Enhancement of UDPgalactose: glycoprotein galactosyltransferase in cultured human skin fibroblasts by cationic polypeptides.
UDPgalactose : glycoprotein galactosyltransferase in normal human skin fibroblast homogenates has been assayed using ovalbumin as an acceptor. The activity in the homogenate fraction sedimenting between 51 300 X g and 105 000 X g was enhanced by the addition of a number of catonic polypeptides of L-configuration but not by those of D-configuration. In contrast to the enhancing effect of poly(L-lysine), poly(L-glutamic acid) inhibited the activity. Poly(D-glutamic acid) had no effect. Cationic or anionic amino acid derivatives, spermine or spermidine had no effect on activity. The enhancement of transferase activity by poly(L-arginine) is probably due to an increase in V for UDPgalactose and ovalbumin. The implication of these results for the regulation of glycoprotein synthesis in cultivated skin fibroblasts and for the pathogenesis of cystic fibrosis is discussed.
D002478:Cells, Cultured; D004789:Enzyme Activation / Q000187:drug effects; D005347:Fibroblasts / Q000201:enzymology; D005700:Galactosyltransferases / Q000378:metabolism*; D005971:Glutamates / Q000494:pharmacology; D006801:Humans; D010455:Peptides / Q000494:pharmacology*; D011107:Polylysine / Q000494:pharmacology; D012867:Skin / Q000187:drug effects / Q000201:enzymology*; D013329:Structure-Activity Relationship
D005971:Glutamates; D010455:Peptides; D011107:Polylysine; D005700:Galactosyltransferases