||Recombinanthuman HtrA3, expressed in insect cells with a C-terminal His-tag and is purifiedfrom insect cell culture supernatants. The calculated Mr of secreted HtrA3 is47,8 kDa.
||HtrA3 isa secreted human serine protease is supposed to form oligomers of identicalprotein chains as revealed by X-ray analysis for the bacterial HtrA proteinDegP. Polypeptide chains of human HtrA3 consist of several domains: AnN-terminal insulin-like growth factor domain is followed by a Kazal-typeserine protease inhibitor domain, a linker region, a trypsin-like proteasedomain and a PDZ domain. The function of HtrA3 is a probable serine protease.No information is available yet on physiological substrates or interactingproteins.
||RecombinantHtrA3 appears as a major protein of 50 kDa in SDS-PAGE (> 70 % of totalprotein).Minor bands of HtrA3 fragments may be visible in the enzyme preparation.
||HtrA3 issolublized in 150 mM NaCl, 5 mM CaCl2, 0.05 % Brij-35, 50 mM imidazol, 50 mMTris-HCl, pH 7.5.
||RecombinantHtrA3 allows detailed studies of the structure and function of this protease.The enzyme is used to screen for inhibitors and to characterize inhibitoractions. Recombinant HtrA3 can also serve as standard in enzymatic andimmunochemical assays.
||Recombinanthuman HtrA3 is stable until the expiry date given on the label when stored at -70 °C.Repeated freezing and thawing should be avoided.