Conversion of 14C-galactose into amino acids in tissue culture cells and its inhibition by manganese.
The incorporation of 14C-galactose into primary AGMK-cells was studied in the presence and absence of Mn2+. The transport of galactose into the cells is not influenced by Mn2+. 1 mM MnCl2 inhibits the incorporation of galactose into acid-precipitable material up to 50% after 6 hours incubation. In the absence of Mn2+ a substantial amount of galactose is converted to glucose, which is mainly metabolized into aspartic acid and serine. The conversion of galactose into glucose is inhibited by the addition of Mn2+. However, Mn2+ does not influence the activity of the UDP-galactose-4'-epimerase in vitro. Using the SDS-polyacrylamide electrophoresis the labelling of protein bands is similar with 14C-galactose or a 14C-amino acid mixture, respectively. In the presence of Mn2+ the incorporation of both galactose or amino acids is inhibited: With amino acids the inhibition is observed in all protein bands, whereas with galactose some bands remain unaffected. It is concluded that these are galactoproteins.
D000596:Amino Acids / Q000096:biosynthesis*; D000818:Animals; D002118:Calcium / Q000494:pharmacology; D002478:Cells, Cultured; D005690:Galactose / Q000378:metabolism*; D006023:Glycoproteins / Q000096:biosynthesis*; D000882:Haplorhini; D008274:Magnesium / Q000494:pharmacology; D008345:Manganese / Q000494:pharmacology*; D014531:Uridine Diphosphate Galactose / Q000378:metabolism; D014532:Uridine Diphosphate Glucose / Q000378:metabolism
D000596:Amino Acids; D006023:Glycoproteins; D014531:Uridine Diphosphate Galactose; D008345:Manganese; D008274:Magnesium; D002118:Calcium; D014532:Uridine Diphosphate Glucose; D005690:Galactose