Comparative NMR analysis of reduced CS hexamers from ABC lyase (A,C), and hyaluronidase (B,D) digestions using 1H-15N gHSQC spectra. (A) C666S-ol, (B) ΔC664S-ol, (C) ΔC644S-ol, and (D) C444-ol. The peaks assigned as 6Snon-red., and 4S-ol belong to the 6-sulfated and 4-sulfated GalNAc units from non-reducing and reduced terminals respectively.