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

Abstract:

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.