mycoplasma

Mycoplasma is a group of extremely small bacteria that do not have a cell wall. Most bacteria depend on this outer layer for shape and protection, but mycoplasmas live without it. That makes them small, flexible, and harder to treat with antibiotics such as penicillin, which work by attacking bacterial cell walls.

The name "mycoplasma" comes from Greek words meaning "fungus" and "formed thing." This reflects an early mistake in classification. Because they are tiny and do not have a fixed shape, scientists once confused them with fungi. We now know they are bacteria, but very unusual ones.

These organisms can be found in animals, humans, plants, and the environment. Many are harmless, but some cause disease. For example, Mycoplasma pneumoniae can cause "atypical pneumonia," which is often milder than typical bacterial pneumonia but may last longer. Other kinds are linked to infections of the urinary or genital tract, and some species affect animals or crops.

Diagnosing these infections can be difficult because mycoplasmas grow slowly and are hard to culture in a lab. Doctors often use tests such as PCR to find their genetic material. Treatment usually requires antibiotics that target other parts of the bacteria, not the cell wall. Mycoplasma reminds us that even very small forms of life can be highly adapted and medically important.