Format

Send to

Choose Destination
Chem Biol. 2008 Oct 20;15(10):1035-45. doi: 10.1016/j.chembiol.2008.07.020.

Structure-activity relationship studies of the two-component lantibiotic haloduracin.

Author information

1
Department of Biochemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, IL 61801, USA.

Abstract

The lantibiotic haloduracin consists of two posttranslationally processed peptides, Halalpha and Halbeta, which act in synergy to provide bactericidal activity. An in vitro haloduracin production system was used to examine the biological impact of disrupting individual thioether rings in each peptide. Surprisingly, the Halalpha B ring, which contains a highly conserved CTLTXEC motif, was expendable. This motif has been proposed to interact with haloduracin's predicted target, lipid II. Exchange of the glutamate residue in this motif for alanine or glutamine completely abolished antibacterial activity. This study also established that Halalpha-Ser26 and Halbeta-Ser22 escape dehydration, requiring revision of the Halbeta structure previously proposed. Extracellular proteases secreted by the producer strain can remove the leader peptide, and the Halalpha cystine that is dispensable for bioactivity protects Halalpha from further proteolytic degradation.

PMID:
18940665
PMCID:
PMC2633096
DOI:
10.1016/j.chembiol.2008.07.020
[Indexed for MEDLINE]
Free PMC Article

Supplemental Content

Full text links

Icon for Elsevier Science Icon for PubMed Central
Loading ...
Support Center