中文摘要：

从广东四会原始森林土壤中分离到一株能高效还原Fe（Ⅲ）和腐殖质（HS）的兼性厌氧菌，编号为CY01．菌株CY01细胞壁革兰氏染色为阴性，细胞为杆状，大小为（1．2—1．5）μm×（0．3-0．4）μm，没有鞭毛，没有运动性，在有氧条件下氧化酶和接触酶均呈阳性反应，最适生长温度为25-30℃，最适生长pH为6．5—7．0．16SrDNA基因序列分析结果表明：菌株CY01与其亲缘关系最近的属为Comamonas（丛毛单胞菌属），该属内和CY01亲缘关系最近的种Comamonas Koreensis（韩国丛毛单胞菌）的16SrDNA序列相似值为98％，DNAG＋C物质的量百分含量为64．8．用BiologGN2系统鉴定的结果显示，有氧条件下，在提供的96种不同碳源中，CY01只能利用其中的38种．结合菌株CY01的形态学特征、生理生化特性和分子生物学特性，将菌株鉴定为Comamonas Koreensis．该菌所具有的Fe（Ⅲ）和HS还原特性为首次报道．

英文摘要：

A facultative anaerobic bacterium, designated CY01, was isolated from a primitive forest sample collected from Sihui, Guangdong, China. Strain CY01 is a highly emcient humic substances and Fe（Ⅲ）- reducing bacterium. It is a gram-negative, non-motile, non-flagella, rod-shaped （1.2-1.5 μm long, 0.3-0.4 μm wide）, oxidase and catalase-positive （under aerobic growth conditions） bacterium. Analysis of 16S rDNA of CY01 indicated that the isolate formed a monophyletic clade with the members of the genus Cornamonas. The closest phylogenetic relative among the valid species was Comamonas Koreensis, with 98% 16S rDNA similarity. The （G＋C） mol content of the DNA is 64.8. Tested by using the Biolog GN2 system, the strain could utilize 38 carbohydrates of 96 carbohydrates under aerobic growth condition. The isolate was identified as a strain of Cornamonas Koreensis based on its biochemical, physiological and morphological characteristics as well as the analysis of 16s rDNA sequence and the DNA G＋C content. The humic substances and Fe（Ⅲ）-reducing of Comamonas is here reported for the first time.