弗氏柠檬酸细菌TNT降解酶及其调节  

TNT-DEGRADING ENZYME OF CITROBACTER FREUNDII AND ITS REGULATION BY CARBON AND NITROGEN SOURCE

作　　者：李文忠[1] 杨彦希[1] 杨惠芳[1] 

机构地区：[1]中国科学院微生物研究所

出　　处：《微生物学报》1989年第2期117-123,共7页Acta Microbiologica Sinica

摘　　要：在弗氏柠檬酸细菌(citrobacter freundii)TNT降解酶中,同时检出需NAD(P)H的TNT还原酶和需NAD(P)^+的TNT脱氢酶。研究了酶形成的时间过程和辅酶在TNT酶促降解反应中的行为。不同种类和不同浓度的碳、氮源对酶形成的调节作用不同。当NH_4Cl和尿素浓度小于0.1 mol/L时,能促进TNT还原酶和TNT脱氢酶的产生。KNO_3严重阻遏这两种酶的形成。葡萄糖对TNT还原酶和TNT脱氢酶的形成均有促进作用。柠檬酸钠有助于TNT脱氢酶的生成,当其浓度小于0.5%,使TNT还原酶活力提高,当大于此浓度时,使该酶活力迅速下降。It was detected that both NAD(P)Hlinked reductase (TNT-Red)and NAD(P)^+-linked TNT dehydrogenase (TNT-Deh) were present in TNT-degrading enzymes of Citrobacter freundii simultaneously. The time course of formation for the enzymes and the actions of coenzymes in enzymatic reaction of TNT have been studied. The effects of varied carbon and nitrogen sources on the regulation of the enzymes were different clearly. When the concentration of NH_4Cl or urea in culture medium was more than 0.1 mol/L, the formation of both TNT reductase and TNT dehydrogenase was promoted. However, the formation of these enzymes was inhibited by KNO_3 in culture The production of both reductase and dehydrogenase was promoted by glucose. The sodium citrate was able to help the formation of the TNT dehydrogenase. The activity of the TNT reductase was increased when the concentration of sodium citrate was less than 0.5%, but when it was more than 0.5%, the activity of this enzyme was decreased rapidly.

关 键 词：柠檬酸细菌 TNT还原酶 酶调节 

分 类 号：Q939.110.6[生物学—微生物学]