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Crystal structures of Toxoplasma gondii HGXPRTase reveal the catalytic role of a long flexible loop.

Publication ,  Journal Article
Schumacher, MA; Carter, D; Roos, DS; Ullman, B; Brennan, RG
Published in: Nat Struct Biol
October 1996
Published version (DOI) Link to item

Crystal structures of substrate-free and XMP-soaked hypoxanthine-guanine-xanthine phosphoribosyltransferase (HGXPRTase) of the opportunistic pathogen Toxoplasma gondii have been determined to 2.4 and 2.9 A resolution, respectively. HGXPRTase displays the conserved PRTase fold. In the structure of the enzyme bound to its product, a long flexible loop (residues 115-126) is located away from the active site. Comparison to the substrate-free structure reveals a striking relocation of the loop, which is poised to cover the catalytic pocket, thus providing a mechanism by which the HG(X)PRTases shield their oxocarbonium transition states from nucleophilic attack by the bulk solvent. The conserved Ser 117-Tyr 118 dipeptide within the loop is brought to the active site, completing the ensemble of catalytic residues.

Duke Scholars

Maria Anne Schumacher
Author Maria Anne Schumacher Biochemistry
Richard Gerald Brennan
Author Richard Gerald Brennan Biochemistry

Published In

Nat Struct Biol

DOI

10.1038/nsb1096-881

ISSN

1072-8368

Publication Date

October 1996

Volume

3

Issue

10

Start / End Page

881 / 887

Location

United States

Related Subject Headings

  • Toxoplasma
  • Substrate Specificity
  • Protein Conformation
  • Pentosyltransferases
  • Developmental Biology
  • Biophysics
  • Binding Sites
  • Animals
  • 34 Chemical sciences
  • 32 Biomedical and clinical sciences
 

Citation

APA
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ICMJE
MLA
NLM
Schumacher, M. A., Carter, D., Roos, D. S., Ullman, B., & Brennan, R. G. (1996). Crystal structures of Toxoplasma gondii HGXPRTase reveal the catalytic role of a long flexible loop. Nat Struct Biol, 3(10), 881–887. https://doi.org/10.1038/nsb1096-881
Schumacher, M. A., D. Carter, D. S. Roos, B. Ullman, and R. G. Brennan. “Crystal structures of Toxoplasma gondii HGXPRTase reveal the catalytic role of a long flexible loop.” Nat Struct Biol 3, no. 10 (October 1996): 881–87. https://doi.org/10.1038/nsb1096-881.
Schumacher MA, Carter D, Roos DS, Ullman B, Brennan RG. Crystal structures of Toxoplasma gondii HGXPRTase reveal the catalytic role of a long flexible loop. Nat Struct Biol. 1996 Oct;3(10):881–7.
Schumacher, M. A., et al. “Crystal structures of Toxoplasma gondii HGXPRTase reveal the catalytic role of a long flexible loop.” Nat Struct Biol, vol. 3, no. 10, Oct. 1996, pp. 881–87. Pubmed, doi:10.1038/nsb1096-881.
Schumacher MA, Carter D, Roos DS, Ullman B, Brennan RG. Crystal structures of Toxoplasma gondii HGXPRTase reveal the catalytic role of a long flexible loop. Nat Struct Biol. 1996 Oct;3(10):881–887.

Published In

Nat Struct Biol

DOI

10.1038/nsb1096-881

ISSN

1072-8368

Publication Date

October 1996

Volume

3

Issue

10

Start / End Page

881 / 887

Location

United States

Related Subject Headings

  • Toxoplasma
  • Substrate Specificity
  • Protein Conformation
  • Pentosyltransferases
  • Developmental Biology
  • Biophysics
  • Binding Sites
  • Animals
  • 34 Chemical sciences
  • 32 Biomedical and clinical sciences