Lignin dehydrogenative polymerization mechanism:: a poplar cell wall peroxidase directly oxidizes polymer lignin and produces in vitro dehydrogenative polymer rich in β-O-4 linkage
Lignin dehydrogenative polymerization mechanism:: a poplar cell wall peroxidase directly oxidizes polymer lignin and produces in vitro dehydrogenative polymer rich in β-O-4 linkage
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DOI：
10.1016/s0014-5793(04)00224-8
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发表时间：
2004-03-26
期刊：
影响因子：
3.5
通讯作者：
Kondo, R
中科院分区：
文献类型：
--
作者：
Sasaki, S;Nishida, T;Kondo, R
进行了一项调查，以确定木质素分解聚合是否通过自由基介导或直接氧化过氧化物酶进行。结果表明，松柏醇自由基迅速向芥子醇转移。转移到双松脂醇较慢，然而，转移到聚合物木质醇发生非常轻微。这一结果表明，自由基介体理论不能充分解释木质素分解聚合的机理。从白杨（Populus alha L.）愈伤组织显示出对芥子醇和芥子醇二聚体、芥子树脂醇的强烈底物偏好。此外，CWPO-C能够氧化高分子量芥子醇聚合物和亚铁细胞色素c。因此，CWPO-C特性对于生产聚合物木质素是重要的。结果表明，CWPO-C可能是一种过氧化物酶同工酶，负责植物细胞壁的木质化。(C)2004年欧洲生物化学学会联合会。Elsevier B. V.出版，保留所有权利。
An investigation was performed to determine whether lignin dehydrogenative polymerization proceeds via radical mediation or direct oxidation by peroxidases. It was found that coniferyl alcohol radical transferred quickly to sinapyl alcohol. The transfer to syringaresinol was slower, however, the transfer to polymeric lignols occurred very slightly. This result suggests that the radical mediator theory does not sufficiently explain the mechanism for dehydrogenative polymerization of lignin. A cationic cell wall peroxidase (CWPO-C) from poplar (Populus alha L.) callus showed a strong substrate preference for sinapyl alcohol and the sinapyl alcohol dimer, syringaresinol. Moreover, CWPO-C was capable of oxidizing high-molecular-weight sinapyl alcohol polymers and ferrocytochrome c. Therefore, the CWPO-C characteristics are important to produce polymer lignin. The results suggest that CWPO-C may be a peroxidase isoenzyme responsible for the lignification of plant cell walls. (C) 2004 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.