mycobacterium confluentis mycobacterium confluentis mycobacterium confluentis is a non-pathogenic bacterium of the oral cavity. mycobacterium confluentis scientific classification domain: bacteria phylum: actinomycetota class: actinomycetia order: mycobacteriales family: mycobacteriaceae genus: mycobacterium species: m. confluentis binomial name mycobacterium confluentiskirschner et al. 1992, atcc 49920 description gram-positive, nonmotile, acid-fast coccobacillus (0.5-0.8 µm x 0.7-1.7 µm), does not form spores, capsules or aerial hyphae. physiology rapid growth within 2 to 4 days on löwenstein-jensen media at 22 °c, 31 °c, 37 °c and 41 °c (optimum growth between 31 °c and 37 °c). in vitro susceptibility to isoniazid, ethambutol and streptomycin. differential characteristics differentiation from other thermotolerant mycobacteria by its inability to grow at temperatures of more than 41 °c. separation from other rapidly growing mycobacteria by its susceptibility to antituberculotic drugs. differentiated from the phenotypic closely related m. thermoresistibile by its inability to grow at 52 °c. pathogenesis not associated with disease. biosafety level 1. type strain first isolated from sputum, koblenz, germany. strain 1389/90 = atcc 49920 = cip 105510 = dsm 44017 = jcm 13671.