Calderihabitans maritimus KKC1 is a thermophilic, carbon monoxide (CO)-utilizing, hydrogen-evolving bacterium that harbors seven cooS genes for anaerobic CO dehydrogenases and six hyd genes for [NiFe] hydrogenases and capable of using a variety of electron acceptors coupled to CO oxidation. To understand the relationships among these unique features and the transcriptional adaptation of the organism to CO, we performed a transcriptome analysis of C. maritimus KKC1 grown under 100% CO and N₂ conditions. Of its 3114 genes, 58 and 32 genes were significantly upregulated and downregulated in the presence of CO, respectively. A cooS–ech gene cluster, an “orphan” cooS gene, and bidirectional hyd genes were upregulated under CO, whereas hydrogen-uptake hyd genes were downregulated. Transcriptional changes in anaerobic respiratory genes supported the broad usage of electron acceptors in C. maritimus KKC1 under CO metabolism. Overall, the majority of the differentially expressed genes were oxidoreductase-like genes, suggesting metabolic adaptation to the cellular redox change upon CO oxidation. Moreover, our results suggest a transcriptional response mechanism to CO that involves multiple transcription factors, as well as a CO-responsive transcriptional activator (CooA). Our findings shed light on the diverse mechanisms for transcriptional and metabolic adaptations to CO in CO-utilizing and hydrogen-evolving bacteria.

中文翻译：

---

通过转录组分析揭示了嗜热的，利用一氧化碳，放氢的细菌Calderihabitans maritimus KKC1中一氧化碳的依赖转录变化。

Calderihabitans maritimus KKC1是一种利用嗜热性，一氧化碳（CO）分解氢的细菌，具有七个厌氧性CO脱氢酶的cooS基因和六个[NiFe]氢化酶的hyd基因，并且能够使用多种与CO氧化偶联的电子受体。为了理解这些独特的功能和有机体对CO的转录适配之间的关系，我们进行的转录组分析C. maritimus 100％CO和N下生长KKC1 _2分的条件。在CO的存在下，在其3114个基因中，分别有58个和32个基因显着上调和下调。甲库斯-ECH基因簇，一个“孤儿”库斯CO下双向基因和双向hyd基因上调，而氢吸收hyd基因下调。在厌氧呼吸的基因的转录变化支承在电子受体的广泛使用C. maritimus KKC1下CO代谢。总体而言，大多数差异表达的基因是类似氧化还原酶的基因，表明在CO氧化后代谢适应于细胞氧化还原变化。此外，我们的结果表明，涉及多种转录因子的CO转录响应机制以及CO响应转录激活因子（CooA）。我们的发现揭示了利用CO和产氢细菌中CO转录和代谢适应的多种机制。