Antibiotic Susceptibility Profiling of Human Pathogenic <i>Staphylococcus aureus</i> Strains Using Whole Genome Sequencing and Genome-Scale Annotation Approaches

oleh: Mejdi Snoussi, Emira Noumi, Nouha Bouali, Abdulrahman S. Bazaid, Mousa M. Alreshidi, Hisham N. Altayb, Kamel Chaieb

Format: Article
Diterbitkan: MDPI AG 2023-04-01

Deskripsi

<i>Staphylococcus</i> species are major pathogens with increasing importance due to the rise in antibiotic resistance. Whole genome sequencing and genome-scale annotation are promising approaches to study the pathogenicity and dissemination of virulence factors in nosocomial methicillin-resistant and multidrug-resistant bacteria in intensive care units. Draft genome sequences of eight clinical <i>S. aureus</i> strains were assembled and annotated for the prediction of antimicrobial resistance genes, virulence factors, and phylogenetic analysis. Most of the studied <i>S. aureus</i> strains displayed multi-resistance toward the tested drugs, reaching more than seven drugs up to 12 in isolate S22. The <i>mecA</i> gene was detected in three isolates (S14, S21, and S23), <i>mecC</i> was identified in S8 and S9, and <i>blaZ</i> was commonly identified in all isolates except strain S23. Additionally, two complete mobile genomic islands coding for methicillin resistance SCCmec Iva (2B) were identified in strains S21 and S23. Numerous antimicrobial resistance genes (<i>nor</i>A, <i>norC</i>, <i>MgrA</i>, <i>tet</i>(45), APH(3′)-IIIa, and AAC(6′)-APH(2″)) were identified in chromosomes of different strains. Plasmid analysis revealed the presence of <i>blaZ</i>, <i>tetK</i>, and <i>ermC</i> in different plasmid types, located in gene cassettes containing plasmid replicons (rep) and insertion sequences (IS). Additionally, the aminoglycoside-resistant determinants were identified in S1 (APH(3′)-IIIa), while AAC(6)-APH(2″) was detected in strains S8 and S14. The trimethoprim (<i>dfrC</i>) resistance gene was detected in <i>S. aureus</i> S21, and the fosfomycin (<i>fosB</i>) resistance gene was detected only in <i>S. aureus</i> S14. We also noted that <i>S. aureus</i> S1 belongs to ST1-t127, which has been reported as one of the most frequent human pathogen types. Additionally, we noted the presence of rare plasmid-mediated mecC-MRSA in some of our isolates.