Whole-Genome Sequence of Francisella noatunensis subsp. orientalis Strain FNO01 Isolated from Diseased Nile Tilapia in Brazil.

This paper describes the complete genome sequence of Francisella noatunensis subsp. orientalis strain FNO01, which was isolated during the first outbreak of francisellosis in cultured Nile tilapia in Brazil. The genome is composed of a circular chromosome with 1,859,830 bp and a G+C content of ~32%.

Complete Genome Sequences of Fish Pathogenic Weissella ceti Strains WS74 and WS105.

We describe here the genome sequencing and annotation of Weissella ceti strains WS74 and WS105, isolated from diseased rainbow trout in Brazil. The two genomes were sequenced with an Ion Torrent personal genome machine (PGM) using a fragment library. The genomes of strains WS74 and WS105 consist of circular chromosomes 1,389,513 bp and 1,390,396 bp long, respectively, both presenting a G+C content of 40.75%.

Whole-Genome Sequence of Weissella ceti Strain WS08, Isolated from Diseased Rainbow Trout in Brazil.

We report here the complete genome sequence of Weissella ceti strain WS08, an emerging pathogen to farm-raised rainbow trout. The genome of strain WS08 is composed of a circular chromosome with 1,355,853 bp and a G+C content of 40.78%.

Immunotherapy of allergic diseases using probiotics or recombinant probiotics.

Allergic diseases affect up to 30% of the western population, and their prevalence is increasing. Probiotics are able to modulate the mucosal immune response, and clinical trials demonstrated that specific strains, especially lactic acid bacteria (LAB) ones, reduce allergic symptoms. Moreover, the use of recombinant probiotics has been evaluated as possible strategies for the immunotherapy of allergic diseases. The production and delivery of allergens by recombinant LAB in concert with their ability to induce a Th1-type immune response have been shown to be a promising mucosal vaccination strategy in mouse model. The aim of this article is to review the applications of probiotics in allergy immunotherapy with a special focus on recombinant LAB delivering proteins or DNA.

Plasticity of Corynebacterium diphtheriae pathogenicity islands revealed by PCR.

Despite the existence of a vaccine against diphtheria, this disease remains endemic and is reemerging in several regions due to many factors, including variations in genes coding for virulence factors. One common feature of virulence factors is their high concentration in pathogenicity islands (PAIs), very unstable regions acquired via horizontal gene transfer, which has lead to the emergence of various bacterial pathogens. The 13 putative PAIs in Corynebacterium diphtheriae NCTC 13129 and the reemergence of this disease point to the great variability in the PAIs of this species, which may reflect on bacterial life style and physiological versatility. We investigated the relationships between the large number of PAIs in C. diphtheriae and the possible implications of their plasticity in virulence. The GenoFrag software was used to design primers to analyze the genome plasticity of two pathogenicity islands of the reference strain (PiCds 3 and 8) in 11 different strains. We found that PiCd 3 was absent in only two strains, showing genes playing putative important roles in virulence and that only one strain harbored PiCd 8, due to its location in a putative "hotspot" for horizontal gene transfer events.

High seroprevalence of caseous lymphadenitis in Brazilian goat herds revealed by Corynebacterium pseudotuberculosis secreted proteins-based ELISA.

We conducted a seroepidemiological survey to determine the prevalence of caseous lymphadenitis (CLA) in goat herds in Minas Gerais state, Brazil. Serum samples were collected from goats (n=676) from 108 rural properties in 2001, covering most of the sub-regions of this ca. 586,500 square kilometer state. Antibodies against Corynebacterium pseudotuberculosis secreted proteins were detected by an indirect enzyme-linked immunosorbent assay (ELISA). Most of the animals (78.9%) tested positive for CLA; 98% of flocks presented at least one seropositive animal. Goats managed under an extensive production system had a significantly higher seroprevalence of CLA than those in intensive and semi-intensive operations. The age distribution of the animals in the flocks affected the prevalence of this disease; however, goat breed did not. We found seropositivity against C. pseudotuberculosis to be highly prevalent in these Brazilian goat herds; consequently, appropriate management practices for the control of CLA should be implemented.

A description of genes of Corynebacterium pseudotuberculosis useful in diagnostics and vaccine applications.

Corynebacterium pseudotuberculosis, a Gram-positive intracellular pathogen, is the etiological agent of caseous lymphadenitis or CLA. This bacterium infects goats and sheep and causes great economic losses worldwide annually, mainly for goat producers. Despite its importance, CLA is still poorly characterized. However, with advances in the genomic field, many C. pseudotuberculosis genes have already been characterized, mainly those related to virulence such as phospholipase D. Here, we examined the use of the several available genes of C. pseudotuberculosis and reviewed their applications in vaccine construction, more efficient diagnostics for CLA, and control of this disease, among other applications.

