View the latest EBI news stories and important announcements...

Search The CSA
EC Number

Catalytic Site Atlas

CSA LITERATURE entry for 1foa

E.C. namealpha-1,3-mannosyl-glycoprotein 2-beta-N-acetylglucosaminyltransferase
SpeciesOryctolagus cuniculus (Rabbit)
E.C. Number (IntEnz)
CSA Homologues of 1foa1fo8,1fo9,2am3,2am4,2am5,2apc,
CSA Entries With UniProtID P27115
CSA Entries With EC Number
PDBe Entry 1foa
PDBSum Entry 1foa
MACiE Entry 1foa

Literature Report

IntroductionN-acetylglucosaminyltransferase I (GnT I) is from Oryctolagus cuniculus. It catalyses the attachment of N-acetyl glucosamine (GlcNAc) onto an oligomannose core, from UPD-N-acetyl glucosamine. It plays a critical role in mammalian development.
Mechansim1. Asp 291 acts as a general base to deprotonate a hydroxyl group of the oligomannose core sugar. 2. The deprotonated oxygen atom then acts as a nucleophile and attacks C1 of UPD-N-acetyl glucosamine. 3. The transition state is thought to be oxocarbenium ion-like. 4. The C1 - UPD bond is broken, leaving the n-acetyl glucosamine bonded to the oligomannose core. 5. Mn2+ stabilises the build up of negative charge on the beta-phosphate of the UPD. 6. It is thought that Asp 291 then acts as an acid to protonate the UPD leaving group.

Catalytic Sites for 1foa

Annotated By Reference To The Literature - Site 1 (Perform Site Search)
ResidueChainNumberUniProtKB NumberFunctional PartFunctionTargetDescription
AspA291291macie:sideChainAsp 291 acts as a general base by accepting a proton from a hydroxyl group on the oligamannose core. It must then donate that proton back to the leaving group UPD phosphate ion.

Literature References

Unligil UM
X-ray crystal structure of rabbit N-acetylglucosaminyltransferase I: catalytic mechanism and a new protein superfamily.
EMBO J 2000 19 5269-5280
PubMed: 11032794