What organism is known for having a waxy outer coating?

Mycobacterium is the organism known for having a distinctive waxy outer coating, which is primarily due to the presence of mycolic acids in its cell wall. This waxy layer gives Mycobacterium its characteristic resilience to desiccation (drying out) and allows it to survive in harsh environmental conditions. It also contributes to the bacterium's overall virulence and ability to evade the host's immune responses.

The waxy coat is significant in clinical microbiology, as it makes the organism resistant to many common disinfectants and antibiotics. This feature is particularly notable in Mycobacterium tuberculosis, the causative agent of tuberculosis, where the waxy exterior contributes to its pathogenicity and complicates treatment efforts.

In contrast, other organisms listed do not possess this unique waxy structure, making Mycobacterium stand out for its unique adaptations and clinical implications.