Data_Sheet_1_Genomic potential and physiological characteristics of C1 metabolism in novel acetogenic bacteria.pdf

Acetogenic bacteria can utilize C1 compounds, such as carbon monoxide (CO), formate, and methanol, via the Wood-Ljungdahl pathway (WLP) to produce biofuels and biochemicals. Two novel acetogenic bacteria of the family Eubacteriaceae ES2 and ES3 were isolated from Eulsukdo, a delta island in South Korea. We conducted whole genome sequencing of the ES strains and comparative genome analysis on the core clusters of WLP with Acetobacterium woodii DSM1030T and Eubacterium limosum ATCC8486T. The methyl-branch cluster included a formate transporter and duplicates or triplicates copies of the fhs gene, which encodes formyl-tetrahydrofolate synthetase. The formate dehydrogenase cluster did not include the hydrogenase gene, which might be replaced by a functional complex with a separate electron bifurcating hydrogenase (HytABCDE). Additionally, duplicated copies of the acsB gene, encoding acetyl-CoA synthase, are located within or close to the carbonyl-branch cluster. The serum bottle culture showed that ES strains can utilize a diverse range of C1 compounds, including CO, formate, and methanol, as well as CO2. Notably, ES2 exhibited remarkable resistance to high concentrations of C1 substrates, such as 100% CO (200 kPa), 700 mM formate, and 500 mM methanol. Moreover, ES2 demonstrated remarkable growth rates under 50% CO (0.45 h−1) and 200 mM formate (0.34 h−1). These growth rates are comparable to or surpassing those previously reported in other acetogenic bacteria. Our study introduces novel acetogenic ES strains and describes their genetic and physiological characteristics, which can be utilized in C1-based biomanufacturing.

产乙酸菌（Acetogenic bacteria）可通过Wood-Ljungdahl途径（Wood-Ljungdahl pathway, WLP）利用一氧化碳（CO）、甲酸与甲醇等C1化合物合成生物燃料与生物化学品。本研究从韩国三角洲岛屿乙淑岛（Eulsukdo）中分离得到两株隶属于真杆菌科（Eubacteriaceae）的新型产乙酸菌ES2与ES3，并对这两株ES菌株开展全基因组测序，同时以伍德乙酸杆菌（Acetobacterium woodii DSM1030^T）和粘液真杆菌（Eubacterium limosum ATCC8486^T）为参照菌株，对WLP的核心基因簇进行比较基因组分析。分析结果显示，甲基分支基因簇包含1个甲酸转运蛋白，以及编码甲酰四氢叶酸合成酶的fhs基因的双拷贝或三拷贝；甲酸脱氢酶基因簇未包含氢化酶基因，推测其可由独立的电子分岔氢化酶（HytABCDE）构成的功能复合物替代。此外，编码乙酰辅酶A合成酶的acsB基因的双拷贝位于羰基分支基因簇内部或其邻近区域。血清瓶培养实验表明，ES菌株可利用包括CO、甲酸、甲醇及二氧化碳（CO2）在内的多种C1化合物。值得注意的是，ES2对高浓度C1底物表现出优异的耐受性，例如100%一氧化碳（200 kPa）、700 mM甲酸与500 mM甲醇；同时，ES2在50%一氧化碳（0.45 h^-1）及200 mM甲酸（0.34 h^-1）条件下展现出优异的生长速率，该速率可与此前报道的其他产乙酸菌的生长速率相媲美，甚至更优。本研究报道了新型产乙酸ES菌株，并阐明了其遗传与生理特性，这些特性可应用于基于C1化合物的生物制造领域。