MetaCyc Enzyme: glucosamine-1-phosphate guanylyltransferase

Gene: ptmE Accession Number: G-12602 (MetaCyc)

Synonyms: Cj1329

Species: Campylobacter jejuni jejuni NCTC 11168 = ATCC 700819

The subunit structure of this enzyme has not been reported.

In the food-borne pathogen Campylobacter jejuni this enzyme participates in the biosynthesis of CMP-N,N'-diacetyllegionaminate (CMP-legionaminic acid), a virulence-associated, cell surface sialic acid-like derivative (see pathway CMP-legionaminate biosynthesis I). PtmE is a nucleotidyltransferase with an absolute specificity for GTP when D-glucosamine 1-phosphate is the substrate. This allowed large-scale purification of GDP-D-glucosamine) [Schoenhofen09].

Recombinant, N-terminal His6-tagged polypeptide was purified and characterized. The ptmE gene sequence contained a CBS domain of unknown function [Schoenhofen09].

In "one pot" enzymatic reactions, PtmF, PtmA, PgmL and PtmE converted β-D-fructofuranose 6-phosphate to GDP-D-glucosamine in the CMP-legionaminic acid biosynthetic pathway. Metabolites were purified and identified by capillary electrophoresis/mass spectrometry analysis and NMR spectroscopy [Schoenhofen09].

Map Position: [1,256,292 -> 1,257,317]

Molecular Weight of Polypeptide: 38.839 kD (from nucleotide sequence)

Unification Links: Entrez-gene:905621 , Protein Model Portal:Q0P8S9 , String:192222.Cj1329 , UniProt:Q0P8S9

Relationship Links: InterPro:IN-FAMILY:IPR000644 , InterPro:IN-FAMILY:IPR005835 , InterPro:IN-FAMILY:IPR029044 , Pfam:IN-FAMILY:PF00483 , Pfam:IN-FAMILY:PF00571 , Prosite:IN-FAMILY:PS51371 , Smart:IN-FAMILY:SM00116

Gene-Reaction Schematic: ?

Gene-Reaction Schematic

Created 15-Mar-2011 by Fulcher CA , SRI International

Enzymatic reaction of: glucosamine-1-phosphate guanylyltransferase

EC Number: 2.7.7.-

D-glucosamine 1-phosphate + GTP + H+ <=> GDP-D-glucosamine + diphosphate

The reaction direction shown, that is, A + B ↔ C + D versus C + D ↔ A + B, is in accordance with the direction in which it was curated.

The reaction is favored in the direction shown.

Alternative Substrates for D-glucosamine 1-phosphate: α-D-glucopyranose 1-phosphate [Schoenhofen09 ] , N-acetyl-α-D-glucosamine 1-phosphate [Schoenhofen09 ]

In Pathways: CMP-legionaminate biosynthesis I

This nucleotidyltransferase showed an absolute specificity for GTP as donor when D-glucosamine 1-phosphate was used as acceptor. The enzyme was specific for the C4 configuration of D-glucose. galactosamine-1-phosphate was not a substrate. When N-acetyl-α-D-glucosamine 1-phosphate was used as acceptor, the enzyme showed more promiscuity with regard to NTP donors [Schoenhofen09].


Schoenhofen09: Schoenhofen IC, Vinogradov E, Whitfield DM, Brisson JR, Logan SM (2009). "The CMP-legionaminic acid pathway in Campylobacter: biosynthesis involving novel GDP-linked precursors." Glycobiology 19(7);715-25. PMID: 19282391

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Please cite the following article in publications resulting from the use of MetaCyc: Caspi et al, Nucleic Acids Research 42:D459-D471 2014
Page generated by SRI International Pathway Tools version 19.0 on Sat Oct 10, 2015, biocyc13.