Catalyzes the deamination of various vicinal amino-alcohols to oxo compounds (Probable). It is spontaneously inactivated by its substrate and reactivated by EutA (By similarity). May play a role in BMC assembly or maintenance (Probable). Expression of the eut operon allows this bacteria to use ethanolamine (EA) as a carbon, nitrogen and energy source. It relies on cobalamin (vitamin B12) both as a cofactor for the ethanolamine ammonia-lyase activity and to induce the operon. EA enhances bacterial survival in macrophages in a concentration-dependent manner, suggesting it is an important nutrient during infection (PubMed:29531136). ethanolamine = acetaldehyde + NH4(+) Binds between the large and small subunits. Amine and polyamine degradation; ethanolamine degradation. The basic unit is a heterodimer which dimerizes to form tetramers. The heterotetramers trimerize; 6 large subunits form a core ring with 6 small subunits projecting outwards. Probably located in the BMC; as EutC is targeted to the BMC interior this subunit should be in the same location (Probable). Has been suggested to be on the exterior of the BMC (PubMed:23585538). Part of the 17-gene eut operon transcribed from a single promoter, induced by ethanolamine and adenosylcobalamin (AdoCbl, vitamin B12). No aerobic growth on ethanolamine (EA) supplemented with cobalamin (vitamin B12) (PubMed:10464203, PubMed:2656649). No phenotype during growth in vitro. Decreased expression of eutR during bacterial growth in vitro. About 10-fold outcompeted by wild-type in mouse intestine at 2 and 4 days following oral infection, but no effect seen during growth in peritoneal exudate macrophages (PubMed:26565973). A non-polar deletion mutant does not grow on EA between pH 5.5 and pH 8.5, stops acetaldehyde release on EA plus vitamin B12 (PubMed:16585748). A deletion allows growth on acetate, suggesting BMC assembly or maintenance is impaired (PubMed:23585538). Belongs to the EutB family.