1EYX

CRYSTAL STRUCTURE OF R-PHYCOERYTHRIN AT 2.2 ANGSTROMS

Summary for 1EYX

• Entry DOI: 10.2210/pdb1eyx/pdb
• Descriptor: R-PHYCOERYTHRIN, SULFATE ION, BILIVERDINE IX ALPHA, ... (8 entities in total)
• Functional Keywords: r-phycoerythrin, macroseeding, twin, protein structure, sequences, phycobiliprotein, red algae, photosynthesis
• Biological source: Gracilaria chilensis; More
• Cellular location: Plastid, chloroplast thylakoid membrane; Peripheral membrane protein; Stromal side: Q7SIG0 Q7SIF9
• Total number of polymer chains: 6
• Total formula weight: 80100.52

Authors

Contreras-Martel, C.,Legrand, P.,Piras, C.,Vernede, X.,Martinez-Oyanedel, J.,Bunster, M.,Fontecilla-Camps, J.C. (deposition date: 2000-05-09, release date: 2000-11-22, Last modification date: 2023-08-09)

Primary citation

Contreras-Martel, C.,Martinez-Oyanedel, J.,Bunster, M.,Legrand, P.,Piras, C.,Vernede, X.,Fontecilla-Camps, J.C.
Crystallization and 2.2 A resolution structure of R-phycoerythrin from Gracilaria chilensis: a case of perfect hemihedral twinning.
Acta Crystallogr.,Sect.D, 57:52-60, 2001

PubMed Abstract: R-phycoerythrin, a light-harvesting component from the red algae Gracilaria chilensis, was crystallized by vapour diffusion using ammonium sulfate as precipitant agent. Red crystals grew after one week at 293 K and diffracted to 2.70 A resolution. Three serial macroseeding assays were necessary to grow a second larger crystal to dimensions of 0.68 x 0.16 x 0.16 mm. This crystal diffracted to 2.24 A resolution using synchrotron radiation at beamline BM14 of the European Synchrotron Radiation Facility (ESRF) at Grenoble, France and was used for structure determination. Data were collected at 100 K to a completeness of 98.6%. The crystal was trigonal, space group R3, with unit-cell parameters a = b = 187.3, c = 59.1 A, alpha = beta = 90, gamma = 120 degrees. Data treatment using the CCP4 suite of programs indicated that the crystal was twinned ((I(2))/(I)(2) = 1.41). Molecular replacement was performed with AMoRe using the R-phycoerythrin from Polysiphonia urceolata [Chang et al. (1996), J. Mol. Biol. 249, 424-440] as a search model. In order to overcome the twinning problem, SHELX97 was used for the crystallographic refinement. The twin fraction was 0.48, indicating a nearly perfect hemihedrally twinned crystal. The final R(work) and R(free) factors are 0.16 and 0.25, respectively. All the residues and chromophores of the alpha- and beta-chains are well defined in the electron-density maps. Some residues belonging to the gamma-linker are also recognizable.

PubMed: 11134927
DOI: 10.1107/S0907444900015274

Experimental method

X-RAY DIFFRACTION (2.25 Å)