Remarkable geographical variations between India and Europe in carriage of the staphylococcal surface protein-encoding sasX/sesI and in the population structure of methicillin-resistant Staphylococcus aureus belonging to clonal complex 8
Objectives: sasX is a colonization-virulence factor that potentially underlies the success of methicillin-resistant Staphylococcus aureus (MRSA) sequence type (ST) 239 in Asia. We aimed to study the spread of sasX and the population structure of MRSA in two geographically distinct regions, Europe and India. Methods: MRSA (n = 128) from screening and clinical samples from tertiary care patients in 12 European countries (n = 119), and from India (n = 9) were multilocus-sequence-typed and screened for sasX and its carrier phi SP beta-like prophage by PCR. Whole genome sequencing was performed on sasX-harbouring strains from India (n = 5) and Europe (n = 2) and on a selection non-harbouring sasX (n = 36) (2 x 150 bp, Miseq, Illumina). Reads were mapped to the ST239 reference strain, TW20. Results: sasX and sesI, a sasX homologue native to Staphylococcus epidermidis, were detected in five of the nine Indian MRSA belonging to ST239 and to other sequence types of CC8. In contrast, sasX was restricted to two ST239 strains in Europe. The intact sasX and sesI carrier phi SP beta-like prophages were similar to 80 kb and similar to 118 kb, and integrated in the yeeE gene. We identified 'novel' ST239 clades in India and Serbia that showed significant differences in base substitution frequencies (0.130 and 0.007, respectively, Tamura-Nei model) (p <0.05). Conclusions: Our data highlight dissemination of sasX to non-ST239 sequence types of CC8. Detection of the S. epidermidis-associated sesI in MRSA provided unquestionable evidence of transfer between the two species. Stark differences in evolutionary rates between the novel Indian and Serbian ST239 clades identified here might be due to inherent clade characteristics or influenced by other environmental differences such as antibiotic use. (C) 2018 European Society of Clinical Microbiology and Infectious Diseases. Published by Elsevier Ltd. All rights reserved.
Source (journal)
Clinical microbiology and infection / European Society of Clinical Microbiology and Infectious Diseases. - Oxford
Oxford : 2019
1198-743X [print]
1469-0691 [online]
25 :5 (2019) , 7 p.
Pubmed ID
Full text (Publisher's DOI)
Research group
Project info
Mechanistic insights on colistin resistance in pathogenic Escherichia coli and Klebsiella species. ua_27450
Methicillin-resistant Staphylococcus au reus (MRSA}: Development of in vitro and in vivo laboratory models as predictive bridge between in vitro drug discovery and clinical evaluation. ua_32243
Insight in methicillin-resistant Staphylococcus aureus (MRSA) biofilms: identification of key determinants in biofilm formation of highly pathogenic and globally successful MRSA clones ua_35520
Publication type
Publications with a UAntwerp address
External links
Web of Science
Creation 25.06.2019
Last edited 15.11.2022
To cite this reference