Virulence traits and expression of bstA, fliC and sopE2 in Salmonella Dublin strains isolated from humans and animals in Brazil

Autor(es)

Vilela, Felipe Pinheiro ^[1] ; Gomes, Carolina Nogueira ^[1] ; Paziani, Mario Henrique ^[1] ; Braz, Vania Santos ^[2] ; Rodrigues, Dalia dos Prazeres ^[3] ; Costa, Renata Garcia ^[3] ; Tiba-Casas, Monique Ribeiro ^[4] ; von Zeska Kress, Marcia Regina ^[1] ; Falcao, Juliana Pfrimer ^[1] ; Campioni, Fabio ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo, Dept Anal Clin Toxicol & Bromatol, Fac Ciencias Farmaceut Ribeirao Preto, Av Cafe S-N, BR-14040903 Ribeirao Preto, SP - Brazil

^[2] UNESP, Dept Ciencias Biol, Fac Ciencias Farmaceut, Campus Araraquara, Rodovia Araraquara Jau, BR-14800903 Araraquara, SP - Brazil

^[3] Fiocruz MS, Fundacao Oswaldo Cruz, Av Brasil 4365, Pavilhao Rocha Lima, BR-21040900 Rio De Janeiro, RJ - Brazil

^[4] Adolfo Lutz Inst, Ctr Bacteriol, Av Dr Arnaldo 351, BR-01255000 Sao Paulo, SP - Brazil

• Tipo de documento: Artigo Científico
• Fonte: INFECTION GENETICS AND EVOLUTION; v. 80, JUN 2020.
• Citações Web of Science: 0

Resumo

Salmonella Dublin is a strongly cattle-adapted serovar that has also been responsible for severe invasive infections in humans. Although invasive infections by non-typhoid Salmonella have increased in developed and in developing countries, in sub-Saharan Africa these infections have been frequently related to Salmonella Typhimurium strains from Sequence Type (ST) 313 that harbor a possible virulence marker, the bstA gene, broadly detected in S. Dublin strains. The aims of this study were to verify the frequency of bstA by PCR in 113 Salmonella Dublin strains isolated from humans (83) and animals (30) in Brazil and the expression by RT-PCR of bstA, sopE2 and fliC in six strains isolated from humans (4) and animals (2). Moreover, the invasion capacity in Caco-2 human epithelial cells and U937 human macrophages, plus in vivo virulence analysis in Galleria mellonella and the motility were verified for 20 S. Dublin strains isolated from humans (15) and animals (5). All studied strains presented the bstA gene. The relative expression rates ranged from 0.1 to 2.3 fold change for bstA and from no expression to 16.6 fold change for sopE2, while no expression was detected for fliC. The invasion in Caco-2 cells ranged from 54.0 to 88.9% and in U937 cells from 72.9 to 98.1% in the 20 strains studied. In addition, 17 strains presented a highly virulent profile in the G. mellonella model and 15 strains presented a nonmotile profile. In conclusion, the presence and expression of bstA in the S. Dublin strains studied suggested that this gene may influence in the invasive characteristic of this serovar. The low expression of sopE2 in strains from human invasive cases suggested that its expression may not be a limiting factor to the invasion of S. Dublin strains. The absence of fliC expression and the low motility rates observed suggest that the flagella absence may favor the host immune system evasion by S. Dublin and the establishment of infection. Moreover, the high mortality rates observed in vivo in Galleria mellonella reinforce the pathogenic potential of S. Dublin strains. (AU)

• Processo FAPESP: 13/25191-3 - Análise fenotípica e sequenciamento do transcriptoma e genoma em linhagens de Salmonella Enteritidis isoladas no período pré e pós-pandemia no Brasil
• Beneficiário: Fábio Campioni
• Modalidade de apoio: Bolsas no Brasil - Pós-Doutorado
• Processo FAPESP: 17/05756-7 - Análise da invasão celular, sobrevivência em macrófagos e expressão dos genes st313-td, sopE2 e fliC em linhagens de Salmonella Dublin isoladas no Brasil
• Beneficiário: Felipe Pinheiro Vilela
• Modalidade de apoio: Bolsas no Brasil - Iniciação Científica
• Processo FAPESP: 19/06947-6 - Caracterização molecular da diversidade genotípica, perfil de resistência e potencial patogênico de linhagens de Salmonella infantis isoladas de fontes diversas no Brasil
• Beneficiário: Felipe Pinheiro Vilela
• Modalidade de apoio: Bolsas no Brasil - Mestrado
• Processo FAPESP: 16/24716-3 - Sequenciamento do genoma, transcriptoma e análise fenotípica de linhagens de Campylobacter coli isoladas de diversas fontes no Brasil
• Beneficiário: Juliana Pfrimer Falcão
• Modalidade de apoio: Auxílio à Pesquisa - Regular