Streptomyces griseus produces the antibiotic Streptomycin, which inhibits protein synthesis by binding to ribosomes and preventing the binding of fMet‐tRNA. Why isn’t S. griseus harmed by its own antibiotic?

See the answer below.

Explanation:

Antibiotic-producing bacteria are generally known to have a mechanism that enables them to be resistant to their own antibiotics. The mechanism that enables them to be resistant to their own antibiotic depends largely on the mode of action of the antibiotic substance.  

Some of the popular mechanisms used by bacteria to counter their own antibiotic substance include a mutation in the target gene, production of enzymes that inactivate the antibiotic compounds, or efflux of the compounds.

In the case of Streptomyces griseus, the inactivity of streptomycin has been linked with the production of a phosphatase inhibitor that prevents streptomycin from getting access to the target site. Hence, the organism is not harmed by its own antibiotic.

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