Staphylococcus aureus Pathogenesis Based on Genetic Background

Staphylococcus aureus is a common pathogen. Although it is always present in or near humans and animals, it can sometimes unleash its pathogenic potential and lead to diseases, including death. Consequently, it is considered “one of the most familiar pathogens” among pathogenic bacteria. Moreover, this pathogen is highly flexible. That is, it appears at first glance to be a complex and elusive combination of factors. While some pathogenic bacteria possess limited or defined characteristics, such as causing disease exclusively in specific hosts or through specific virulent factors, S. aureus displays a wide spectrum of diseases across various hosts, ranging from mild to fatal. This ubiquitous phenomenon is one of the distinctive features of S. aureus. Regarding pathogenicity, microbial virulence typically manifests in two modes: one characterized by a dominant and well-defined virulence factor, and another lacking such clarity. The former often presents a clear pathogenesis to the host, while the latter tends to exhibit a more varied or ambiguous pathogenesis. S. aureus falls into the latter category, lacking a singular definitive virulence factor. Instead, it possesses various combinations of virulence factors, resulting in diverse pathological outcomes. This versatility stems from the acquisition of mobile genetic elements like plasmids and bacteriophages, which complement virulence factors in the core genome. Since its discovery in the nineteenth century, there has been continuous interest in how virulence factors, like toxins and adherence factors produced by S. aureus, influence disease development. The absence of a conclusive answer has posed challenges in developing vaccines against this bacterium. The absence of a commercial vaccine has spurred intense research efforts worldwide. In this review, the flexibility and adaptability of S. aureus as pathogenic agent will be described.