Abstract:
Nitenpyram (neonicotinoid insecticide) is commonly used for crop protection from pests. Currently, due to its widespread use, the nitenpyram accumulation in the environment is anticipated to be high. Hence, the removal of nitenpyram residue from the environment is essential. However, the biodegradation of nitenpyram by endophytes is still unreported. Therefore, we aimed to isolate and identify a bacterial strain capable of degrading nitenpyram. We isolated approximately 300 endophytic strains from Brassica rapa var. perviridis that had been exposed to different neonicotinoid insecticides. After 14 days of incubation, a bacterial strain, NIT-2, with nitenpyram degradation capability (approximately 65%) was found. Via 16S rRNA gene sequencing, the strain was identified as Bacillus thuringiensis. In addition, metabolites, 2-[N-(6-chloro-3-pyridylmethyl)-N-ethyl]amino-2-methyliminoacetic acid, N-(6-chloro-3-pyridilmethyl)-N-ethyl-N-methylformamidine (CPMF), and N-(6-chloro-3-pyridilmethyl)-N-ethylformamide (CPF), were identified during the degradation. Moreover, CPMF and CPF were further degraded 71% and 18%, respectively by NIT-2. Thus, B. thuringiensis strain NIT-2 is the first reported endophytic bacterium capable of degrading nitenpyram.
摘要:
Nitenpyra(新烟碱类杀虫剂)通常用于保护作物免受害虫的侵害。目前,由于它的广泛使用,预计环境中的氮吡喃积累量很高。因此,从环境中去除硝啶残留物是必不可少的。然而,内生菌对烯丙啶的生物降解仍未报道。因此,我们的目的是分离和鉴定一株能够降解烯啶的细菌。我们从芸苔属植物中分离出大约300株内生菌株。暴露于不同新烟碱类杀虫剂的perviridis。经过14天的孵化,一种细菌菌株,发现NIT-2具有烯丙啶降解能力(约65%)。通过16SrRNA基因测序,该菌株被鉴定为苏云金芽孢杆菌。此外,代谢物,2-[N-(6-氯-3-吡啶基甲基)-N-乙基]氨基-2-甲基亚氨基乙酸,N-(6-氯-3-吡啶二甲基)-N-乙基-N-甲基甲脒(CPMF),和N-(6-氯-3-吡啶二甲基)-N-乙基甲酰胺(CPF),在降解过程中被发现。此外,CPMF和CPF进一步降解71%和18%,分别由NIT-2。因此,苏云金芽孢杆菌菌株NIT-2是第一个报道的能够降解烯丙啶的内生细菌。