Proximity channeling during cyanobacterialphycoerythrobilin synthesis
- Substrate channeling is a widespread mechanism in metabolic pathways to avoid decomposition of unstable intermediates, competing reactions, and to accelerate catalytic turnover. During the biosynthesis of light-harvesting phycobilins in cyanobacteria, two members of the ferredoxin-dependent bilin reductases are involved in the reduction of the open-chain tetrapyrrole biliverdin IXα to the pink pigment phycoerythrobilin. The first reaction is catalyzed by 15,16-dihydrobiliverdin:ferredoxin oxidoreductase and produces the unstable intermediate 15,16-dihydrobiliverdin (DHBV). This intermediate is subsequently converted by phycoerythrobilin:ferredoxin oxidoreductase to the final product phycoerythrobilin. Although substrate channeling has been postulated already a decade ago, detailed experimental evidence was missing. Using a new on-column assay employing immobilized enzyme in combination with UV-Vis and fluorescence spectroscopy revealed that both enzymes transiently interact and that transfer of the intermediate is facilitated by a significantly higher binding affinity of DHBV toward phycoerythrobilin:ferredoxin oxidoreductase. Concluding from the presented data, the intermediate DHBV is transferred via proximity channeling.
Author: | Marco Aras, Volker Hartmann, Jana Hartmann, Marc M. Nowaczyk, Nicole Frankenberg-DinkelORCiD |
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URN: | urn:nbn:de:hbz:386-kluedo-79672 |
DOI: | https://doi.org/10.1111/febs.15003 |
ISSN: | 1742-4658 |
Parent Title (English): | The FEBS Journal |
Publisher: | Wiley |
Document Type: | Article |
Language of publication: | English |
Date of Publication (online): | 2024/04/08 |
Year of first Publication: | 2019 |
Publishing Institution: | Rheinland-Pfälzische Technische Universität Kaiserslautern-Landau |
Date of the Publication (Server): | 2024/04/08 |
Issue: | 287/2 |
Page Number: | 11 |
First Page: | 284 |
Last Page: | 294 |
Source: | https://febs.onlinelibrary.wiley.com/doi/10.1111/febs.15003 |
Faculties / Organisational entities: | Kaiserslautern - Fachbereich Biologie |
DDC-Cassification: | 5 Naturwissenschaften und Mathematik / 570 Biowissenschaften, Biologie |
Collections: | Open-Access-Publikationsfonds |
Licence (German): | Zweitveröffentlichung |