Golgi Galactosyl transferase

Fig. 3. Representative pathway for the biosynthesis of Asn-linked oligosaccharide. Biosynthesis starts in the rough endoplasmic reticulum and proceeds through the cis-, medial-, and trans-Golgi apparatus, before glycoprotein is secreted. Some of the enzymes involved are oligosaccharyl transferase (OST) a-glucosidase I II (aG I II) ER-mannosidase (aM) a-mannosidase I II (aM I II) N-acetylglucosaminyl transferase I II (GnT I II) fucosyl transferase (FucT) galactosyl transferase (GalT) sialyl transferase (ST). n-Gn O-Man -Glc V-Fuc A-Gal O-SA (adopted from [40])...

Since the PSV may be a tubular network rather than a series of distinct vesicles, secretion of the components may not require extensive vesicle fusion with the plasma membrane. Secretion parallels loss of UDP-Gal polysaccharide galactosyl transferase that is localized in the Golgi [189,190] suggesting that multiple secretory pathways may be coordinated to form the spore coat. 

Membrane enzymes enzymes present on the surfaces or integrated into the phospholipid bilayer of the many different types of Biomembranes (see), e.g. glucose 6-phosphatase of the endoplasmic reticulum, galactosyl transferase of the Golgi apparatus, oli-gomycin-sensitive ATPase of the inner mitochondrial membrane, monoamine oxidase and rotenone-insen-sitive NADH-cytochrome c-reductase of the outer mitochondrial membrane, and the sodium-independent ATPase and 5 -nueleotidase of the cell membrane. Very many reactions occur on membranes, and M.e. play a central part in cell metabolism. M.e. are useful as markers in the isolation and identifica-... 

Giraudo, CG, Daniotti, JL and Maccioni, HJF (2001) Physical and functional association of glycolipid N-acetyl-galactosaminyl and galactosyl transferases in the Golgi apparatus. Proc Natl Acad Sci USA, 98, 1625-1630. 

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