Regulation of the expression of the gene for chlorite dismutase (cld), located on the chlorate reduction composite transposon of the chlorate reducer Ideonella dechloratans, was studied. A 200 bp upstream sequence of the cld gene, and mutated and truncated versions thereof, was used in a reporter system in Escherichia coli. It was found that a sequence within this upstream region, which is nearly identical to the canonical FNR‐binding sequence of E. coli, is necessary for anaerobic induction of the reporter gene. Anaerobic induction was regained in an FNR‐deficient strain of E. coli when supplemented either with the fnr gene from E. coli or with a candidate fnr gene cloned from I. dechloratans. In vivo transcription of the suggested fnr gene of I. dechloratans was demonstrated by qRT‐PCR. Based on these results, the cld promoter of I. dechloratans is suggested to be a class II‐activated promoter regulated by an FNR‐type protein of I. dechloratans. No fnr‐type genes have been found on the chlorate reduction composite transposon of I. dechloratans, making anaerobic upregulation of the cld gene after a gene transfer event dependent on the presence of an fnr‐type gene in the recipient.

中文翻译：

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FNR型转录因子可诱导来自小球藻小球藻亚氯酸歧化酶的基因异源表达。

研究了位于氯酸盐还原剂小球藻（Ideonella dechloratans）的氯酸盐还原复合转座子上的亚氯酸盐歧化酶（cld）基因表达的调控。cld基因的200bp上游序列及其突变和截短形式被用于大肠杆菌的报道系统中。发现该上游区域内的序列与E的标准FNR结合序列几乎相同。大肠杆菌是厌氧诱导报告基因所必需的。补充了来自FNR的fnr基因后，在FNR缺陷型大肠杆菌中恢复了无氧诱导大肠杆菌或具有从脱氯衣藻中克隆的候选fnr基因。所建议的体内转录FNR基因I. dechloratans通过qRT-PCR证实。基于这些结果，在CLD的启动子I. dechloratans建议是一个II类激活的启动子通过的FNR型蛋白调节I. dechloratans。没有FNR型基因已被发现的氯酸盐减少复合转座子我。dechloratans，使厌氧上调CLD基因的基因转移事件之后依赖于存在FNR受体基因类型。