Glycoproteins of the Lens in Relation to Age and Cataract Formation. Iii. Differences in Composition and Distribution of the Carbohydrate of Glycoprotein of Lens Fibers in Different Regions of the Lens.

t has been reported in the two preceding communications of this series' • that the decapsulated lens of beef and rabbit contain significant amounts of a glycoprotein fraction with a glycan, which essentially consists of galactose, some mannose, glucosamine, fucose, and derivatives of neuraminic acid. In fractionation by centrifugation, this glycoprotein could be sedimented with the albuminoid. It had been pointed out that this glycoprotein material does not form a prosthetic group with the albuminoid itself, as the ratio of carbohydrate to albuminoid varied significantly at different ages of the animal. This ratio in the