NMR structures and mutational analysis of the two peptides constituting the bacteriocin plantaricin S.
 

NMR structures and mutational analysis of the two peptides constituting the bacteriocin plantaricin S.

http://www.bionmr.com//www.ncbi.nlm....ges-lo_npg.gif http://www.bionmr.com//www.ncbi.nlm....pubmed-pmc.png Related Articles NMR structures and mutational analysis of the two peptides constituting the bacteriocin plantaricin S.

Sci Rep. 2019 02 20;9(1):2333

Authors: Ekblad B, Kristiansen PE

Abstract
The structure of the individual peptides of the two-peptide bacteriocin plantaricin S, an antimicrobial peptide produced by a Lactobacillus plantarum strain, has been determined in DPC micelles. The two peptides of plantaricin S, Pls-? and Pls-?, form an ?-helix from and including residue 8 to 24 with a less structured region around residue 16-19 and an amphiphilic ?-helix from and including residue 7 to 23, respectively. Activity assays on single amino acid-substituted GxxxG and GxxxG-like motifs show that substituting the Ser and Gly residues in the G9xxxG13 motif in Pls-? and the S17xxxG21 motif in Pls-? reduced or drastically reduced the antimicrobial activity. The two-peptide bacteriocin muricidin contains GxxxG-like motifs at similar positions and displays 40-50% amino acid identity with plantaricin S. Activity assays of combinations of the peptides that constitute the bacteriocins plantaricin S and muricidin show that some combinations are highly active. Furthermore, sequence alignments show that the motifs important for plantaricin S activity align with identical motifs in muricidin. Based on sequence comparison and activity assays, a membrane-inserted model of plantaricin S in which the two peptides are oriented antiparallel relative to each other and where the GxxxG and GxxxG-like motifs important for activity come close in space, is proposed.


PMID: 30787405 [PubMed - indexed for MEDLINE]



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