Streptococcus pyogenes can be checked by which drug disk
**Core Concept**
Streptococcus pyogenes, a Gram-positive bacterium, is responsible for various infections including strep throat and skin infections. To identify and differentiate it from other Streptococcus species, a specific antibiotic disk is used in the Kirby-Bauer disk diffusion test.
**Why the Correct Answer is Right**
The correct answer is based on the bacteriostatic effect of the antibiotic, which inhibits the growth of Streptococcus pyogenes. The antibiotic in question acts by inhibiting cell wall synthesis. This is achieved through the inhibition of the enzyme transpeptidase by the antibiotic, which is essential for the cross-linking of peptidoglycan layers in the bacterial cell wall. This mechanism of action is specific to Streptococcus pyogenes and other Gram-positive bacteria.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect as it is not the correct antibiotic used for the identification of Streptococcus pyogenes.
* **Option B:** This option is incorrect as it is not the correct antibiotic used for the identification of Streptococcus pyogenes.
* **Option D:** This option is incorrect as it is not the correct antibiotic used for the identification of Streptococcus pyogenes.
**Clinical Pearl / High-Yield Fact**
The Kirby-Bauer disk diffusion test is a widely used method for identifying and differentiating bacteria based on their antibiotic sensitivity. This test is a fundamental tool in clinical microbiology and is used to guide antibiotic therapy.
**Correct Answer: B. Bacitracin**