RESUMO
Gallibacterium anatis is a member of the Pasteurellaceae family and is an opportunistic pathogen that causes gallibacteriosis in chickens. Stress plays a relevant role in promoting the development of pathogenicity in G. anatis. Epinephrine (E) and norepinephrine (NE) are relevant to stress; however, their effects on G. anatis have not been elucidated. In this work, we evaluated the effects of E and NE on the growth, biofilm formation, expression of adhesins, and proteases of two G. anatis strains, namely, the hemolytic 12656-12 and the nonhemolytic F149T biovars. E (10 µM/mL) and NE (30 and 50 µM/mL) increased the growth of G. anatis 12656-12 by 20 % and 25 %, respectively. E did not affect the growth of F149T, whereas 40 µM/mL NE decreased bacterial growth by 25 %. E and NE at a dose of 30-50 µM/mL upregulated five fibrinogen adhesins in the 12565-12 strain, whereas no effect was observed in the F149T strain. NE increased proteolytic activity in both strains, whereas E diminished proteolytic activity in the 12656-12 strain. E and NE reduced biofilm formation (30 %) and increased Congo red binding (15 %) in both strains. QseBC is the E and NE two-component detection system most common in bacteria. The qseC gene, which is the E and NE receptor in bacteria, was identified in the genomic DNA of the 12565-12 and F149TG. anatis strains via PCR amplification. Our results suggest that QseC can detect host changes in E and NE concentrations and that catecholamines can modulate the expression of several virulence factors in G. anatis.
Assuntos
Biofilmes , Galinhas , Epinefrina , Regulação Bacteriana da Expressão Gênica , Norepinefrina , Pasteurellaceae , Fatores de Virulência , Fatores de Virulência/genética , Fatores de Virulência/metabolismo , Norepinefrina/farmacologia , Norepinefrina/metabolismo , Epinefrina/farmacologia , Biofilmes/crescimento & desenvolvimento , Biofilmes/efeitos dos fármacos , Pasteurellaceae/genética , Pasteurellaceae/patogenicidade , Pasteurellaceae/efeitos dos fármacos , Pasteurellaceae/metabolismo , Animais , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Adesinas Bacterianas/genética , Adesinas Bacterianas/metabolismo , Peptídeo Hidrolases/metabolismo , Peptídeo Hidrolases/genética , Doenças das Aves Domésticas/microbiologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Infecções por Pasteurellaceae/microbiologia , Infecções por Pasteurellaceae/veterináriaRESUMO
Introduction: Gallibacterium anatis causes gallibacteriosis in birds. These bacteria produce biofilms and secrete several fimbrial appendages as tools to cause disease in animals. G. anatis strains contain up to three types of fimbriae. Complete genome sequencing is the strategy currently used to determine variations in the gene content of G. anatis, although today only the completely circularized genome of G. anatis UMN179 is available. Methods: The appearance of growth of various strains of G. anatis in liquid culture medium was studied. Biofilm production and how the amount of biofilm was affected by DNase, Proteinase K, and Pronase E enzymes were analyzed. Fimbrial gene expression was performed by protein analysis and qRT-PCR. In an avian model, the pathogenesis generated by the strains G. anatis ESV200 and 12656-12 was investigated. Using bioinformatic tools, the complete genome of G. anatis ESV200 was comparatively studied to search for virulence factors that would help explain the pathogenic behavior of this strain. Results and Discussion: G. anatis ESV200 strain differs from the 12656-12 strain because it produces a biofilm at 20%. G. anatis ESV200 strain express fimbrial genes and produces biofilm but with a different structure than that observed for strain 12656-12. ESV200 and 12656-12 strains are pathogenic for chickens, although the latter is the most virulent. Here, we show that the complete genome of the ESV200 strain is similar to that of the UNM179 strain. However, these strains have evolved with many structural rearrangements; the most striking chromosomal arrangement is a Maverick-like element present in the ESV200 strain.
