Suzuki Toshihiro, Mochizuki Susumu, Yamamoto Shouji, Arakawa Kenji, Kinashi Haruyasu
Department of Molecular Biotechnology, Graduate School of Advanced Sciences of Matter, Hiroshima University, Japan.
Biosci Biotechnol Biochem. 2010;74(4):819-27. doi: 10.1271/bbb.90927. Epub 2010 Apr 7.
Transcription and complementation experiments were carried out to analyze the regulatory hierarchy of two Streptomyces antibiotic regulatory protein (SARP) genes, srrY and srrZ, in the gamma-butyrolactone (GB)-dependent regulatory cascade in Streptomyces rochei 7434AN4. The srrY gene was transcribed in the srrZ mutant, while the srrZ gene was not in the srrY mutant. The SrrY protein was specifically bound to the promoter region of srrZ, where a possible SARP binding sequence was identified 26 bp upstream of the -10 sequence. Deletion of the repeat sequences from this region abolished its SrrY binding activity. In addition, complementation of srrZ restored lankamycin production in the srrY mutant. All of these results confirm that the SARP gene srrY directly regulates expression of the second SARP gene srrZ in a positive manner. This study gave the first confirmation of direct regulation of two SARP genes in the GB-dependent regulatory cascade in Streptomyces.
进行了转录和互补实验，以分析罗氏链霉菌7434AN4中γ-丁内酯（GB）依赖性调控级联反应中两个链霉菌抗生素调控蛋白（SARP）基因srrY和srrZ的调控层次。srrY基因在srrZ突变体中被转录，而srrZ基因在srrY突变体中不被转录。SrrY蛋白特异性结合到srrZ的启动子区域，在-10序列上游26 bp处鉴定出一个可能的SARP结合序列。从该区域删除重复序列消除了其SrrY结合活性。此外，srrZ的互补恢复了srrY突变体中兰卡霉素的产生。所有这些结果证实，SARP基因srrY以正向方式直接调节第二个SARP基因srrZ的表达。这项研究首次证实了链霉菌中GB依赖性调控级联反应中两个SARP基因的直接调控。
