MEP pathway products allosterically promote monomerization of deoxy-D-xylulose-5-phosphate synthase to feedback-regulate their supply

Di, X. ; Ortega-Alarcon, David (Universidad de Zaragoza) ; Kakumanu, Ramu ; Iglesias-Fernandez, Javier ; Diaz, Lucia ; Baidoo, Edward E.K. ; Velazquez-Campoy, Adrian (Universidad de Zaragoza) ; Rodríguez-Concepción, Manuel ; Perez-Gil, Jordi

Resumen: Isoprenoids are a very large and diverse family of metabolites required by all living organisms. All isoprenoids derive from the double-bond isomers isopentenyl diphosphate (IPP) and dimethylallyl diphosphate (DMAPP), which are produced by the methylerythritol 4-phosphate (MEP) pathway in bacteria and plant plastids. It has been reported that IPP and DMAPP feedback-regulate the activity of deoxyxylulose 5-phosphate synthase (DXS), a dimeric enzyme that catalyzes the main flux-controlling step of the MEP pathway. Here we provide experimental insights into the underlying mechanism. Isothermal titration calorimetry and dynamic light scattering approaches showed that IPP and DMAPP can allosterically bind to DXS in vitro, causing a size shift. In silico ligand binding site analysis and docking calculations identified a potential allosteric site in the contact region between the two monomers of the active DXS dimer. Modulation of IPP and DMAPP contents in vivo followed by immunoblot analyses confirmed that high IPP/DMAPP levels resulted in monomerization and eventual aggregation of the enzyme in bacterial and plant cells. Loss of the enzymatically active dimeric conformation allows a fast and reversible reduction of DXS activity in response to a sudden increase or decrease in IPP/DMAPP supply, whereas aggregation and subsequent removal of monomers that would otherwise be available for dimerization appears to be a more drastic response in the case of persistent IPP/DMAPP overabundance (e.g., by a blockage in their conversion to downstream isoprenoids). Our results represent an important step toward understanding the regulation of the MEP pathway and rational design of biotechnological endeavors aimed at increasing isoprenoid contents in microbial and plant systems.

Idioma: Inglés

DOI: 10.1016/j.xplc.2022.100512

Año: 2022

Publicado en: Plant Communications 4, 3 (2022), 100512 [12 pp.]
ISSN: 2590-3462

Factor impacto JCR: 10.5 (2022)

Categ. JCR: PLANT SCIENCES rank: 8 / 239 = 0.033 (2022) - Q1 - T1
Categ. JCR: BIOCHEMISTRY & MOLECULAR BIOLOGY rank: 27 / 285 = 0.095 (2022) - Q1 - T1

Factor impacto CITESCORE: 12.7 - Biochemistry, Genetics and Molecular Biology (Q1)

Factor impacto SCIMAGO: 2.985 - Biochemistry (Q1) - Biotechnology (Q1) - Plant Science (Q1) - Molecular Biology (Q1) - Cell Biology (Q1)

Financiación: info:eu-repo/grantAgreement/ES/AEI/PCI2021-121941
Financiación: info:eu-repo/grantAgreement/ES/AEI/PID2020-115810GB-I00
Financiación: info:eu-repo/grantAgreement/ES/CSIC/PIE-202040E299
Financiación: info:eu-repo/grantAgreement/EC/FP7/627639/EU/Revealing the hidden secrets of the MEP pathway to engineer new bio-resources for humanity/BIOHELP
Financiación: info:eu-repo/grantAgreement/ES/MCIU-AEI-FEDER/BES-2017-080739
Financiación: info:eu-repo/grantAgreement/ES/MINECO/FEDER/BFU2016-78232-P

Tipo y forma: Artículo (Versión definitiva)

Área (Departamento): Área Bioquímica y Biolog.Mole. (Dpto. Bioq.Biolog.Mol. Celular)