S. flexneri serotype Y O-polysaccharide (O factor 9-positive)
s. flexneri serotype y o-polysaccharide (o factor 9-positive)
A polysaccharide derivative comprised of a [2)-α-<small>L</small>-Rha<em>p</em><small><sup>III</small></sup>-(1→2)-α-<small>L</small>-Rha<em>p</em><small><sup>II</small></sup>-(1→3)-α-<small>L</small>-Rha<em>p</em><small><sup>I</small></sup>-(1→3)-β-<small>D</small>-Glc<em>p</em>NAc-(1→] tetrasaccharide repeat modified by addition of acetyl groups to 40% of the O-6 positions of the GlcNAc residue and to either O-3 or O-4 of many of the Rha<small><sup>III</small></sup> residues (30% to O-3; 20% to O-4). The structure provided is representative of that in <em>Shigella flexneri</em> serotype Y and shows the most common repeating unit.