Draft Genome Sequence of Streptococcus equi subsp. zooepidemicus Strain S31A1, Isolated from Equine Infectious Endometritis

Abstract

We present the draft genome sequence of Streptococcus equi subsp. zooepidemicus S31A1, a strain isolated from equine infectious endometritis in Denmark. Comparative analyses of this genome were done with four published reference genomes: S. zooepidemicus strains MGCS10565, ATCC 35246, and H70 and S. equi subsp. equi strain 4047.

Streptococcus equi subsp. zooepidemicus Invades and Survives in Epithelial Cells

“…Previous studies have indicated that the M protein is triggering this uptake mechanism, and in S. pyogenes serotype M1, the M protein acts as a primary invasin (Cue et al, 1998 ). M-like proteins have been found in S. zooepidemicus and we have identified M-like proteins in the strains investigated in this study as well (Da Piedade et al, 2013 ; unpublished genome assemply of strain 1-4a). These proteins could be involved in the triggering of membrane ruffling, but further specific studies would be needed to confirm this hypothesis.…”

“…The mechanism of uptake into host cell caveolae has been linked to the binding of fibronectin to the streptococcal FnBPs and the subsequent binding to the host cell α5β1 integrins leading to integrin clustering and caveolae aggregation, which results in the forming of the large invaginations in the host cell membrane without accumulation of actin (Rohde et al, 2003 ). It can thus be speculated that the FnBPs found in the S. zooepidemicus strains investigated in this study could trigger this uptake mechanism (Da Piedade et al, 2013 ; unpublished genome assemply of strain 1-4a), even though differences in the sequence of the FnBPs between streptococcal species can lead to different uptake mechanisms (Rohde et al, 2011 ).…”

“…Putative pili loci have been identified in S. zooepidemicus (FimI-III) and loci encoding sortases (Holden et al, 2009 ), which are essential for the assembly of the pili (Ton-That and Schneewind, 2004 ). Our strain S31A1 has four sortase C genes (SrtC 1-4) and the sortase A gene (SrtA), six fimbrial subunit proteins (FszA-F), a putative pilus domain with high identity to the S. zooepidemicus SzH70 (SZO_08560), and a gene identical to the RofA/Nra-like fimbrial gene transcriptional regulator (sez_1823) in S. zooepidemicus strain MGCS 10565 (Beres et al, 2008 ; Ma et al, 2011 ; Da Piedade et al, 2013 ). In strain 1-4a we found that a large part of this gene cluster has been disrupted by a transposon and integrase, resulting in the loss of SrtC 2-4, FszC-F, and the RofA/Nra-like genes.…”

“…In S. pyogenes serotype M1 and M5 the hypervariable region, on the contrary to stimulating the immune system, seems involved in evading antibody attack through weak immunogenicity and antigenic variation (Lannergaard et al, 2011 ). S. zooepidemicus has a M-like protein (SzP), which is associated with virulence and opsonization as well (Hong-Jie et al, 2009 ), and has been explored as vaccine candidate (Velineni and Timoney, 2013 ; Lin et al, 2014 ), as well as other M-like proteins, the CspZ.1and CspZ.2 (Da Piedade et al, 2013 ; unpublished genome assembly of strain 1-4a). Like the FnBPs, M protein binding of fibronectin may lead to internalization and the M-like protein might thus have similar functions in S. zooepidemicus .…”

Bivalent Ligation of the Collagen-binding Modules of Fibronectin by SFS, a Non-anchored Bacterial Protein of Streptococcus equi

“…Interestingly, some strains of S. equi subsp. zooepidemicus, regarded as an opportunistic pathogen in humans as well as horses (19), express an SFS-like protein with only one FN-binding repeat (21,22). SFS with a single repeat is predicted to have only the loose monovalent, single-step binding to FN and not to form a stable complex with FN.…”