RESUMO
Pasteurellaceae family members obtain iron directly from host proteins or through siderophore-dependent mechanisms. Although Gallibacterum anatis expresses different virulence factors, its response to growth under iron restriction is unknown. G. anatis cultured in the presence of 2,2'-dipyridyl, up-expressed an approximately 65 kDa protein and repressed the expression of a 70 kDa protein. MALDI-TOF analysis of those proteins indicated homology with CirA (65 kDa), a protein involved in iron-siderophore acquisition in Mannheimia succinoproducens and a TonB-dependent receptor (70 kDa protein), a protein that binds chicken hemoglobin; however, G. anatis siderophore production was not detected by chromo azurol S (CAS)-BHI agar determination. This putative G. anatis siderophore receptor is under Fur control, but not the hemoglobin binding protein, as observed in G. anatis 12656-12 fur mutant (Ω fur 126.13) grown in the presence or not of 2,2'-dipyridyl. The addition of FeCl3 to the culture medium diminished the growth and biofilm production in approximately 30% and 35%, respectively, in the wild-type strain, but the growth of Ω fur 126.13 strain was not affected and biofilm production increased in 35%. G. anatis Ω fur 126.13 presented lower virulence when it was inoculated to 35-day-old chickens in comparison to the wild-type strain. The induction of more than one iron uptake mechanism could benefit pathogenic microorganisms such as Gallibacterium.
RESUMO
Gallibacterium anatis, a member of the Pasteurellaceae family, leads to decrease in egg-production, animal welfare and increase in mortality. This study aimed to diagnose G. Anatis, which caused economic losses in laying hens by using conventional and molecular techniques. In this study, G. anatis was examined from a total of 200 dead chicken tissues (heart, liver, lung, spleen and trachea) in laying hen farms that observed a decrease in egg production with respiratory system infection. Conventional methods based on colony morphology, sugar fermentation tests and hemolytic properties and molecular conformation using 16S rRNA-23S rRNA specific primers were performed to identify G. anatis. G. anatis was isolated in 20 (10%) of the examined samples and isolates were confirmed by conventional PCR. A total of 11 (2.2%) positivity was obtained as isolates were the result of PCR performed on tissues and organs directly. As a result, the presence of G. anatis was detected for the first time in Turkey by this study. It was thought that G. anatis may have a role in egg production losses due to respiratory tract infection in poultry and this situation may be a guide for poultry clinicians and microbiologists.
Assuntos
Animais , Galinhas/microbiologia , Infecções por Pasteurellaceae/diagnóstico , Infecções por Pasteurellaceae/veterinária , Reação em Cadeia da Polimerase/veterináriaRESUMO
Gallibacterium anatis, a member of the Pasteurellaceae family, leads to decrease in egg-production, animal welfare and increase in mortality. This study aimed to diagnose G. Anatis, which caused economic losses in laying hens by using conventional and molecular techniques. In this study, G. anatis was examined from a total of 200 dead chicken tissues (heart, liver, lung, spleen and trachea) in laying hen farms that observed a decrease in egg production with respiratory system infection. Conventional methods based on colony morphology, sugar fermentation tests and hemolytic properties and molecular conformation using 16S rRNA-23S rRNA specific primers were performed to identify G. anatis. G. anatis was isolated in 20 (10%) of the examined samples and isolates were confirmed by conventional PCR. A total of 11 (2.2%) positivity was obtained as isolates were the result of PCR performed on tissues and organs directly. As a result, the presence of G. anatis was detected for the first time in Turkey by this study. It was thought that G. anatis may have a role in egg production losses due to respiratory tract infection in poultry and this situation may be a guide for poultry clinicians and microbiologists.(AU)
Assuntos
Animais , Galinhas/microbiologia , Infecções por Pasteurellaceae/diagnóstico , Infecções por Pasteurellaceae/veterinária , Reação em Cadeia da Polimerase/veterináriaRESUMO
Gallibacterium, which is a bacterial pathogen in chickens, can form biofilms. Amyloid proteins present in biofilms bind Congo red dye. The aim of this study was to characterize the cell-surface amyloid-like protein expressed in biofilms formed by Gallibacterium strains and determine the relationship between this protein and curli, which is an amyloid protein that is commonly expressed by members of the Enterobacteriaceae family. The presence of amyloid-like proteins in outer membrane protein samples from three strains of G. anatis and one strain of Gallibacterium genomospecies 2 was evaluated. A protein identified as elongation factor-Tu (EF-Tu) by mass spectrometric analysis and in silico analysis was obtained from the G. anatis strain F149T. This protein bound Congo red dye, cross-reacted with anti-curli polyclonal serum, exhibited polymerizing properties and was present in biofilms. This protein also reacted with pooled serum from chickens that were experimentally infected with G. anatis, indicating the in vivo immunogenicity of this protein. The recombinant EF-Tu purified protein, which was prepared from G. anatis 12656-12, polymerizes under in vitro conditions, forms filaments and interacts with fibronectin and fibrinogen, all of which suggest that this protein functions as an adhesin. In summary, EF-Tu from G. anatis presents amyloid characteristics, is present in biofilms and could be relevant for the pathogenesis of G. anatis.