具有ACC脱氨酶活性的杜仲内生细菌的分离鉴定及其抗菌活性

采用富集筛选法从杜仲根中分离到5株具有ACC脱氨酶活性的内生细菌, 利用纸片法测定它们的抑菌活性, 通过形态特征、生理生化试验和16S rRNA序列分析对分离菌株进行鉴定。结果显示, 5株杜仲内生细菌均具有较高的ACC脱氨酶活性, 其中4株菌对大肠杆菌CGMCC1.1103和枯草芽孢杆菌CGMCC1.769均有较好的抑菌活性, 通过生理生化试验和16S rRNA序列分析, 将菌株JDM-2、JDM-8、JDM-11、JDM-14和JDM-19分别鉴定为Pseudomonas koreensis、肺炎克雷伯氏菌(Klebsiella pneumoniae)、路德维希肠杆菌(Enterobacter ludwigii)、变栖克雷伯氏菌(Klebsiella variicola)和阿氏肠杆菌(Enterobacter asburiae)。

Isolation and antibacterial activity of ACC deaminase-containing endophytic bacteria from Eucommia ulmoides Oliver

Five endophytic bacteria containing ACC-deaminase were isolated from the roots of Eucommia ulmoides Oliver based on their ability to utilize ACC as a nitrogen source, and their antibacterial activities were determined by using the agar disc diffusion test. Identification of these isolates was determined by their morphological, physiological-biochemical properties and phylogenetic analysis based on 16S rRNA gene sequences. The ACC deaminase activity assay demonstrated that the five endophytic bacterial isolates expressed the ACC deaminase activity, and four isolates of them displayed antibacterial activity against Escherichia coli CGMCC1.1103 and Bacillus subtilis CGMCC1.769, respectively. Five ACC deaminase-containing endophytic bacteria isolates named as JDM-2, JDM-8, JDM-11, JDM-14 and JDM-19 were identified as Pseudomonas koreensis, Klebsiella pneumoniae, Enterobacter ludwigii, Klebsiella variicola and Enterobacter asburiae, respectively.