TY - JOUR
T1 - In vivo influence of in vitro up-regulated genes in the virulence of an APEC strain associated with swollen head syndrome
AU - de Paiva, Jacqueline Boldrin
AU - da Silva, Livia Pilatti Mendes
AU - Casas, Monique Ribeiro Tiba
AU - Conceição, Rogério Arcuri
AU - Nakazato, Gerson
AU - de Pace, Fernanda
AU - Sperandio, Vanessa
AU - da Silveira, Wanderley Dias
N1 - Publisher Copyright:
© 2016 Houghton Trust Ltd.
PY - 2016/1/2
Y1 - 2016/1/2
N2 - Avian Pathogenic Escherichia coli is responsible for significant economic losses in the poultry industry by causing a range of systemic or localized diseases collectively termed colibacillosis. The virulence mechanisms of these strains that are pathogenic in poultry and possibly pathogenic in humans have not yet been fully elucidated. This work was developed to study if over-expressed genes in a microarray assay could be potentially involved in the pathogenicity of an Avian Pathogenic Escherichia coli strain isolated from a swollen head syndrome case. For this study, five over-expressed genes were selected for the construction of null mutants [flgE (flagellar hook), tyrR (transcriptional regulator), potF (putrescine transporter), yehD (putative adhesin) and bfr (bacterioferritin)]. The constructed mutants were evaluated for their capacity for the adhesion and invasion of in vitro cultured cells, their motility capacity, and their pathogenic potential in one-day-old chickens compared with the wild-type strain (WT). The Δbfr strain showed a decreased adhesion capacity on avian fibroblasts compared with WT, in the presence and absence of alpha-D-mannopyranoside, and the ΔpotF strain showed decreased adhesion only in the absence of alpha-D-mannopyranoside. The ΔtyrR mutant had a reduced ability to invade Hep-2 cells. No mutant showed changes in invading CEC-32 cells. The mutants ΔflgE and ΔtyrR showed a decreased ability to survive in HD-11 cells. The motility of the mutant strains Δbfr, ΔyehD and ΔpotF was increased, while the ΔtyrR mutant showed reduction, and the ΔflgE became non-motile. No mutant strain caused the same mortality of the WT in one-day-old chickens, showing attenuation to different degrees.
AB - Avian Pathogenic Escherichia coli is responsible for significant economic losses in the poultry industry by causing a range of systemic or localized diseases collectively termed colibacillosis. The virulence mechanisms of these strains that are pathogenic in poultry and possibly pathogenic in humans have not yet been fully elucidated. This work was developed to study if over-expressed genes in a microarray assay could be potentially involved in the pathogenicity of an Avian Pathogenic Escherichia coli strain isolated from a swollen head syndrome case. For this study, five over-expressed genes were selected for the construction of null mutants [flgE (flagellar hook), tyrR (transcriptional regulator), potF (putrescine transporter), yehD (putative adhesin) and bfr (bacterioferritin)]. The constructed mutants were evaluated for their capacity for the adhesion and invasion of in vitro cultured cells, their motility capacity, and their pathogenic potential in one-day-old chickens compared with the wild-type strain (WT). The Δbfr strain showed a decreased adhesion capacity on avian fibroblasts compared with WT, in the presence and absence of alpha-D-mannopyranoside, and the ΔpotF strain showed decreased adhesion only in the absence of alpha-D-mannopyranoside. The ΔtyrR mutant had a reduced ability to invade Hep-2 cells. No mutant showed changes in invading CEC-32 cells. The mutants ΔflgE and ΔtyrR showed a decreased ability to survive in HD-11 cells. The motility of the mutant strains Δbfr, ΔyehD and ΔpotF was increased, while the ΔtyrR mutant showed reduction, and the ΔflgE became non-motile. No mutant strain caused the same mortality of the WT in one-day-old chickens, showing attenuation to different degrees.
KW - APEC
KW - bfr
KW - flgE
KW - potF
KW - swollen head syndrome
KW - tyrR
KW - virulence
KW - yehD
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UR - http://www.scopus.com/inward/citedby.url?scp=84961285044&partnerID=8YFLogxK
U2 - 10.1080/03079457.2015.1125995
DO - 10.1080/03079457.2015.1125995
M3 - Article
C2 - 26926136
AN - SCOPUS:84961285044
SN - 0307-9457
VL - 45
SP - 94
EP - 105
JO - Avian Pathology
JF - Avian Pathology
IS - 1
ER -