title: Binding position analysis of target proteins with the use of amidopyrene probes as LA-LDI enhancing tags.
abstract: Amidopyrene-conjugated compounds can be detected by label-assisted laser desorption/ionization mass spectrometry (LA-LDI MS) without matrixes. When actin, a cytoskeletal protein, was labeled with an excess amount of amidopyrene N-hydroxysuccinate (apy-OSu), eight apy-labeled actin peptides were predominantly detected by LA-LDI MS. Then actin was labeled with an amidopyrene NHS ester of the antitumor marine macrolide aplyronine A (ApA-apy-OSu) to form a 1 : 1 conjugate. The sequence of an apy-labeled peptide was established as A(108)PLNPKANR(116) by MS/MS analysis, in which the NHS ester moiety specifically reacted with the ε-amino group of K113. While the fragmentation at the linker part reduces the detection sensitivity of apy-labeled peptides on LA-LDI MS, our chemical probe method is useful for analyzing the binding modes of various ligands and target biomacromolecules that include multiple and weak interactions.
authors.affiliation: Graduate School of Pure and Applied Sciences, University of Tsukuba, Japan. mkita@chem.tsukuba.ac.jp kigoshi@chem.tsukuba.ac.jp.
authors.forename: Kozo
authors.initials: K
authors.lastname: Yoneda
authors.forename: Yaping
authors.initials: Y
authors.lastname: Hu
authors.forename: Rei
authors.initials: R
authors.lastname: Watanabe
authors.forename: Masaki
authors.initials: M
authors.lastname: Kita
authors.forename: Hideo
authors.initials: H
authors.lastname: Kigoshi
mesh_terms: D000199:Actins / Q000737:chemistry*; D001665:Binding Sites; D008958:Models, Molecular; D015335:Molecular Probes / Q000737:chemistry*; D015394:Molecular Structure; D011721:Pyrenes / Q000737:chemistry*; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
chemical_list: D000199:Actins; D015335:Molecular Probes; D011721:Pyrenes