pubmed-article:335938 | pubmed:abstractText | The Tween opacity test can be used to differentiate (1) Mycobacterium flavescens from Mycobacterium gordonae and Mycobacterium szulgai, and (2) nonphotochromogenic strains of Mycobacterium kansaii from strains of the Mycobacterium terrae complex. | lld:pubmed |