• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Applied and Environmental Microbiology >A Highly Diastereoselective Oxidant Contributes to Ligninolysis by the White Rot Basidiomycete Ceriporiopsis subvermispora
【24h】

A Highly Diastereoselective Oxidant Contributes to Ligninolysis by the White Rot Basidiomycete Ceriporiopsis subvermispora

机译：白腐烂担子菌Ceriporiopsis subvermispora对木质素分解有很高的非对映选择性氧化剂。

获取原文
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

The white rot basidiomycete Ceriporiopsis subvermispora delignifies wood selectively and has potential biotechnological applications. Its ability to remove lignin before the substrate porosity has increased enough to admit enzymes suggests that small diffusible oxidants contribute to delignification. A key question is whether these unidentified oxidants attack lignin via single-electron transfer (SET), in which case they are expected to cleave its propyl side chains between Cα and Cβ and to oxidize the threo-diastereomer of its predominating β-O-4-linked structures more extensively than the corresponding erythro-diastereomer. We used two-dimensional solution-state nuclear magnetic resonance (NMR) techniques to look for changes in partially biodegraded lignin extracted from spruce wood after white rot caused by C. subvermispora. The results showed that (i) benzoic acid residues indicative of Cα—Cβ cleavage were the major identifiable truncated structures in lignin after decay and (ii) depletion of β-O-4-linked units was markedly diastereoselective with a threo preference. The less selective delignifier Phanerochaete chrysosporium also exhibited this diastereoselectivity on spruce, and a P. chrysosporium lignin peroxidase operating in conjunction with the P. chrysosporium metabolite veratryl alcohol did likewise when cleaving synthetic lignin in vitro. However, C. subvermispora was significantly more diastereoselective than P. chrysosporium or lignin peroxidase-veratryl alcohol. Our results show that the ligninolytic oxidants of C. subvermispora are collectively more diastereoselective than currently known fungal ligninolytic oxidants and suggest that SET oxidation is one of the chemical mechanisms involved.
机译：白腐烂担子菌Ceriporiopsis subvermispora选择性地使木材脱木质素并具有潜在的生物技术应用。在底物孔隙率增加到足以吸收酶之前，其去除木质素的能力表明，较小的可扩散氧化剂有助于脱木质素。一个关键问题是这些未知氧化剂是否通过单电子转移（SET）攻击木质素，在这种情况下，它们有望在C α和C βα -C β裂解的苯甲酸残基是木质素衰变后可识别的主要截短结构，以及（ii）β- O-4-连接的单元明显具有非对映选择性，具有苏氨酸偏好。选择性较低的脱木素植物Phanerochaete chrysosporium在云杉上也表现出这种非对映选择性，并且在体外裂解合成木质素时，P。chrysosporium木质素过氧化物酶与P. chrysosporium代谢产物藜芦醇共同作用。但是，C。subvermispora比Ch.sporsporium或木质素过氧化物酶-藜芦醇具有更高的非对映选择性。我们的结果表明，比目前已知的真菌木质素分解氧化剂，C。subvermispora的木质素分解氧化剂总体上具有更高的非对映选择性，并且表明SET氧化是其中涉及的化学机理之一。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号