Prevalence and phenotypic analysis of the type II toxin-antitoxin (TA) system in Shiga toxin producing Escherichia coli (STEC) strains

• Grant number: 23/10391-9
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: October 01, 2023
• End date: September 30, 2024
• Field of knowledge: Biological Sciences - Microbiology - Biology and Physiology of Microorganisms
• Principal Investigator: Roxane Maria Fontes Piazza
• Grantee: Rodrigo Mitsui Maluhy
• Host Institution: Instituto Butantan. Secretaria da Saúde (São Paulo - Estado). São Paulo , SP, Brazil
• Associated research grant: 17/14821-7 - Exploring novel virulence strategies in Escherichia coli, AP.TEM

Abstract

Toxin-antitoxin (TA) systems are genetic modules that are widespread in prokaryotes and archaea. On the chromosome, these systems may be involved in several virulence factors of pathogenic bacteria. In E. coli K12, 36 TA systems have been described, of which type II is the most abundant and studied. Within the scope of E. coli that cause diarrhea, the STEC pathotype stands out as one of the main causative agents of diarrhea, causing from mild conditions to progressing to more serious infections, such as hemorrhagic colitis and hemolytic uremic syndrome (HUS). In Argentina, HUS is endemic and the concern with outbreaks in this country is constant, since it has a relevant role in the export of beef and it is known today that cattle are the main reservoir of STEC. For this reason, important research related to treatment, diagnosis and therapy is carried out in Latin America for STEC. In this scenario, investigating TA systems in pathogenic bacteria, such as STEC, can provide important information regarding their role in the virulence and persistence of this pathotype of great importance in public health. Thus, this project proposes to analyze the prevalence of the main genes of the type II TA system in STEC strains and to perform mutation and complementation in one of these genes, in order to evaluate its possible role in the biofilm formation phenotype.