3caa
CLEAVED ANTICHYMOTRYPSIN A347R
OverviewOverview
A hallmark of serpin function is the massive beta-sheet rearrangement involving the insertion of the cleaved reactive loop into beta-sheet A as strand s4A. This structural transition is required for inhibitory activity. Small hydrophobic residues at P14 and P12 positions of the reactive loop facilitate this transition, since these residues must pack in the hydrophobic core of the cleaved serpin. Despite the radical substitution of arginine at the P12 position, the crystal structure of cleaved A347R antichymotrypsin reveals full strand s4A insertion with normal beta-sheet A geometry; the R347 side chain is buried in the hydrophobic protein core. In contrast, the structure of cleaved P14 T345R antichymotrypsin reveals substantial yet incomplete strand s4A insertion, without burial of the R345 side chain.
DiseaseDisease
Known disease associated with this structure: Alpha-1-antichymotrypsin deficiency OMIM:[107280], Cerebrovascular disease, occlusive OMIM:[107280]
About this StructureAbout this Structure
3CAA is a Protein complex structure of sequences from Homo sapiens. This structure supersedes the now removed PDB entry 2caa. Full crystallographic information is available from OCA.
ReferenceReference
Arginine substitutions in the hinge region of antichymotrypsin affect serpin beta-sheet rearrangement., Lukacs CM, Zhong JQ, Plotnick MI, Rubin H, Cooperman BS, Christianson DW, Nat Struct Biol. 1996 Oct;3(10):888-93. PMID:8836107 Page seeded by OCA on Sun May 4 21:30:47 2008