Leveraging structure determination with fragment screening for infectious disease drug targets: MECP synthase from Burkholderia pseudomallei

J Struct Funct Genomics. 2011 Jul;12(2):63-76. doi: 10.1007/s10969-011-9102-6. Epub 2011 Feb 26.

Abstract

As part of the Seattle Structural Genomics Center for Infectious Disease, we seek to enhance structural genomics with ligand-bound structure data which can serve as a blueprint for structure-based drug design. We have adapted fragment-based screening methods to our structural genomics pipeline to generate multiple ligand-bound structures of high priority drug targets from pathogenic organisms. In this study, we report fragment screening methods and structure determination results for 2C-methyl-D-erythritol-2,4-cyclo-diphosphate (MECP) synthase from Burkholderia pseudomallei, the gram-negative bacterium which causes melioidosis. Screening by nuclear magnetic resonance spectroscopy as well as crystal soaking followed by X-ray diffraction led to the identification of several small molecules which bind this enzyme in a critical metabolic pathway. A series of complex structures obtained with screening hits reveal distinct binding pockets and a range of small molecules which form complexes with the target. Additional soaks with these compounds further demonstrate a subset of fragments to only bind the protein when present in specific combinations. This ensemble of fragment-bound complexes illuminates several characteristics of MECP synthase, including a previously unknown binding surface external to the catalytic active site. These ligand-bound structures now serve to guide medicinal chemists and structural biologists in rational design of novel inhibitors for this enzyme.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Bacterial Proteins / chemistry*
  • Binding Sites
  • Burkholderia pseudomallei / enzymology*
  • Catalytic Domain
  • Crystallography, X-Ray
  • Drug Design
  • Ligands
  • Magnetic Resonance Spectroscopy
  • Phosphorus-Oxygen Lyases / chemistry*

Substances

  • Bacterial Proteins
  • Ligands
  • Phosphorus-Oxygen Lyases