Advanced Dental Admission Test (ADAT)

What type of microbe is Streptococcus pyogenes?

1. Gram-negative

2. Gram-positive

3. Anaerobic

4. Fungal

The correct answer is: Gram-positive

Streptococcus pyogenes is classified as a Gram-positive bacterium. This classification is based on the bacterial cell wall structure which retains the crystal violet stain used in the Gram staining procedure, leading to a characteristic purple appearance under a microscope. Gram-positive bacteria, including Streptococcus pyogenes, have a thick peptidoglycan layer in their cell walls, which contributes to their staining properties and provides structural integrity. This microbe is also cocci-shaped and typically appears in chains when observed microscopically. Moreover, Streptococcus pyogenes is known for causing a variety of infections, such as pharyngitis (strep throat), skin infections, and more serious conditions like rheumatic fever and necrotizing fasciitis, which further emphasizes its clinical significance. Understanding the Gram-positive nature of this bacterium is crucial for effective treatment strategies and for diagnosing the infections it causes.