Journalartikel

Autorenliste: Nguyen, Hai; Kresna, I Dewa Made; Böhringer, Nils; Ruel, Jeremie; de la Mora, Eugenio; Kramer, Jil-Christine; Lewis, Kim; Nicolet, Yvain; Schäberle, Till F.; Yokoyama, Kenichi

Jahr der Veröffentlichung: 2022

Seiten: 18876-18886

Zeitschrift: Journal of the American Chemical Society

Bandnummer: 144

Heftnummer: 41

ISSN: 0002-7863

eISSN: 1520-5126

Open Access Status: Green

DOI Link: https://doi.org/10.1021/jacs.2c05565

Verlag: American Chemical Society

Abstract: 
Darobactin A is a ribosomally synthesized, post-translationally modified peptide (RiPP) with potent and broad-spectrum anti Gram-negative antibiotic activity. The structure of darobactin A is characterized by an ether and C-C crosslinking. However, the specific mechanism of the crosslink formation, especially the ether crosslink, remains elusive. Here, using in vitro enzyme assays, we demonstrate that both crosslinks are formed by the DarE radical S-adenosylmethionine (SAM) enzyme in an O2-dependent manner. The relevance of the observed activity to darobactin A biosynthesis was demonstrated by proteolytic transformation of the DarE product into darobactin A. Furthermore, DarE assays in the presence of 18O2 or [18O]water demonstrated that the oxygen of the ether crosslink originates from O2 and not from water. These results demonstrate that DarE is a radical SAM enzyme that uses oxygen as a co-substrate in its physiologically relevant function. Since radical SAM enzymes are generally considered to function under anaerobic environments, the discovery of a radical SAM oxygenase represents a significant change in the paradigm and suggests that these radical SAM enzymes function in aerobic cells. Also, the study revealed that DarE catalyzes the formation of three distinct modifications on DarA; ether and C-C crosslinks and alpha,beta-desaturation. Based on these observations, possible mechanisms of the DarE-catalyzed reactions are discussed.

Harvard-Zitierstil: Nguyen, H., Kresna, I., Böhringer, N., Ruel, J., de la Mora, E., Kramer, J., et al. (2022) Characterization of a Radical SAM Oxygenase for the Ether Crosslinking in Darobactin Biosynthesis, Journal of the American Chemical Society, 144(41), pp. 18876-18886. https://doi.org/10.1021/jacs.2c05565

APA-Zitierstil: Nguyen, H., Kresna, I., Böhringer, N., Ruel, J., de la Mora, E., Kramer, J., Lewis, K., Nicolet, Y., Schäberle, T., & Yokoyama, K. (2022). Characterization of a Radical SAM Oxygenase for the Ether Crosslinking in Darobactin Biosynthesis. Journal of the American Chemical Society. 144(41), 18876-18886. https://doi.org/10.1021/jacs.2c05565