Lupeptin , also known as N – acetyl-L-lucyl-L-leucyl – L – arginine , is a naturally occurring protease inhibitor that can inhibit cysteine, serine and threonine peptidases. It is often used during in vitro experiments when a specific enzymatic reaction is being studied. When cells are lysed for these studies, proteases , many of which are contained within lysosomes, are released. These proteases, if freely present in the lysate, would destroy any products from the reaction being studied, and would make the experiment impractical. For example, leupeptin can be used in a calpain extraction to keep calpain from being hydrolyzed by specific proteases. The suggested concentration is 1-10 µM (0.5-5 µg/mL).
Lupeptin is an organic compound produced by actinomycetes , which inhibits serine , cysteine and threonine proteases . Leupeptin inhibits serine proteinases ( trypsin ( KI = 3.5 nM), plasmin ( KI = 3.4 nM), porcine kallikrein ), and cysteine proteinases ( papain , cathepsin B ( K I = 4.1 nM), Lys-C endoproteinase ). This is α- chymotrypsin or thrombindoes not interrupt. Leupeptin is a competitive transition state inhibitor and its inhibition can be relieved by an excess of substrate.
What is Leupeptin
Leupeptin, also known as N-acylyl-? L-leucyl- L-leucyl- L-argininal, a naturally occurring protease inhibitor that can inhibit cysteine, serine and threonine peptidases. It is often used during in vitro experiments when studying a specific enzymatic reaction. When cells are lysed for these studies, proteases, many of which are contained within lysosomes, are released. These proteases, if freely present in the lysate, would destroy any products from the reaction being studied, and would make the experiment indisputable. For example, leupeptin can be used in a calpain extraction to protect calpain from being hydrolyzed by specific proteases. The suggested concentration is 1-10 μM (0.5-5 μg/ml).
Lupeptin is an organic compound produced by actinomycetes that inhibits the serine, cysteine and thionine proteins. Leupeptin inhibits serine proteins (trypsin (Ki = 3.5 nM), plasmin (Ki = 3.4 nM), porcine kallikrein), and cysteine proteins (papain, cathepsin B (Ki = 4.1 nM), endoproteinase lys-C). It does not inhibit α-chymotrypsin or thrombin. Leupeptin is a competitive transition state inhibitor and its inhibition can be relieved by substrate overexpression.
Lupeptin is soluble in water (stable for 1 week at 4 °C and 1 month at −20 °C), ethanol, acetic acid and DMF.
