Perez-Reytor, D.Pavon, A.Lopez-Joven, C.Ramirez-Araya, S.Pena-Varas, C.Plaza, N.Alegria-Arcos, M.Corsini, G.Jana, V.Pavez, L.del Pozo, T.Bastias, R.Blondel, C.J.Ramirez, D.Garcia, K.2021-07-282021-07-282020-09Frontiers in Cellular and Infection MicrobiologyOpen AccessVolume 1024 September 2020 Article number 4822235-2988http://repositorio.unab.cl/xmlui/handle/ria/19533Indexación: Scopus.Vibrio parahaemolyticus non-toxigenic strains are responsible for about 10% of acute gastroenteritis associated with this species, suggesting they harbor unique virulence factors. Zonula occludens toxin (Zot), firstly described in Vibrio cholerae, is a secreted toxin that increases intestinal permeability. Recently, we identified Zot-encoding genes in the genomes of highly cytotoxic Chilean V. parahaemolyticus strains, including the non-toxigenic clinical strain PMC53.7. To gain insights into a possible role of Zot in V. parahaemolyticus, we analyzed whether it could be responsible for cytotoxicity. However, we observed a barely positive correlation between Caco-2 cell membrane damage and Zot mRNA expression during PMC53.7 infection and non-cytotoxicity induction in response to purified PMC53.7-Zot. Unusually, we observed a particular actin disturbance on cells infected with PMC53.7. Based on this observation, we decided to compare the sequence of PMC53.7-Zot with Zot of human pathogenic species such as V. cholerae, Campylobacter concisus, Neisseria meningitidis, and other V. parahaemolyticus strains, using computational tools. The PMC53.7-Zot was compared with other toxins and identified as an endotoxin with conserved motifs in the N-terminus and a variable C-terminal region and without FCIGRL peptide. Notably, the C-terminal diversity among Zots meant that not all of them could be identified as toxins. Structurally, PMC53.7-Zot was modeled as a transmembrane protein. Our results suggested that it has partial 3D structure similarity with V. cholerae-Zot. Probably, the PMC53.7-Zot would affect the actin cytoskeletal, but, in the absence of FCIGRL, the mechanisms of actions must be elucidated. © Copyright © 2020 Pérez-Reytor, Pavón, Lopez-Joven, Ramírez-Araya, Peña-Varas, Plaza, Alegría-Arcos, Corsini, Jaña, Pavez, del Pozo, Bastías, Blondel, Ramírez and García.enCampylobacter concisusintestinal permeabilitynon-toxigenic strainsProtein structure predictionVibrio choleraeVibrio parahaemolyticusZonula occludens toxinZotArtículoAttribution 4.0 International (CC BY 4.0)10.3389/fcimb.2020.00482