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从条斑紫菜(Porphyra yezoensis)中提取的天然R-藻红蛋白,在pH为7.5的0.05mol/L磷酸钾缓冲液中分子量为230000(23000)D;吸收光谱最大峰位于565nm,498nm及肩峰540nm;荧光发射最大峰位于578nm,正在进行中的X射线单晶衍射研究表明它结晶于菱面体空间群R3,按六方格子指标的晶胞参数为:a=6=187.5(2.5)和c=60.0(3.0);测定了晶体和母液的密度分别是1.215g/cm~3和1.070g/cm~3;蛋白质占据晶体体积的51.5％;讨论了在菱面体格子中晶体学不对称单位内可能包含分子量不大于8×10~4D的(αβ)_2的二聚体,在六方晶胞中三个直径为108,高为60的圆柱体状的分子,按空间群的对称性堆积成晶体。
The native R-phycoerythrin extracted from Porphyra yezoensis has a molecular weight of 230,000 (23,000) D in 0.05 mol / L potassium phosphate buffer at pH 7.5; the maximum absorption peak at 565 nm, 498 nm and shoulder Peak at 540 nm; the maximum peak of fluorescence emission is at 578 nm; the ongoing X-ray single crystal diffraction study shows that it crystallizes in the rhombohedral space group R3 with unit cell parameters of a = 6 = 187.5 (2.5) and c = 60.0 (3.0). The densities of the crystal and the mother liquor were determined to be 1.215 g / cm ~ 3 and 1.070 g / cm ~ 3 respectively. The protein accounted for 51.5% of the crystal volume. The intracrystalline asymmetry units May contain dimers of (αβ) _2 having a molecular weight of not more than 8 × 10 -4 D. Three hexagonal units of three 108-diameter and 60-height cylinders accumulate into crystals in space group symmetry .