This family is the short dimerisation domain of the enzyme D-ornithine 4,5-aminomutase. It sits between the TIM-barrel Pfam:PF09043 and Pfam:PF02310. The enzyme is an alpha2-beta2-heterodimer that converts D-ornithine to 2,4-diaminopentanoic acid by way of radical propagation from an adenosylcobalamin to a pyridoxal 5'-phosphate cofactor [1].

1: Large-scale domain dynamics and adenosylcobalamin reorientation orchestrate radical catalysis in ornithine 4,5-aminomutase. Wolthers KR, Levy C, Scrutton NS, Leys D; J Biol Chem. 2010;285:13942-13950. PMID:20106986