Spontaneous galactosylation of agalactoglycoproteins in colostrum.
We have found that spontaneous galactosylation of GlcNAc residues occurs in bovine colostrum, but not in dialyzed colostrum, without adding UDP-Gal as a donor substrate. UDP-Gal was shown to be present in bovine colostrum at a level ranging from 200 to 600 microM. When a tracer UDP-[(14)C]Gal was added to the dialyzed colostrum together with a Gal beta1,4-specific beta-galactosidase, remarkable incorporation of radioactivity into 24-28 kDa and 33 kDa RCA1-positive glycoproteins was demonstrated by SDS-PAGE/autoradiography. Some 100-140 kDa agalactoglycoproteins of a CHO mutant cell line were also galactosylated on a blotted membrane by the incubation in the colostrum.
Oubihi
M
M
Department of Applied Molecular Biosciences, Graduate School of Bioagricultural Sciences, Nagoya University, Chikusa-ku, Nagoya, Japan.
Kitajima
K
K
Aoki
N
N
Matsuda
T
T
D000818:Animals; D016466:CHO Cells; D002417:Cattle; D002474:Cell-Free System / Q000378:metabolism; D003126:Colostrum / Q000378:metabolism*; D006224:Cricetinae; D005260:Female; D005690:Galactose / Q000378:metabolism*; D006023:Glycoproteins / Q000737:chemistry / Q000378:metabolism*; D007700:Kinetics; D007768:Lactalbumin / Q000378:metabolism; D008970:Molecular Weight; D009237:N-Acetyllactosamine Synthase / Q000378:metabolism; D011247:Pregnancy; D013379:Substrate Specificity; D014531:Uridine Diphosphate Galactose / Q000378:metabolism; D001616:beta-Galactosidase / Q000378:metabolism
D006023:Glycoproteins; D014531:Uridine Diphosphate Galactose; D007768:Lactalbumin; D009237:N-Acetyllactosamine Synthase; D001616:beta-Galactosidase; D005690:Galactose