, the correlation between percent reactivity and surface accessibility is demonstrated for two biologically active proteins, wheat eIF4E and PARP-1 Domain C.
authors.affiliation: Department of Chemistry and Biochemistry, The University of Texas at Austin, 1 University Station A5300, Austin, TX 78712, USA.
authors.forename: Lisa
authors.initials: L
authors.lastname: Vasicek
authors.forename: John P
authors.initials: JP
authors.lastname: O'Brien
authors.forename: Karen S
authors.initials: KS
authors.lastname: Browning
authors.forename: Zhihua
authors.initials: Z
authors.lastname: Tao
authors.forename: Hung-Wen
authors.initials: HW
authors.lastname: Liu
authors.forename: Jennifer S
authors.initials: JS
authors.lastname: Brodbelt
mesh_terms: D004579:Electron Transport; D039561:Eukaryotic Initiation Factor-4E / Q000032:analysis* / Q000737:chemistry; D006801:Humans; D006835:Hydrazones / Q000737:chemistry*; D015335:Molecular Probes; D010940:Plant Proteins / Q000032:analysis*; D011065:Poly(ADP-ribose) Polymerases / Q000032:analysis* / Q000737:chemistry; D017434:Protein Structure, Tertiary; D040901:Proteomics; D013499:Surface Properties; D053719:Tandem Mass Spectrometry; D014908:Triticum / Q000737:chemistry
chemical_list: D039561:Eukaryotic Initiation Factor-4E; D006835:Hydrazones; D015335:Molecular Probes; D010940:Plant Proteins; D011065:Poly(ADP-ribose) Polymerases