Comparison of an ST80 MRSA strain from the USA with European ST80 strains.
OBJECTIVE
A number of community-acquired MRSA (CA-MRSA) clonal lineages dominate worldwide. ST80 was dominant in Europe and has increasingly been described from the Middle East. Here we report the whole genome sequence of the first ST80 CA-MRSA from the USA.


METHODS
CA-MRSA isolate S0924 was obtained from a patient admitted to Cook County Hospital (Chicago, IL, USA) who came from Syria; the isolate belonged to spa type t044 and ST80. The whole genome sequence of S0924 was determined and compared with three previously published whole genome sequences of ST80 CA-MRSA from Europe and a newly sequenced ST80 CA-MRSA from the Netherlands (S1475).


RESULTS
Based on spa typing, SCCmec type and virulence gene profile, this US ST80 isolate is indistinguishable from the European CA-MRSA ST80 clone. SNP analysis within the conserved core genome showed clear differences between the strains with up to 144 SNPs differing between S0924 and strain S1800, an ST80 MRSA from Greece. The gene content showed 21 regions of difference between the US and European isolates, although these were largely restricted to mobile genetic elements. Phylogenetic reconstruction indicated that the European strains were more closely related to each other than to the US strain. The SNP data suggest that a common ancestor existed around two decades ago, indicating that the US and European ST80 strains are clonally linked.


CONCLUSIONS
These data combined with the country of origin of the patient suggest that ST80 S0924 was probably relatively recently introduced into the USA from Syria.
Department of Medical Microbiology, University Medical Centre Utrecht, Utrecht, The Netherlands a.c.fluit@umcutrecht.nl.
Ad C
AC
Fluit
Department of Medical Microbiology, University Medical Centre Utrecht, Utrecht, The Netherlands.
Neeltje
N
Carpaij
Department of Medical Microbiology, University Medical Centre Utrecht, Utrecht, The Netherlands.
Eline A M
EA
Majoor
Department of Infectious Diseases, Rush University Medical Center, Chicago, IL, USA.
Robert A
RA
Weinstein
Department of Infectious Diseases, Rush University Medical Center, Chicago, IL, USA.
Alla
A
Aroutcheva
Division of Infectious Disease, John H. Stroger Jr. Hospital of Cook County, Chicago, IL, USA.
Thomas W
TW
Rice
Department of Medical Microbiology, University Medical Centre Utrecht, Utrecht, The Netherlands.
Marc J M
MJ
Bonten
Department of Medical Microbiology, University Medical Centre Utrecht, Utrecht, The Netherlands.
Rob J L
RJ
Willems
D002641:Chicago; D017714:Community-Acquired Infections / Q000382:microbiology*; D004269:DNA, Bacterial / Q000737:chemistry* / Q000235:genetics*; D005060:Europe; D014644:Genetic Variation; D016680:Genome, Bacterial; D005838:Genotype; D006801:Humans; D055624:Methicillin-Resistant Staphylococcus aureus / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification; D008969:Molecular Sequence Data; D058889:Molecular Typing; D017422:Sequence Analysis, DNA; D013203:Staphylococcal Infections / Q000382:microbiology*; D013593:Syria; D037521:Virulence Factors / Q000235:genetics
D004269:DNA, Bacterial; D037521:Virulence Factors
CA-MRSA; US; whole genome sequencing