2r33
From Proteopedia
Crystal structure of a Bowman-Birk inhibitor from Vigna unguiculata seeds
Overview
Different protease inhibitors including Bowman-Birk type (BBI) have been reported from the seeds of Vigna unguiculata. Protease isoinhibitors of double-headed Bowman-Birk type from the seeds of Vigna unguiculata have been purified and characterized. The BBI from Vigna unguiculata (Vu-BBI) has been found to undergo self-association to form very stable dimers and more complex oligomers, by size-exclusion chromatography and SDS-PAGE in the presence of urea. Many BBIs have been reported to undergo self-association to form homodimers or more complex oligomers in solution. Only one dimeric crystal structure of a BBI (pea-BBI) is reported to date. We report the three-dimensional structure of a Vu-BBI determined at 2.5 A resolution. Although, the inhibitor has a monomer fold similar to that found in other known structures of Bowman-Birk protease inhibitors, its quaternary structure is different from that commonly observed in this family. The structural elements responsible for the stability of monomer molecule and dimeric association are discussed. The Vu-BBI may use dimeric or higher quaternary association to maintain the physiological state and to execute its biological function.
About this Structure
This structure supersedes the now removed PDB entry 2ot6. Full crystallographic information is available from OCA.
Reference
Bowman-Birk protease inhibitor from the seeds of Vigna unguiculata forms a highly stable dimeric structure., Rao KN, Suresh CG, Biochim Biophys Acta. 2007 Oct;1774(10):1264-73. Epub 2007 Aug 3. PMID:17869196 Page seeded by OCA on Sun May 4 16:09:22 2008
