000266997 001__ 266997
000266997 005__ 20190710181254.0
000266997 022__ $$a0003-2700
000266997 022__ $$a1520-6882
000266997 02470 $$a000469304300043$$2isi
000266997 0247_ $$a10.1021/acs.analchem.9b00770$$2doi
000266997 037__ $$aARTICLE
000266997 245__ $$aMethod for Identification of Threonine Isoforms in Peptides by Ultraviolet Photofragmentation of Cold Ions
000266997 260__ $$c2019$$aWashington$$bAMER CHEMICAL SOC
000266997 269__ $$a2019-05-21
000266997 336__ $$aJournal Articles
000266997 520__ $$aIdentification of isomeric amino acid residues in peptides and proteins is challenging but often highly desired in proteomics. One of the practically important cases that require isomeric assignments is that associated with single-nucleotide polymorphism substitutions of Met residues by Thr in cancer-related proteins. These genetically encoded substitutions can yet be confused with the chemical modifications, arising from protein alkylation by iodoacetamide, which is commonly used in the standard procedure of sample preparation for proteomic analysis. Similar to the genetically encoded mutations, the alkylation also induces a conversion of methionine residues, but to the iso-threonine form. Recognition of the mutations therefore requires isoform-sensitive detection techniques. Herein, we demonstrate an analytical method for reliable identification of isoforms of threonine residues in tryptic peptides. It is based on ultraviolet photodissociation mass spectrometry of cryogenically cooled ions and a machine-learning algorithm. The measured photodissociation mass spectra exhibit isoform-specific patterns, which are independent of the residues adjacent to threonine or iso-threonine in a peptide sequence. A comprehensive metric-based evaluation demonstrates that, being calibrated with a set of model peptides, the method allows for isomeric identification of threonine residues in peptides of arbitrary sequence.
000266997 650__ $$aChemistry, Analytical
000266997 650__ $$aChemistry
000266997 6531_ $$ashotgun-proteomics
000266997 6531_ $$a193 nm
000266997 6531_ $$amass-spectrometry
000266997 6531_ $$aacid-residues
000266997 6531_ $$afragmentation
000266997 6531_ $$aphotodissociation
000266997 6531_ $$adissociation
000266997 6531_ $$asequence
000266997 6531_ $$aleucine
000266997 6531_ $$aprotein
000266997 700__ $$aSolovyeva, Elizaveta M.
000266997 700__ $$aKopysov, Vladimir N.
000266997 700__ $$aPereverzev, Aleksandr Y.
000266997 700__ $$aLobas, Anna A.
000266997 700__ $$aMoshkovskii, Sergei A.
000266997 700__ $$aGorshkov, Mikhail V.
000266997 700__ $$aBoyarkin, Oleg V.$$0242817$$g104570
000266997 773__ $$k10$$j91$$q6709-6715$$tAnalytical Chemistry
000266997 8560_ $$fthomas.rizzo@epfl.ch
000266997 909C0 $$yApproved$$pLCPM$$xU10106$$mthomas.rizzo@epfl.ch$$zBorel, Alain$$0252096
000266997 909CO $$ooai:infoscience.epfl.ch:266997$$particle$$pSB
000266997 961__ $$amanon.velasco@epfl.ch
000266997 973__ $$aEPFL$$sPUBLISHED$$rREVIEWED
000266997 980__ $$aARTICLE
000266997 980__ $$aWoS
000266997 981__ $$aoverwrite