mycobacterium gilvum mycobacterium gilvum mycobacterium gilvum is a species of the phylum actinomycetota (gram-positive bacteria with high guanine and cytosine content, one of the dominant phyla of all bacteria), belonging to the genus mycobacterium. mycobacterium gilvum scientific classification domain: bacteria phylum: actinomycetota class: actinomycetia order: mycobacteriales family: mycobacteriaceae genus: mycobacterium species: m. gilvum binomial name mycobacterium gilvumstanford and gunthorpe 1971, atcc 43909 etymology: gilvum, latin for pale yellow. description pleomorphic gram-positive, nonmotile and acid-fast rods. colony characteristics pale yellow, scotochromogenic, and smooth pleomorphic colonies. physiology rapid growth on löwenstein-jensen medium at 25 °c and 37 °c, but not at 45 °c, within 7 days. resistant to isoniazid, rifampicin, and sodium aminosalicylate. differential characteristics 5 species-specific antigens, demonstrable in immunodiffusion tests. pathogenesis not assumed to be pathogenic. biosafety level 1 type strain first isolated from sputum and pleura fluid (london). strain atcc 43909 = ccug 37676 = cip 106743 = dsm 44503 = jcm 6395 = nctc 10742.