Genetic studies of adhesion of atypical enteroaggregative Escherichia coli (EAEC) to biotic and abiotic surfaces

• Grant number: 14/18729-0
• Support Opportunities: Regular Research Grants
• Start date: March 01, 2015
• End date: June 30, 2017
• Field of knowledge: Biological Sciences - Microbiology - Biology and Physiology of Microorganisms
• Principal Investigator: Isabel Cristina Affonso Scaletsky
• Grantee: Isabel Cristina Affonso Scaletsky
• Host Institution: Escola Paulista de Medicina (EPM). Universidade Federal de São Paulo (UNIFESP). Campus São Paulo. São Paulo , SP, Brazil

Abstract

Escherichia coli coli (EAEC) are identified by their ability to produce the aggregative adherence (AA) pattern to cultured epithelial cells. EAEC prototype strains adhere to HEp-2 cells and to intestinal mucosa by virtue of AAF (aggregative adherence fimbriae), which are encoded on pAA plasmids; all AAF biogenesis genes are controlled by the regulator called AggR. However, atypical EAEC strains (aggR-negative) do not express any of the four known AAF variants. This suggests that additional undiscovered AAF variants may exist. In a preliminary characterization of genes involved in the AA phenotype of RN153-1 strain, we identified one mutant markedly deficient in HEp-2 cell adherence. Sequence analysis of the gene disrupted in this mutant revealed a region exhibit up to 97% amino acid similarity to a permease (ygjV). In a recent epidemiological study, atypical EAEC strains were found to be the prevalent pathogens among quilombola children. Further investigation revealed the absence of all variants of AAF in these strains. (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)

MONFARDINI, MARIANE V.; SOUZA, RENATA T.; ROJAS, THAIS C. G.; GUERRIERI, CAROLINE G.; ORIKAZA, CRISTINA; SCALETSKY, ISABEL C. A.. Transposon mutagenesis of atypical enteroaggregative Escherichia coli reveals a hemagglutinin-associated protein that mediates cell adhesion and contributes to the Galleria mellonella virulence. FRONTIERS IN CELLULAR AND INFECTION MICROBIOLOGY, v. 13, p. 8-pg., 2023-06-23. (14/18729-0)