The University of Southampton
University of Southampton Institutional Repository

Studies on the inhibition of Escherichia coli Phospho-N-acetylmuramyl-pentapeptide Translocase

Studies on the inhibition of Escherichia coli Phospho-N-acetylmuramyl-pentapeptide Translocase
Studies on the inhibition of Escherichia coli Phospho-N-acetylmuramyl-pentapeptide Translocase

The problem of antibiotic resistance is an ever increasing threat to modern healthcare and there is an urgent need for the development of new antibacterial agents. Phospho-N-acetylmuramyl-pentapeptide translocase (translocase I) catalyses the first membrane step in the biosynthesis of the bacterial cell wall polymer peptidoglycan, and is a potential enzyme target for such novel agents. The mraY gene encoding for translocase I in E. coli has been cloned, overexpressed and the integral membrane protein solubilised with detergent.

Mureidomycin A (MRD A) is a peptidyl nucleoside antibiotic which has been characterised as a slow-binding inhibitor of translocase II (IC50 <0.1 μM). Selective modification of the primary amino and phenolic hydroxyl groups of MRD A has furnished derivatives which have been demonstrated to retain inhibitory activity against translocase I in a radiochemical assay (IC50 7.0-132 μM).

A uridine-based analogue of the unusual enamide moiety present in MRD A has been synthesised via aza-Wittig methodology. Experiments have demonstrated that this compound exhibits unexpected chemical stability, consistent with the observed inertness of the natural product. These results suggest that the enamide moiety is not involved in any active site chemistry, and leads to the hypothesis that the EI to EI* transition of slow-binding inhibition may be a conformational change.

Several potential translocase I inhibitors have been synthesised via the selective 5'-O-modification of uridine. Reversible enzyme inhibition by 5'-O-(ω-aminoacyl)uridines was shown to be dependent on the acyl chain length (3-aminopropanoyl-IC50 0.26 mM, 7-aminoheptanoyl- IC50 1.5 mM). There was also evidence for irreversible inhibition of translocase I by 5'-O-[3-{ethyl}phosphonate)propyl] uridine (IC50 3.7 mM). These compounds provide the basis for the rational design of more potent enzyme inhibitors.

University of Southampton
Gentle, Caragh Ann
Gentle, Caragh Ann

Gentle, Caragh Ann (1998) Studies on the inhibition of Escherichia coli Phospho-N-acetylmuramyl-pentapeptide Translocase. University of Southampton, Doctoral Thesis.

Record type: Thesis (Doctoral)

Abstract

The problem of antibiotic resistance is an ever increasing threat to modern healthcare and there is an urgent need for the development of new antibacterial agents. Phospho-N-acetylmuramyl-pentapeptide translocase (translocase I) catalyses the first membrane step in the biosynthesis of the bacterial cell wall polymer peptidoglycan, and is a potential enzyme target for such novel agents. The mraY gene encoding for translocase I in E. coli has been cloned, overexpressed and the integral membrane protein solubilised with detergent.

Mureidomycin A (MRD A) is a peptidyl nucleoside antibiotic which has been characterised as a slow-binding inhibitor of translocase II (IC50 <0.1 μM). Selective modification of the primary amino and phenolic hydroxyl groups of MRD A has furnished derivatives which have been demonstrated to retain inhibitory activity against translocase I in a radiochemical assay (IC50 7.0-132 μM).

A uridine-based analogue of the unusual enamide moiety present in MRD A has been synthesised via aza-Wittig methodology. Experiments have demonstrated that this compound exhibits unexpected chemical stability, consistent with the observed inertness of the natural product. These results suggest that the enamide moiety is not involved in any active site chemistry, and leads to the hypothesis that the EI to EI* transition of slow-binding inhibition may be a conformational change.

Several potential translocase I inhibitors have been synthesised via the selective 5'-O-modification of uridine. Reversible enzyme inhibition by 5'-O-(ω-aminoacyl)uridines was shown to be dependent on the acyl chain length (3-aminopropanoyl-IC50 0.26 mM, 7-aminoheptanoyl- IC50 1.5 mM). There was also evidence for irreversible inhibition of translocase I by 5'-O-[3-{ethyl}phosphonate)propyl] uridine (IC50 3.7 mM). These compounds provide the basis for the rational design of more potent enzyme inhibitors.

This record has no associated files available for download.

More information

Published date: 1998

Identifiers

Local EPrints ID: 463534
URI: http://eprints.soton.ac.uk/id/eprint/463534
PURE UUID: 25a5a96b-e170-42fb-8e2b-a724b166dbbe

Catalogue record

Date deposited: 04 Jul 2022 20:53
Last modified: 04 Jul 2022 20:53

Export record

Contributors

Author: Caragh Ann Gentle

Download statistics

Downloads from ePrints over the past year. Other digital versions may also be available to download e.g. from the publisher's website.

View more statistics

Atom RSS 1.0 RSS 2.0

Contact ePrints Soton: eprints@soton.ac.uk

ePrints Soton supports OAI 2.0 with a base URL of http://eprints.soton.ac.uk/cgi/oai2

This repository has been built using EPrints software, developed at the University of Southampton, but available to everyone to use.

We use cookies to ensure that we give you the best experience on our website. If you continue without changing your settings, we will assume that you are happy to receive cookies on the University of Southampton website.

×