Contribution of HCPs to the SPI-6 T6SS-dependent pathogenesis of Salmonella Typhimurium

• Grant number: 19/27644-1
• Support Opportunities: Scholarships in Brazil - Master
• Start date: March 01, 2020
• End date: January 31, 2022
• Field of knowledge: Biological Sciences - Microbiology - Biology and Physiology of Microorganisms
• Principal Investigator: Ethel Bayer Santos
• Grantee: Stephanie Sibinelli de Sousa
• Host Institution: Instituto de Ciências Biomédicas (ICB). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 17/02178-2 - Function of type VI secretion systems of pathogenic bacteria in the interaction with eukaryotic cells, AP.JP

Abstract

Salmonella Typhimurium genome encodes a type VI secretion system (T6SS) within the SPI-6 pathogenicity island important for the establishment of mouse infections. S. Typhimurium SPI-6 T6SS was shown to be important during competitions with bacteria from the intestinal microbiota, and is also activated during infections of macrophages in vitro. Hcp proteins (hemolysin coregulated protein) are structural components of T6SS that help translocate effector proteins into target cells. The SPI-6 T6SS locus has two Hcp proteins: Hcp1 (STM14_0324) and Hcp2 (STM14_0327). S. Typhimurium Hcp1 is essential for promoting T6SS-mediated antibacterial activity by binding to Tae4 toxin. In addition, there are two other Hcps encoded outside this pathogenicity island, called orphans (Hcp3/STM14_3785 and Hcp4/STM14_5414). Although not located at the T6SS locus, orphan Hcps are located near proteins of unknown function that have putative toxic domains. In this context, this project aims to characterize the function of S. Typhimurium proteins Hcp1, Hcp2, Hcp3 and Hcp4 during the infection of macrophages and mammalian hosts, and during bacterial competitions. In addition, we plan to identify new proteins secreted by SPI-6 T6SS associated with Hcps. (AU)

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

SIBINELLI-SOUSA, STEPHANIE; DE ARAUJO-SILVA, ANDRE LUIZ; HESPANHOL, JULIA TAKUNO; ETHEL, BAYER-SANTOS. Revisiting the steps of Salmonella gut infection with a focus on antagonistic interbacterial interactions. FEBS Journal, OCT 2021. (18/04553-8, 19/27644-1, 18/25316-4, 17/02178-2, 21/02536-1)

SIBINELLI-SOUSA, STEPHANIE; HESPANHOL, JULIA TAKUNO; BAYER-SANTOS, ETHEL. Targeting the Achilles' Heel of Bacteria: Different Mechanisms To Break Down the Peptidoglycan Cell Wall during Bacterial Warfare. Journal of Bacteriology, v. 203, n. 7, APR 2021. (18/25316-4, 18/04553-8, 17/02178-2, 19/27644-1)