Fluorene oxidation in vivo by Phanerochaete chrysosporium and in vitro during manganese peroxidase-dependent lipid peroxidation
Fluorene oxidation in vivo by Phanerochaete chrysosporium and in vitro during manganese peroxidase-dependent lipid peroxidation
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DOI：
10.1128/aem.62.5.1788-1792.1996
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发表时间：
1996-05-01
影响因子：
4.4
通讯作者：
Hammel, KE
中科院分区：
文献类型：
--
作者：
Bogan, BW;Lamar, RT;Hammel, KE
本文研究了芴在黄孢原毛平革菌液体培养物中的氧化反应，以及在黄孢原毛平革菌胞外酶的作用下芴的氧化反应。完整的真菌培养物通过9-芴酮将芴代谢为9-羟基芴。还观察到向更极性的产物的一些转化。氧化芴9-芴酮也获得了在体外的系统中，含有锰（II），不饱和脂肪酸，无论是粗P. chrysosporium过氧化物酶或纯化的重组锰过氧化物酶。芴在体外的氧化抑制自由基清除剂丁羟甲苯，但不是由木质素过氧化物酶抑制剂钒酸钠。锰（III）-丙二酸配合物不能氧化芴。这些结果表明，芴在体外的氧化是由P. chrysosporium manganese peroxidase介导的脂质过氧化作用的结果。芴和二苯甲烷在体外的消失速率明显快于真正的多环芳烃或荧蒽，而真正的多环芳烃或荧蒽的消失速率与电离电位有关。这一结果表明，芴的初始氧化进行的机制以外的电子提取和苄氢提取可能是氧化的路线。
The oxidation of fluorene, a polycyclic hydrocarbon which is not a substrate for fungal lignin peroxidase, was studied in liquid cultures of Phanerochaete chrysosporium and in vitro with P. chrysosporium extracellular enzymes, Intact fungal cultures metabolized fluorene to 9-hydroxyfluorene via 9-fluorenone. Some conversion to more-polar products was also observed. Oxidation of fluorene to 9-fluorenone was also obtained in vitro in a system that contained manganese(II), unsaturated fatty acid, and either crude P. chrysosporium peroxidases or purified recombinant manganese peroxidase. The oxidation of fluorene in vitro was inhibited by the free-radical scavenger butylated hydroxytoluene but not by the lignin peroxidase inhibitor NaVO3. Manganese(III)-malonic acid complexes could not oxidize fluorene. These results indicate that fluorene oxidation in vitro was a consequence of lipid peroxidation mediated by P. chrysosporium manganese peroxidase, The rates of fluorene and diphenylmethane disappearance in vitro were significantly faster than those of true polycyclic aromatic hydrocarbons or fluoranthenes, whose rates of disappearance were ionization potential dependent. This result indicates that the initial oxidation of fluorene proceeds by mechanisms other than electron abstraction and that benzylic hydrogen abstraction is probably the route for oxidation.