beta-D-GlcpA-(1->3)-beta-L-GalpNAc-(1->4)-beta-D-GlcpA-(1->3)-beta-L-GalpNAc-(1->4)-beta-D-GlcpA-(1->3)-beta-L-Galp-(1->3)-beta-L-Galp-(1->4)-?-D-Xylp(1->