Natural antibiotic

Definition

Natural antibiotics are substances produced by microorganisms that inhibit the growth of or destroy bacteria and other microbes. They are often used as a basis for developing synthetic antimicrobial drugs.

5 Must Know Facts For Your Next Test

1. Penicillin, discovered by Alexander Fleming in 1928, is one of the most famous natural antibiotics.
2. Natural antibiotics can be derived from bacteria, fungi, and plants.
3. Streptomycin, an antibiotic used to treat tuberculosis, was isolated from the soil bacterium Streptomyces griseus.
4. Natural antibiotics can have broad-spectrum or narrow-spectrum activity depending on their effectiveness against different types of bacteria.
5. Resistance to natural antibiotics can develop through genetic mutations and horizontal gene transfer among bacteria.

Review Questions

• What is an example of a natural antibiotic discovered in the early 20th century?
• From which sources can natural antibiotics be derived?
• How does bacterial resistance to natural antibiotics typically develop?

Related terms

Penicillin: An antibiotic derived from Penicillium fungi that inhibits bacterial cell wall synthesis.

Streptomycin: An antibiotic obtained from Streptomyces griseus, effective against Mycobacterium tuberculosis.

Antimicrobial Resistance: The ability of microorganisms to withstand the effects of an antimicrobial agent that once could successfully treat the infection.