Type

Journal Article

Authors

Colin Hill
R Paul Ross
John R Tagg
Orla O'Sullivan
Paula O'Connor
Paul D. Cotter
Eileen B O'Connor

Subjects

Microbiology

Topics
models molecular chemistry amino acid sequence conserved sequence lacticin 481 structure activity relationship genetics genes bacterial anti bacterial agents therapeutic use genetic variation staphylococcus aureus lactococcus lactis peptides molecular conformation staphylococcin evolution molecular bacteriocins

Relatedness between the two-component lantibiotics lacticin 3147 and staphylococcin C55 based on structure, genetics and biological activity. (2006)

Abstract Two component lantibiotics, such as the plasmid-encoded lacticin 3147 produced by Lactococcus lactis DPC3147 and staphylococcin C55 produced by Staphylococcus aureus C55, represent an emerging subgroup of bacteriocins. These two bacteriocins are particularly closely related, exhibiting 86% (LtnA1 and C55alpha) and 55% (LtnA2 and C55beta) identity in their component peptides. The aim of this study was to investigate, for the first time for any two component bacteriocins, the significance of the relatedness between these two systems. So close is this relatedness that the hybrid peptide pairs LtnA1:C55beta and C55alpha:LtnA2 were found to have activities in the single nanomolar range, comparing well with the native pairings. To determine whether this flexibility extended to the associated post-translational modification/processing machinery, the staphylococcin C55 structural genes were directly substituted for their lacticin 3147 counterparts in the ltn operon on the large conjugative lactococcal plasmid pMRC01. It was established that the lacticin LtnA1 post-translational and processing machinery could produce functionally active C55alpha, but not C55beta. In order to investigate in closer detail the significance of the differences between LtnA1 and C55alpha, three residues in LtnA1 were replaced with the equivalent residues in C55alpha. Surprisingly, one such mutant LtnA1-Leu21Ala was not produced. This may be significant given the positioning of this residue in a putative lipid II binding loop. It is apparent, despite sharing striking similarities in terms of structure and activity, that these two complex bacteriocins display some highly dedicated features particular to either system.
Collections Ireland -> Teagasc -> PubMed

Full list of authors on original publication

Colin Hill, R Paul Ross, John R Tagg, Orla O'Sullivan, Paula O'Connor, Paul D. Cotter, Eileen B O'Connor

Experts in our system

1
Colin Hill
University College Cork
Total Publications: 351
 
2
R Paul Ross
Teagasc
Total Publications: 441
 
3
Orla O'Sullivan
Teagasc
Total Publications: 92
 
4
Paula M. O'Connor
Teagasc
Total Publications: 85
 
5
Paul D. Cotter
Teagasc
Total Publications: 253