A description of genes of Corynebacterium pseudotuberculosis useful in diagnostics and vaccine applications

Corynebacterium pseudotuberculosis, a Gram-positive intracellular pathogen, is the etiological agent of caseous lymphadenitis or CLA. This bacterium infects goats and sheep and causes great economic losses worldwide annually, mainly for goat producers. Despite its importance, CLA is still poorly characterized. However, with advances in the genomic field, many C. pseudotuberculosis genes have already been characterized, mainly those related to virulence such as phospholipase D. Here, we examined the use of the several available genes of C. pseudotuberculosis and reviewed their applications in vaccine construction, more efficient diagnostics for CLA, and control of this disease, among other applications.

Construction and partial characterization of a Corynebacterium pseudotuberculosis bacterial artificial chromosome library through genomic survey sequencing.

Corynebacterium pseudotuberculosis is a gram-positive bacterium that causes caseous lymphadenitis in sheep and goats. However, despite the economic losses caused by caseous lymphadenitis, there is little information about the molecular mechanisms of pathogenesis of this bacterium. Genomic libraries constructed in bacterial artificial chromosome (BAC) vectors have become the method of choice for clone development in high-throughput genomic-sequencing projects. Large-insert DNA libraries are useful for isolation and characterization of important genomic regions and genes. In order to identify targets that might be useful for genome sequencing, we constructed a C. pseudotuberculosis BAC library in the vector pBeloBAC11. This library contains about 18,000 BAC clones, with inserts ranging in size from 25 to 120 kb, theoretically representing a 390-fold coverage of the C. pseudotuberculosis genome (estimated to be 2.5-3.1 Mb). Many genomic survey sequences (GSSs) with homology to C. diphtheriae, C. glutamicum, C. efficiens, and C. jeikeium proteins were observed within a sample of 215 sequenced clones, confirming their close phylogenetic relationship. Computer analyses of GSSs did not detect chimeric, deleted, or rearranged BAC clones, showing that this library has low redundancy. This GSSs collection is now available for further genetic and physical analysis of the C. pseudotuberculosis genome. The GSS strategy that we used to develop our library proved to be efficient for the identification of genes and will be an important tool for mapping, assembly, comparative, and functional genomic studies in a C. pseudotuberculosis genome sequencing project that will begin this year.

An improved protocol for electrotransformation of Corynebacterium pseudotuberculosis.

We developed an improved protocol for the electrotransformation of Corynebacterium pseudotuberculosis, testing variations of parameters in the procedures that are routinely used for the preparation of electrocompetent cells of this species, including (i) culture conditions, (ii) cell growth phase, (iii) electroporation solutions and (iv) quantity of plasmid DNA. We obtained the greatest efficiency of transformation when the cells were grown until the stationary phase and then washed with 10% glycerol electroporation solution. The transformation efficiency was inversely proportional to the quantity of plasmid DNA. The transformation efficiency reached 10(5) colony-forming units (cfu)/mug plasmid DNA. This protocol would be useful for genetic studies of C. pseudotuberculosis.

Construction and partial characterization of a Corynebacterium pseudotuberculosis bacterial artificial chromosome library through genomic survey sequencing

Corynebacterium pseudotuberculosis is a gram-positive bacterium that causes caseous lymphadenitis in sheep and goats. However, despite the economic losses caused by caseous lymphadenitis, there is little information about the molecular mechanisms of pathogenesis of this bacterium. Genomic libraries constructed in bacterial artificial chromosome (BAC) vectors have become the method of choice for clone development in high-throughput genomic-sequencing projects. Large-insert DNA libraries are useful for isolation and characterization of important genomic regions and genes. In order to identify targets that might be useful for genome sequencing, we constructed a C. pseudotuberculosis BAC library in the vector pBeloBAC11. This library contains about 18,000 BAC clones, with inserts ranging in size from 25 to 120 kb, theoretically representing a 390-fold coverage of the C. pseudotuberculosis genome (estimated to be 2.5-3.1 Mb). Many genomic survey sequences (GSSs) with homology to C. diphtheriae, C. glutamicum, C. efficiens, and C. jeikeium proteins were observed within a sample of 215 sequenced clones, confirming their close phylogenetic relationship. Computer analyses of GSSs did not detect chimeric, deleted, or rearranged BAC clones, showing that this library has low redundancy. This GSSs collection is now available for further genetic and physical analysis of the C. pseudotuberculosis genome. The GSS strategy that we used to develop our library proved to be efficient for the identification of genes and will be an important tool for mapping, assembly, comparative, and functional genomic studies in a C. pseudotuberculosis genome sequencing project that will begin this year.

Update of microbial genome programs for bacteria and archaea

Since the Haemophilus influenzae genome sequence was completed in 1995, 172 other prokaryotic genomes have been completely sequenced, while 508 projects are underway. Besides pathogens, organisms important in several other fields, such as biotechnology and bioremediation, have also been sequenced. Institutions choose the organisms they wish to sequence according to the importance that these species represent to them, the availability of the microbes, and based on the similarity of a species of interest with others that have been sequenced previously. Improvements in sequencing techniques and in associated methodologies have been achieved; however, scientists need to continue working on the development of this field. In Brazil, a multicentered, centrally coordinated and research-focused network was adopted and successfully used for the sequencing of several important organisms. We analyzed the current status of microbial genomes, the trends for criteria used to choose new sequencing projects, the future of microbial sequencing, and the Brazilian genome network.