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Published on: December 30, 2016
Crystallization and X-ray diffraction studies of crustacean proliferating cell nuclear antigen
Jesus S Carrasco-Miranda1, Cesar S Cardona-Felix, Alonso A Lopez-Zavala
1Centro de Investigación en Alimentación y Desarrollo, A.C. (CIAD), Carretera a Ejido La Victoria Km 0.6, Apartado Postal 1735, Hermosillo, Sonora 83304, Mexico.
Abstract:
Proliferating cell nuclear antigen (PCNA), a member of the sliding clamp family of proteins, interacts specifically with DNA replication and repair proteins through a small peptide motif called the PCNA-interacting protein or PIP box. PCNA is recognized as one of the key proteins involved in DNA metabolism. In the present study, the recombinant PCNA from Litopenaeus vannamei (LvPCNA) was heterologously overexpressed and purified using metal ion-affinity chromatography. Crystals suitable for diffraction grew overnight using the hanging-drop vapour-diffusion method. LvPCNA crystals belong to space group C2 with unit-cell parameters a=144.6, b=83.4, c=74.3 Å, β=117.6°. One data set was processed to 3 Å resolution, with an overall Rmeas of 0.09 and a completeness of 93.3%. Initial phases were obtained by molecular replacement using a homology model of LvPCNA as the search model. Refinement and structural analysis are underway. This report is the first successful crystallographic analysis of a marine crustacean decapod shrimp (L. vannamei) proliferating cell nuclear antigen.
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