This family consists of examples of ADP-L-glycero-D-mannoheptose-6-epimerase, an enzyme involved in biosynthesis of the inner core of lipopolysaccharide (LPS) for Gram-negative bacteria. This enzyme is homologous to UDP-glucose 4-epimerase (TIGR01179) and belongs to the NAD dependent epimerase/dehydratase family (pfam01370). [Cell envelope, Biosynthesis and degradation of surface polysaccharides and lipopolysaccharides]