The transcriptional regulator Lrp activates the expression of genes involved in tilivalline enterotoxin biosynthesis in Klebsiella oxytoca.

This article discusses the role of the transcriptional regulator Lrp in activating the expression of genes involved in the biosynthesis of the tilivalline enterotoxin in Klebsiella oxytoca. The tilivalline enterotoxin is a non-ribosomal peptide that causes antibiotic-associated hemorrhagic colitis. The study found that Lrp directly activates the transcription of the genes responsible for tilivalline biosynthesis by binding to the intergenic regulatory region in a leucine-dependent manner. The lack of Lrp resulted in reduced cytotoxicity of K. oxytoca on HeLa cells due to decreased tilivalline production. This research provides new insights into how cytotoxin-producing K. oxytoca strains control the expression of genes involved in their virulence. [Extracted from the article]