Dataset Information

Characterization of an OrtT-like toxin of Salmonella enterica serovar Houten.

ABSTRACT: The Escherichia coli GhoT/GhoS system is a type V toxin-antitoxin system in which the antitoxin GhoS cleaves the GhoT mRNA, controlling its translation. GhoT is a small hydrophobic protein that damages bacterial membranes. OrtT is a GhoT-like toxin, but it apparently lacks a corresponding antitoxin and serves a different physiologic role. Using a profile hidden Markov model approach, a Salmonella enterica serovar Houten genome was screened to obtain homologs of GhoT/OrtT. We only found one protein (referred to here as OrtT-Sal) that shared more sequence identity with OrtT than GhoT. The chromosomal region around the coding sequence of OrtT-Sal suggests that it is an orphan toxin and can be under RpoH activation. To study OrtT-Sal, we chemically synthesized and expressed in E. coli the whole toxin and its N- and C-terminal regions (OrtT-Sal1-29 and OrtT-Sal29-57, respectively). Our findings have shown that the overproduction of the polypeptides resulted in severe growth inhibition and cell lysis. Using circular dichroism, we found that OrtT-Sal, OrtT-Sal1-29, and OrtT-Sal29-57 form an alpha-helical structure in the presence of SDS micelles or TFE. Finally, using carboxyfluorescein-loaded lipid vesicles, we determined that the polypeptides damage lipid membrane directly.

SUBMITTER: Barbosa LCB

PROVIDER: S-EPMC6863217 | biostudies-literature | 2019 Jul

REPOSITORIES: biostudies-literature

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Characterization of an OrtT-like toxin of Salmonella enterica serovar Houten.

Barbosa Luiz Carlos Bertucci LCB Dos Santos Carrijo Rodolfo R da Conceição Milena Barbosa MB Campanella Jonatas Erick Maimoni JEM Júnior Edson Crusca EC Secches Thais Oliveira TO Bertolini Maria Celia MC Marchetto Reinaldo R

Brazilian journal of microbiology : [publication of the Brazilian Society for Microbiology] 20190504 3

The Escherichia coli GhoT/GhoS system is a type V toxin-antitoxin system in which the antitoxin GhoS cleaves the GhoT mRNA, controlling its translation. GhoT is a small hydrophobic protein that damages bacterial membranes. OrtT is a GhoT-like toxin, but it apparently lacks a corresponding antitoxin and serves a different physiologic role. Using a profile hidden Markov model approach, a Salmonella enterica serovar Houten genome was screened to obtain homologs of GhoT/OrtT. We only found one prote ...[more]

PMID: 31055774

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Dataset Information

Characterization of an OrtT-like toxin of Salmonella enterica serovar Houten.

Publications

Characterization of an OrtT-like toxin of Salmonella enterica serovar Houten.

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