Which of the following bacteria is commonly part of normal skin flora?

Which of the following bacteria is commonly part of normal skin flora?

• A. Micrococcus luteus
• B. Salmonella enterica
• C. Bacillus anthracis
• D. Pseudomonas aeruginosa

Answer: (A)

Normal skin hosts a community of microorganisms that are typically harmless or beneficial. Among them, Gram-positive cocci like Micrococcus luteus are commonly found on the skin and are considered ordinary residents of the skin microbiota. They’re usually nonpathogenic in healthy individuals and persist as part of the normal flora. In contrast, Salmonella enterica is primarily an intestinal bacterium linked to foodborne illness; Bacillus anthracis is a pathogen that causes anthrax; and Pseudomonas aeruginosa is an opportunistic pathogen that thrives in moist environments and can cause infections, especially in compromised hosts. Thus, Micrococcus luteus best fits the description of a bacterium commonly part of normal skin flora.

Normal skin hosts a community of microorganisms that are typically harmless or beneficial. Among them, Gram-positive cocci like Micrococcus luteus are commonly found on the skin and are considered ordinary residents of the skin microbiota. They’re usually nonpathogenic in healthy individuals and persist as part of the normal flora. In contrast, Salmonella enterica is primarily an intestinal bacterium linked to foodborne illness; Bacillus anthracis is a pathogen that causes anthrax; and Pseudomonas aeruginosa is an opportunistic pathogen that thrives in moist environments and can cause infections, especially in compromised hosts. Thus, Micrococcus luteus best fits the description of a bacterium commonly part of normal skin flora.