Sequence Analysis of the Variable Number Tandem Repeat in Staphylococcus aureus Protein A Gene - Bacterial Pathogenesis: Methods and Protocols - page 267

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Sequence Analysis of the Variable Number Tandem
Repeat in Staphylococcus aureus Protein A Gene
spa Typing
Barun Mathema, Jose Mediavilla, and Barry N. Kreiswirth
Summary
The analyses of numerous prokaryotic and eukaryotic genomes have revealed the
presence of variable number tandem repeats (VNTRs). VNTR analysis is currently widely
used to sub-speciate many bacterial, fungal, and viral pathogens and has facilitated a
number of molecular epidemiology studies. In this chapter, we focus on spa typing which is
based on sequence analysis of VNTRs in the polymorphic X region of the Staphylococcus
aureus protein A gene Staphylococcus aureus . As the specific methods for spa typing,
detailed in this chapter, are well-established and routine procedures (e.g., DNA isolation,
PCR and DNA sequencing) for most molecular biology laboratories, we highlight the
analytic methods used to interpret the genotyping data generated by sequence analysis and
their potential applications in local and global epidemiologic investigations.
Key Words: Staphylococcus aureus ; genotyping; variable number tandem repeats;
spa typing; epidemiology; DNA sequencing.
1. Introduction
Staphylococcus aureus has long been recognized as a major human pathogen
and remains a frequent cause of morbidity and mortality (1) . According
to the National Nosocomial Surveillance System (NNIS), S. aureus is the
most common cause of nosocomial infections (2) . These infections include
pneumonia, surgical site, and bloodstream infections, which can be complicated
by endocarditis, osteomyelitis, or septic shock (1) . The versatile tissue tropism