Acetonema is a genus of bacteria in the family Veillonellaceae. It is H2-oxidizing CO2-reducing acetogenic strictly anaerobicendospore-forming Gram-negative motile rod-shaped, isolated from gut contents of the wood-feeding termitePterotermes occidentis. Cells are catalase positive, oxidase negative, and have 51.5 mol percent G + C in their DNA. Optimum conditions for growth on H2 + CO2 are at 30โ33 degrees C and pH (initial) 7.8. Acetonema longum is the sole species within the genus.[2]