Preliminary x-ray crystallographic analysis of centrin from ciliate Euplotes octocarinatus.

Centrins are four-EF-hand Ca(2+)-binding proteins, which belong to the CaM super family. The centrin from ciliate Euplotes Octocarinatus has been expressed in Escherichia coli, purified and crystallized using the hanging-drop method. Rod-like crystals were grown and diffracted to 2.0 angstroms. The crystals belong to space group P2(1)2(1)2(1) and the unit-cell parameters are a=34.442 angstroms, b=48.954 angstroms, c=72.583 angstroms.