Thirty-three strains of Brevibacillus laterosporus , including three novel strains isolated from Brazilian soil samples, were examined for genetic variability by the use of different PCR-based methods. Molecular markers that could characterize bacterial strains with regards to their pathogenic potential were investigated. In addition, toxicity was assessed by the use of insects belonging to the orders Lepidoptera and Coleoptera and the mollusk Biomphalaria glabrata . Among the targets tested, Biomphalaria glabrata demonstrated the highest degree of sensitivity to B. laterosporus , with some strains inducing 90 to 100% mortality in snails aged 3 and 12 days posteclosion. Larvae of the coleopteron Anthonomus grandis were also susceptible, presenting mortality levels of between 33 and 63%. Toxicity was also noted towards the lepidopteron Anticarsia gemmatalis . In contrast, no mortality was recorded among test populations of Tenebrio molitor or Spodoptera frugiperda . The application of intergenic transcribed spacer PCR and BOX-PCR generated 15 and 17 different genotypes, respectively. None of the molecular techniques allowed the identification of a convenient marker that was associated with any entomopathogenic phenotype. However, a 1,078-bp amplicon was detected for all strains of B. laterosporus when a primer for amplification of the BOXA1R region was used. Similarly, a 900-bp amplicon was generated from all isolates by use of the primer OPA-11 for randomly amplified polymorphic DNA analysis. These amplicons were not detected for other phenotypically related Brevibacillus species, indicating that they represent markers that are specific for B. laterosporus , which may prove useful for the isolation and identification of new strains of this species.

To perform molecular epidemiology for 113 KPC-producing Klebsiella pneumoniae isolated in 2010 from 12 Brazilian states. The resistance profile was determined by disc diffusion and Etest. Genetic polymorphism was analysed by PFGE and multilocus sequence typing. The genetic environment of the bla_KPC gene was determined by PCR and identification of the carrier plasmid was determined by hybridization. Most of the isolates were multidrug resistant, with 15% and 49% being resistant to polymyxin and tigecycline, respectively. Twenty-two sequence types (STs) were observed, with ST11, ST437 and ST340 [clonal complex 11 (CC11)] being the most prevalent (75% of isolates) observed in 10 states. bla_KPC-2 was associated with transposon Tn4401 ‘b’ and in 36% this gene was found in IncN plasmids of 40 kb. In Brazil, the spread of bla_KPC-2 is occurring due to dispersion of Tn4401 ‘b’, carried by IncN plasmids of 40 kb, and mainly the dissemination of CC11, with ST437 and ST11 playing an important role.

The bacterial community associated with the midgut of three Brazilian Lutzomyia longipalpis (Lutz & Neiva) populations, two from endemic areas for visceral leishmaniasis (Jacobina, Bahia State and São Luís, Maranhão State) and one from a non-endemic area (Lapinha Cave, Minas Gerais State), was identified. Five groups, 35 females each, from each population were separated; a total of 175 females per collecting area were analyzed. The species identification was based on molecular and traditional bacteriological methods. All bacteria were either affiliated to non-Enterobacteriaceae, such as Acinetobacter, Burkholderia, Flavimonas, Pseudomonas and Stenotrophomonas, or and to Enterobacteriaceae, such as Citrobacter, Enterobacter, Escherichia, Klebsiella, Serratia, Pantoea, Morganella and Weeksella. Stenotrophomonas was found to be associated with all three populations studied. In addition, Serratia spp., which are well documented as laboratory contaminant of insects, were detected only in the Jacobina population. We also discuss the impact of the colonization of insect gut by bacteria on the development and transmission of pathogens.

The species Streptococcus dysgalactiae was proposed to accommodate a heterogeneous group of streptococci associated with infections in animals and human beings. This taxon is now considered to include animal isolates of α-haemolytic group C streptococci, previously called S. dysgalactiae; animal and human isolates of β-haemolytic group C streptococci, previously called S. equisimilis 1; β-haemolytic group L strains associated with infections in animals and, rarely, in humans; and β-haemolytic group L strains isolated from humans. DNA-DNA reassociation experiments (hydroxyapatite method) and multilocus enzyme electrophoresis (MEE) were performed on reference strains and clinical isolates to determine the genetic relationships among these different phenotypic categories. DNA-DNA hybridization tests showed that they were related at the species level, despite the phenotypic and host heterogeneity. Both genotypic and phenotypic characterizaton indicated that S. dysgalactiae could be separated into two major sub-groups. The first sub-group contained α-haemolytic strains that showed levels of DNA relatedness with the type strain of S. dysgalactiae ranging from 84 to 90% and from 82 to 88% under optimal (55 °C) and stringent (70 °C) conditions respective. The second sub-group contained β-haemolytic strains showing levels of relatedness ranging from 71 to 79% (55 °C) and from 62 to 73% (70 °C). Percentage divergence varied from 0·5 to 1·0% (α-haemolytic group) and from 2·0 to 3·5% (β-haemolytic group). A dendrogram based on phenotypic similarity between the enzyme bands produced by MEE showed a Jaccard similarity coefficient of 0·45 between the subclusters formed by the two sub-groups. The results of phenotypic and genotypic characterization were consistent with a published proposal to divide S. dysgalactiae into two subspecies, S. dysglactiae subsp. dysgalactiae and S. dysgalactiae subsp. equisimilis, with a few modifications.

This study reveals the presence of different carbapenemase genes ( bla _KPC , bla _NDM , bla _GES , and bla _OXA48-like genes) detected directly from water samples and clonal dispersion (by pulsed-field gel electrophoresis [PFGE] and multilocus sequence typing [MLST]) of KPC-2-producing Enterobacteriaceae in two important urban aquatic matrixes from Rio de Janeiro, Brazil, highlighting the role of aquatic environments as gene pools and the possibility of community spreading.