Issue 5, 2017

Elucidation of salicylate attachment in celesticetin biosynthesis opens the door to create a library of more efficient hybrid lincosamide antibiotics

Abstract

Lincosamides, which are produced by streptomycetes, compose a small but clinically important class of antibiotics. The recent elucidation of the condensation and post-condensation biosynthetic steps of the lincosamides lincomycin and celesticetin revealed several unexpected reaction mechanisms. Here, we prepared recombinant proteins involved in the celesticetin biosynthetic pathway and used them for in vitro assays that were monitored by LC-MS. Our results elucidate the last biosynthetic step of celesticetin: the attachment of salicylic acid is catalyzed by the Ccb2 acyl-CoA ligase and the Ccb1 acyltransferase. Ccb1 belongs to the WS/DGAT protein family and, in contrast to the characterized members of the family, has unusual substrate specificity. To the best of our knowledge, Ccb1 is the first protein in this family that transfers a benzoyl derivative-CoA conjugate and is the first WS/DGAT protein involved in the biosynthesis of secondary metabolites. Furthermore, we exploited the relaxed substrate specificities of Ccb1 and Ccb2, as well as three additional upstream post-condensation biosynthetic proteins in the celesticetin pathway, and combined the lincomycin and the celesticetin biosynthetic pathways in vitro. In this way, we prepared a library of 150 novel hybrid lincosamides, including two unnatural chimeras of lincomycin and celesticetin, which were shown to have antibacterial properties more pronounced than clinically used lincomycin. These achievements may be considered a case study in applying knowledge about biosynthetic machinery to assemble a large number of compounds from originally a small group of natural products without the need for chemical synthesis.

Graphical abstract: Elucidation of salicylate attachment in celesticetin biosynthesis opens the door to create a library of more efficient hybrid lincosamide antibiotics

Supplementary files

Article information

Article type
Edge Article
Submitted
22 Sep 2016
Accepted
27 Feb 2017
First published
23 Mar 2017
This article is Open Access

All publication charges for this article have been paid for by the Royal Society of Chemistry
Creative Commons BY license

Chem. Sci., 2017,8, 3349-3355

Elucidation of salicylate attachment in celesticetin biosynthesis opens the door to create a library of more efficient hybrid lincosamide antibiotics

S. Kadlcik, Z. Kamenik, D. Vasek, M. Nedved and J. Janata, Chem. Sci., 2017, 8, 3349 DOI: 10.1039/C6SC04235J

This article is licensed under a Creative Commons Attribution 3.0 Unported Licence. You can use material from this article in other publications without requesting further permissions from the RSC, provided that the correct acknowledgement is given.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements