Spraggon, Glen, Hornsby, Michael, Shipway, Aaron, Tully, David, Bursulaya, Badry, Danahay, Henry, Harris, Jennifer and Lesley, Scott (2009) Active site conformational changes of prostasin provide a new mechanism of protease regulation by divalent cations. Protein Science, 18 (5). pp. 1081-1094. ISSN 1469-896X

Abstract

Prostasin or human channel-activating protease 1 has been reported to play a critical role in the regulation of extracellular sodium ion transport via its activation of the epithelial cell sodium channel. Here, the structure of the extracellular portion of the membrane associated serine protease has been solved to high resolution in complex with a nonselective d-FFR chloromethyl ketone inhibitor, in an apo form, in a form where the apo crystal has been soaked with the covalent inhibitor camostat and in complex with the protein inhibitor aprotinin. It was also crystallized in the presence of the divalent cation Ca(+2). Comparison of the structures with each other and with other members of the trypsin-like serine protease family reveals unique structural features of prostasin and a large degree of conformational variation within specificity determining loops. Of particular interest is the S1 subsite loop which opens and closes in response to basic residues or divalent ions, directly binding Ca(+2) cations. This induced fit active site provides a new possible mode of regulation of trypsin-like proteases adapted in particular to extracellular regions with variable ionic concentrations such as the outer membrane layer of the epithelial cell.

Item Type:	Article
Related URLs:	http://www.ncbi.nlm.nih.gov/sites/entrez...
Additional Information:	archiving not allowed on institutional repository
Keywords:	serine protease; channel activating protein; X-ray structure conformational change; feedback regulation
Related URLs:	http://www.ncbi.nlm.nih.gov/sites/entrez...
Date Deposited:	14 Dec 2009 13:49
Last Modified:	31 Jan 2013 00:57
URI:	https://oak.novartis.com/id/eprint/1206