A BTP1 prophage gene present in invasive non-typhoidal Salmonella determines composition and length of the O-antigen of the lipopolysaccharide

TY - JOUR

T1 - A BTP1 prophage gene present in invasive non-typhoidal Salmonella determines composition and length of the O-antigen of the lipopolysaccharide

AU - Kintz, Erica

AU - Davies, Mark

AU - Hammarlöf, Disa L

AU - Canals, Rocío

AU - Hinton, Jay C D

AU - van der Woude, Marjan

N1 - © 2015 The Authors. Molecular Microbiology published by John Wiley & Sons Ltd. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

PY - 2015/4

Y1 - 2015/4

N2 - Salmonella Typhimurium isolate D23580 represents a recently identified ST313 lineage of invasive non-Typhoidal Salmonellae (iNTS). One of the differences between this lineage and other non-iNTS S. Typhimurium isolates is the presence of prophage BTP1. This prophage encodes a gtrC gene, implicated in O-antigen modification. GtrC(BTP1) is essential for maintaining O-antigen length in isolate D23580, since a gtr(BTP1) mutant yields a short O-antigen. This phenotype can be complemented by gtrC(BTP1) or very closely related gtrC genes. The short O-antigen of the gtr(BTP1) mutant was also compensated by deletion of the BTP1 phage tailspike gene in the D23580 chromosome. This tailspike protein has a putative endorhamnosidase domain and thus may mediate O-antigen cleavage. Expression of the gtrC(BTP1) gene is, in contrast to expression of many other gtr operons, not subject to phase variation and transcriptional analysis suggests that gtrC is produced under a variety of conditions. Additionally, GtrC(BTP1) expression is necessary and sufficient to provide protection against BTP1 phage infection of an otherwise susceptible strain. These data are consistent with a model in which GtrC(BTP1) mediates modification of the BTP1 phage O-antigen receptor in lysogenic D23580, and thereby prevents superinfection by itself and other phage that use the same O-antigen co-receptor.

AB - Salmonella Typhimurium isolate D23580 represents a recently identified ST313 lineage of invasive non-Typhoidal Salmonellae (iNTS). One of the differences between this lineage and other non-iNTS S. Typhimurium isolates is the presence of prophage BTP1. This prophage encodes a gtrC gene, implicated in O-antigen modification. GtrC(BTP1) is essential for maintaining O-antigen length in isolate D23580, since a gtr(BTP1) mutant yields a short O-antigen. This phenotype can be complemented by gtrC(BTP1) or very closely related gtrC genes. The short O-antigen of the gtr(BTP1) mutant was also compensated by deletion of the BTP1 phage tailspike gene in the D23580 chromosome. This tailspike protein has a putative endorhamnosidase domain and thus may mediate O-antigen cleavage. Expression of the gtrC(BTP1) gene is, in contrast to expression of many other gtr operons, not subject to phase variation and transcriptional analysis suggests that gtrC is produced under a variety of conditions. Additionally, GtrC(BTP1) expression is necessary and sufficient to provide protection against BTP1 phage infection of an otherwise susceptible strain. These data are consistent with a model in which GtrC(BTP1) mediates modification of the BTP1 phage O-antigen receptor in lysogenic D23580, and thereby prevents superinfection by itself and other phage that use the same O-antigen co-receptor.

U2 - 10.1111/mmi.12933

DO - 10.1111/mmi.12933

M3 - Article

C2 - 25586744

SN - 0950-382X

VL - 96

SP - 263

EP - 275

JO - Molecular Microbiology

JF - Molecular Microbiology

IS - 2

ER -