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author:("seifert, nbia")
1.  Progression of ‘OMICS’ methodologies for understanding the pathogenicity of Corynebacterium pseudotuberculosis: the Brazilian experience 
Since the first successful attempt at sequencing the Corynebacterium pseudotuberculosis genome, large amounts of genomic, transcriptomic and proteomic data have been generated. C. pseudotuberculosis is an interesting bacterium due to its great zoonotic potential and because it causes considerable economic losses worldwide. Furthermore, different strains of C. pseudotuberculosis are capable of causing various diseases in different hosts. Currently, we seek information about the phylogenetic relationships between different strains of C. pseudotuberculosis isolates from different hosts across the world and to employ these data to develop tools to diagnose and eradicate the diseases these strains cause. In this review, we present the latest findings on C. pseudotuberculosis that have been obtained with the most advanced techniques for sequencing and genomic organization. We also discuss the development of in silico tools for processing these data to prompt a better understanding of this pathogen.
doi:10.5936/csbj.201303013
PMCID: PMC3962224
Corynebacterium pseudotuberculosis; SOLiD next generation sequencing; Ion Torrent next generation sequencing; SDS-PAGE; mass spectrometry; RNA-seq
2.  High sero-prevalence of caseous lymphadenitis identified in slaughterhouse samples as a consequence of deficiencies in sheep farm management in the state of Minas Gerais, Brazil 
Background
Caseous lymphadenitis (CLA), caused by Corynebacterium pseudotuberculosis, is one of the most important diseases of sheep and goats, causing considerable economic losses for herd owners.
Results
We assessed the seroprevalence of infection with C. pseudotuberculosis in 805 sheep from 23 sheep farms that supply slaughterhouses in the state of Minas Gerais; we also analyzed management practices that could be associated with CLA occurrence, used on these and nearby farms that also supplied animals to the slaughterhouse (n = 60). The serum samples for assaying CLA infection were taken at the slaughterhouse. Frequency of infection with C. pseudotuberculosis was estimated at 43.7%, and farm frequency was estimated at 100%. Management practices were analyzed through a questionnaire. All farmers (60/60) had extensive/semi-extensive rearing system; 70.0% (42/60) identified sheep individually; 11.7% (7/60) had periodical technical assistance; 41.7% (25/60) disinfected the facilities; 86.7% (52/60) used barbed wire fences and did not implement adequate CLA control measures; only 11.7% (7/60) of breeders reported vaccination against C. pseudotuberculosis; 13.3% (8/60) took note of animals with clinical signs of CLA; 1.7% (1/60) opened and sanitized abscesses, and isolated the infected animals; 10.0% (6/60) knew the zoonotic potential of this disease and 1.7% (1/60) of the farmers culled animals in case of recurrence of abscesses.
Conclusions
It can be concluded that C. pseudotuberculosis infection is widely spread in sheep flocks in Minas Gerais state in Brazil and that there is a lack of good management measures and vaccination, allowing transmission of this infectious agent throughout the production network.
doi:10.1186/1746-6148-7-68
PMCID: PMC3256107  PMID: 22067701
Caseous lymphadenitis; Corynebacterium pseudotuberculosis; sheep; slaughterhouse; Minas Gerais
3.  Evidence for Reductive Genome Evolution and Lateral Acquisition of Virulence Functions in Two Corynebacterium pseudotuberculosis Strains 
PLoS ONE  2011;6(4):e18551.
Background
Corynebacterium pseudotuberculosis, a Gram-positive, facultative intracellular pathogen, is the etiologic agent of the disease known as caseous lymphadenitis (CL). CL mainly affects small ruminants, such as goats and sheep; it also causes infections in humans, though rarely. This species is distributed worldwide, but it has the most serious economic impact in Oceania, Africa and South America. Although C. pseudotuberculosis causes major health and productivity problems for livestock, little is known about the molecular basis of its pathogenicity.
Methodology and Findings
We characterized two C. pseudotuberculosis genomes (Cp1002, isolated from goats; and CpC231, isolated from sheep). Analysis of the predicted genomes showed high similarity in genomic architecture, gene content and genetic order. When C. pseudotuberculosis was compared with other Corynebacterium species, it became evident that this pathogenic species has lost numerous genes, resulting in one of the smallest genomes in the genus. Other differences that could be part of the adaptation to pathogenicity include a lower GC content, of about 52%, and a reduced gene repertoire. The C. pseudotuberculosis genome also includes seven putative pathogenicity islands, which contain several classical virulence factors, including genes for fimbrial subunits, adhesion factors, iron uptake and secreted toxins. Additionally, all of the virulence factors in the islands have characteristics that indicate horizontal transfer.
Conclusions
These particular genome characteristics of C. pseudotuberculosis, as well as its acquired virulence factors in pathogenicity islands, provide evidence of its lifestyle and of the pathogenicity pathways used by this pathogen in the infection process. All genomes cited in this study are available in the NCBI Genbank database (http://www.ncbi.nlm.nih.gov/genbank/) under accession numbers CP001809 and CP001829.
doi:10.1371/journal.pone.0018551
PMCID: PMC3078919  PMID: 21533164
4.  A combined approach for comparative exoproteome analysis of Corynebacterium pseudotuberculosis 
BMC Microbiology  2011;11:12.
