Intracellular bacteria
Intracellular bacteria are bacteria that have the capability to enter and survive within the cells of the host organism. These bacteria include many different pathogens that live in the cytoplasm and nuclei of the host cell's they inhabit. Mycobacterium tuberculosis is an example of an intracellular bacterial species. There are two types of intracellular bacteria: facultative intracellular bacteria, which can grow extracellularly or intracellularly, and obligate intracellular bacteria, which can grow only intracellularly.