Because of nicotine's toxicity and the high levels found in tobacco and in the waste from tobacco processing, there is a great deal of interest in identifying bacteria capable of degrading it. A number of microbial pathways have been identified for nicotine degradation. The first and best-understood is the pyridine pathway, best characterized for Arthrobacter nicotinovorans, in which the first reaction is hydroxylation of the pyridine ring. The pyrrolidine pathway, which begins with oxidation of a carbon-nitrogen bond in the pyrrolidine ring, was subsequently characterized in a number of pseudomonads. Most recently, a hybrid pathway has been described, which incorporates the early steps in the pyridine pathway and ends with steps in the pyrrolidine pathway. This review summarizes the present status of our understanding of these pathways, focusing on what is known about the individual enzymes involved.

中文翻译：

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微生物尼古丁代谢的酶。

由于尼古丁的毒性以及烟草和烟草加工废料中高含量的尼古丁，人们对鉴定能够降解尼古丁的细菌有极大的兴趣。已经确定了许多尼古丁降解的微生物途径。第一个也是最容易理解的是吡啶途径，对烟碱节杆菌有最好的表征，其中第一个反应是吡啶环的羟基化。吡咯烷途径始于吡咯烷环中碳-氮键的氧化，随后被表征为许多假单核糖。最近，已经描述了一种混合途径，其掺入了吡啶途径中的早期步骤，并终止于吡咯烷途径中的步骤。这篇评论总结了我们对这些途径的理解的现状，