Effect of increased dosage of the ML-236B (compactin) biosynthetic gene cluster on ML-236B production in Penicillium citrinum
Effect of increased dosage of the ML-236B (compactin) biosynthetic gene cluster on ML-236B production in Penicillium citrinum
复制标题
DOI：
10.1007/s00438-002-0736-8
复制
发表时间：
2002-09-01
影响因子：
3.1
通讯作者：
Yoshikawa, H
中科院分区：
文献类型：
--
作者：
Abe, Y;Suzuki, T;Yoshikawa, H
负责ML-236 B（compactin）生物合成的基因簇最近已从P. citrinum No.41520中鉴定出来。在这里，我们描述了ML-236 B生产菌株是如何改进使用粘粒介导的重组技术。将含有9个ML-236 B生物合成基因中的7个的粘粒pML 48导入桔黄青霉41520中，产生产生ML-236 B量增加的转化体。Southern分析显示，pML 48已通过同源重组事件并入，并且所有高产者均具有七个基因（mlcA-mlcF和mlcR）中的每一个的两个拷贝，这表明生物合成基因簇的剂量增加是ML-236 B产量增强的原因。另一方面，还获得了ML-236 B滴度降低的各种突变体。一个这样的突变体，命名为T48.28，这是更敏感的ML-236 B比亲本菌株的表征，表明ML-236 B生物合成基因，mlcD，它编码一个假定的HMG-CoA还原酶，参与赋予抗性ML-236 B。
The gene cluster responsible for ML-236B (compactin) biosynthesis has recently been characterized from P. citrinum No. 41520. Here, we describe how the ML-236B-producing strain was improved using a cosmid-mediated recombination technique. The introduction of the cosmid pML48, which contains seven of the nine ML-236B biosynthetic genes, into P. citrinum No. 41520 resulted in transformants which produced increased amounts of ML-236B. Southern analysis showed that pML48 had been incorporated by a homologous recombination event, and all high producers possessed two copies of each of the seven genes, mlcA-mlcF and mlcR, suggesting that increased dosage of the biosynthetic gene cluster was responsible for the enhanced production of ML-236B. On the other hand, various kinds of mutants with decreased titers of ML-236B were also obtained. Characterization of one such mutant, designated as T48.28, which was more sensitive to ML-236B than the parental strain, suggested that one of the ML-236B biosynthetic genes, mlcD, which encodes a putative HMG-CoA reductase, was involved in conferring resistance to ML-236B.