Site-directed mutagenesis of a new autotransporter in an avian pathogenic Escherichia coli strain (APEC) and evaluation of the contribution of this gene to pathogenesis

• Grant number: 13/09167-5
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: September 01, 2013
• End date: December 31, 2016
• Field of knowledge: Biological Sciences - Genetics - Molecular Genetics and Genetics of Microorganisms
• Principal Investigator: Wanderley Dias da Silveira
• Grantee: Thaís Cabrera Galvão Rojas
• Host Institution: Instituto de Biologia (IB). Universidade Estadual de Campinas (UNICAMP). Campinas , SP, Brazil

Abstract

Currently, Brazil is the largest exporter of chicken meat and the third largest producer in the world, therefore the poultry industry is important to domestic and export economies. Despite being an important economic sector, the poultry industry is subject to factors that could significantly affect its revenues and costs. Among them, the infections caused by avian pathogenic Escherichia coli (APEC) are responsible for high morbidity and mortality. Avian pathogenic strains are associated with extraintestinal infections and diseases are known as colibacillosis, which encompass the large number of different infections. Furthermore, studies have shown that APEC strains and Extra-intestinal pathogenic E. coli of human origin (ExPEC) share pathogenicity characteristics such as serogroups, phylogenetic groups, virulence related plasmids sequences, bacterial adhesion, iron uptake systems and toxins. Numerous studies have been conducted seeking to establish the mechanisms of pathogenicity, the identification of new markers and description of virulence proteins in APEC. However, more studies are needed to understand and identify the pathogenicity mechanisms and virulence factors related to this pathotype. The availability of genome sequences allows comparative analyses between different strains, enabling the access to gene content variability, genomic organization and comparative genomes studies. The comparison of Brazilian sequenced strains (SEPT362, SCI-07, O08 and S17) has allowed us to observe the great variability related to the presence/absence of virulence factors. Another important issue related to the study of the genomes was that approximately 20% of the annotated genes have unknown function and the gene product described as hypothetical protein. These results show the necessity to find new genes associated with virulence. Motivated by the need, our research group has already identified and characterized in silico, a gene encoding autotransporter protein, with adhesin domains, not described in APEC. The objective of this project is to build a mutated APEC strain, through the deletion of this autotransporter protein and verify its contribution to pathogenicity, their biological effects (adhesion and invasion abilities in cell lines grown in vitro, biofilm production, motility, etc.) and its influence on global gene transcription.

Scientific publications

(5)

(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)

VERMA, RENU; GALVAO ROJAS, THAS CABRERA; MALUTA, RENATO PARIZ; LEITE, JANANA LUISA; MENDES DA SILVA, LIVIA PILATTI; NAKAZATO, GERSON; DA SILVEIRA, WANDERLEY DIAS. Fimbria-Encoding Gene yadC Has a Pleiotropic Effect on Several Biological Characteristics and Plays a Role in Avian Pathogenic Escherichia coli Pathogenicity. Infection and Immunity, v. 84, n. 1, p. 187-193, JAN 2016. (12/23289-3, 12/04391-1, 12/05073-3, 13/09167-5, 14/04860-7)

MALUTA, RENATO P.; NICHOLSON, BRYON; LOGUE, CATHERINE M.; NOLAN, LISA K.; ROJAS, THAIS C. G.; DA SILVEIRA, WANDERLEY DIAS. Complete Genomic Sequence of an Avian Pathogenic Escherichia coli Strain of Serotype O7:HNT. MICROBIOLOGY RESOURCE ANNOUNCEMENTS, v. 4, n. 1, JAN-FEB 2016. (13/25615-8, 13/09167-5, 12/05073-3)

VERMA, RENU; GALVAO ROJAS, THAIS CABRERA; MALUTA, RENATO PARIZ; LEITE, JANAINA LUISA; NAKAZATO, GERSON; DE SILVEIRA, WANDERLEY DIAS. Role of hypothetical protein YicS in the pathogenicity of Avian Pathogenic Escherichia coli in vivo and in vitro. MICROBIOLOGICAL RESEARCH, v. 214, p. 28-36, 2018. (12/23289-3, 12/09655-7, 12/05073-3, 15/03860-6, 13/09167-5, 14/04860-7)

MALUTA, RENATO PARIZ; LOGUE, CATHERINE MARY; TIBA CASAS, MONIQUE RIBEIRO; MENG, TING; LOPES GUASTALLI, ELISABETE APARECIDA; GALVAO ROJAS, THAIS CABRERA; MONTELLI, AUGUSTO CEZAR; SADATSUNE, TERUE; RAMOS, MARCELO DE CARVALHO; NOLAN, LISA KAY; et al. Overlapped Sequence Types (STs) and Serogroups of Avian Pathogenic (APEC) and Human Extra-Intestinal Pathogenic (ExPEC) Escherichia coli Isolated in Brazil. PLoS One, v. 9, n. 8, AUG 12 2014. (12/04931-6, 13/09167-5, 12/05073-3)

MALUTA, RENATO P.; NICHOLSON, BRYON; LOGUE, CATHERINE M.; NOLAN, LISA K.; ROJAS, THAIS C. G.; DA SILVEIRA, WANDERLEY DIAS. Complete Genomic Sequence of an Avian Pathogenic Escherichia coli Strain of Serotype O7:HNT. GENOME ANNOUNCEMENTS, v. 4, n. 1, p. 2-pg., 2016-01-01. (13/09167-5, 13/25615-8, 12/05073-3)