Detection and characterization of the ferric uptake regulator (fur) gene in Plesiomonas shigelloides.

Iron availability plays an important role in the virulence of micro-organisms, which develops different systems for iron acquisition. The expression of genes involved in iron uptake systems is usually regulated by Fur, a transcriptional regulator. Plesiomonas shigelloides is a Gram-negative food- and water-borne enteropathogen. Even though the mechanisms involved in the pathogenicity of P. shigelloides are not properly elucidated, iron seems to be implicated in the development of human infections and in the production of potential virulence factors; however, detection and characterization of fur gene has not been performed in this bacterium. In this work the presence of a conserved fur gene was determined in six strains of P. shigelloides. The expression of fur was studied under different culture conditions and it was demonstrated to be higher when the micro-organism was cultured under iron-restricted than under iron-abundance conditions. SIGNIFICANCE AND IMPACT OF THE STUDY: Significance and Impact of the Study: This study provides evidence of the presence of a conserved fur gene in strains of Plesiomonas shigelloides. Expression of this gene is higher when the micro-organism is cultured under iron-restricted conditions. The study provides clues to understand the role of iron in the regulation of important activities of P. shigelloides.