Name the pathogen responsible for causing tuberculosis.

Mycobacterium tuberculosis is the bacterium that causes tuberculosis, a significant infectious disease that primarily affects the lungs but can also affect other parts of the body. It is an acid-fast bacillus that exhibits a unique thick lipid-rich cell wall, making it resistant to many standard disinfectants and contributing to its virulence.

Understanding the nature of Mycobacterium tuberculosis is crucial for recognizing how it evades the immune system and persists in the host. The bacterium's transmission occurs primarily through airborne particles when an infected person coughs, sneezes, or speaks, highlighting the importance of public health measures in controlling outbreaks.

In contrast, Escherichia coli, Staphylococcus aureus, and Streptococcus pneumoniae are associated with different infections. E. coli is commonly known for causing gastrointestinal disturbances and urinary tract infections, while Staphylococcus aureus is notorious for skin infections and more serious conditions like pneumonia and sepsis. Streptococcus pneumoniae is well recognized for causing pneumonia, meningitis, and otitis media. Each of these pathogens affects different systems and presents in distinct clinical contexts, underscoring the specificity required in microbiological diagnostics and treatment strategies.