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运用基因工程技术,将耐热邻苯二酚2,3-双加氧酶（TC23O）分子中的甲硫氨酸（Met）全部置换为甲硒氨酸（SeMet）.培养出甲硒氨酸置换的耐热邻苯二酚2,3-双加氧酶（SeMet-TC23O）的晶体.利用同步辐射光源收集了SeMet-TC23O 晶体的X射线衍射数据,应用多波长反常散射方法测定了TC23O0.3mm的晶体结构.结果显示,TC23O分子为同源四聚体结构,每个单体由相对独立的N-端结构域（1～153位氨基酸残基）和C-端结构域（153～319位氨基酸残基）构成.每个结构域含有两个在此类酶中具有特征性的βαβββ结构花样.两个结构域可根据分子内非晶体学对称轴近似叠合.
Gene methionine (Met) was replaced by methionine (Met) in the thermostable catechol 2,3-dioxygenase (TC23O) gene using genetic engineering techniques. Displacement of thermostable catechol 2,3-dioxygenase (SeMet-TC23O) crystals by using synchrotron radiation source collected X-ray diffraction data SeMet-TC23O crystal, the application of multi-wavelength anomalous scattering method for the determination of TC23O0. 3mm crystal structure.The results showed that the TC23O molecule is a homotetrameric structure, each monomer consists of relatively independent N-terminal domain (amino acid residues 1 to 153) and C-terminal domain (153 ~ 319 Position amino acid residues.) Each domain contains two βββββ structural motifs characteristic of this class of enzymes.The two domains can be approximately superposed according to the intramolecular non-crystallographic axis of symmetry.