Protein Domain : Serpin, conserved site IPR023795

Type	Conserved_site
Description	Serpins (SERine Proteinase INhibitors) belong to MEROPS inhibitor family I4, clan ID. Most serpin family members are indeed serine protease inhibitors, but several have additional cross-class inhibition functions and inhibit cysteine protease family members such as the caspases and cathepsins [ , ]. Others, such as ovalbumin, are incapable of protease inhibition and serve other functions []. Serpins share a highly conserved core structure that is critical for their functioning as serine protease inhibitors [ ]. Inhibitory serpins comprise several α-helix and β-strandstogether with an external reactive centre loop (RCL) containing the active site recognised by the target enzyme. Serpins form covalent complexes with target proteases. Their mechanism of protease inhibition is known as irreversible "trapping", in which a rapid conformational change traps the cognate protease in a covalent complex. This entry represents a conserved site for the Serpin family of proteins, centred on a well conserved Pro-Phe sequence which is found ten to fifteen residues on the C-terminal side of the reactive bond.
Short Name	Serpin_CS