Probably forms vertices in the bacterial microcompartment (BMC) shell dedicated to ethanolamine degradation. Expression of eutK, eutL, eutM, eutN, eutS (eutSMNLK) in E.coli leads to formation of a single BMC (PubMed:22428024, PubMed:27063436). Coexpression of eutQ with eutSMNLK permits E.coli to make cells with more than one mobile BMC, as is usual in vivo (PubMed:27063436). It may be involved in transporting positively charged molecules into and out of the BMC (By similarity). The ethanolamine (EA) catabolic bacterial microcompartment (BMC) probably concentrates low levels of ethanolamine catabolic enzymes, concentrates volatile reaction intermediates, keeps the level of toxic acetaldehyde low, generates enough acetyl-CoA to support cell growth, and maintains a pool of free coenzyme A (CoA) and NAD. 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 (EAL) activity and to induce the operon (PubMed:3045078). EA enhances bacterial survival in macrophages in a concentration-dependent manner, suggesting it is an important nutrient during infection (PubMed:29531136). Amine and polyamine degradation; ethanolamine degradation. Homopentamer with a small central pore. Part of the 17-gene eut operon transcribed from a single promoter, induced by ethanolamine and adenosylcobalamin (AdoCbl, vitamin B12). A double eutM-eutN strain grows as well as wild-type on ethanolamine (EA) and cyanocobalamin, but a quadruple eutL-eutK-eutM-eutN strain does not grow (PubMed:16291677). A non-polar deletion mutant grows on EA at pH 5.5 to pH 7.0 but not at pH 8.0 or pH 8.5, releases increased amounts of acetaldehyde on EA plus vitamin B12. Preventing acetaldehyde vapor loss allow growth up to pH 8.5 (PubMed:16585748). Artificial BMCs can be made in E.coli by expressing eutK, eutL, eutM, eutN, eutS (eutSMNLK) or eutS alone. Cargo proteins can be targeted to them and beta-galactosidase (lacZ) was active within the BMC, showing the BMC allows passage of substrate into the interior. This can lead to the development of tailored BMCs for specific metabolic reactions (PubMed:22428024). The addition of eutQ to the eutSMNLK construct results in biogenesis of multiple BMCs (PubMed:27063436). The need for a bacterial microcompartment in EA metabolism can be bypassed by increasing the levels of EAL and an acetaldehyde dehydrogenase (not necessarily EutE). Belongs to the CcmL/EutN family.