Bacteria without plasmid
You might want to take a look at Bacillus subtilis. Most of the lab strains don't contain plasmids, though they have been found in some environmental isolates. 

https://academic.oup.com/femsre/article/21/4/337/490925

All this depends on exactly what you're looking for: a species with no known plasmids in any isolates, or some commonly used lab strains with no plasmids? 

M. tb is a pretty unique case. Most of the other species in the Mycobacterium genus do contain plasmids.