Question

Streptococcus mutans; is a major cause of cavities. It resides in the gum pockets, does not have catalase activity, and can be grown outside of an anaerobic chamber. The bacterium is probably which of the following?

a) Aerobe
b) Anaerobe
c) Facultative anaerobe
d) Microaerophile

Answer 1

Streptococcus mutans is a facultative anaerobe that causes cavities by fermenting sugars and producing acids in the mouth, leading to tooth decay and contributing to other oral health issues.

Correct option is c) Facultative anaerobe

Step-by-step explanation:

Streptococcus mutans, widely known as a primary cause of dental cavities, thrives in gum pockets and exhibits nil catalase activity. Despite this, it can still be cultured outside an anaerobic chamber. Such characteristics indicate that the bacterium is most likely a facultative anaerobe, as it seems to have the capability to survive in both the presence and absence of oxygen. In the oral environment, S. mutans contributes to the formation of dental biofilm plaque by metabolizing sucrose into glucose and fructose. The latter is fermented leading to organic acids that demineralize tooth enamel and dentin. These activities not only lead to cavities but can also promote other oral health issues such as tartar, gingivitis, and periodontal disease.