摘要
本研究以赣州稀土矿区尾矿土壤微生物为研究对象,利用限制性片段长度多态性(restriction fragment length polymorphism,RFLP)技术,获得一株硫酸铵耐性菌株。通过16 S rDNA序列测定,鉴定该菌株属于短波单胞菌属(Brevundimonas sp.),命名为Brevundimonas sp.LNa,该菌株对硫酸铵的最高耐受浓度可达0.9 mol/L。进一步研究了环境因素对菌株LNa生长的影响,并表征其生理生化特性。结果表明:菌株LNa对硫酸链霉素不敏感,在低于1 mol/L硫酸铵处理,pH在6-7.5之间,菌株均能正常生长。菌株LNa能不同程度地降低培养基中氨氮和硫酸盐浓度,在0.7 mol/L硫酸铵胁迫下降解效果最好,氨氮浓度能降低约29%,硫酸盐浓度降低约36.7%;随着硫酸铵胁迫浓度的升高,菌株LNa的FDA水解酶(Fluorescein diacetate,FDA)、蛋白酶、脱氢酶和过氧化氢酶的活性都有不同程度的降低,当浓度上高到0.6 mol/L后,菌株的过氧化氢酶活性将不再发生变化。LNa菌株对氨氮和硫酸盐的降解能力,可能与细菌FDA水解酶和蛋白酶活性的分泌有关。
The resistant strains were isolated from the soils of rare earth mines in Ganzhou by PCR-RFLP technology.Anammonium sulfate resistant strain named as Brevundimonas sp.LNa was obtained.The maximum tolerance concentration of the strain to ammonium sulfate was 0.9 mol/L.The effects of environmental factors on the growth of strain LNa were further studied,and its physiological and biochemical characteristics were characterized.The results showed that strain LNa was not sensitive to streptomycin sulfate and could grow normally when the concentration of ammonium sulfate was lower than 1 mol/L,and pH was between 6-7.5.The concentration of ammonia nitrogen and sulfate in the culture medium was decreased by inoculating LNa strain,and the maximum degradation rates of ammonia nitrogen and sulfate were 29%and 36.7%respectively when the treated concentration of ammonium sulfate is 0.7 mol/L.With the increase of ammonium sulfate stress concentration,the activities of FDA hydrolase,protease,dehydrogenase and catalase of strain LNa were decreased in varying degrees.When the concentration was up to 0.6 mol/L,the catalase activity of strain LNa would not change.Therefore,the degradation ability of strain LNa to ammonia nitrogen and sulfate may be related to the secretion of FDA hydrolase and protease activity.
作者
龙婉婉
王金凤
廖永辉
贺根和
LONG Wan-wan;WANG Jin-feng;LIAOYong-hui;HE Gen-he(School of Life Sciences,Jinggangshan University,Ji’an Jiangxi 343009,China;Key Laboratory of Agricultural Environmental Pollution Prevention and Control in Red Soil Hilly Region of Jiangxi Province,Ji’an,Jiangxi 343009,China)
出处
《井冈山大学学报（自然科学版）》
2020年第6期33-39,共7页
Journal of Jinggangshan University (Natural Science)
基金
国家重点研发计划子课题项目(2019YFC180510303)
江西省自然科学基金面上项目(20181BAB203025)。
关键词
硫酸铵
耐性菌
分离鉴定
降解
酶活性
ammonium sulphate
resistant bacterial strain
isolation and identification
degradation
enzyme activity
