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Genotyping of Staphylococcus aureus by Ribosomal Spacer PCR (RS-PCR)
Published on: November 4, 2016
Microarray based study on virulence-associated genes and resistance determinants of Staphylococcus aureus isolates
Stefan Monecke1, Peter Kuhnert, Helmut Hotzel
1Institute for Medical Microbiology and Hygiene, Faculty of Medicine, Carl Gustav Carus at the Technical University of Dresden, Fetscherstrasse 74, D-01307, Dresden, Germany. monecke@rocketmail.com
Veterinary Microbiology
|July 7, 2007
Summary
This study analyzed Staphylococcus aureus from cattle in Germany and Switzerland using DNA microarrays. Key findings reveal specific gene targets and the presence of methicillin-resistant S. aureus (MRSA) strains, highlighting interspecies transmission potential.
Area of Science:
- Veterinary Microbiology
- Bacterial Pathogenesis
- Molecular Epidemiology
Background:
- Staphylococcus aureus is a significant pathogen in both humans and animals, causing economically relevant bovine mastitis.
- Understanding the genetic diversity and virulence factors of cattle-associated S. aureus is crucial for disease control.
Purpose of the Study:
- To characterize Staphylococcus aureus isolates from cattle in Germany and Switzerland.
- To investigate the prevalence of specific virulence genes, resistance genes, and clonal complexes.
- To identify methicillin-resistant S. aureus (MRSA) strains and assess their potential for host-to-host transmission.
Main Methods:
- DNA microarray analysis targeting 144 gene loci.
- Isolation and characterization of S. aureus from 128 bovine milk samples from Germany and Switzerland.
- Strains were assigned to clonal complexes and spa types.
Main Results:
- The majority of isolates belonged to clonal complexes 8, 25, 97, or were related to strain RF122.
- High prevalence of intact beta-haemolysin (82%) and leukocidin lukF-P83/lukM (53.1%) was observed.
- Absence of staphylokinase (89.1%) and presence of exotoxin allelic variants were common.
- Two MRSA isolates were identified, including a CC8 MRSA and a ST398 MRSA, suggesting potential for interspecies transmission.
Conclusions:
- Bovine S. aureus populations exhibit distinct genetic profiles and virulence factor carriage.
- The identification of MRSA strains underscores the One Health aspect of S. aureus epidemiology.
- Further surveillance is needed to monitor the spread of specific S. aureus strains between cattle and other hosts.
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