Isolation and gene characterization of a nicotine-degradation strain Agrobacterium tumefacience SCUEC1

Abstract:

[Objective] The aim of this study was to identify bacterial species capable of degrading nicotine, and to characterize related genes. [Methods] One bacterial strain with the ability to degrade nicotine was screened from tobacco field soil by using nicotine as the sole carbon source. Using phylogenetic analysis of its 16S rRNA gene, together with physiological and biochemical characteristics, we identified this strain as Agrobacterium tumefacience SCUEC1. We determined its association of degradation rate with its growth rate, and its tolerance to nicotine. Also, the genome was sequenced using high throughput sequencing technology, and the nicotine metabolic pathway of SCUEC1 strain was analyzed by bioinformatics tools. [Results] Nicotine degradation rate of SCUEC1 reached 94.81%. The strain tolerated nicotine with the concentration from 0.50 g/L to 5.00 g/L. Its metabolic pathway of nicotine degradation appeared similar to that of Ochrobactrum sp. strain SJY1. [Conclusion] Agrobacterium tumerficience SCUEC1 degraded nicotine. These findings provide a theoretical basis for biodegradation of nicotine.