2pkc
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| , resolution 1.5Å | |||||||
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| Ligands: | |||||||
| Activity: | Peptidase K, with EC number 3.4.21.64 | ||||||
| Coordinates: | save as pdb, mmCIF, xml | ||||||
CRYSTAL STRUCTURE OF CALCIUM-FREE PROTEINASE K AT 1.5 ANGSTROMS RESOLUTION
OverviewOverview
Proteinase K from the fungus Tritirachium album Limber binds two Ca2+ ions, one strongly (Ca 1) and the other weakly (Ca 2). Removal of these cations reduces the stability of proteinase K as shown by thermal denaturation, but the proteolytic activity is unchanged. The x-ray structures of native and Ca(2+)-free proteinase K at 1.5-A resolution show that there are no cuts in the polypeptide backbone (i.e. no autolysis), Ca 1 has been replaced by Na+, while Ca 2 has been substituted by a water associated with a larger but locally confined structural change at that site. A small but concerted geometrical shift is transmitted from the Ca 1 site via eight secondary structure elements to the substrate recognition site (Gly100-Tyr104, and Ser132-Gly136) but not to the catalytic triad (Asp39,His69,Ser224). This is accompanied by positional changes of localized waters.
About this StructureAbout this Structure
2PKC is a Single protein structure of sequence from Engyodontium album. Full crystallographic information is available from OCA.
ReferenceReference
Crystal structure of calcium-free proteinase K at 1.5-A resolution., Muller A, Hinrichs W, Wolf WM, Saenger W, J Biol Chem. 1994 Sep 16;269(37):23108-11. PMID:8083213
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