DETECTION AND PROPERTIES OF A-FACTOR-BINDING PROTEIN FROM STREPTOMYCES-GRISEUS
DETECTION AND PROPERTIES OF A-FACTOR-BINDING PROTEIN FROM STREPTOMYCES-GRISEUS
复制标题
DOI：
10.1128/jb.171.8.4298-4302.1989
复制
发表时间：
1989-08-01
影响因子：
3.2
通讯作者：
BEPPU, T
中科院分区：
文献类型：
--
作者：
MIYAKE, K;HORINOUCHI, S;BEPPU, T
化学合成了氚标记的 A 因子（2-异辛酰基-3R-羟甲基-γ-丁内酯）的光学活性形式，它是一种多效性自动调节剂，负责灰色链霉菌中链霉素的产生、链霉素抗性和孢子形成。通过使用放射性 A 因子，在该生物体的细胞质部分中检测到了 A 因子的结合蛋白。通过凝胶过滤测定，结合蛋白的表观分子量约为26,000。 Scatchard 分析表明 A 因子以 1:1 的摩尔比结合蛋白质，结合常数 Kd 为 0.7 nM。粗略估计每个基因组结合蛋白的数量为 37 个。 “诱导物质”维吉尼亚丁内酯 C (VB-C) 的结构与 A 因子非常相似，并且对于维吉尼亚链霉菌中维吉尼亚霉素的生产至关重要，它不会抑制结合。此外，在 S. griseus 中没有发现能够特异性结合 3H 标记的 VB-C 的蛋白质。结合观察到VB-C对于恢复A因子缺陷型灰色链霉菌突变体中链霉素产生或孢子形成几乎没有生物活性，这些结果表明结合蛋白具有严格的配体特异性。对天蓝色链霉菌 A3(2) 和浅青紫链霉菌中 A 因子结合蛋白的检查表明不存在任何特异性结合蛋白。
The optically active form of tritium-labeled A-factor (2-isocapryloyl-3R-hydroxymethyl-.gamma.-butyrolactone), a pleiotropic autoregulator responsible for streptomycin production, streptomycin resistance, and sporulation in Streptomyces griseus, was chemically synthesized. By using the radioactive A-factor, a binding protein for A-factor was detected in the cytoplasmic fraction of this organism. The binding protein had an apparent molecular weight of approximately 26,000, as determined by gel filtration. Scatchard analysis suggested that A-factor bound the protein in the molar ratio of 1:1 with a binding constant, Kd, of 0.7 nM. The number of the binding protein was roughly estimated to be 37 per genome. The "inducing material" virginiae butanolide C (VB-C), which has a structure very similar to that of A-factor and is essential for virginiamycin production in Streptomyces virginiae, did not inhibit binding. In addition, no protein capable of specifically binding 3H-labeled VB-C was found in S. griseus. Together with the observation that VB-C had almost no biological activity on the restoration of streptomycin production or sporulation in an A-factor-deficient mutant of S. griseus, these results indicated that the binding protein had a strict ligand specificity. Examination for an A-factor-binding protein in Streptomyces coelicolor A3(2) and Streptomyces lividans showed the absence of any specifically binding protein.