MRSA is methicillin-resistant Staphylococcus aureus.

Methicillin-resistant Staphylococcus aureus is a common bacterium with strong toxicity. Since the advent of penicillin in the 1940s, infectious diseases caused by Staphylococcus aureus have been greatly controlled.

However, with the widespread use of penicillin, some Staphylococcus aureus produce penicillinase, which can hydrolyze the β-lactam ring, showing resistance to penicillin. Scientists have developed a new semisynthetic penicillin, methicillin, that is resistant to penicillinase.

Extended information:

There are two subgroups of bacteria in the MRSA colony: sensitive and resistant. That is, there are only a small number of bacteria in one MRSA strain, about 10-4 to 10-7. It is highly resistant to methicillin and can still survive under 50 μg/ml methicillin conditions.

Most of the bacteria in the colony are sensitive to methicillin. A large number of sensitive bacteria are killed within a few hours after using antibiotics, but a few resistant strains grow slowly and multiply rapidly a few hours later. .

Baidu Encyclopedia—MRSA