Catabolism of Phloroglucinol by the Rumen Anaerobe Coprococcus
Catabolism of Phloroglucinol by the Rumen Anaerobe Coprococcus
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DOI：
10.1128/aem.42.6.1010-1017.1981
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发表时间：
1981-12
影响因子：
4.4
通讯作者：
T. Patel;K. G. Jure;G. Jones
中科院分区：
文献类型：
--
作者：
T. Patel;K. G. Jure;G. Jones
发现瘤胃分离物粪球菌属Pe 15携带间苯三酚还原酶，其催化间苯三酚分解的初始步骤。这种生物在缺氧条件下生长时，以间苯三酚为唯一的碳源和能量来源。在间苯三酚或其他碳源上生长的细胞中检测到有限量的间苯三酚存在的诱导水平的酶。虽然这种生物是严格的厌氧生物，但厌氧生长细胞中的酶对空气不敏感。部分纯化的酶需要还原的烟酰胺腺嘌呤二核苷酸磷酸作为电子供体，并且对间苯三酚具有特异性。然而，部分酶活性（1,4至17%）也检测到在2-甲基-1，4-萘醌的存在下，但不是在存在的几个其他酚类化合物。该酶对间苯三酚的亲和力高于对还原型烟酰胺腺嘌呤二核苷酸磷酸的亲和力，Km值分别为3.0 × 10−5 M和29.0 × 10−5 M。最大酶活性的最适pH为7.4，天然蛋白质的分子量约为130，000，通过Sephadex凝胶过滤技术测定。
A rumen isolate, Coprococcus, sp. Pe15, was found to carry phloroglucinol reductase, which catalyzed the initial step in the breakdown of phloroglucinol. The organism uses phloroglucinol as the sole source of carbon and energy when grown in the absence of oxygen. Induced levels of enzyme were detected in cells grown either on phloroglucinol or on other carbon sources in the presence of limiting quantities of phloroglucinol. Although the organism is a strict anaerobe, the enzyme from anaerobically grown cells was insensitive to air. The partially purified enzyme required reduced nicotinamide adenine dinucleotide phosphate as an electron donor and was specific for phloroglucinol. However, partial enzyme activity (14 to 17%) was also detected in the presence of 2-methyl-1,4-naphthoquinone but not in the presence of several other phenolic compounds. The enzyme exhibited a higher affinity for phloroglucinol than for reduced nicotinamide adenine dinucleotide phosphate, with Km values of 3.0 × 10−5 M and 29.0 × 10−5 M, respectively. The optimum pH for maximal enzyme activity was 7.4, and the molecular weight of the native protein was about 130,000, as determined by the Sephadex gel filtration technique.