Pathogenomic analysis of the common bovine Staphylococcus aureus clone (ET3): emergence of a virulent subtype with potential risk to public health.
A common clone (ET3) of Staphylococcus aureus is responsible for a large proportion of cases of bovine mastitis and occasionally causes zoonotic infections of humans. In the present study, we report the identification of a virulent clonal subtype (ST151) of ET3, which resulted in increased tissue damage and mortality in a mouse model of mastitis. ST151 has undergone extensive diversification in virulence and regulatory-gene content, including the acquisition of genetic elements encoding toxins not made by other ET3 strains. Furthermore, ST151 had elevated levels of RNAIII and cytolytic toxin-gene expression, consistent with the enhanced virulence observed during experimental infection. Previously, the ST151 clone was shown to be hypersusceptible to the acquisition of vancomycin-resistance genes from Enterococcus spp. Taken together, these data indicate the emergence of a virulent subtype of the common ET3 clone, which could present an enhanced risk to public health.
Guinane
Caitriona M
CM
Centre for Infectious Diseases, The Chancellor's Building, New Royal Infirmary, University of Edinburgh, Edinburgh, Scotland, United Kingdom.
Sturdevant
Daniel E
DE
Herron-Olson
Lisa
L
Otto
Michael
M
Smyth
Davida S
DS
Villaruz
Amer E
AE
Kapur
Vivek
V
Hartigan
Patrick J
PJ
Smyth
Cyril J
CJ
Fitzgerald
J Ross
JR
D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D001427:Bacterial Toxins / Q000235:genetics / Q000378:metabolism; D002417:Cattle; D005260:Female; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D008321:Mammary Glands, Animal / Q000382:microbiology / Q000473:pathology*; D008414:Mastitis, Bovine / Q000382:microbiology / Q000401:mortality / Q000473:pathology*; D051379:Mice; D020411:Oligonucleotide Array Sequence Analysis; D011634:Public Health; D012329:RNA, Bacterial / Q000235:genetics / Q000378:metabolism; D012307:Risk Factors; D013203:Staphylococcal Infections / Q000382:microbiology / Q000401:mortality / Q000473:pathology; D013211:Staphylococcus aureus / Q000145:classification / Q000235:genetics* / Q000472:pathogenicity*; D014774:Virulence
D001426:Bacterial Proteins; D001427:Bacterial Toxins; D012329:RNA, Bacterial; C096035:RNAIII, Staphylococcus aureus