This family includes the 5-keto 4-deoxyuronate isomerase enzyme EC:18.104.22.168 that is involved in pectin degradation. This family aldo includes bacterial Myo-inositol catabolism (IolB) proteins. The Bacillus subtilis inositol operon (iolABCDEFGHIJ) is involved in myo-inositol catabolism. Glucose repression of the iol operon induced by inositol is exerted through catabolite repression mediated by CcpA and the iol induction system mediated by IolR. The exact function of IolB is unknown. Members of this family possess a Cupin like structure.