Modeling suberization with peroxidase-catalyzed polymerization of hydroxycinnamic acids: Cross-coupling and dimerization reactions
Modeling suberization with peroxidase-catalyzed polymerization of hydroxycinnamic acids: Cross-coupling and dimerization reactions
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DOI：
10.1016/j.phytochem.2006.01.026
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发表时间：
2006-04-01
期刊：
影响因子：
3.8
通讯作者：
Stark, RE
中科院分区：
文献类型：
--
作者：
Arrieta-Baez, D;Stark, RE
为了阐明植物创面愈合组织中不同羟基肉桂酸（FA、CafA、CA和SA）对之间脱氢聚合的第一步，从茄片中分离出一种阴离子马铃薯过氧化物酶（EC 1.11.1.7， APP）。使用商业辣根过氧化物酶(HRP)-H2O2催化体系，在这些偶联反应中产生相同的主要产物，为纯化和结构解析提供了足够的量。使用对羟基肉桂酸亚素前体的等摩尔混合物，只有咖啡酸在单独的交叉偶联反应中与阿魏酸和辛酸偶联。对于其他体系，HRP和APP的反应如下：(1)在含有对香豆酸和阿魏酸的反应混合物中优先与阿魏酸反应；(2)在对香豆酸和辛酸的混合物中加入辛酸；(3)阿魏酸与辛酸的混合物中加入辛酸；(4)与咖啡酸在对香豆酸与咖啡酸的混合物中反应。所得产物经核磁共振和质谱分析分离鉴定，主要具有β - β - γ -内酯和β -5苯并呋喃分子框架。五种交叉偶联产物为首次描述，而从咖啡酸和辛酸交叉偶联反应中鉴定出的β - o -4脱氢二聚体是已知的植物中含量丰富的物质。这些反应性趋势导致了关于顽固性亚木香素保护植物材料的分子结构的可测试假设，补充了之前分别通过GC-MS和固态核磁共振鉴定单体成分的分析。(c) 2006 Elsevier Ltd.版权所有。
An anionic potato peroxidase (EC 1.11.1.7, APP) thought to be involved in suberization after wounding was isolated from slices of Solanum tuberosum in order to elucidate the first steps of dehydrogenative polymerization between pairs of different hydroxycinnamic acids (FA, CafA, CA and SA) present in wound-healing plant tissues. Use of a commercial horseradish peroxidase (HRP)-H2O2 catalytic system gave the identical major products in these coupling reactions, providing sufficient quantities for purification and structural elucidation. Using an equimolar mixture of pairs of hydroxycinnamic acid suberin precursors, only caffeic acid is coupled to ferulic acid and sinapic acid in separate cross-coupling reactions. For the other systems, HRP and APP reacted as follows: (1) preferentially with ferulic acid in a reaction mixture that contained p-coumaric and ferulic acids; (2) with sinapic acid in a mixture of p-coumaric and sinapic acids; (3) with sinapic acid in a mixture of ferulic and sinapic acids; (4) with caffeic acid in a reaction mixture of p-coumaric and caffeic acids. The resulting products, isolated and identified by NMR and MS analysis, had predominantly beta-beta-gamma-lactone and beta-5 benzofuran molecular frameworks. Five cross-coupling products are described for the first time, whereas the beta-O-4 dehydrodimers identified from the caffeic acid and sinapic acid cross-coupling reaction are known materials that are highly abundant in plants. These reactivity trends lead to testable hypotheses regarding the molecular architecture of intractable suberin protective plant materials, complementing prior analysis of monomeric constituents by GC-MS and polymer functional group identification from solid-state NMR, respectively. (c) 2006 Elsevier Ltd. All rights reserved.