Characterization of the Aspergillus ochraceoroseus aflatoxin/sterigmatocystin biosynthetic gene cluster
Characterization of the Aspergillus ochraceoroseus aflatoxin/sterigmatocystin biosynthetic gene cluster
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DOI：
10.3852/08-173
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发表时间：
2009-05-01
期刊：
影响因子：
2.8
通讯作者：
Klich, M. A.
中科院分区：
文献类型：
--
作者：
Cary, J. W.;Ehrlich, K. C.;Klich, M. A.
据报道，黄曲霉属的黄曲霉组、巢曲霉组和新提出的赭曲霉组（由赭曲霉和A.兰贝利。与Flavi组不同，A. ochraceoroseus和A.兰氏菌已显示积累黄曲霉毒素（AF）和黄曲霉毒素前体杂色曲霉素（ST）。尽管形态上不同。从. nidulans，A. ochraceorose，us AF/ST基因和AF/ST产生的生理特性表明，A. ochraceoroseus与A. nidulans比A.黄的知道A. nidulans ST基因簇与A.黄曲霉AF基因簇，确定了黄曲霉AF/ST生物合成簇的遗传结构。赭色的通过基因步移技术获得的重叠λ克隆和基因组PCR片段的测序表明，A.赭曲霉AF/ST基因簇的组织结构与A. nidulans ST基因簇期望从aflN到aflW的区域直接位于aflC的上游并且处于相反方向，使得aflW代表簇的远端，aflY代表簇的近端。助理ochraceoroseus簇基因与A. nidulans ST簇基因同源物。A的转化。nidulans aflR突变体与A. ochraceoroseus aflR恢复了A. nidulans转化体。PCR扩增A. rembellii基因组DNA分析表明，AF/ST基因簇的组成方式与A.赭色的
Production of carcinogenic aflatoxins has been reported from members of Aspergillus section Flavi, Aspergillus section Nidulantes and a newly proposed Aspergillus section Ochraceorosei that consists of Aspergillus ochraceoroseus and A. rambellii. Unlike members of section Flavi, A. ochraceoroseus and A. rambellii have been shown to accumulate both aflatoxin (AF) and the aflatoxin precursor sterigmatocystin (ST). Alhough morphologically distinct. from A. nidulans, molecular characterization of A. ochraceorose,us AF/ST genes and physiological characteristics of AF/ST production indicated that A. ochraceoroseus is more closely related to A. nidulans than to A. flavus. Knowing that the A. nidulans ST gene cluster is organized differently from the A. flavus AF gene cluster, we determined the genetic organization of the AF/ST biosynthetic cluster in A. ochraceoroseus. Sequencing of overlapping lambda clones and genomic PCR fragments obtained by gene-walking techniques demonstrated that the A. ochraceoroseus AF/ST gene cluster is organized Much like the A. nidulans ST gene Cluster expect that the region from aflN to aflW is located directly upstream of aflC and in reverse orientation Such that aflW represents the distal end and aflY the proximal end of the cluster. The A. ochraceoroseus cluster genes demonstrated 62-76% nucleotide identity to their A. nidulans ST cluster gene homologs. Transformation of an A. nidulans aflR Mutant with the A. ochraceoroseus aflR restored ST production in A. nidulans transformants. PCR amplification of A. rembellii genomic DNA demonstrated that the AF/ST gene Cluster is organized in the same manner as that of A. ochraceoroseus.