Background
Bacterial exported proteins represent key components of the host-pathogen interplay. Hence, we sought to implement a combined approach for characterizing the entire exoproteome of the pathogenic bacterium Corynebacterium pseudotuberculosis, the etiological agent of caseous lymphadenitis (CLA) in sheep and goats.
Results
An optimized protocol of three-phase partitioning (TPP) was used to obtain the C. pseudotuberculosis exoproteins, and a newly introduced method of data-independent MS acquisition (LC-MSE) was employed for protein identification and label-free quantification. Additionally, the recently developed tool SurfG+ was used for in silico prediction of sub-cellular localization of the identified proteins. In total, 93 different extracellular proteins of C. pseudotuberculosis were identified with high confidence by this strategy; 44 proteins were commonly identified in two different strains, isolated from distinct hosts, then composing a core C. pseudotuberculosis exoproteome. Analysis with the SurfG+ tool showed that more than 75% (70/93) of the identified proteins could be predicted as containing signals for active exportation. Moreover, evidence could be found for probable non-classical export of most of the remaining proteins.
Conclusions
Comparative analyses of the exoproteomes of two C. pseudotuberculosis strains, in addition to comparison with other experimentally determined corynebacterial exoproteomes, were helpful to gain novel insights into the contribution of the exported proteins in the virulence of this bacterium. The results presented here compose the most comprehensive coverage of the exoproteome of a corynebacterial species so far.
doi:10.1186/1471-2180-11-12
PMCID: PMC3025830  PMID: 21241507
5.  CHARACTERIZATION OF VIRULENCE OF Leptospira ISOLATES IN A HAMSTER MODEL 
Vaccine  2008;26(31):3892-3896.
Effort has been made to identify protective antigens in order to develop a recombinant vaccine against leptospirosis. Several attempts failed to conclusively demonstrate efficacy of vaccine candidates due to the lack of an appropriate model of lethal leptospirosis. The purposes of our study were: (i) to test the virulence of leptospiral isolates from Brazil, which are representative of important serogroups that cause disease in humans and animals; and (ii) to standardize the lethal dose 50% (LD50) for each of the virulent strains using a hamster (Mesocricetus auratus) model. Five of seven Brazilian isolates induced lethality in a hamster model, with inocula lower than 200 leptospires. Histopathological examination of infected animals showed typical lesions found in both natural and experimental leptospirosis. Results described here demonstrated the potential use of Brazilian isolates as highly virulent strains in challenge experiments using hamster as an appropriate animal model for leptospirosis. Furthermore these strains may be useful in heterologous challenge studies which aim to evaluate cross-protective responses induced by subunit vaccine candidates.
doi:10.1016/j.vaccine.2008.04.085
PMCID: PMC2519131  PMID: 18547690
Leptospira; leptospirosis; lethal dose; isolation; animal model; virulence
6.  Serum antileptospiral agglutinins in freshwater turtles from Southern Brazil 
Brazilian Journal of Microbiology  2009;40(2):227-230.
In this study, we observed the presence of antileptospiral agglutinins in freshwater turtles of two urban lakes of Pelotas, Southern Brazil. Forty animals (29 Trachemys dorbigny and 11 Phrynops hilarii) were captured and studied. Attempts to isolate leptospires from blood and urine samples were unsuccessful. Serum samples (titer > 100) reactive to pathogenic strains were observed in 11 animals. These data encourage surveys of pet turtles to evaluate the risk of transmission of pathogenic leptospires to humans.
doi:10.1590/S1517-83822009000200003
PMCID: PMC3769731  PMID: 24031348
Leptospirosis; Turtles; Agglutinins
7.  Leptospira noguchii and Human and Animal Leptospirosis, Southern Brazil 
Emerging Infectious Diseases  2009;15(4):621-623.
doi:10.3201/eid1504.071669
PMCID: PMC2671420  PMID: 19331754
Zoonoses; Leptospira noguchii; leptospirosis; isolation; taxonomy; letter
8.  Isolation of Leptospira noguchii from sheep 
Veterinary microbiology  2006;121(1-2):144-149.
The main goal of this study was to obtain new isolates of Leptospira spp. from sheep. A total of ten kidney samples and 44 blood samples were collected from sheep slaughtered in Pelotas, Southern Brazil. One isolate was obtained which was identified by 16S rRNA gene sequencing and serogrouping to be Leptospira noguchii serogroup Autumnalis. Microscopic agglutination test (MAT) evaluation revealed that 4.5% of the sheep sera reacted against the Autumnalis serogroup. This is the first report of isolation of L. noguchii from sheep. Together these findings indicate that L. noguchii infections may be a potentially important veterinary problem in this domestic animal species.
doi:10.1016/j.vetmic.2006.11.010
PMCID: PMC1868676  PMID: 17222993
leptospirosis; Leptospira noguchii; isolation; serogrouping; sheep; Brazil

Results 1-8 (8)