Enhancement of UDP-galactose:Mucin galactosyltransferase activity by spermine

摘要: Abstract A microsomal preparation prepared from the mucosal lining of canine trachea catalyzed transfer galactose its uridine diphosphate derivative to sialidase-treated ovine submaxillary mucin. Maximal incorporation occurred at 30 m n 2+ . When concentration in reaction mixture was reduced 2.5 , approximately two-thirds enzymatic activity lost, but full could be restored by addition 1 spermine. Under these conditions spermine did not affect K for UDP-galactose, lowered mucin and Mn a factor 10. The effect abolished with increasing concentrations absence metal, lost Spermidine also stimulated low levels lesser degree than slight stimulatory consistently derived putrescine as well, while cadaverine, putreanine, monoamines were ineffectual. Spermine had similar on GalNAc protein core acceptor little or no sialic acid mucin, N -acetylglucosamine, fucose sialidase-galactosidase-treated fetuin. Similar results obtained enzyme preparations glands. Other polycationic compounds such protamine, histone, polylysine suboptimal