Probably a minor component of the bacterial microcompartment (BMC) shell dedicated to ethanolamine degradation. It might bind nucleic acids. Amine and polyamine degradation; ethanolamine degradation. Monomeric in solution. Belongs to the bacterial microcompartments protein family. In strain MG1655 the eut operon is interrupted by the CPZ-55 prophage, encoding 9 genes situated between eutA and eutB, which are translated in the other direction. CPZ-55 may prevent expression of the eut operon in strain MG1655. Strain W3110 does not have this prophage element and should be able to express the operon.