Biosynthesis of acid mucopolysaccharides by the surviving new born rat skin. I. - Kinetics of the biosynthesis at the polymer level.
1) The amounts of individual mucopolysaccharides in the new born rat skin have been estimated and their specific rates of labelling assessed in vitro. Total and percentage amounts of these polymers agree satisfactorily with previously published data. 2) Relative rates of labelling from [U14C]-glucose have been estimated by combining column chromatography separation and electrophoresis on cellulose acetate strips. Specific radioactivities have been measured either with respect to the total uronic acid content of the fractions or with respect to their quantitative staining with Alcian Blue. The two methods agreed satisfactorily. 3) Average biosynthetic rates almost identical for hyaluronic acid and the total sulfated mucopolysaccharides. However, within the latter fraction, heparin + heparan sulfate incorporate [U14C]-glucose about 4 to 5 times more rapidly than the chondroitin sulfates. This result could not be expected from previous data obtained in vivo and is discussed with reference to a possible heterogeneity of the cell material whence the various mucopolysaccharides originate. 4) In the presence of puromycin, labelling of the sulfated mucopolysaccharides stops almost immediately, indicating a stringent requirement for protein primers. Biosynthesis of hyaluronic acid is affected only after preincubation of tissue with puromycin (one hour) and subsequent incubation of two hours with [U14C]-glucose.
D000818:Animals; D000831:Animals, Newborn; D005947:Glucose / Q000378:metabolism; D006025:Glycosaminoglycans / Q000096:biosynthesis*; D006493:Heparin / Q000096:biosynthesis; D006497:Heparan Sulfate / Q000096:biosynthesis; D006820:Hyaluronic Acid / Q000096:biosynthesis; D007700:Kinetics; D046911:Macromolecular Substances; D011691:Puromycin / Q000494:pharmacology; D051381:Rats; D012867:Skin / Q000187:drug effects / Q000378:metabolism*
D005947:Glucose; D006025:Glycosaminoglycans; D006493:Heparin; D006497:Heparan Sulfate; D006820:Hyaluronic Acid; D046911:Macromolecular Substances; D011691:Puromycin