Heinemann U, Wernitz M, Pähler A, Saenger W, Menke G, Rüterjans H
Eur J Biochem. 1980 Aug;109(1):109-14. doi: 10.1111/j.1432-1033.1980.tb04774.x.
Ribonuclease T1 was crystallized under various conditions. Form I crystals were produced by microdialysis against 53% (v/v) 2-methyl-2,4-pentanediol in 0.01 M sodium acetate, 0.05% 2'-guanylic acid (2'GMP) and 0.02% NaN3 (pH 6.2-7.2). These crystals are tetragonal, space group P41212 and contain two molecules per asymmetric unit; cell dimensions are a = b = 5.86 nm, c = 13.28 nm. Form IIa and form IIb crystals were obtained by microdialysis from a buffer of 0.01-0.05 M sodium acetate, 0.25-0.5% 2'GMP, 0.02% NaN3 and 2-5 mM calcium acetate (pH 4.0-4.4) in the presence of 50-75% (v/v) 2-methyl-2,4-pentanediol. These crystals are orthorhombic, space group P212121, and contain one molecule per asymmetric unit; cell dimensions are a = 4.66 nm, b = 5.02 nm, c = 4.04 nm (form I) and alpha = 4.44 nm, b = 5.00 nm, c = 4.03 nm (form II). Using high-performance liquid chromatography, it could be shown for all crystal forms that 2'-GMP is bound in the crystals. The molecular ratio between RNase T1 and 2'GMP was 0.9 for form II crystals and thus agreed with a 1:1 enzyme-nucleotide complex. Heavy-atom derivatives were produced with lead acetate for form IIa crystals and with uranyl acetate for from IIb crystals. Three-dimensional X-ray analysis of the RNase-T1 x 2'GMP complex is under way.
核糖核酸酶T1在各种条件下结晶。I型晶体是通过在含有0.01M醋酸钠、0.05% 2'-鸟苷酸（2'GMP）和0.02%叠氮化钠（pH 6.2 - 7.2）的53%（v/v）2-甲基-2,4-戊二醇中进行微量透析产生的。这些晶体为四方晶系，空间群P41212，每个不对称单元包含两个分子；晶胞参数为a = b = 5.86 nm，c = 13.28 nm。IIa型和IIb型晶体是通过在含有50 - 75%（v/v）2-甲基-2,4-戊二醇的0.01 - 0.05M醋酸钠、0.25 - 0.5% 2'GMP、0.02%叠氮化钠和2 - 5mM醋酸钙（pH 4.0 - 4.4）的缓冲液中进行微量透析获得的。这些晶体为正交晶系，空间群P212121，每个不对称单元包含一个分子；晶胞参数为a = 4.66 nm，b = 5.02 nm，c = 4.04 nm（I型）和a = 4.44 nm，b = 5.00 nm，c = 4.03 nm（II型）。使用高效液相色谱法可以证明，对于所有晶体形式，2'-GMP都结合在晶体中。II型晶体中核糖核酸酶T1与2'GMP的分子比为0.9，因此与1:1的酶 - 核苷酸复合物相符。用醋酸铅制备了IIa型晶体的重原子衍生物，用醋酸铀酰制备了IIb型晶体的重原子衍生物。核糖核酸酶T1×2'GMP复合物的三维X射线分析正在进行中。
