Macromolecular architecture and hydrodynamic properties of human cervical mucins

Abstract

Cervical mucus glycoproteins (mucins) were extracted by using slow stirring in 6M-guanidinium chloride supplemented with proteinase inhibitors. Subsequent purification was achieved by isopycnic density-gradient centrifugation in CsCl/guanidinium chloride. The whole mucins (M_r 10 × 10⁶ – 15 × 10⁶) were degraded into ‘subunits’ (M_r 2 × 10⁶ – 3 × 10⁶) by reduction. Trypsin digestion of subunits afforded glycopeptides (‘T-domains’) with M_r 0.4 × 10⁶. The relationship between the intrinsic viscosity and M_r for the whole mucins and the fragments suggests that cervical mucins are linear flexible macromolecules. This view is supported by hydrodynamic data.