PDBsum entry: 1ecf

Transferase (glutamine amidotransferase)

PDB id: 1ecf

Contents

Protein chains

492 a.a. *

Ligands

PIN ×6

Waters ×986

* Residue conservation analysis

PDB id:

1ecf

Name:

Transferase (glutamine amidotransferase)

Title:

Escherichia coli glutamine phosphoribosylpyrophosphate (prpp amidotransferase

Structure:

Glutamine phosphoribosylpyrophosphate amidotransf chain: a, b. Engineered: yes

Source:

Escherichia coli. Organism_taxid: 562. Cell_line: bl21. Gene: purf. Expressed in: escherichia coli bl21(de3). Expression_system_taxid: 469008. Other_details: t7 phi10 promoter

Biol. unit:

Tetramer (from PDB file)

Resolution:

2.00Å R-factor: 0.175 R-free: 0.230

Authors:

J.M.Krahn

Key ref:

C.R.Muchmore et al. (1998). Crystal structure of glutamine phosphoribosylpyrophosphate amidotransferase from Escherichia coli. Protein Sci, 7, 39-51. PubMed id: 9514258 Ref: Full text

Date:

23-Apr-96 Release date: 08-Nov-96

Protein chains

P0AG16  (PUR1_ECOLI) -  Amidophosphoribosyltransferase

Seq: 505 a.a.

Struc: 492 a.a.

Enzyme reactions

• Enzyme class: E.C.2.4.2.14 - Amidophosphoribosyltransferase.
• Reaction: 5-phospho-beta-D-ribosylamine + diphosphate + L-glutamate = L-glutamine + 5-phospho-alpha-D-ribose 1-diphosphate + H₂O

Molecule diagrams generated from .mol files obtained from the KEGG ftp site

 Gene Ontology (GO) functional annotation 

• Cellular component: cytoplasm (2 terms)
• Biological process: metabolic process (5 terms)
• Biochemical function: transferase activity (4 terms)

reference

Full text	Protein Sci 7:39-51 (1998)
PubMed id: 9514258

Crystal structure of glutamine phosphoribosylpyrophosphate amidotransferase from Escherichia coli.

C.R.Muchmore, J.M.Krahn, J.H.Kim, H.Zalkin, J.L.Smith.

ABSTRACT

Crystal structures of glutamine phosphoribosylpyrophosphate (PRPP) amidotransferase from Escherichia coli have been determined to 2.0-A resolution in the absence of ligands, and to 2.5-A resolution with the feedback inhibitor AMP bound to the PRPP catalytic site. Glutamine PRPP amidotransferase (GPATase) employs separate catalytic domains to abstract nitrogen from the amide of glutamine and to transfer nitrogen to the acceptor substrate PRPP. The unliganded and AMP-bound structures, which are essentially identical, are interpreted as the inhibited form of the enzyme because the two active sites are disconnected and the PRPP active site is solvent exposed. The structures were compared with a previously reported 3.0-A structure of the homologous Bacillus subtilis enzyme (Smith JL et al., 1994, Science 264:1427-1433). The comparison indicates a pattern of conservation of peptide structures involved with catalysis and variability in enzyme regulatory functions. Control of glutaminase activity, communication between the active sites, and regulation by feedback inhibitors are addressed differently by E. coli and B. subtilis GPATases. The E. coli enzyme is a prototype for the metal-free GPATases, whereas the B. subtilis enzyme represents the metal-containing enzymes. The structure of the E. coli enzyme suggests that a common ancestor of the two enzyme subfamilies may have included an Fe-S cluster.

Selected figure(s)

Figure 1.
Fig. 1. Tetramer of E. coli GPATaseThethreemolecular twofold axes, P, and R, are indicated. Subunlts aredrawn in contrasting colors.

Figure 6.
Fig. 6. Comparison f nucleotidebinding bites n E. ol~ (left)and B. srtbrilis (right) GPATases.View is longthemolccular P axis. heproxim~ty fthe C andAsites is learfromthisdiagram. as is theparticipation of thehase-bindingpeptide ~n twoAsites.Residues discuxscd in thetext are laheled.TheAMP~noleculesaredrawn In whitebonds.andpeptidesfromdifferentsubunits in contrasting colors.

The above figures are reprinted from an Open Access publication published by the Protein Society: Protein Sci (1998, 7, 39-51) copyright 1998.

Figures were selected by an automated process.