CAJ | 학술논문

通过摇瓶实验研究了克雷伯氏菌(S1)和伯克霍尔德氏菌(S2)复合菌群(简称S)降解三硝基甲苯(TNT)的特性和机理.结果表明,在外加碳源和氮源时,100mg/LTNT在16h内可被菌群S完全去除.只外加碳源时,TNT的最高去除率为80%;只加入氮源时,仍可除去12%的TNT.在S1催化体系中检测到较高活性硝基还原酶的存在,该酶催化TNT转化为缩合中间产物二硝基双偶氮甲苯,其分子量为326.但是只有S1和S2共存才能产生高活性的甲苯双加氧酶和邻苯二酚2,3-双加氧酶.两类酶共同催化中间产物的开环分解.伴随着二硝基双偶氮甲苯的开环分解,硝基脱落生成NO_2~-,后者进一步氧化生成NO_3~-.通过S1和S2的协同作用,实现了TNT的好氧开环和硝基脱落,该结果表明在TNT生物催化降解中复合菌群比单一菌株更具优势和潜力.
통과요병실험연구료극뢰백씨균(S1)화백극곽이덕씨균(S2)복합균군(간칭S)강해삼초기갑분(TNT)적특성화궤리.결과표명,재외가탄원화담원시,100mg/LTNT재16h내가피균군S완전거제.지외가탄원시,TNT적최고거제솔위80%;지가입담원시,잉가제거12%적TNT.재S1최화체계중검측도교고활성초기환원매적존재,해매최화TNT전화위축합중간산물이초기쌍우담갑분,기분자량위326.단시지유S1화S2공존재능산생고활성적갑분쌍가양매화린분이분2,3-쌍가양매.량류매공동최화중간산물적개배분해.반수착이초기쌍우담갑분적개배분해,초기탈락생성NO_2~-,후자진일보양화생성NO_3~-.통과S1화S2적협동작용,실현료TNT적호양개배화초기탈락,해결과표명재TNT생물최화강해중복합균군비단일균주경구우세화잠력.
The biodegradation characteristic and mechanism of trinitrotoluene(TNT)by a bacterial consoaium S consisted of Klebsiella sp.S1 and Burkholderia sp.S2 were investigated bv shaking.flask culture.The results show that the consortium S can completely biodegrade 0.1 g/L TNT in solution in the presence of both extemal carbon and nitrogen sources,whereas the biodegradation efficiency of TNT reaches 80%and 12%,respectively,with external carbon source only and nitrogen source only.Highly active nitroreductase Was detected in the S1 catalyst system.This enzyme transformed TNT into a condensation product,diazodinitrotoluene,which was further degraded through ring cleavage catalyzed by the combined action of highly active toluene dioxygenase and catechol dioxygenase produced in the case of coexistence of S1 and S2.Nitro groups in TNT were released during the ring cleavage of diazodinitrotoluene.resulting in the formation of NO_2~-,which was further oxidized into NO_3~-.This bacterial consortium has greater potentials in biodegradation of TNT than the single bacterium.