SACE_3986, a TetR family transcriptional regulator, negatively controls erythromycin biosynthesis in Saccharopolyspora erythraea
SACE_3986, a TetR family transcriptional regulator, negatively controls erythromycin biosynthesis in Saccharopolyspora erythraea
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SACE_3986，一种 TetR 家族转录调节因子，负向控制红霉素糖多孢菌的生物合成
DOI：
10.1007/s10295-014-1449-9
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发表时间：
2014-07-01
影响因子：
3.4
通讯作者：
Zhang, Buchang
中科院分区：
文献类型：
--
作者：
Wu, Panpan;Pan, Hui;Zhang, Buchang
红霉素是一种医学上重要的抗生素，由红多孢菌产生。不寻常的是，红霉素生物合成基因簇缺乏一个调控基因，其生物合成的调控仍然在很大程度上未知。本研究通过基因缺失、互补和过表达实验，鉴定了一个新的TetR家族转录调控因子SACE_3986，该因子对红霉素生物合成具有负调控作用。A226.将SACE_3986在工业菌株WB中进一步失活，其红霉素A产量比出发菌株平均提高了54.2%，表明SACE_3986在S.菜qRT-PCR分析表明，SACE_3986抑制了其相邻基因SACE_3985（其编码短链脱氢酶/还原酶）、红霉素生物合成基因eryAI和抗性基因ermE的转录。如通过EMSA分析所确定的，纯化的SACE_3986蛋白特异性结合至SACE_3985和SACE_3986之间的基因间区域，而其不结合至eryAI和ermE的启动子区域。此外，SACE_3985在A226中的过表达导致红霉素A产量增加至少32.6%。这些结果表明，SACE_3986是红霉素生物合成的负调控因子，而邻近基因SACE_3985是其靶基因之一。本研究为进一步利用SACE_3986和SACE_3985基因工程提高红霉素产量奠定了基础。菜
Erythromycin, a medically important antibiotic, is produced by Saccharopolyspora erythraea. Unusually, the erythromycin biosynthetic gene cluster lacks a regulatory gene, and the regulation of its biosynthesis remains largely unknown. In this study, through gene deletion, complementation and overexpression experiments, we identified a novel TetR family transcriptional regulator SACE_3986 negatively regulating erythromycin biosynthesis in S. erythraea A226. When SACE_3986 was further inactivated in an industrial strain WB, erythromycin A yield of the mutant was increased by 54.2 % in average compared with that of its parent strain, displaying the universality of SACE_3986 as a repressor for erythromycin production in S. erythraea. qRT-PCR analysis indicated that SACE_3986 repressed the transcription of its adjacent gene SACE_3985 (which encodes a short-chain dehydrogenase/reductase), erythromycin biosynthetic gene eryAI and the resistance gene ermE. As determined by EMSA analysis, purified SACE_3986 protein specifically bound to the intergenic region between SACE_3985 and SACE_3986, whereas it did not bind to the promoter regions of eryAI and ermE. Furthermore, overexpression of SACE_3985 in A226 led to enhanced erythromycin A yield by at least 32.6 %. These findings indicate that SACE_3986 is a negative regulator of erythromycin biosynthesis, and the adjacent gene SACE_3985 is one of its target genes. The present study provides a basis to increase erythromycin production by engineering of SACE_3986 and SACE_3985 in S. erythraea.