Crystallization of a nonclassical Kazal-type Carcinoscorpius rotundicauda serine protease inhibitor, CrSPI-1, complexed with subtilisin.

ABSTRACT: Serine proteases play a major role in host-pathogen interactions. The innate immune system is known to respond to invading pathogens in a nonspecific manner. The serine protease cascade is an essential component of the innate immune system of the horseshoe crab. The serine protease inhibitor CrSPI isoform 1 (CrSPI-1), a unique nonclassical Kazal-type inhibitor of molecular weight 9.3 kDa, was identified from the hepatopancreas of the horseshoe crab Carcinoscorpius rotundicauda. It potently inhibits subtilisin and constitutes a powerful innate immune defence against invading microbes. Here, the cloning, expression, purification and cocrystallization of CrSPI-1 with subtilisin are reported. The crystals diffracted to 2.6 A resolution and belonged to space group P2(1), with unit-cell paramete

SUBMITTER: Tulsidas SR 

PROVIDER: S-EPMC2675604 | biostudies-literature | 2009 May

REPOSITORIES: biostudies-literature