Characterization of a community-acquired methicillin-resistant sequence type 338 Staphylococcus aureus strain containing a staphylococcal cassette chromosome mec type VT.
Int J Infect Dis. 2019 Nov 01;:
Authors: Chen Y, Hong J, Chen Y, Wang H, Yu Y, Qu T
OBJECTIVES: To determine the molecular characteristics of a sequence type 338 community-acquired methicillin-resistantStaphylococcus aureus (CA-MRSA) strain and the relationship among MRSA strains from various lineages and areas.
METHODS: We performed whole genome sequencing, genomic comparison, antimicrobial susceptibility testing and haemolysis analysis to identify the resistance determinants and virulence factors of strain ZY05 and the relationships among CC59 clones.
RESULTS: MRSA strain ZY05 was resistant to tetracycline, erythromycin and clindamycin, and the resistance genes erm(B) and tet(K) were detected in the genome. ZY05 harbours the genomic islands νSaα, νSaβ, νSaγ and ΦSa2, the pathogenicity island νSa1, and virulence factors, such as Panton-Valentine leukocidin, phenol-soluble Modulins, alpha haemolysin, enterotoxin B, enterotoxin K, and enterotoxin Q, which were the same as those present in ST59 strains. In addition, the virulence potential of ST338 did not differ from that of ST59. This strain contains the staphylococcal cassette chromosome mec (SCCmec) type VT, a distinct SCCmec type previously reported from Taiwan. The results of cgMLST analysis showed that the gene distances between ST59 and ST338 were close among CC59 isolates, while strains from Taiwan were identical to isolates from the Chinese mainland with respect to these two STs.
CONCLUSIONS: The ST338 strain ZY05, which has close genetic relationship with ST59 strains, is multi-drug resistant and highly virulent. Strains of two identical lineages, ST59 and ST338, from Taiwan and the Chinese mainland may have the same genetic background.
PMID: 31682959 [PubMed - as supplied by publisher]