Whole-genome optical mapping reveals a mis-assembly between two rRNA operons of Corynebacterium pseudotuberculosis strain 1002.

BACKGROUND: Studies have detected mis-assemblies in genomes of the species Corynebacterium pseudotuberculosis. These new discover have been possible due to the evolution of the Next-Generation Sequencing platforms, which have provided sequencing with accuracy and reduced costs. In addition, the improving of techniques for construction of high accuracy genomic maps, for example, Whole-genome mapping (WGM) (OpGen Inc), have allow high-resolution assembly that can detect large rearrangements. RESULTS: In this work, we present the resequencing of Corynebacterium pseudotuberculosis strain 1002 (Cp1002). Cp1002 was the first strain of this species sequenced in Brazil, and its genome has been used as model for several studies in silico of caseous lymphadenitis disease. The sequencing was performed using the platform Ion PGM and fragment library (200 bp kit). A restriction map was constructed, using the technique of WGM with the enzyme KpnI. After the new assembly process, using WGM as scaffolder, we detected a large inversion with size bigger than one-half of genome. A specific analysis using BLAST and NR database shows that the inversion occurs between two homology RNA ribosomal regions. CONCLUSION: In conclusion, the results showed by WGM could be used to detect mismatches in assemblies, providing genomic maps with high resolution and allow assemblies with more accuracy and completeness. The new assembly of C. pseudotuberculosis was deposited in GenBank under the accession no. CP012837.

Differential transcriptional profile of Corynebacterium pseudotuberculosis in response to abiotic stresses.

BACKGROUND: The completion of whole-genome sequencing for Corynebacterium pseudotuberculosis strain 1002 has contributed to major advances in research aimed at understanding the biology of this microorganism. This bacterium causes significant loss to goat and sheep farmers because it is the causal agent of the infectious disease caseous lymphadenitis, which may lead to outcomes ranging from skin injury to animal death. In the current study, we simulated the conditions experienced by the bacteria during host infection. By sequencing transcripts using the SOLiDTM 3 Plus platform, we identified new targets expected to potentiate the survival and replication of the pathogen in adverse environments. These results may also identify possible candidates useful for the development of vaccines, diagnostic kits or therapies aimed at the reduction of losses in agribusiness. RESULTS: Under the 3 simulated conditions (acid, osmotic and thermal shock stresses), 474 differentially expressed genes exhibiting at least a 2-fold change in expression levels were identified. Important genes to the infection process were induced, such as those involved in virulence, defence against oxidative stress, adhesion and regulation, and many genes encoded hypothetical proteins, indicating that further investigation of the bacterium is necessary. The data will contribute to a better understanding of the biology of C. pseudotuberculosis and to studies investigating strategies to control the disease. CONCLUSIONS: Despite the veterinary importance of C. pseudotuberculosis, the bacterium is poorly characterised; therefore, effective treatments for caseous lymphadenitis have been difficult to establish. Through the use of RNAseq, these results provide a better biological understanding of this bacterium, shed light on the most likely survival mechanisms used by this microorganism in adverse environments and identify candidates that may help reduce or even eradicate the problems caused by this disease.

Ion Torrent-based transcriptional assessment of a Corynebacterium pseudotuberculosis equi strain reveals denaturing high-performance liquid chromatography a promising rRNA depletion method.

Corynebacterium pseudotuberculosis equi is a Gram-positive pathogenic bacterium which affects a variety of hosts. Besides the great economic losses it causes to horse-breeders, this organism is also known to be an important infectious agent to cattle and buffaloes. As an outcome of the efforts in characterizing the molecular basis of its virulence, several complete genome sequences were made available in recent years, enabling the large-scale assessment of genes throughout distinct isolates. Meanwhile, the RNA-seq stood out as the technology of choice for comprehensive transcriptome studies, which may bring valuable information regarding active genomic regions, despite of the still impeditive associated costs. In an attempt to increase the use of generated reads per instrument run, by effectively eliminating unwanted rRNAs from total RNA samples without relying on any commercially available kits, we applied denaturing high-performance liquid chromatography (DHPLC) as an alternative method to assess the transcriptional profile of C. pseudotuberculosis. We have found that the DHPLC depletion method, allied to Ion Torrent sequencing, allows mapping of transcripts in a comprehensive way and identifying novel transcripts when a de novo approach is used. These data encourage us to use DHPLC in future transcriptional evaluations in C. pseudotuberculosis.

Genome sequence of the Corynebacterium pseudotuberculosis Cp316 strain, isolated from the abscess of a Californian horse.

The bacterium Corynebacterium pseudotuberculosis is of major veterinary importance because it affects livestock, particularly sheep, goats, and horses, in several countries, including Australia, Brazil, the United States, and Canada, resulting in significant economic losses. In the present study, we describe the complete genome of the Corynebacterium pseudotuberculosis Cp316 strain, biovar equi, isolated from the abscess of a North American horse.

