一株同步硝化-反硝化菌的絮凝特性  

Aggregation characteristics of a nitrifying-denitrifying bacterium

作　　者：李丹 梁锡宏 李政威 金垚 吴重德[1] 周荣清[1] LI Dan;LIANG Xihong;LI Zhengwei;JIN Yao;WU Chongde;ZHOU Rongqing(Key Laboratory of Leather Chemistry and Engineering of the Ministry of Education,College of Light Industry,Textile&;Food Engineering,Sichuan University,Chengdu 610065,China)

机构地区：[1]四川大学轻纺与食品学院皮革化学与工程教育部重点实验室,四川成都610065

出　　处：《生物加工过程》2019年第1期104-109,共6页Chinese Journal of Bioprocess Engineering

基　　金：国家重点研发计划(2017YFB0308500);四川大学跨学科专业--贯通式人才培养建设平台项目(SCUKG017);大学生创新创业计划(C2018101384)

摘　　要：研究了1株克雷伯氏菌(Klebsiella sp. TN-10)的硝化反硝化性能,结果表明,该菌能高效降解铵态氮(NH_4^+)、硝态氮(NO-3)和亚硝态氮(NO_2^-)。在初始NH_4^+质量浓度为77. 93 mg/L的培养基中,Klebsiella sp. TN-10能够在20 h内降解93. 3%的NH_4^+,其硝化速率为3. 02 mg/(L·h);在初始NO-3和NO_2^-质量浓度分别为64. 03和87. 68 mg/L的培养基中,TN-10能够在40 h内降解95. 44%的NO-3和93. 44%的NO_2^-。测定了该菌株在不同生长周期的自聚集能力和聚集动力学,结果表明,该菌在衰亡期呈现更好的自聚集性。对菌株TN-10的胞外聚合物(EPS)组成进行了研究,结果表明,其蛋白质含量为23. 84 mg(以每克干细胞质量计),多糖含量为18. 64 mg(以每克干细胞质量计)。红外图谱表明,EPS主要成分为蛋白质和多糖。测定EPS的圆二图谱,对EPS中蛋白质二级结构进行深入分析,结果表明α-螺旋占主要比例,为55. 08%。本研究对深入认识TN-10的特点具有重要意义,也可为硝化反硝化菌胞外聚合物研究提供重要参考。The nitrifying-denitrifying characteristics of Klebsiella sp.TN-10 were investigated,and the results showed that the bacterium could utilize NH4^+,NO3^-and NO2^-efficiently.When the initial concentration of NH 4+was 77.93 mg/L in the culture,Klebsiella sp.TN-10 could degrade 93.3%ammonia nitrogen with nitrification rate 3.02 mg/(L·h).While the initial concentration of NO3^-and NO2^-was 64.03 mg/L and 87.68 mg/L,respectively,the strain could degrade 95.44%NO3^-and 93.44%NO2^-.The auto-aggregation ability and aggregation kinetics under different growth cycle were measured,and strain TN-10 exhibited higher auto-aggregation property in decline phase.The composition of extracellular polymeric substances(EPS)from TN-10 was measured,and the content of protein and polysaccharide were 23.84 mg and 18.64 mg per 1 g dry cells,respectively.The infrared spectra of EPS showed that their main components of EPS were protein and polysaccharide.The circular dichroism spectrum of EPS was measured to analyze their secondary structure of EPS andα-helices had the highest proportion accounting for 55.08%.This study could help understanding the characteristics of strain TN-10 and provide reference to study nitrifying-denitrifying bacteria.

关 键 词：同步硝化反硝化菌 自聚集 胞外聚合物 絮凝 脱氮细菌 

分 类 号：X172[环境科学与工程—环境科学]