Comments: |
Unlike heteropolymeric O antigens, which are polymerized in the periplasm by EC 2.4.99.27, O antigen polymerase Wzy, homopolymeric O antigens are polymerized inside the cytoplasm by a progressive transfer of sugar monomers to a growing chain attached to a polyprenyl diphosphate membrane anchor. When the chain reaches its full length it is transported across the cytoplasmic membrane by this ABC-type transporter, which consists of an ATP-binding subunit (Wzt) and an integral membrane protein (Wzm). Wzm proteins are poorly conserved in their primary sequence. Once in the periplasm, the O antigen is ligated to the lipid A-core complex by EC 2.4.99.26, O-antigen ligase. |
References: |
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