biostudies-literatureUnknown11Flores-Sanchez FConsejo Nacional de Ciencia y TecnologíaA hallmark of enteroaggregative <i>Escherichia coli</i> (EAEC) infection is the formation of an intestinal biofilm, which comprises a mucus layer with immersed bacteria. Pic is an autotransporter secreted by EAEC, and other <i>E. coli</i> pathotypes, and has been involved in two apparently contradictory phenotypes, as a mucus secretagogue and as a mucinase. Here, we investigated this Pic dual activity, mucus secretagogue capability and mucinolytic activity, in human goblet cells that secrete MUC2 and MUC5AC. Pic induced mucus hypersecretion directly in the goblet cells, without other intestinal cell types involved. At the same time, Pic exhibited strong proteolytic activity on the secreted mucins. These activities were independent since a mutation in the serine protease motif (PicS258I) abFrontiers in immunology564953https://www.ebi.ac.uk/biostudies/studies/S-EPMC7705071biostudies-literaturePic Protein From Enteroaggregative <i>E. coli</i> Induces Different Mechanisms for Its Dual Activity as a Mucus Secretagogue and a Mucinase.PMC7705071Flores-Sanchez FNavarro-Garcia FSanchez-Villamil JChavez-Duenas LfalsePic Protein From Enteroaggregative <i>E. coli</i> Induces Different Mechanisms for Its Dual Activity as a Mucus Secretagogue and a Mucinase.A hallmark of enteroaggregative <i>Escherichia coli</i> (EAEC) infection is the formation of an intestinal biofilm, which comprises a mucus layer with immersed bacteria. Pic is an autotransporter secreted by EAEC, and other <i>E. coli</i> pathotypes, and has been involved in two apparently contradictory phenotypes, as a mucus secretagogue and as a mucinase. Here, we investigated this Pic dual activity, mucus secretagogue capability and mucinolytic activity, in human goblet cells that secrete MUC2 and MUC5AC. Pic induced mucus hypersecretion directly in the goblet cells, without other intestinal cell types involved. At the same time, Pic exhibited strong proteolytic activity on the secreted mucins. These activities were independent since a mutation in the serine protease motif (PicS258I) ab2020-01-01T00:00:00Z20202025-04-19T05:46:45.423Z2021-02-20T10:06:54ZS-EPMC77050713328181210.3389/fimmu.2020.564953