Computational Analysis of the Ligand-Binding Sites of the Molecular Chaperone OppA from Yersinia pseudotuberculosis.

The function of chaperones is to correct or degrade misfolded proteins inside the cell. Classic molecular chaperones such as GroEL and DnaK have not been found in the periplasm of Yersinia pseudotuberculosis. Some periplasmic substrate-binding proteins could be bifunctional, such as OppA. Using bioinformatic tools, we try to elucidate the nature of the interactions between OppA and ligands from four proteins with different oligomeric states. Using the crystal structure of the proteins Mal12 alpha-glucosidase from Saccharomyces cerevisiae S288C, LDH rabbit muscle lactate dehydrogenase, EcoRI endonuclease from Escherichia coli and THG Geotrichum candidum lipase, a hundred models were obtained in total, including five different ligands from each enzyme with five conformations of each ligand. The best values for Mal12 stem from ligands 4 and 5, with conformation 5 for both; for LDH, ligands 1 and 4, with conformations 2 and 4, respectively; for EcoRI, ligands 3 and 5, with conformation 1 for both; and for THG, ligands 2 and 3, with conformation 1 for both. The interactions were analyzed with LigProt, and the length of the hydrogen bridges has an average of 2.8 to 3.0 Å. The interaction within the OppA pocket is energetically favored due to the formation of hydrogen bonds both of OppA and of the selected enzymes. The Asp 419 residue is important in these junctions.

Acute death of kangaroos in a zoo due to highly pathogenic Corynebacterium pseudotuberculosis and Yersinia pseudotuberculosis

Background: “Lumpy jaw” is disease effecting wallabies and kangaroos, particularly in Macropus rufus and Macropusgiganteus. In the most serious situations, additional tooth loss and fistulas follow, accompanied by a stench, weight loss,and eventually death due to sepsis or blood poisoning. “Lumpy jaw” disease has seriously affected the normal display andhealth of kangaroos, and cause a huge economic loss. There was an outbreak of jaw infection in kangaroos at the HongshanForest Zoo. Two Macropus giganteus and two Macropus rufus died of “lumpy jaw”. The main objective of the describingcase was to isolate pathogens, provide a basis for follow-up treatment, and serve to establish a disease prevention protocol.Case: Four grown-up kangaroos (two Macropus giganteus and two Macropus rufus) were raised in Hongshan Forest Zoo,which had obviously clinical symptoms, such as oral lesions of pus, necrotic tissue, rotting teeth, then died of “lumpyjaw”. Oral swab samples were collected from the lesion sites of the dying kangaroos. Mice experiments were conducted toexamine the pathogenicity of the strains. Tests of antimicrobial susceptibity were performed to prescribe with better drugtreatments for kangaroos. Corynebacterium pseudotuberculosis and Yersinia pseudotuberculosis were identified based onmorphology, culture characteristics and biochemical tests. Corynebacterium pseudotuberculosis (G+) in Sucrose, Mannitol,Lactose, Maltose, Glucose tubes were positive, that acids and gases both production, in Gelatin liquefaction, Indol test,MR were positive, that only acids production, others were negative; Yersinia pseudotuberculosis (G-) in Urea, MR werepositive, that only acids production, others were negative.The infected mice presented with gum erosion or ulcers whenthe two pathogens were injected subcutaneous at the oral regional by 2-3 point at 0.2 mL of individual strains 1.0×109CFU/mouse...(AU)

Acute death of kangaroos in a zoo due to highly pathogenic Corynebacterium pseudotuberculosis and Yersinia pseudotuberculosis

Background: “Lumpy jaw” is disease effecting wallabies and kangaroos, particularly in Macropus rufus and Macropusgiganteus. In the most serious situations, additional tooth loss and fistulas follow, accompanied by a stench, weight loss,and eventually death due to sepsis or blood poisoning. “Lumpy jaw” disease has seriously affected the normal display andhealth of kangaroos, and cause a huge economic loss. There was an outbreak of jaw infection in kangaroos at the HongshanForest Zoo. Two Macropus giganteus and two Macropus rufus died of “lumpy jaw”. The main objective of the describingcase was to isolate pathogens, provide a basis for follow-up treatment, and serve to establish a disease prevention protocol.Case: Four grown-up kangaroos (two Macropus giganteus and two Macropus rufus) were raised in Hongshan Forest Zoo,which had obviously clinical symptoms, such as oral lesions of pus, necrotic tissue, rotting teeth, then died of “lumpyjaw”. Oral swab samples were collected from the lesion sites of the dying kangaroos. Mice experiments were conducted toexamine the pathogenicity of the strains. Tests of antimicrobial susceptibity were performed to prescribe with better drugtreatments for kangaroos. Corynebacterium pseudotuberculosis and Yersinia pseudotuberculosis were identified based onmorphology, culture characteristics and biochemical tests. Corynebacterium pseudotuberculosis (G+) in Sucrose, Mannitol,Lactose, Maltose, Glucose tubes were positive, that acids and gases both production, in Gelatin liquefaction, Indol test,MR were positive, that only acids production, others were negative; Yersinia pseudotuberculosis (G-) in Urea, MR werepositive, that only acids production, others were negative.The infected mice presented with gum erosion or ulcers whenthe two pathogens were injected subcutaneous at the oral regional by 2-3 point at 0.2 mL of individual strains 1.0×109CFU/mouse...

