title: Fragmentation behavior of a thiourea-based reagent for protein structure analysis by collision-induced dissociative chemical cross-linking.
abstract: The fragmentation behavior of a novel thiourea-based cross-linker molecule specifically designed for collision-induced dissociation (CID) MS/MS experiments is described. The development of this cross-linker is part of our ongoing efforts to synthesize novel reagents, which create either characteristic fragment ions or indicative constant neutral losses (CNLs) during tandem mass spectrometry allowing a selective and sensitive analysis of cross-linked products. The new derivatizing reagent for chemical cross-linking solely contains a thiourea moiety that is flanked by two amine-reactive N-hydroxy succinimide (NHS) ester moieties for reaction with lysines or free N-termini in proteins. The new reagent offers simple synthetic access and easy structural variation of either length or functionalities at both ends. The thiourea moiety exhibits specifically tailored CID fragmentation capabilities--a characteristic CNL of 85 u--ensuring a reliable detection of derivatized peptides by both electrospray ionization (ESI) and matrix-assisted laser desorption/ionization (MALDI) tandem mass spectrometry and as such possesses a versatile applicability for chemical cross-linking studies. A detailed examination of the CID behavior of the presented thiourea-based reagent reveals that slight structural variations of the reagent will be necessary to ensure its comprehensive and efficient application for chemical cross-linking of proteins.
authors.affiliation: Department of Pharmaceutical Chemistry and Bioanalytics, Institute of Pharmacy, Martin-Luther-Universität Halle-Wittenberg, Wolfgang-Langenbeck-Str. 4, D-06120 Halle (Saale), Germany.
authors.forename: Mathias Q
authors.initials: MQ
authors.lastname: Müller
authors.forename: Frank
authors.initials: F
authors.lastname: Dreiocker
authors.forename: Christian H
authors.initials: CH
authors.lastname: Ihling
authors.forename: Mathias
authors.initials: M
authors.lastname: Schäfer
authors.forename: Andrea
authors.initials: A
authors.lastname: Sinz
mesh_terms: D000818:Animals; D002645:Chickens; D003432:Cross-Linking Reagents / Q000737:chemistry*; D007987:Gonadotropin-Releasing Hormone / Q000737:chemistry; D009113:Muramidase / Q000737:chemistry; D010446:Peptide Fragments / Q000737:chemistry*; D011487:Protein Conformation; D011506:Proteins / Q000737:chemistry*; D013373:Substance P / Q000737:chemistry; D013388:Succinimides / Q000737:chemistry; D053719:Tandem Mass Spectrometry / Q000379:methods*; D013890:Thiourea / Q000737:chemistry*
chemical_list: D003432:Cross-Linking Reagents; D010446:Peptide Fragments; D011506:Proteins; D013388:Succinimides; C032620:succinimide; D013373:Substance P; D007987:Gonadotropin-Releasing Hormone; D009113:Muramidase; D013890:Thiourea