acetobacter fabarum acetobacter fabarum acetobacter fabarum is a bacterium that was first identified from fermenting cocoa beans in ghana. acetobacter fabarum scientific classification domain: bacteria phylum: pseudomonadota class: alphaproteobacteria order: rhodospirillales family: acetobacteraceae genus: acetobacter species: a. fabarum binomial name acetobacter fabarumcleenwerck, et al. 2008 type strain lmg 24244t (= dsm 19596t) description a. fabarum are gram-negative bacteria that appear as rounded rods, approximately 0.8 micrometers by 1.2 to 3 micrometers in size. if grown on agar plates, a. fabarum forms beige, round colonies that grow to 0.8 millimeters after three days at 28°c.