Acid-fast staining bacteria?

Question

1.What makes Mycobacterium particularly resistant to staining? How are the bacteria in this genus grouped in terms of Gram classification?

2. How do you think the acid-fast nature of Mycobacterium contributes to its virulence?

Answer 1

Mycobacteria have a large amount of a lipid called mycolic acid in their cell walls that makes them resistant to typical gram staining, and for this reaon are not classified as gram positive or gram negative, but for the record they are weakly gram positive.

The mycolic acid also meakes the bacteria more resistant to disinfectants and some antibiotics.