دورية أكاديمية
Rapid reaction studies on the chemistry of flavin oxidation in urocanate reductase.
العنوان: | Rapid reaction studies on the chemistry of flavin oxidation in urocanate reductase. |
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المؤلفون: | Delavari N; Department of Chemistry, Western Michigan University, Kalamazoo, Michigan, USA., Zhang Z; Department of Chemistry, Western Michigan University, Kalamazoo, Michigan, USA., Stull F; Department of Chemistry, Western Michigan University, Kalamazoo, Michigan, USA. Electronic address: frederick.stull@wmich.edu. |
المصدر: | The Journal of biological chemistry [J Biol Chem] 2024 Mar; Vol. 300 (3), pp. 105689. Date of Electronic Publication: 2024 Jan 26. |
نوع المنشور: | Journal Article |
اللغة: | English |
بيانات الدورية: | Publisher: Elsevier Inc. on behalf of American Society for Biochemistry and Molecular Biology Country of Publication: United States NLM ID: 2985121R Publication Model: Print-Electronic Cited Medium: Internet ISSN: 1083-351X (Electronic) Linking ISSN: 00219258 NLM ISO Abbreviation: J Biol Chem Subsets: MEDLINE |
أسماء مطبوعة: | Publication: 2021- : [New York, NY] : Elsevier Inc. on behalf of American Society for Biochemistry and Molecular Biology Original Publication: Baltimore, MD : American Society for Biochemistry and Molecular Biology |
مواضيع طبية MeSH: | Flavins*/metabolism , Oxidoreductases*/chemistry , Oxidoreductases*/genetics , Oxidoreductases*/metabolism , Urocanic Acid*/metabolism , Shewanella*/enzymology , Shewanella*/genetics , Bacterial Proteins*/chemistry , Bacterial Proteins*/genetics , Bacterial Proteins*/metabolism, Kinetics ; Oxidation-Reduction ; Protein Domains ; Mutation ; Catalytic Domain ; Protein Conformation |
مستخلص: | Urocanate reductase (UrdA) is a bacterial flavin-dependent enzyme that reduces urocanate to imidazole propionate, enabling bacteria to use urocanate as an alternative respiratory electron acceptor. Elevated serum levels of imidazole propionate are associated with the development of type 2 diabetes, and, since UrdA is only present in humans in gut bacteria, this enzyme has emerged as a significant factor linking the health of the gut microbiome and insulin resistance. Here, we investigated the chemistry of flavin oxidation by urocanate in the isolated FAD domain of UrdA (UrdA') using anaerobic stopped-flow experiments. This analysis unveiled the presence of a charge-transfer complex between reduced FAD and urocanate that forms within the dead time of the stopped-flow instrument (∼1 ms), with flavin oxidation subsequently occurring with a rate constant of ∼60 s -1 . The pH dependence of the reaction and analysis of an Arg411Ala mutant of UrdA' are consistent with Arg411 playing a crucial role in catalysis by serving as the active site acid that protonates urocanate during hydride transfer from reduced FAD. Mutational analysis of urocanate-binding residues suggests that the twisted conformation of urocanate imposed by the active site of UrdA' facilitates urocanate reduction. Overall, this study provides valuable insight into the mechanism of urocanate reduction by UrdA. Competing Interests: Conflict of interest The authors declare that they have no conflicts of interest with the contents of this article. (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.) |
فهرسة مساهمة: | Keywords: catalytic mechanism; diabetes; enzyme kinetics; flavin; flavoenzyme; flavoprotein; imidazole propionate; isotope effects; mutagenesis; oxidative half-reaction; reductase; stopped-flow; urocanate; urocanate reductase |
المشرفين على المادة: | 0 (Flavins) EC 1.- (Oxidoreductases) G8D26XJJ3B (Urocanic Acid) 0 (Bacterial Proteins) |
SCR Organism: | Shewanella oneidensis |
تواريخ الأحداث: | Date Created: 20240127 Date Completed: 20240403 Latest Revision: 20240405 |
رمز التحديث: | 20240405 |
مُعرف محوري في PubMed: | PMC10882135 |
DOI: | 10.1016/j.jbc.2024.105689 |
PMID: | 38280427 |
قاعدة البيانات: | MEDLINE |
تدمد: | 1083-351X |
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DOI: | 10.1016/j.jbc.2024.105689 |