磺胺二甲嘧啶废水处理系统中Exiguobacterium sp.H-1的分离及其环境适应特性
Isolation of Exiguobacterium sp.H-1 from the sulfamethazine wastewater treatment system and its environmental adaptation characteristics
陈田 1王壮 1芦梦瑶 1陈研 1周佳 1屈建航 1潘婧诗 2罗宇1
作者信息
- 1. 河南工业大学生物工程学院
- 2. 河南工业大学国际教育学院
- 折叠
摘要
磺胺二甲嘧啶(SMZ)是一种难降解的广谱抗生素,其广泛存在已对水环境构成严重的威胁.微生物是环境中抗生素降解转化的主要驱动者,但高效降解SMZ的微生物资源匮乏.以SMZ废水处理系统的活性污泥为原料,采用纯培养技术从中分离筛选出一株 SMZ降解菌 H-1.经形态学观察、生理生化特征、16S rRNA基因序列分析,H-1 归属于微小杆菌属(Exiguobacterium sp.).通过单因素试验研究初始SMZ浓度、接种量、pH和温度对菌株H-1 降解SMZ效果的影响.结果表明,接种量、pH和温度对该菌株降解SMZ的影响较大.进一步采用响应面法优化菌株Exiguobacterium sp.H-1 降解SMZ的最佳条件,得出pH为 7.21,温度为 28.86℃,接种量为 4.40%时,其对 5 mg/L SMZ降解率为 10.54%.本研究发现微小杆菌Exiguobacterium sp.H-1 具有降解SMZ的能力,其降解SMZ的独特之处是能够将SMZ脱去SO2,生成嘧啶环和苯胺环,经过耦合生成N-(4,6-二甲基嘧啶-2 基)-1,4-二苯胺,然后进行脱氨反应,生成 2-苯-4,6-二甲基嘧啶,随后去甲基化生成产物 6(2-苯基-1,2-二氢嘧啶,m/z为 159.97).此外,菌株H-1 在 0～10%NaCl的广泛范围内也表现出很强的耐盐性,能够为SMZ污染水体的生物修复提供耐盐能力强的微生物菌株资源.
Abstract
Sulfamethazine(SMZ)is a broad-spectrum antibiotic that is difficult to degrade,and its widespread presence poses a serious threat to the aquatic environment.Microorganisms are the main drivers of antibiotic degradation and transformation in the environment,but microbial resources for efficient degradation of SMZ are limited.Therefore,a strain of SMZ-degrading bacteria H-1 was isolated and screened from the activated sludge of SMZ wastewater treatment system by the pure culture technique.The strain H-1 was classified as the genus of Exiguobacterium sp.based on its morphological observation,physiological and biochemical characteristics,and 16S rRNA gene sequence analysis.The effects of initial SMZ concentration,inoculum,pH and temperature on the degradation of SMZ by strain H-1 were investigated by a single-factor test,and it indicated that the inoculum,pH and temperature affected greater on the degradation of SMZ by strain H-1.The optimal conditions for the degradation of SMZ by strain Exiguobacterium sp.H-1 were further optimized by response surface methodology:pH 7.21,temperature 28.86℃,inoculum level 4.40%,and its removal efficiency of 5 mg/L SMZ was 10.54%.It is found for the first time that Exiguobacterium sp.H-1 has the ability to degrade SMZ,and it is able to remove SMZ from SO2 first to produce pyrimidine and aniline rings,which are coupled to generate N-4,6-dimethylpyrimidin-2-yl)-1,4-diphenylamine,and then the deamination reaction proceeds to produce 2-phenyl-4,6-dimethylpyrimidine,which is subsequently demethylated to produce product 6(m/z=159.97).In addition,strain H-1 also shows a strong salt tolerance within a wide range of 0-10%NaCl,providing a resource of salt-tolerant microbial strains for the bioremediation of SMZ-polluted waters.
关键词
磺胺二甲嘧啶/Exiguobacterium/生物降解/环境适应性/生物修复Key words
sulfamethazine/Exiguobacterium/biodegradation/environmental adaptability/bioremediation引用本文复制引用
基金项目
国家自然科学基金(42107139)
河南工业大学高层次人才科研启动基金(2019BS046)
河南工业大学青年骨干教师培育计划(21421206)
出版年
2024
NETL
NSTL
维普
万方数据