一株铁还原细菌ZLJ24的筛选、鉴定及其固氮特性  

Isolation,identification and nitrogen-fixing characteristics of an iron-reducing bacterium ZLJ24

作　　者：赵李佳 邱子健 高南 李林梅 申卫收 ZHAO Li-jia;QIU Zi-jian;GAO Nan;LI Lin-mei;SHEN Wei-shou(School of Environmental Science and Engineering,Nanjing University of Information Science and Technology/Jiangsu Provincial Key Laboratory of Atmospheric Environment Monitoring and Pollution Control/Jiangsu Provincial Collaborative Innovation Center of Atmospheric Environment and Equipment Technology,Nanjing Jiangsu 210044;College of Biological and Pharmaceutical Engineering/NationalResearch Center for Biochemical Engineering Technology,Nanjing University of Technology,Nanjing Jiangsu 211816)

机构地区：[1]南京信息工程大学环境科学与工程学院/江苏省大气环境监测与污染控制高技术研究重点实验室/江苏省大气环境与装备技术协同创新中心,江苏南京210044 [2]南京工业大学生物与制药工程学院/国家生化工程技术研究中心,江苏南京211816

出　　处：《中国土壤与肥料》2025年第1期241-249,共9页Soil and Fertilizer Sciences in China

基　　金：国家自然科学基金(42377311);江苏省农业科技自主创新资金项目[CX(21)3183]。

摘　　要：筛选获得具有Fe3+还原活性及固氮能力的细菌,用于构建基于新型生物固氮体系的绿色低氮水稻生产。通过无氮培养基、柠檬酸铁培养基筛选和LB培养基纯化,从水稻土中分离筛选得到一株细菌ZLJ24;通过形态特征观察、16S rRNA基因序列测定、nifH基因扩增,对菌株进行分类鉴定。结果显示,菌株ZLJ24为肺炎克雷伯菌(Klebsiella pneumoniae),属革兰氏阴性杆菌,含nifH基因。在厌氧条件下培养72 h,其Fe^(3+)还原效率为90.24%。在无氮培养基中培养24 h,其固氮酶活性为89.28 nmol-C_(2)H_(4)/(min·mg蛋白质)。在添加不同碳源的处理中,ZLJ24在添加低浓度葡萄糖后固氮酶活性最高,为19460.76 nmol-C_(2)H_(4)/(h·mg蛋白质)。本研究表明,菌株ZLJ24具有良好的铁还原能力和固氮能力,添加葡萄糖对菌株ZLJ24固氮活性具有明显地促进作用。本研究将为构建基于新型生物固氮体系的绿色低氮水稻生产提供新思路。This study aimed to isolate and characterize a novel bacterium with iron-reducing and nitrogen-fixing capabilities from rice paddy soil,with potential applications in green,low-nitrogen rice production.A strain ZLJ24 was isolated from paddy soil through a series of screening processes,including cultivation on nitrogen-free medium,ferric citrate medium,LB agar medium.Morphological observations,16S rRNA gene sequencing,and nifH gene amplification were employed for identification,revealing strain ZLJ24 to be a member of the genus Klebsiella pneumoniae,a Gram-negative bacillus,and it was positive for the nifH gene,which is associated with biological nitrogen fixation.The efficiency of iron reduction by strain ZLJ24 under anaerobic conditions was found to be 90.24% after 72 hours of cultivation.Its nitrogenase activity in a nitrogen-free medium was 89.28 nmol-C_(2)H_(4)/(min·mg protein).Intriguingly,the addition of low concentrations of glucose significantly enhanced the nitrogenase activity,reaching a maximum of 19460.76 nmol-C_(2)H_(4)/(h·mg protein).These results demonstrated that strain ZLJ24 could possesse both robust iron reduction and nitrogen fixation capabilities,with glucose acting as a potent stimulant for its nitrogenase activity.This study contributed a promising strategy for developing a green,low-nitrogen rice production system based on biological nitrogen fixation,and offered a novel approach to sustainable agriculture.

关 键 词：肺炎克雷伯菌 铁还原 生物固氮 水稻土 固氮酶活性 

分 类 号：S51[农业科学—作物学]