Immediately after the entire precursor, Glc3Man9(GlcNAc)2 is transferred to a nascent polypeptide, three different enzymes, called  glycosidases, remove all three glucose residues and one particular mannose residue.

TLS Online TPP Program

#Id: 7961

#XL - Q Biochemistry

Quantity of free BiP in the ER lumen determines the relative proportions of monomeric and dimeric Ire1.

TLS Online TPP Program

#Id: 7959

#XL - Q Biochemistry

Unfolded-protein response

Key protein –Ire1 promotes formation of Hac1

TLS Online TPP Program

#Id: 7958

#XL - Q Biochemistry

The efficient formation of disulfide bonds in the lumen of the ER depends on the enzyme protein disulfide isomerase (PDI), which is present in all eukaryotic cells

TLS Online TPP Program

#Id: 7956

#XL - Q Biochemistry

A branched oligosaccharide containing 

3 glucose (Glc)

9 mannose (Man)

2 N-acetylglucosamine (GlcNAc)

Glc3Man9(GlcNAc)2

TLS Online TPP Program

#Id: 7955

#XL - Q Biochemistry

Only asparagine residues in the tripeptide sequences Asn-X-Ser and Asn-X-Thr (where X is any amino acid except proline) are substrates for oligosaccharyl transferase.

TLS Online TPP Program

#Id: 7954

#XL - Q Biochemistry

The precursor oligosaccharide is transferred from a

dolichol lipid anchor to the asparagine as an intact unit in a reaction catalyzed by a transmembrane oligosaccharyl transferase enzyme complex.