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Title: Sensitivity to the two peptide bacteriocin plantaricin EF is dependent on CorC , a membrane‐bound, magnesium/cobalt efflux protein
Abstract

Lactic acid bacteria produce a variety of antimicrobial peptides known as bacteriocins. Most bacteriocins are understood to kill sensitive bacteria through receptor‐mediated disruptions. Here, we report on the identification of theLactobacillus plantarumplantaricin EF (PlnEF) receptor. Spontaneous PlnEF‐resistant mutants of the PlnEF‐indicator strainL. plantarumNCIMB 700965 (LP965) were isolated and confirmed to maintain cellular ATP levels in the presence of PlnEF. Genome comparisons resulted in the identification of a single mutated gene annotated as the membrane‐bound, magnesium/cobalt efflux protein CorC. All isolates contained a valine (V) at position 334 instead of a glycine (G) in a cysteine‐β‐synthase domain at the C‐terminal region of CorC. In silico template‐based modeling of this domain indicated that the mutation resides in a loop between two β‐strands. The relationship between PlnEF, CorC, and metal homeostasis was supported by the finding that PlnEF‐resistance was lost when PlnEF was applied together with high concentrations of Mg2+, Co2+, Zn2+, or Cu2+. Lastly, PlnEF sensitivity was increased upon heterologous expression of LP965corCbut not the G334V CorC mutant in the PlnEF‐resistant strainLactobacillus caseiBL23. These results show that PlnEF kills sensitive bacteria by targeting CorC.

 
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NSF-PAR ID:
10459734
Author(s) / Creator(s):
 ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
MicrobiologyOpen
Volume:
8
Issue:
11
ISSN:
2045-8827
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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