简介:
简介:Disulfidebondsarevitalforproteinfunctions,butlocatingthelinkagesiteshasbeenachallengeinproteinchemistry,especiallywhenthequantityofasampleissmallorthecomplexityishigh.In2015,ourlaboratorydevelopedasensitiveandefficientmethodformappingproteindisulfidebondsfromsimpleorcomplexsamples(LuetaLinNatMethods12:329,2015).Thismethodisbasedonliquidchromatography-massspectrometry(LC-MS)andapowerfuldataanalysissoftwaretoolnamedpLink.Tofacilitateapplicationofthismethod,wepresentstep-by-stepdisulfidemappingprotocolsforthreetypesofsamples--purifiedproteinsinsolution,proteinsinSDS-PAGEgels,andcomplexproteinmix-turesinsolution.Theminimumamountofproteinrequiredforthismethodcanbeaslowasseveralhundrednanogramsforpurifiedproteins,ortensofmicrogramsforamixtureofhundredsofproteins.Theentireworkflow--fromsamplepreparationtoLC-MSanddataanalysis--isdescribedingreatdetail.Webelievethatthisprotocolcanbeeasilyimplementedinanylaboratorywithaccesstoafast-scanning,high-resolution,andaccurate-massLC-MSsystem.