Taxa-4,11-diene is made by the taxa-4,11-diene synthase (TxS) from Taxus brevifolia. The unique reactivity of the taxane system is characterised by long distance hydrogen migrations in the biosynthesis. This study demonstrates that selective long range hydrogen migrations also play a role in the high energy process of the EI-MS fragmentation of taxa-4,11-diene. A TxS enzyme variant was generated that produces cyclophomactene, a compound that is formed through a concerted process involving a long range proton shift and a ring closure that can also be described as the addition of a methylcarbinyl cation to an olefin. Based on a previous computational study the cyclisation mechanism towards taxa-4,11-diene was suggested to involve two long distance proton migrations instead of one direct transfer. A substrate analog with a shifted double bond was converted with TxS to obtain experimental evidence for this proposal.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1002/anie.202422788 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Enhancing the affinity of Pb(II) to the metastable ferrihydrite with the presence of gallic acid and anoxia condition.
J Environ Manage
January 2025
School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China. Electronic address:
Naturally widespread ferrihydrite is unstable and often coexists with complex ions, such as the heavy metal ion Pb(II). Ferrihydrite could fix Pb(II) by precipitation and hydroxyl adsorption, but release Pb(II) with mineral aging. Gallic acid plays an important role in influencing the geochemical behavior of ferrihydrite-Pb, and anoxia is one of the factors influencing the transformation of mineral.
View Article and Find Full Text PDFOn the Role of Hydrogen Migrations in the Taxadiene System.
Angew Chem Int Ed Engl
January 2025
University of Bonn: Rheinische Friedrich-Wilhelms-Universitat Bonn, Kekulé Institute for Organic Chemistry and Biochemistry, Gerhard-Domagk-Straße 1, 53121, Bonn, GERMANY.
Taxa-4,11-diene is made by the taxa-4,11-diene synthase (TxS) from Taxus brevifolia. The unique reactivity of the taxane system is characterised by long distance hydrogen migrations in the biosynthesis. This study demonstrates that selective long range hydrogen migrations also play a role in the high energy process of the EI-MS fragmentation of taxa-4,11-diene.
View Article and Find Full Text PDFAn Importin Protein SlIMPA3 Interacts with SlLCD1 and Regulates Tomato Fruit Ripening.
J Agric Food Chem
January 2025
School of Food and Biological Engineering, Hefei University of Technology, Hefei 230009, China.
A nuclear-localized cysteine desulfhydrase, LCD1, plays a crucial role in mediating endogenous hydrogen sulfide production in tomatoes. However, the mechanism underlying the nuclear localization of SlLCD1 is not yet fully understood. In this study, it was found that SlLCD1 specifically interacted with nuclear import receptor importin α3 (SlIMPA3).
View Article and Find Full Text PDFEnhancing photocatalytic hydrogen evolution of carbon nitride through high-valent cobalt active sites in cobalt sulfide co-catalyst.
J Colloid Interface Sci
December 2024
School of Materials Science & Engineering, School of the Environment and Safety Engineering, Jiangsu University, Zhenjiang 212013, PR China; Zotye Automobile Co., Ltd, Jinhua 321399, PR China. Electronic address:
Article Synopsis
- Photocatalytic hydrogen production using solar energy is an effective solution for energy and environmental issues, but inefficiencies arise from the rapid recombination of charges in semiconductor catalysts.
- Researchers used a co-catalyst loading strategy, specifically incorporating cobalt sulfide (CoS) onto bulk carbon nitride (BCN), to enhance photocatalytic performance for hydrogen production.
- The optimal CoS-BCN composite (with 15% CoS) showed a performance improvement of 156 times compared to BCN alone, as CoS nanoparticles facilitate electron transfer and reduce charge recombination, enhancing hydrogen evolution efficiency.
Cellulose nanofibril enhanced ionic conductive hydrogels with high stretchability, high toughness and self-adhesive ability for flexible strain sensors.
Int J Biol Macromol
December 2024
State Key Laboratory of Metastable Materials Science and Technology, Hebei Key Laboratory of Applied Chemistry, Hebei Key Laboratory of Nanobiotechnology, Hebei Key Laboratory of Heavy Metal Deep-Remediation in Water and Resource Reuse, Yanshan University, Qinhuangdao 066004, China. Electronic address:
Preparation of ion-conductive hydrogels with excellent mechanics, good conductivity and adhesiveness is promising for flexible sensors, but remains a challenge. Here, we prepare a self-adhesive and ion-conductive hydrogel by introducing cellulose nanofibers (CNF) and ZnSO into a covalently-crosslinked poly (acrylamide-co-2-acrylamide-2-methyl propane sulfonic acid) (P(AM-co-AMPS)) network. Owing to the hydrogen bonding and metal coordination interactions among P(AM-co-AMPS) chains, CNF, and Zn, the resulting P(AM-co-AMPS)/CNF/ZnSO hydrogel exhibits high stretchability (1092 %), high toughness (244 kJ m), and skin-like elasticity (3.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!