mycobacteria vs true bacteria

mycobacteria and true bacteria both are nouns.

Word	Noun	Adjective	Verb	Adverb
mycobacteria	Yes	No	No	No
true bacteria	Yes	No	No	No

As nouns, true bacteria is a hypernym of mycobacteria; that is, true bacteria is a word with a broader meaning than mycobacteria:

mycobacteria: rod-shaped bacteria some saprophytic or causing diseases
true bacteria: a large group of bacteria having rigid cell walls; motile types have flagella

Other hypernyms of mycobacteria include eubacteria, eubacterium.

mycobacteria (noun)	true bacteria (noun)
rod-shaped bacteria some saprophytic or causing diseases	a large group of bacteria having rigid cell walls; motile types have flagella