Mycoplasma pneumoniae is a type of bacteria that causes respiratory infections, particularly pneumonia. It is unique because it lacks a cell wall, making it different from many other bacteria. This characteristic allows it to change shape and evade certain antibiotics that target cell wall synthesis. Infections caused by Mycoplasma pneumoniae are often mild and can spread through respiratory droplets. Symptoms may include a persistent cough, fever, and fatigue. It is most common in children and young adults, especially in crowded environments like schools and military barracks.