Functional characterisation of Burkholderia pseudomallei biotin protein ligase: A toolkit for anti-melioidosis drug development

Microbiol Res. 2017 Jun:199:40-48. doi: 10.1016/j.micres.2017.03.007. Epub 2017 Mar 19.

Abstract

Burkholderia pseudomallei (Bp) is the causative agent of melioidosis. The bacterium is responsible for 20% of community-acquired sepsis cases and 40% of sepsis-related mortalities in northeast Thailand, and is intrinsically resistant to aminoglycosides, macrolides, rifamycins, cephalosporins, and nonureidopenicillins. There is no vaccine and its diagnosis is problematic. Biotin protein ligase (BirA) which is essential for fatty acid synthesis has been proposed as a drug target in bacteria. Very few bacterial BirA have been characterized, and a better understanding of these enzymes is necessary to further assess their value as drug targets. BirA within the Burkholderia genus have not yet been investigated. We present for the first time the cloning, expression, purification and functional characterisation of the putative Bp BirA and orthologous B. thailandensis (Bt) biotin carboxyl carrier protein (BCCP) substrate. A GFP-tagged Bp BirA was produced and applied for the development of a high-throughput (HT) assay based on our differential scanning fluorimetry of GFP-tagged proteins (DSF-GTP) principle as well as an electrophoretic mobility shift assay. Our biochemical data in combination with the new HT DSF-GTP and biotinylation activity assay could facilitate future drug screening efforts against this drug-resistant organism.

Keywords: Biotin carboxyl carrier protein (BCCP); Biotin protein ligase (BirA); Differential scanning fluorometry (DSF); Electrophoretic mobility shift assay (EMSA); Green fluorescent protein (GFP); Melioidosis.

MeSH terms

  • Acetyl-CoA Carboxylase / metabolism
  • Adenosine Triphosphate / metabolism
  • Amino Acid Sequence
  • Biotin / metabolism
  • Biotinylation
  • Burkholderia pseudomallei / enzymology*
  • Burkholderia pseudomallei / genetics
  • Burkholderia pseudomallei / metabolism*
  • Burkholderia pseudomallei / pathogenicity
  • Drug Delivery Systems
  • Drug Resistance, Multiple, Bacterial
  • Electrophoretic Mobility Shift Assay / methods
  • Escherichia coli / genetics
  • Fatty Acid Synthase, Type II / metabolism
  • Fatty Acids / metabolism
  • Fluorometry / methods
  • Green Fluorescent Proteins
  • High-Throughput Screening Assays
  • Melioidosis / drug therapy
  • Melioidosis / microbiology*
  • Nucleotides
  • Protein Domains
  • Protein Refolding
  • Repressor Proteins / genetics
  • Repressor Proteins / metabolism
  • Sequence Alignment
  • Sulfurtransferases / genetics*
  • Sulfurtransferases / metabolism*

Substances

  • Fatty Acids
  • Nucleotides
  • Repressor Proteins
  • Green Fluorescent Proteins
  • Biotin
  • Adenosine Triphosphate
  • Sulfurtransferases
  • biotin synthetase
  • Fatty Acid Synthase, Type II
  • Acetyl-CoA Carboxylase
  • biotin carboxyl carrier protein