Seedorf Henning, Fricke W Florian, Veith Birgit, Brüggemann Holger, Liesegang Heiko, Strittmatter Axel, Miethke Marcus, Buckel Wolfgang, Hinderberger Julia, Li Fuli, Hagemeier Christoph, Thauer Rudolf K, Gottschalk Gerhard
Max Planck Institute for Terrestrial Microbiology, 35043 Marburg, Germany.
Proc Natl Acad Sci U S A. 2008 Feb 12;105(6):2128-33. doi: 10.1073/pnas.0711093105. Epub 2008 Jan 24.
Clostridium kluyveri is unique among the clostridia; it grows anaerobically on ethanol and acetate as sole energy sources. Fermentation products are butyrate, caproate, and H2. We report here the genome sequence of C. kluyveri, which revealed new insights into the metabolic capabilities of this well studied organism. A membrane-bound energy-converting NADH:ferredoxin oxidoreductase (RnfCDGEAB) and a cytoplasmic butyryl-CoA dehydrogenase complex (Bcd/EtfAB) coupling the reduction of crotonyl-CoA to butyryl-CoA with the reduction of ferredoxin represent a new energy-conserving module in anaerobes. The genes for NAD-dependent ethanol dehydrogenase and NAD(P)-dependent acetaldehyde dehydrogenase are located next to genes for microcompartment proteins, suggesting that the two enzymes, which are isolated together in a macromolecular complex, form a carboxysome-like structure. Unique for a strict anaerobe, C. kluyveri harbors three sets of genes predicted to encode for polyketide/nonribosomal peptide synthetase hybrides and one set for a nonribosomal peptide synthetase. The latter is predicted to catalyze the synthesis of a new siderophore, which is formed under iron-deficient growth conditions.
克氏梭菌在梭菌属中独具特色；它能以乙醇和乙酸盐作为唯一能源进行厌氧生长。发酵产物为丁酸盐、己酸盐和氢气。我们在此报告克氏梭菌的基因组序列，该序列揭示了对这一深入研究的生物体代谢能力的新见解。一种膜结合的能量转换型NADH：铁氧化还原蛋白氧化还原酶（RnfCDGEAB）和一种细胞质丁酰辅酶A脱氢酶复合物（Bcd/EtfAB），它们将巴豆酰辅酶A还原为丁酰辅酶A与铁氧化还原蛋白的还原相偶联，代表了厌氧菌中一种新的能量守恒模块。依赖NAD的乙醇脱氢酶和依赖NAD(P)的乙醛脱氢酶的基因位于微区室蛋白基因旁边，这表明这两种酶在一个大分子复合物中共同分离，形成一种类似羧基体的结构。作为严格厌氧菌的独特之处，克氏梭菌拥有三组预测编码聚酮/非核糖体肽合成酶杂合体的基因和一组非核糖体肽合成酶基因。后者预计催化一种新的铁载体的合成，该铁载体在缺铁生长条件下形成。
