Crystallization and preliminary crystallographic characterization of the extrinsic PsbP protein of photosystem II from Spinacia oleracea

Institute of Systems Biology and Ecology, Academy of Sciences of Czech Republic, Zámek 136, 37333 Nové Hrady, Czech Republic.
Acta Crystallographica Section F Structural Biology and Crystallization Communications (Impact Factor: 0.57). 03/2009; 65(Pt 2):111-5. DOI: 10.1107/S1744309108040578
Source: PubMed

ABSTRACT Preliminary X-ray diffraction analysis of the extrinsic PsbP protein of photosystem II from spinach (Spinacia oleracea) was performed using N-terminally His-tagged recombinant PsbP protein overexpressed in Escherichia coli. Recombinant PsbP protein (thrombin-digested recombinant His-tagged PsbP) stored in bis-Tris buffer pH 6.00 was crystallized using the sitting-drop vapour-diffusion technique with PEG 550 MME as a precipitant and zinc sulfate as an additive. SDS-PAGE analysis of a dissolved crystal showed that the crystals did not contain the degradation products of recombinant PsbP protein. PsbP crystals diffracted to 2.06 A resolution in space group P2(1)2(1)2(1), with unit-cell parameters a = 38.68, b = 46.73, c = 88.9 A.

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    • "As described in Methods, the recombinant PsbP protein from spinach was crystallized and the crystals used for x-ray analysis under conditions slightly different from those reported previously [35] in order to control crystal size for synchrotron analysis. Figure 2A shows the protein structural model resulting from analysis of diffraction data extending to 1.98 Å; statistics from the structural analysis are presented in Table 1. "
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