2026-04-17T17:05:12Zhttps://recercat.cat/oai/request

oai:recercat.cat:2445/1815092025-11-19T21:48:06Zcom_2072_1057col_2072_478782col_2072_478902col_2072_478917

00925njm 22002777a 4500 dc Prieto Durán, Alejandro author Bernabeu Lorenzo, Manuel author Sánchez Herrero, José Francisco author Pérez Bosque, Anna author Miró Martí, Ma. Lluïsa author Bäuerl, Christine author Collado, Maria Carmen author Hüttener Queiroz, Mário author Juárez Giménez, Antonio author 2021-11-29T14:50:20Z 2021-11-29T14:50:20Z 2021-11-16 2021-11-29T14:50:20Z Enteroaggregative Escherichia coli (EAEC) strains are one of the diarrheagenic pathotypes. EAEC strains harbor a virulence plasmid (pAA2) that encodes, among other virulence determinants, the aggR gene. The expression of the AggR protein leads to the expression of several virulence determinants in both plasmids and chromosomes. In this work, we describe a novel mechanism that influences AggR expression. Because of the absence of a Rho-independent terminator in the 3′UTR, aggR transcripts extend far beyond the aggR ORF. These transcripts are prone to PNPase-mediated degradation. Structural alterations in the 3′UTR result in increased aggR transcript stability, leading to increased AggR levels. We therefore investigated the effect of increased AggR levels on EAEC virulence. Upon finding the previously described AggR-dependent virulence factors, we detected novel AggR-regulated genes that may play relevant roles in EAEC virulence. Mutants exhibiting high AggR levels because of structural alterations in the aggR 3′UTR show increased mobility and increased pAA2 conjugation frequency. Furthermore, among the genes exhibiting increased fold change values, we could identify those of metabolic pathways that promote increased degradation of arginine, fatty acids and gamma-aminobutyric acid (GABA), respectively. In this paper, we discuss how the AggR-dependent increase in specific metabolic pathways activity may contribute to EAEC virulence. Escheríchia coli Gens Metabolisme Escherichia coli Genes Metabolism Modulation of AggR levels reveals features of virulence regulation in enteroaggregative E. coli