1ym0: Difference between revisions

[[Image:1ym0.gif|left|200px]]<br /><applet load="1ym0" size="350" color="white" frame="true" align="right" spinBox="true"  

The earthworm fibrinolytic enzyme (EFE), belonging to a group of serine proteases with strong fibrinolytic activity, has been used in a mixture as an oral drug for prevention and treatment of thrombosis in East Asia. The EFE component b (EFE-b) is one of seven EFE components from Eisenia fetida, and among them it has nearly the highest fibrinolytic activity. Here, we report its crystal structure at a resolution of 2.06A. The structural analysis shows that EFE-b should be classified as a trypsin from earthworm. However, it is distinct from other trypsins. It is a two-chained protease with an N-terminal, pyroglutamated light chain and an N-glycosylated heavy chain. Furthermore, the heavy chain contains a novel structural motif, an eight-membered ring resulting from a disulfide bridge between two neighboring cysteine residues, and a cis peptide bond exists between these two cysteine residues. The crystal structure of EFE-b provides the structural basis for its high level of stability and reveals its complicated post-translational modifications in earthworm. This structure is the first reported for a glycosylated two-chained trypsin, which may provide useful clues to explain the origin and evolution of the chymotrypsin family.

1YM0 is a [http://en.wikipedia.org/wiki/Protein_complex Protein complex] structure of sequences from [http://en.wikipedia.org/wiki/Eisenia_fetida Eisenia fetida] with <scene name='pdbligand=MG:'>MG</scene> and <scene name='pdbligand=SO4:'>SO4</scene> as [http://en.wikipedia.org/wiki/ligands ligands]. Full crystallographic information is available from [http://oca.weizmann.ac.il/oca-bin/ocashort?id=1YM0 OCA].  

[[Category: An, X M.]]

[[Category: Chang, W R.]]

[[Category: Gui, L L.]]

[[Category: Zhang, J P.]]

''Page seeded by [http://oca.weizmann.ac.il/oca OCA ] on Thu Feb 21 16:06:42 2008''