Metabolic engineering of Streptomyces coelicolor for enhanced prodigiosins (RED) production
Metabolic engineering of Streptomyces coelicolor for enhanced prodigiosins (RED) production
复制标题
天蓝色链霉菌的代谢工程可提高灵菌红素 (RED) 的产量。
DOI：
10.1007/s11427-017-9117-x
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发表时间：
2017-09-01
影响因子：
9.1
通讯作者：
Lu, Yinhua
中科院分区：
文献类型：
--
作者：
Liu, Panpan;Zhu, Hong;Lu, Yinhua
细菌浪子红素是一种红色的次生代谢产物，具有抗癌、抗疟、免疫抑制等多种活性，具有很大的医学应用潜力。在这项研究中，通过组合代谢工程，包括抑制基因ohkA的失活，放线菌素（ACT）和钙依赖性抗生素（CDA）生物合成基因簇（BGC）的缺失和RED BGC的多拷贝染色体整合，显著提高了彩链霉菌（Streptomyces colcololor）的红菌素（RED）的产生。结果表明，ohkA缺失导致RED产量比野生型菌株M145增加1倍。然后，基于Delta ohkA突变体（SBJ101），依次删除ACT和CDA bgc。为了实现多拷贝RED BGC的整合，在ACT和CDA BGC被删除的位置同时插入人工1断竖条C31 attB位点。得到的菌株SBJ102（单个ACT BGC缺失并插入一个人工attB位点）和SBJ103（两个BGC缺失并插入两个人工attB位点）的RED滴度分别比M145高1.9倍和6倍。最后，将整个RED BGC导入SBJ101 ~ SBJ103突变体中，产生了3个突变体（SBJ104 ~ SBJ106），染色体整合了1 ~ 3个RED BGC拷贝。其中，SBJ106产量最高，细胞干重达96.8 mg g(-1)，是M145的12倍。总的来说，本研究中采用的代谢工程策略对于构建高产量的菌株是非常有效的。
Bacterial prodigiosins are red-colored secondary metabolites with multiple activities, such as anticancer, antimalarial and immunosuppressive, which hold great potential for medical applications. In this study, dramatically enhanced prodigiosins (RED) production in Streptomyces coelicolor was achieved by combinatorial metabolic engineering, including inactivation of the repressor gene ohkA, deletion of the actinorhodin (ACT) and calcium-dependent antibiotic (CDA) biosynthetic gene clusters (BGCs) and multi-copy chromosomal integration of the RED BGC. The results showed that ohkA deletion led to a 1-fold increase of RED production over the wild-type strain M145. Then, the ACT and CDA BGCs were deleted successively based on the Delta ohkA mutant (SBJ101). To achieve multi-copy RED BGC integration, artificial I broken vertical bar C31 attB site(s) were inserted simultaneously at the position where the ACT and CDA BGCs were deleted. The resulting strains SBJ102 (with a single deletion of the ACT BGC and insertion of one artificial attB site) and SBJ103 (with the deletion of both BGCs and insertion of two artificial attB sites) produced 1.9- and 6-fold higher RED titers than M145, respectively. Finally, the entire RED BGC was introduced into mutants from SBJ101 to SBJ103, generating three mutants (from SBJ104 to SBJ106) with chromosomal integration of one to three copies of the RED BGC. The highest RED yield was from SBJ106, which produced a maximum level of 96.8 mg g(-1) cell dry weight, showing a 12-fold increase relative to M145. Collectively, the metabolic engineering strategies employed in this study are very efficient for the construction of high prodigiosin-producing strains.