Construction of Salmonella enterica subspecies enterica serovar Gallinarum biovar Gallinarum and serovar Enteritidis mutant strains: assessment of pathogeny to commercial birds (Gallus gallus)

• Grant number: 11/18276-7
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: March 01, 2012
• End date: August 31, 2014
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Pathology
• Principal Investigator: Angelo Berchieri Junior
• Grantee: Oliveiro Caetano de Freitas Neto
• Host Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil

Abstract

This study aims at generating Salmonella Gallinarum (SG) and Salmonella Enteritidis (SE) mutant strains for pathological studies in birds. In order to produce these mutants, the Lambda-red methodology will be adopted. This technique allows removing antibiotic resistance markers after inactivation of target genes. The present research project will complement our previous study about genes involving in B12 vitamin biosynthesis (cob operon) (FAPESP: 08/54517-6) which yielded the vaccinal strain SG ”cobS ”cbiA. Now we would like to investigate the role of genes responsible for propanediol-desidratase (pdu operon) which converts 1,2-propanediol to propionaldehyde and requires B12 vitamin as cofactor. Two SE mutant strains will be produced, a mutant with the genes pduC, pduD and pduE defectives (SE ”pduC ”pduD ”pduE) and another one with inactivation of genes of pdu and cob operons simultaneously (SE ”cobS ”cbiA ”pduC ”pduD ”pduE). In another study which aimed at investigating the role of flagellum in pathogeny of avian salmonelosis (FAPESP: 07-59233-3), a SG mutant strain capable of producing flagella, inducing pro-inflammatory responses and colonizing chicken's caeca was generated (SG Fla+). Now, we also intend to reconstruct the vaccinal strain SG ”cobS ”cbiA (by Lambda-red) removing antibiotic resistance genes from its genome and attenuate SG Fla+ by inactivation of cobS and cbiA genes (SG Fla+ ”cobS ”cbiA). This project will further explore and also unite two different subjects that have been investigated by this research group. (AU)