The roles of the shikimate pathway genes, aroA and aroB, in virulence, growth and UV tolerance of Burkholderia glumae strain 411gr-6

Mol Plant Pathol. 2014 Dec;15(9):940-7. doi: 10.1111/mpp.12147. Epub 2014 May 23.

Abstract

Burkholderia glumae is the major causal agent of bacterial panicle blight of rice, which is a growing disease problem for rice growers worldwide. In our previous study, some B. glumae strains showed pigmentation phenotypes producing at least two (yellow-green and purple) pigment compounds in casein-peptone-glucose agar medium. The B. glumae strains LSUPB114 and LSUPB116 are pigment-deficient mutant derivatives of the virulent and pigment-proficient strain 411gr-6, having mini-Tn5gus insertions in aroA encoding 3-phosphoshikimate 1-carboxyvinyltransferase and aroB encoding 3-dehydroquinate synthase, respectively. Both enzymes are known to be involved in the shikimate pathway, which leads to the synthesis of aromatic amino acids. Here, we demonstrate that aroA and aroB are required for normal virulence in rice and onion, growth in M9 minimal medium and tolerance to UV light, but are dispensable for the production of the phytotoxin toxoflavin. These results suggest that the shikimate pathway is involved in bacterial pathogenesis by B. glumae without a significant role in the production of toxoflavin, a major virulence factor of this pathogen.

Keywords: Bacterial panicle blight of rice; Burkholderia glumae; bacterial pigments.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.

MeSH terms

  • Adaptation, Physiological / genetics*
  • Adaptation, Physiological / radiation effects
  • Burkholderia / genetics*
  • Burkholderia / growth & development
  • Burkholderia / pathogenicity*
  • Burkholderia / radiation effects
  • Genes, Bacterial*
  • Glycine / analogs & derivatives
  • Glycine / toxicity
  • Metabolic Networks and Pathways / genetics*
  • Metabolic Networks and Pathways / radiation effects
  • Microbial Viability / drug effects
  • Microbial Viability / radiation effects
  • Mutation / genetics
  • Onions / microbiology
  • Oryza / microbiology
  • Pigments, Biological / metabolism
  • Plant Diseases / microbiology
  • Pyrimidinones / metabolism
  • Shikimic Acid / metabolism*
  • Triazines / metabolism
  • Ultraviolet Rays*
  • Virulence / radiation effects

Substances

  • Pigments, Biological
  • Pyrimidinones
  • Triazines
  • Shikimic Acid
  • glyphosate
  • toxoflavin
  • Glycine