Characterization and determination of human urinary keratan sulfate.

Keratan sulfate was isolated from normal human urine and was characterized by sugar compositional analysis and H-NMR spectroscopy. It was found that KS from human urine is classified as skeletal type (KS-II type chain) with an O-glycosidic linkage between galactosamine and serine (or threonine). H-NMR studies revealed that urinary KS is not a proteoglycan but a polysaccharide (molecular weight is about 5 kDa). The quantitation of human urinary KS by HPLC showed that urinary KS is excreted at constant levels (0.07 +/- 0.015 microgram/mg creatinine).