category
bioRxiv
date
Feb 11, 2026
slug
status
Published
summary
1. 首次鉴定并表征6种新型细菌脲烷酶,扩展了聚氨酯降解酶学工具箱;2. 发现u15在碱性条件下的高效催化性能(kcat/KM=51.8 s-1mM-1);3. 通过晶体学和分子动力学揭示脲烷酶活性位点构象机制;4. 建立脲烷键水解的底物结合模式理论框架。
tags
蛋白质组学
核酸蛋白工具酶
type
Post
📄 原文题目
Expanding the Enzymatic Landscape for Polyurethane Degradation of Novel Bacterial Urethanases
🔗 原文链接
💡 AI 核心解读
1. 首次鉴定并表征6种新型细菌脲烷酶,扩展了聚氨酯降解酶学工具箱;2. 发现u15在碱性条件下的高效催化性能(kcat/KM=51.8 s-1mM-1);3. 通过晶体学和分子动力学揭示脲烷酶活性位点构象机制;4. 建立脲烷键水解的底物结合模式理论框架。
📝 英文原版摘要
Polyurethanes (PURs) represent a significant challenge in plastic waste management due to their chemical resilience and limited recycling options. In this study, we report the identification and characterization of six novel bacterial urethanases, expanding the enzymatic repertoire for targeted PUR depolymerization. These enzymes demonstrated carbamate-cleaving activity optimally under alkaline conditions, maintaining stability across a pH range of 7 to 10 and varying thermal and solvent tolerances. Among the candidate enzymes, u17, u10, and u15 collectively exhibited high activity, catalytic efficiency, and thermostability, establishing a strong foundation for further optimization. Building on these results, u15 emerged as particularly notable for its catalytic efficiency on the carbamate model substrate di-urethane ethylene methylenedianiline, DUE-MDA, with a kcat/KM of 51.8 {+/-}0.1 (s-1mM-1). and this motivated its selection for detailed structural analysis. High-resolution crystallography of u15 revealed key active-site architecture, including the conserved amidase signature catalytic triad and flexible loop regions that influence substrate binding and specificity. Molecular docking and molecular dynamics simulations further elucidated substrate binding determinants of u15 during urethane bond hydrolysis. Docking of DUE-MDA revealed two distinct substrate orientations (Pose A and Pose B) differing in the positioning of the carbamate group relative to Ser177. Pose A was more stable and catalytically competent, maintaining the substrate within the oxyanion hole and sustaining optimal geometry for nucleophilic attack by Ser177. Comparable behavior was observed for the partially hydrolyzed intermediate mono-urethane ethylene methylenedianiline, MUE-MDA, indicating a co
nserved binding mode across substrates. Collectively, these findings highlight amidase signature urethanases as valuable scaffolds for advancing sustainable and scalable biocatalytic recycling of polyurethanes.
- 作者:NotionNext
- 链接:https://tangly1024.com/article/30548bd6-1f96-8119-984a-cfe718b7e3a6
- 声明:本文采用 CC BY-NC-SA 4.0 许可协议,转载请注明出处。
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