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

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.

Quantitative Proteomics of Strong and Weak Biofilm Formers of Enterococcus faecalis Reveals Novel Regulators of Biofilm Formation

“…For instance, the up-regulation of shikimate pathway proteins encoded by aroA and aroK in the strong biofilm former indicates an increased synthesis of aromatic amino acids in the strong biofilm former Ef 63. Certain studies have shown that the production of 5-enolpyruvylshikimate-3-phosphate synthase by aroA can lead to glyphosphate resistance in pathogenic bacteria such as S. aureus and the virulence, growth, and UV tolerance of the plant pathogen Burkholderia glumae (38,49). This suggests that the strong biofilm former Ef 63 can display increased levels of glyphosphate resistance and pathogenesis mechanisms, possibly resulting in higher biofilm formation.…”

Characterization and in Plant Detection of Bacteria That Cause Bacterial Panicle Blight of Rice

“…Previous studies have identified abundance of strains of B. glumae including some highly virulent strains that caused 50% to 75% yield reduction [8] [9]. Additionally, it was predicted that the B. glumae strains in different rice-production regions have some undefined differences in their genome and virulence [3].…”

Characterization of Schu S4 aro mutants as live attenuated tularemia vaccine candidates

“…The production of auxotrophic strains as live attenuated bacterial vaccines is a classic strategy that has proven successful for multiple pathogens including Salmonella Typhi and Shigella [10][11][12][13][14]33]. In this report, we developed rationally defined mutations in the shikimate pathway of F. tularensis, leading to the creation of the Schu S4 mutants ΔaroC, ΔaroD, and ΔaroCΔaroD.…”

“…These metabolic mutants of the human virulent subspecies tularensis strain Schu S4 lack the functional proteins encoded by FTT0876 c (aroC), FTT0471 (aroD), or both genes. The aro genes encode enzymes of the shikimate pathway and have been mutated to attenuate other Gram-negative bacteria [10,11], including Salmonella [12][13][14][15]. This pathway is responsible for synthesis of aromatic amino acids in plants and microbes; deletion of aro genes has been empirically determined to decrease virulence in other organisms [10,13].…”

“…The aro genes encode enzymes of the shikimate pathway and have been mutated to attenuate other Gram-negative bacteria [10,11], including Salmonella [12][13][14][15]. This pathway is responsible for synthesis of aromatic amino acids in plants and microbes; deletion of aro genes has been empirically determined to decrease virulence in other organisms [10,13]. F. tularensis has been documented to produce all of the enzymes involved in the shikimate pathway [16], suggesting that this pathway would be an appropriate target with which to attenuate this pathogen.…”