Cloned (Comment) | Organism |
---|---|
gene gene TbGT11, DNA and amino acid sequence determination and analysis, gene TbGT11 encodes a Golgi apparatus resident UDP-GlcNAc:alpha3-D-mannoside beta1-2-N-acetylglucosaminyltransferaseI activity (TbGnTI).overexpression of full-length TbGT11 with a C-terminal HA3 epitope tag from a plasmid based on the trypanosome expression vector pLEW82 | Trypanosoma brucei brucei |
Localization | Comment | Organism | GeneOntology No. | Textmining |
---|---|---|---|---|
Golgi apparatus | - |
Trypanosoma brucei brucei | 5794 | - |
Natural Substrates | Organism | Comment (Nat. Sub.) | Natural Products | Comment (Nat. Pro.) | Rev. | Reac. |
---|---|---|---|---|---|---|
UDP-N-acetyl-D-glucosamine + 3-(alpha-D-mannosyl)-beta-D-mannosyl-R | Trypanosoma brucei brucei | - |
UDP + 3-(2-[N-acetyl-beta-D-glucosaminyl]-alpha-D-mannosyl)-beta-D-mannosyl-R | - |
? | |
UDP-N-acetyl-D-glucosamine + 3-(alpha-D-mannosyl)-beta-D-mannosyl-R | Trypanosoma brucei brucei 427 | - |
UDP + 3-(2-[N-acetyl-beta-D-glucosaminyl]-alpha-D-mannosyl)-beta-D-mannosyl-R | - |
? |
Organism | UniProt | Comment | Textmining |
---|---|---|---|
Trypanosoma brucei brucei | - |
expressing VSG variant 221 and transformed to stably express T7 polymerase and the tetracycline repressor protein under G418 antibiotic selection, gene TbGT11 or Tb427.3.5660 | - |
Trypanosoma brucei brucei 427 | - |
expressing VSG variant 221 and transformed to stably express T7 polymerase and the tetracycline repressor protein under G418 antibiotic selection, gene TbGT11 or Tb427.3.5660 | - |
Substrates | Comment Substrates | Organism | Products | Comment (Products) | Rev. | Reac. |
---|---|---|---|---|---|---|
UDP-N-acetyl-D-glucosamine + 3-(alpha-D-mannosyl)-beta-D-mannosyl-R | - |
Trypanosoma brucei brucei | UDP + 3-(2-[N-acetyl-beta-D-glucosaminyl]-alpha-D-mannosyl)-beta-D-mannosyl-R | - |
? | |
UDP-N-acetyl-D-glucosamine + 3-(alpha-D-mannosyl)-beta-D-mannosyl-R | enzyme TbGnTI transfers UDP-GlcNAc to biantennary Man3GlcNAc2, but not to triantennary Man5GlcNAc2, which is the preferred substrate for metazoan enzymes | Trypanosoma brucei brucei | UDP + 3-(2-[N-acetyl-beta-D-glucosaminyl]-alpha-D-mannosyl)-beta-D-mannosyl-R | - |
? | |
UDP-N-acetyl-D-glucosamine + 3-(alpha-D-mannosyl)-beta-D-mannosyl-R | - |
Trypanosoma brucei brucei 427 | UDP + 3-(2-[N-acetyl-beta-D-glucosaminyl]-alpha-D-mannosyl)-beta-D-mannosyl-R | - |
? | |
UDP-N-acetyl-D-glucosamine + 3-(alpha-D-mannosyl)-beta-D-mannosyl-R | enzyme TbGnTI transfers UDP-GlcNAc to biantennary Man3GlcNAc2, but not to triantennary Man5GlcNAc2, which is the preferred substrate for metazoan enzymes | Trypanosoma brucei brucei 427 | UDP + 3-(2-[N-acetyl-beta-D-glucosaminyl]-alpha-D-mannosyl)-beta-D-mannosyl-R | - |
? |
Synonyms | Comment | Organism |
---|---|---|
GnTI | - |
Trypanosoma brucei brucei |
TbGnTI | - |
Trypanosoma brucei brucei |
UDP-GlcNAc:alpha3-D-mannoside beta1-2-N-acetylglucosaminyltransferase I | - |
Trypanosoma brucei brucei |
General Information | Comment | Organism |
---|---|---|
evolution | sequence alignment reveals that the Trypanosoma brucei enzyme is far removed from the metazoan GnTI family and suggests that the parasite has adapted the beta3-glycosyltransferase family to catalyze beta1-2 linkages. It belongs to a family of putative UDP-sugar-dependent glycosyltransferases with similarity to the mammalian beta1-3-glycosyltransferase family. Enzyme TbGnTI transfers UDP-GlcNAc to biantennary Man3GlcNAc2, but not to triantennary Man5GlcNAc2, which is the preferred substrate for metazoan enzymes | Trypanosoma brucei brucei |
malfunction | the bloodstream-form TbGT11 null mutant exhibits significantly modified protein N-glycans but normal growth in vitro and infectivity to rodents | Trypanosoma brucei brucei |
metabolism | the first step in hybrid and complex N-glycan biosynthesis is initiated by N-acetylglucosaminyltransferase I (GnTI) through the addition of an N-acetylglucosamine (GlcNAc) residue to the alpha1-3-linked core mannose of Man5GlcNAc2 | Trypanosoma brucei brucei |
physiological function | in contrast to multicellular organisms, where the enzyme activity is essential for biosynthesis of both complex and hybrid N-glycans, Trypanosoma brucei TbGT11 null mutants produce atypical pseudohybrid glycans, indicating that the enzyme activity is not dependent on prior TbGnTI action. The enzyme GnTI reaction is essential for biosynthesis of both complex and hybridN-glycans. TbGnTII activity is not dependent on prior TbGnTI action | Trypanosoma brucei brucei |