Metabolic pathway rerouting in Paraburkholderia rhizoxinica evolved long-overlooked derivatives of coenzyme F420

Braga, D.; Last, D.; Hasan, M.; Guo, H.; Leichnitz, D.; Uzum, Z.; Richter, I.; Schalk, F.; Beemelmanns, C.; Hertweck, C.; Lackner, G.

doi:10.1101/670455

bioRxiv · 10.1101/670455

Metabolic pathway rerouting in Paraburkholderia rhizoxinica evolved long-overlooked derivatives of coenzyme F420

Braga, D.·Last, D.·Hasan, M.·Guo, H.·Leichnitz, D.·Uzum, Z.·Richter, I.·Schalk, F.·Beemelmanns, C.·Hertweck, C.·Lackner, G.

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Abstract

Coenzyme F420 is a specialized redox cofactor with a highly negative redox potential. It supports biochemical processes like methanogenesis, degradation of xenobiotics or the biosynthesis of antibiotics. Although well-studied in methanogenic archaea and actinobacteria, not much is known about F420 in Gram-negative bacteria. Genome sequencing revealed F420 biosynthetic genes in the Gram-negative, endofungal bacterium Paraburkholderia rhizoxinica, a symbiont of phytopathogenic fungi. Fluorescence microscopy, high-resolution LC-MS, and structure elucidation by NMR demonstrated that the encoded pathway is active and yields unexpected derivatives of F420 (3PG-F420). Further analyses of a biogas-producing microbial community showed that these derivatives are more widespread in nature. Genetic and biochemical studies of their biosynthesis established that a specificity switch in the guanylyltransferase CofC re-programmed the pathway to start from 3-phospho-D-glycerate, suggesting a rerouting event during the evolution of F420 biosynthesis. Furthermore, the cofactor activity of 3PG-F420 was validated, thus opening up perspectives for its use in biocatalysis. The 3PG-F420 biosynthetic gene cluster is fully functional in Escherichia coli, enabling convenient production of the cofactor by fermentation.

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Braga, D., Last, D., Hasan, M., Guo, H., Leichnitz, D., Uzum, Z., Richter, I., Schalk, F., Beemelmanns, C., Hertweck, C., Lackner, G.. 2019-06-13. Metabolic pathway rerouting in Paraburkholderia rhizoxinica evolved long-overlooked derivatives of coenzyme F420. https://doi.org/10.1101/670455

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