A.cet.an.ae.ro.bac.te'ri.um. L. neut. n. acetum vinegar; Gr. pref. an not; Gr. n. aer air; anaero not (living) in air; Gr. neut. dim. n. bakterion small rod; N.L. neut. n. Acetanaerobacterium vinegar-producing anaerobic small rod.

Firmicutes / “Clostridia” / Clostridiales / “Ruminococcaceae” / Acetanaerobacterium

Straight, thin rod-shaped cells. 0.2–0.4 × 4–8 µm. Gram-stain-positive. Motile. Nonspore-forming. Obligately anaerobic. No microaerophilic or aerobic growth occurs. Mesophilic; grows at 20–42°C. Grows at neutral pH. Chemo-organotrophic. Oxidase and catalase are not produced. Amino acids and peptides may serve as nitrogen sources. A variety of mono-, di-, and oligosaccharides are fermented. Gelatin and esculin are hydrolyzed. The major fermentation products from glucose include acetate, ethanol, hydrogen, and carbon dioxide; lactic acid, propionate, and succinate are not produced. Sulfate is not reduced. 16S rRNA sequence analysis indicates this genus belonging to the Clostridium leptum rRNA subgroup (Collins et al., 1994) within the family Clostridiaceae. Isolated from the anaerobic sludge of paper mill waste water.

DNA G+C content (mol%): 48.6–50.4.

Type species: Acetanaerobacterium elongatum Chen and Dong 2004, 2261^VP.