M Picardeau

..Thus, this new Escherichia coli-mycobacteria shuttle vector may be used in both slow- and fast-growing mycobacteria and in co-transformation experiments with other mycobacterial vectors...

..interrogans virulent strains. This genomic island, containing a high proportion of novel genes, may have an important role in spreading genes, including virulence factors, among bacterial populations...

..Heme is typically a major iron source for bacteria, but little is known about how bacteria of the Leptospira genus, composed of both saprophytic and pathogenic species, access heme...

..These results show that ChpK possesses a broad activity against both prokaryotes and eukaryotes, suggesting that the cellular target of the toxin is conserved in these organisms...

..Our results demonstrate that FlaB is involved in flagella assembly and motility. They also show the feasibility of performing allelic replacement in Leptospira spp. by homologous recombination...

..Here, we describe a system for heterologous expression of the Leptospira interrogans genes ligA and ligB in the saprophyte Leptospira biflexa serovar Patoc...

..The coexpression of ChpI neutralizes ChpK toxicity. By Southern blot analysis, chp homologs were found in all representative pathogenic strains of L. interrogans...

..In addition, a L. interrogans gene, called metZ, was found to complement an Escherichia coli metB mutant, further suggesting that the transsulfuration pathway is also present in Leptospira spp...

..interrogans, respectively. Analysis of mutants indicated that transposition occurs randomly, and at single sites in the genome of these strains, allowing the utilization of this system to generate libraries of transposon mutants...

..Functional analysis of these ORFs suggests that they probably carry out similar maintenance roles in pCLP...

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..This may have implications in a better understanding of the pathogenesis of Leptospira...

..Our data indicate that the replicon derived from the LE1 leptophage, together with the kanamycin resistance gene, is a promising tool with which to develop the genetics of Leptospira species...

..biflexa. Comparative genomics, in combination with gene inactivation, gives us significant functional information on iron homeostasis in Leptospira spp...

..The genome sequence flanking the erp gene includes cell-wall-related ORFs and displays extensive conservation between saprophytic and pathogenic mycobacteria...

..These results confirm the importance of iron for the growth of Leptospira and its ability to use multiple iron sources...

..biflexa has been developed. These studies enable the use of L. biflexa as a model bacterium among spirochetes...

..These results are essential for the improvement of current diagnostic tools and provide a starting point for a better understanding of the epidemiology of leptospirosis in this area of endemicity...

..Transposon-based approaches greatly facilitate studies of bacterial biology. We summarize the current mariner-based transposon tools and techniques for conducting genetic studies in bacteria...

..The authors have also characterized a second selectable marker that allows the construction of a spectinomycin-resistant L. meyeri-E. coli shuttle vector and the functional complementation of the L. meyeri trpE mutant...

..interrogans. This rapid and easy method should greatly contribute to a better knowledge of the epidemiology of Leptospira...

..interrogans mutants. This approach of transposon mutagenesis will be useful for understanding the spirochetal physiology and the pathogenic mechanisms of Leptospira, which remain largely unknown...

..These results provide the first insight into a unique DNA binding filament-forming coiled-coil protein that could play an important role in the subcellular architecture of the spirochetal microorganism...

..e., DNA is condensed at the midcell. Our data indicate that L. biflexa RecA plays a major role in ensuring cell viability via mechanisms such as DNA repair and, indirectly, active chromosome partitioning...

..To date, Leptospira isolates have never been isolated in this endemic region...

..qPCR will be used in future studies to evaluate the efficacy of vaccine candidates against leptospirosis and the virulence of selected L. interrogans mutants relative to the parental strain...

..We also generated a gentamicin resistance cassette that allows the use of a third selectable marker in leptospires. These results may facilitate further advances in gene transfer systems in Leptospira spp...

..Loa22 is therefore necessary for virulence of L. interrogans in the animal model and represents, to our knowledge, the first genetically defined virulence factor in Leptospira species...

..Finally, we showed that GFP can be used as a reporter to assess promoter activity in different environmental conditions. These results may facilitate further advances for studying the genetics of Leptospira spp...

..Our results show that this simple PCR-based MLVA typing technique is a powerful methodology for the epidemiology of leptospirosis...

..The formation of such a biofilm is consistent with the life of saprophytic strains in water and may help pathogenic strains to survive in environmental habitats and to colonize the host...

..These results enable the construction of new shuttle vectors for studying the genetics of Leptospira spp. This study will also contribute to a better knowledge of phages unrelated to lambdoid phages...

..borgpetersenii has impaired its survival outside a mammalian host, whereas L. interrogans has retained environmental sensory functions that facilitate disease transmission through water...

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