Ribotyping and virulence markers of Yersinia pseudotuberculosis strains isolated from animals in Brazil

Ribotyping and virulence markers has been used to investigate 68 Yersinia pseudotuberculosis strains of serogroups O:1a and O:3. The strains were isolated from clinical material obtained from healthy and sick animals in the Southern region of Brazil. Ribotypes were identified by double digestion of extracted DNA with the restriction endonucleases SmaI and PstI, separation by electrophoresis and hybridization with a digoxigenin-labeled cDNA probe. The presence of the chromosomal virulence marker genes inv, irp1, irp2, psn, ybtE, ybtP-ybtQ, and ybtX-ybtS, of the IS100 insertion sequence, and of the plasmid gene lcrF was detected by polymerase chain reaction. The strains were grouped into four distinct ribotypes, all of them comprising several strains. Ribotypes 1 and 4 presented distinct profiles, with 57.3 percent genetic similarity, ribotypes 2 and 3 presented 52.5 percent genetic similarity, and genetic similarity was 45 percent between these two groups (1/4 and 2/3). All strains possessed the inv, irp1, and irp2 genes. Additionally, strains of serogroup O:1a carried psn, ybtE, ybtP-ybtQ, ybtX-ybtS, and IS100. As expected lcrF was only detected in strains harboring the virulence plasmid. These data demonstrate the presence of Y. pseudotuberculosis strains harboring genotypic virulence markers in the livestock from Southern Brazil and that the dissemination of these bacteria may occur between herds.

Isolation of Yersinia pseudotuberculosis from buffalo (Bubalus bubalis) feces / Isolamento de Yersinia pseudotuberculosis de fezes de búfalo (Bubalus bubalis)

Fecal samples from 119 healthy buffaloes, from 5 farms, diluted in 10% brain heart infusion, were maintained for 3 weeks at 4C and subcultured weekly onto Mac Conckey agar and Yersinia selective agar with antimicrobial supplement. Yersinia pseudotuberculosis serotype Olll was isolated from only one farm, where an outbreak of yersiniosis was occurring. The bacteria was isolated in 21 of the 25 samples from adult, healthy females and in all the 9 samples from healthy calves. It was not isolated in the samples from other farms, 2 especially, where yersiniosis had been diagnosed 1 and 5 years before. Of the 30 isolates, 14 (46.7%) were recovered from both culture media, one (3.3%) only in Mac Conckey and 15 (50%) only in Yersinia selective agar. Of the 15 isolates recovered in Mac Conckey, 12 (80%) were isolated after 1 week of cold enrichment, 3 (20%) after 2 weeks and none after 3 weeks. Of the 29 isolates recovered in selective Yersinia agar, 22 (75.1%) were isolated after 1 week of cold enrichment, 6 (20.7%) after 2 weeks and 1 (3.4%) after 3 weeks.

Amostras de matérias fecais de 119 búfalos clinicamente sadios, de 5 propriedades, foram colocadas em enriquecimento a 10% em infusão de cérebro e coração por 3 semanas e semeadas semanalmente em meio seletivo para Yersinia spp (Yersinis Selective Agar com Yersinia Antimicrobial Supplement) e em agar Mac Conckey. Yersinia pseudotuberculosis sorotipo Olll foi isolada somente em amostras de uma propriedade em que estava ocorrendo um surto de yersiniose. A bactéria foi recuperada de 21 amostras de um total de 25 amostras de fêmeas adultas sadias e de todas as 9 amostras de bezerros sadios. Y. pseudotuberculosis não foi isolada das demais propriedades, incluindo2 naquelas em que haviam sido diagnosticados surtos de yersiniose 1 e 5 anos antes da coleta. Dos 30 isolamentos, 14 (46,7%) foram isolados nos 2 meios de cultura, 1 (3,3%) somente em agar Mac Conckey e 15 (50%) somente em meio seletivo, demonstrando a maior eficiência deste meio para a identificação de animais portadores. Dos 15 isolamentos obtidos em Mac Conckey, 12 (80%) foram isolados após 1 semana de crioenriquecimento, 3 (20%) após 2 semanas e nenhum após 3 semanas. Dos 29 isolamentos obtidos em meio seletivo, 22 (75,1%) foram isoladosapós 1 semana, 6 (20,7%) após 2 semanas e 1 (3,4%) após 3 semanas.