Genome sequence of Exiguobacterium antarcticum B7, isolated from a biofilm in Ginger Lake, King George Island, Antarctica.

Exiguobacterium antarcticum is a psychotropic bacterium isolated for the first time from microbial mats of Lake Fryxell in Antarctica. Many organisms of the genus Exiguobacterium are extremophiles and have properties of biotechnological interest, e.g., the capacity to adapt to cold, which make this genus a target for discovering new enzymes, such as lipases and proteases, in addition to improving our understanding of the mechanisms of adaptation and survival at low temperatures. This study presents the genome of E. antarcticum B7, isolated from a biofilm sample of Ginger Lake on King George Island, Antarctic peninsula.

Whole-genome sequence of Corynebacterium pseudotuberculosis strain Cp162, isolated from camel.

Corynebacterium pseudotuberculosis is a pathogen of great veterinary and economic importance, since it affects livestock, mainly sheep and goats, worldwide, together with reports of its presence in camels in several Arabic, Asiatic, and East and West African countries, as well as Australia. In this article, we report the genome sequence of Corynebacterium pseudotuberculosis strain Cp162, collected from the external neck abscess of a camel in the United Kingdom.

Complete genome sequence of Corynebacterium pseudotuberculosis strain Cp267, isolated from a llama.

In this work we report the genome of Corynebacterium pseudotuberculosis strain 267, isolated from a llama. This pathogen is of great veterinary and economic importance, as it is the cause of caseous lymphadenitis in several livestock species around the world and causes significant losses due to the high cost of treatment.

The core stimulon of Corynebacterium pseudotuberculosis strain 1002 identified using ab initio methodologies.

Corynebacterium pseudotuberculosis is a bacterium which causes diseases such as caseous lymphadenitis in small ruminants, resulting in large-scale economic losses for agribusiness worldwide. Consequently, this bacterium including its transcriptional profile analysis has been the focus of various studies. Identification of the transcripts that appear under conditions that simulate the environment encountered by this bacterial species in the host is of great importance in discovering new targets for the production of more efficient vaccines. We sequenced the cDNA of Corynebacterium pseudotuberculosis strain 1002, using the SOLiD V3 system, under the following conditions: osmotic stress (2 M), acidity (pH), heat shock (50 °C) and control condition (N). To identify the transcripts shared among the stimulons and integrate this information with the results from BLAST and BLAST2GO, we developed the software CoreStImulon (CSI) which allows the user to individually distinguish the genes in terms of their participation in biological processes, their function and cellular location. In the biosynthetic processes, eleven genes represented in the core stimulon and twenty genes in the control were observed. This validates the hypothesis that the organisms strategy for surviving in a hostile environment is through growth reduction. The oxidation reduction process, response to stress process, and cell adhesion are controlled by genes that contribute to bacterial cell maintenance under stress conditions; these could be involved in their pathogenicity. The methodology for identification of transcripts obtained by ab initio assembly and shared among the stimulons permitted candidates selection for vaccine studies. CSI is available at https://sourceforge.net/projects/corestimulon/.

Complete genome sequence of Corynebacterium pseudotuberculosis biovar ovis strain P54B96 isolated from antelope in South Africa obtained by rapid next generation sequencing technology.

The Actinobacteria, Corynebacterium pseudotuberculosis strain P54B96, a nonmotile, non-sporulating and a mesophile bacterium, was isolated from liver, lung and mediastinal lymph node lesions in an antelope from South Africa. This strain is interesting in the sense that it has been found together with non-tuberculous mycobacteria (NTMs) which could nevertheless play a role in the lesion formation. In this work, we describe a set of features of C. pseudotuberculosis P54B96, together with the details of the complete genome sequence and annotation. The genome comprises of 2.34 Mbp long, single circular genome with 2,084 protein-coding genes, 12 rRNA, 49 tRNA and 62 pseudogenes and a G+C content of 52.19%. The analysis of the genome sequence provides means to better understanding the molecular and genetic basis of virulence of this bacterium, enabling a detailed investigation of its pathogenesis.

Complete genome sequence of Corynebacterium pseudotuberculosis strain CIP 52.97, isolated from a horse in Kenya.

In this work, we report the whole-genome sequence of Corynebacterium pseudotuberculosis bv. equi strain CIP 52.97 (Collection Institut Pasteur), isolated in 1952 from a case of ulcerative lymphangitis in a Kenyan horse, which has evidently caused significant losses to agribusiness. Therefore, obtaining this genome will allow the detection of important targets for postgenomic studies, with the aim of minimizing problems caused by this microorganism.

Whole-genome sequence of Corynebacterium pseudotuberculosis PAT10 strain isolated from sheep in Patagonia, Argentina.

In this work, we report the complete genome sequence of a Corynebacterium pseudotuberculosis PAT10 isolate, collected from a lung abscess in an Argentine sheep in Patagonia, whose pathogen also required an investigation of its pathogenesis. Thus, the analysis of the genome sequence offers a means to better understanding of the molecular and genetic basis of virulence of this bacterium.