REDUCTION OF NITROAROMATIC COMPOUNDS BY ANAEROBIC-BACTERIA ISOLATED FROM THE HUMAN GASTROINTESTINAL-TRACT
REDUCTION OF NITROAROMATIC COMPOUNDS BY ANAEROBIC-BACTERIA ISOLATED FROM THE HUMAN GASTROINTESTINAL-TRACT
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DOI：
10.1128/aem.57.4.962-968.1991
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发表时间：
1991-04-01
影响因子：
4.4
通讯作者：
CERNIGLIA, CE
中科院分区：
文献类型：
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作者：
RAFII, F;FRANKLIN, W;CERNIGLIA, CE
通过在含有 1-硝基芘的脑心浸液琼脂平板上培养人类肠道微生物菌群，筛选其减少硝基芳香族化合物的能力。 通过菌落周围清晰区域的出现检测到代谢 1-硝基芘的细菌被鉴定为软梭菌、副腐败梭菌、梭菌形梭菌、另一种梭菌属和真杆菌属。 薄层色谱、高压液相色谱和生化测试表明，这些细菌从硝基芳香族化合物中产生芳香胺。 将其中三种细菌与 1-硝基芘、1,3-二硝基芘和 1,6-二硝基芘一起孵育，可灭活与这些化合物相关的直接致突变性。 甲萘醌和邻碘代苯甲酸抑制所有分离物中的硝基还原酶活性，表明酶的活性位点涉及巯基。 硝基还原酶活性的最适pH为8.0。 仅梭菌属 sp。需要添加黄素腺嘌呤二核苷酸来发挥硝基还原酶活性。 硝基还原酶是组成型的和细胞外的。 开发了一种用于检测厌氧天然聚丙烯酰胺凝胶上硝基还原酶的活性染色剂。 该活性染色仅显示每种细菌中存在一种同工酶，但显示来自不同细菌的硝基还原酶具有不同的电泳迁移率。
Human intestinal microbial flora were screened for their abilities to reduce nitroaromatic compounds by growing them on brain heart infusion agar plates containing 1-nitropyrene. Bacteria metabolizing 1-nitropyrene, detected by the appearance of clear zones around the colonies, were identified as Clostridium leptum, Clostridium paraputrificum, Clostridium clostridiiforme, another Clostridium sp., and a Eubacterium sp. These bacteria produced aromatic amines from nitroaromatic compounds, as shown by thin-layer chromatography, high-pressure liquid chromatography, and biochemical tests. Incubation of three of these bacteria with 1-nitropyrene, 1,3-dinitropyrene, and 1,6-dinitropyrene inactivated the direct-acting mutagenicity associated with these compounds. Menadione and o-iodosobenzoic acid inhibited nitroreductase activity in all of the isolates, indicating the involvement of sulfhydryl groups in the active site of the enzyme. The optimum pH for nitroreductase activity was 8.0. Only the Clostridium sp. required added flavin adenine dinucleotide for nitroreductase activity. The nitroreductases were constitutive and extracellular. An activity stain for the detection of nitroreductase on anaerobic native polyacrylamide gels was developed. This activity stain revealed only one isozyme in each bacterium but showed that the nitroreductases from different bacteria had distinct electrophoretic mobilities.