DNA-BINDING AND ENZYMATIC DOMAINS OF THE BIFUNCTIONAL BIOTIN OPERON REPRESSOR (BIRA) OF ESCHERICHIA-COLI
DNA-BINDING AND ENZYMATIC DOMAINS OF THE BIFUNCTIONAL BIOTIN OPERON REPRESSOR (BIRA) OF ESCHERICHIA-COLI
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DOI：
10.1016/0378-1119(86)90189-7
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发表时间：
1986-01-01
期刊：
影响因子：
3.5
通讯作者：
OTSUKA, AJ
中科院分区：
文献类型：
--
作者：
BUONCRISTIANI, MR;HOWARD, PK;OTSUKA, AJ
大肠杆菌中生物素生物合成 (bio) 操纵子的负调控是由双功能 birA 基因产物介导的，该基因产物充当生物阻遏物和生物素激活酶。采用对 birA 基因 18 个突变的核苷酸序列分析来研究 BirA 蛋白的 DNA 结合和酶功能。结果表明，321-aa BirA 蛋白中氨基酸 (aa) 位点 18 至 39 的预测螺旋-转角-螺旋结构可能负责序列特异性 DNA 结合，而影响生物素激活的温度敏感突变则在氨基酸位点 83-119 和 189-235 的两个区域中发现。
The negative regulation of the biotin biosynthetic (bio) operon in Escherichia coli is mediated by the bifunctional birA gene product, which serves as the bio repressor and biotin-activating enzyme. Nucleotide sequence analysis of 18 mutations in the birA gene was employed to study the DNA-binding and enzymatic functions of the BirA protein. The results indicate that a predicted helix-turn-helix structure, from amino acid (aa) positions 18 to 39 within the 321-aa BirA protein, may be responsible for sequence-specific DNA binding, whereas the temperature-sensitive mutations affecting biotin activation are found in two regions from aa positions 83-119 and 189-235.