What is a common characteristic of Staphylococcus aureus?

Staphylococcus aureus is notable for its ability to ferment mannitol, which is a distinguishing characteristic used in laboratory identification. When grown on mannitol salt agar, Staphylococcus aureus ferments mannitol and produces acid, which causes a change in the color of the medium from red to yellow. This ability to utilize mannitol is key in differentiating it from other staphylococcal species that do not exhibit this fermentation.

Understanding this characteristic is essential for microbiology as it not only aids in the identification of Staphylococcus aureus in clinical specimens but also highlights its metabolic versatility. The other options involve characteristics that do not accurately represent Staphylococcus aureus. For example, it is important to note that while Staphylococcus aureus can produce toxins, not all such toxins are heat-stable, and it is not resistant to all antibiotics, as certain antibiotics remain effective against it depending on the strain. Additionally, Staphylococcus aureus is not a spore-forming bacterium, which further emphasizes the correctness of the fermentation of mannitol as a key trait.