摘要
从长期使用拟除虫菊酯类农药的土壤中筛选分离到1株甲氰菊酯降解菌CZ-1,对其降解特性和生物学特性进行了研究。经生理生化试验和16 S rDNA序列同源性分析,初步将菌株CZ-1鉴定为红假单胞菌属(Rhodopseudomonas sp.)。GC对菌株CZ-1降解特性的研究表明,菌株CZ-1以共代谢方式降解甲氰菊酯。最佳降解条件为:pH=7.5,35℃。菌株CZ-1在最佳降解条件下,7 d对200 mg/L的甲氰菊酯降解率达75.36%。菌株CZ-1对植物促生的相关特性表明,培养24 h,菌株CZ-1能够产生吲哚乙酸(IAA)(1.86±0.12)mg/L,ACC脱氨酶活性为(0.39±0.01)U/mg,能显著增加玉米的根长。
A photosynthetic bacterial strain CZ-1, which is capable to efficiently degrade synthetic pyrethroid fenpropathrin, was isolated from contaminated soil by enrichment media. Strain CZ-1 showed the highest biodegrading potential of synthetic pyrethroid fenpropathrin. It was selected for further biodegradation characterization and biological studies. Strain CZ-1 was tentatively identified as a member of genus Rhodopseudomonas based on its biochemical tests, homology and phylogenetic analysis of 16S rDNA sequence （Genbank accession number GU477345）. The results of degrading characteristics study showed that strain CZ-1 could not merely use synthetic pyrethroid fenpropathrin as its carbon source. When other carbon sources （Glucose and yeast extracts） were added, strain CZ-1 exhibited rapid degradation of synthetic pyrethroid fenpropathrin, showing that strain CZ-1 was able to degrade synthetic pyrethroid fenpropathrin in a co-metabolic pathway. The characteristics of strain CZ-1 for degrading synthetic pyrethroid fenpropathrin were performed under different culture conditions. The results showed that temperature of 35 ℃ and pH=7.5 were the optimal degrading conditions, and strain CZ-1 could degrade 75.36% of synthetic pyrethroid fenpropathrin with concentration of 200 mg/L within 7 d in the optimal conditions. The results of biological characterizations showed that strain CZ-1 exhibited high IAA （indole-3-acetic acid） productivity, i.e. it could produce IAA at （1.86±0.12） mg/L in PSB （photosynthetic bacterium） media in 24 h. In addition, strain CZ-1 also displayed significant bioactivity of ACC（1-aminocyclopropane-1-carboxylate） deaminase, its ACC deaminase bioactivity was （0.39±0.01） U/mg in PSB media in 24 h. The potential of promoting crop growth was performed by measuring the root length of maize （Zea mays L.）, and the result showed that strain CZ-1 promoted significantly the growth of maize root length at the beginning of 48 h. The result also indicated that the sterilized brot
出处
《安全与环境学报》
CAS
CSCD
北大核心
2011年第2期69-72,共4页
Journal of Safety and Environment
基金
国家863计划项目(2006AA10Z401)
湖南省农村科技计划重点项目(2008NK2009)
关键词
环境工程学
生物降解
光合细菌
甲氰菊酯
生物学特性
environmental engineering
biodegradation
photosynthetic bacterium
fenpropathrin
plant-growth promoting
