AI Article Synopsis
- A calcium-binding protein from Entamoeba histolytica was purified from an E. coli clone using specific chromatography techniques.
- The protein contains four EF-hand motifs and was crystallized with the hanging-drop method using MPD as a precipitant.
- X-ray diffraction revealed the crystals belong to the hexagonal space group P6122, and its structure is likely similar to calmodulin based on preliminary molecular-replacement analysis.
Article Abstract
A calcium-binding protein (CaBP) of Entamoeba histolytica was purified from an E. coli recombinant clone carrying the CaBP gene in a pET-3c expression vector using anion-exchange and size-exclusion chromatography. Examination of the amino-acid sequence of the recombinant protein suggested that it has four independent EF-hand motifs. The protein dissolved in cacodylate buffer was crystallized using the hanging-drop method with 2-methylpentane-2,4-diol (MPD) as the precipitant. X-ray diffraction data have been collected on these crystals using a MAR Research imaging-plate detector system attached to a Rigaku RU200 rotating-anode X-ray generator. The crystals belong to the hexagonal space group P6122 with unit-cell dimensions of a = b = 96.21, c = 65.48 A. Preliminary molecular-replacement computations suggest that the structure of this protein is likely to be similar to that of calmodulin (CAM).
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| http://dx.doi.org/10.1107/s0907444998001759 | DOI Listing |
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