LeupeptinisareversIBLecompetitiveinhibitorofserineandthiolproteases.Ithasbeenreportedtoinhibitcalpain,cathepsinB,cathepsinsH,Landtrypsin.Typicalworkingconcentrationsareintherangeof10to100µM.Leupeptinappearstobeequallyeffectiveinanysaltform,adjustingforequivalentpeptidecontent.Thehemisulfatesaltswerethefirsttobecommerciallyavailable.Ofthethreesalts,thehydrochlorideistheleastinvasiveforminBIOLOGicalsettings.Noproblemorpreferenceforthetrifluoroacetate(TFA)formhasbeennoted;TFAisvolatile,socouldpossiblyberemovedbylyophilization.
Microbiallyproducedleupeptininhibitorwasfirstisolatedasamixtureoftwoverysimilarforms:acetyl-LeuLeu-Arg-alandpropionyl-Leu-Leu-Arg-al.Althoughthepropionylleupeptinisactiveasaninhibitortheacetylformismorecommonlyusedandisavailableinseveraldifferentforms. Leupeptin,becauseofitsaldehydegroup,mayactasareducingagentandthereforeinterfereinproteindeterminationssuchasLowryand,toalesserextent,Bradford.
Leupeptinstock(20mg/ml):LeupeptininMethanol.Prepareastockof20mg/mlinmethanol,Storeat-20°C.
AdditionalInformation
| Synonyms | Ac-Leu-Leu-Arginal |
|---|---|
| Product# | L-1165 |
| CAS# | 103476-89-7 |
| ChemicalName | Acetyl-Leu-Leu-Arg-al;Acetyl-L-leucyl-L-leucyl-L-argininal.hemisulfate |
| Formula | C20H38N6O4.0.5H2SO4 |
| MW | 475.6 |
| Appearance | Whitetofaintyellowpowder |
| Purity | >90%byHPLC,typically~>96.0% |
| Solubility | SolubleinH20(50mg/ml).Clearcolorlesstofaintyellowsolution |
| StorageTemp | -20°C |
