9.B.128 The O-antigen Polymerase, WzyE (WzyE) Family
The WzyX translocase (2.A.66.2.12) (an isoprenoid lipid sugar glucan flippase) forms a complex with Wzy (WzyE) and Wzz for assembly of periplasmic O-antigen in lipopolysaccharide (Marolda et al., 2006). WzyE (450aas; 11-13 TMSs) is referred to as the enterobacterial common antigen (ECA) polysaccharide chain elongation polymerase (Kajimura et al., 2005). However, it and its homologues 'look like' a permease and show appreciable sequence similarity with MFS and MATE carriers following TC BLAST searches. This family may be distantly related to 9.B.67, also designated as an O-antigen polymerase family.