Phosphate closes the solution structure of the 5-enolpyruvylshikimate-3-phosphate synthase (EPSPS) from Mycobacterium tuberculosis.

Abstract

The 5-enolpyruvylshikimate-3-phosphate synthase catalyses the sixth step of the shikimate pathway that is responsible for synthesizing aromatic compounds and is absent in mammals, which makes it a potential target for drugs development against microbial diseases. Here, we report the phosphate binding effects at the structure of the 5-enolpyruvylshikimate-3-phosphate synthase from Mycobacterium tuberculosis. This enzyme is formed by two similar domains that close on each other induced by ligand binding, showing the occurrence of a large conformation change. We have monitored the phosphate binding effects using analytical ultracentrifugation, small angle X-ray scattering and, circular dichroism techniques. The low resolution results showed that the enzyme in the presence of phosphate clearly presented a more compact structure. Thermal-induced unfolding experiments followed by circular dichroism suggested that phosphate rigidified the enzyme. Summarizing, these data suggested that the phosphate itself is able to induce conformational change resulting in the closure movement in the M. tuberculosis 5-enolpyruvylshikimate-3-phosphate synthase.

• Authors: Júlio C Borges, José H Pereira, Igor B Vasconcelos, Giovanni C dos Santos, Johnny R Olivieri, Carlos H I Ramos, Mário S Palma, Luiz A Basso, Diógenes S Santos, Walter F de Azevedo Jr
• Journal: Archives of biochemistry and biophysics (Arch Biochem Biophys) Vol. 452 Issue 2 Pg. 156-64 (Aug 15 2006) ISSN: 0003-9861 [Print] United States
• PMID: 16876105 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Phosphates
• Solutions
• 3-Phosphoshikimate 1-Carboxyvinyltransferase

Topics

• 3-Phosphoshikimate 1-Carboxyvinyltransferase (chemistry, ultrastructure)
• Binding Sites
• Computer Simulation
• Enzyme Activation
• Enzyme Stability
• Hot Temperature
• Models, Chemical
• Models, Molecular
• Mycobacterium tuberculosis (enzymology)
• Phosphates (chemistry)
• Protein Binding
• Protein Conformation
• Protein Folding
• Solutions