massilioclostridium massilioclostridium massilioclostridium is a gram-positive, strict anaerobic, non-spore-forming and non-motile bacterial genus from the family of clostridiaceae with one known species (massilioclostridium coli). massilioclostridium coli has been isolated from the left colon of a patient. massilioclostridium scientific classification domain: bacteria phylum: bacillota class: clostridia order: clostridiales family: clostridiaceae genus: massilioclostridiumlo et al. 2017 species m. coli