First Identification of bla NDM-1 Producing Escherichia coli ST 9499 Isolated from Musca domestica in the Urban Center of Rio de Janeiro, Brazil.

The present study presents phenotypic and molecular characterization of a multidrug-resistant strain of Escherichia coli (Lemef26), belonging to sequence type ST9499 carrying a blaNDM-1 carbapenem resistance gene. The bacterium was isolated from a specimen of Musca domestica, collected in proximity to a hospital in Rio de Janeiro City, Brazil. The strain was identified as E. coli by matrix-assisted laser desorption-ionization time of flight mass spectrometry (Maldi-TOF-MS) and via genotypic analysis (Whole-Genome Sequencing-WGS), followed by phylogenetic analysis, antibiotic resistance profiling (using phenotypic and genotypic methods) and virulence genotyping. Interestingly, the blaNDM-1 was the only resistance determinant detected using a panel of common resistance genes, as evaluated by PCR. In contrast, WGS detected genes conferring resistance to aminoglycosides, fluoroquinolones, quinolones, trimethoprim, beta-lactams, chloramphenicol, macrolides, sulfonamide, tetracycline, lincosamide and streptogramin B. Conjugation experiments demonstrated the transfer of carbapenem resistance, via acquisition of the blaNDM-1 sequence, to a sensitive receptor strain of E. coli, indicating that blaNDM-1 is located on a conjugative plasmid (most likely of the IncA/C incompatibility group, in association with the transposon Tn3000). Phylogenetic analyses placed Lemef26 within a clade of strains exhibiting allelic and environment diversity, with the greatest level of relatedness recorded with a strain isolated from a human source suggesting a possible anthropogenic origin. Analysis of the virulome revealed the presence of fimbrial and pilus genes, including a CFA/I fimbriae (cfaABCDE), common pilus (ecpABCDER), laminin-bind fimbrae (elfADG), hemorrhagic pilus (hcpABC) and fimbrial adherence determinants (stjC) indicates the ability of strain Lemef26 to colonize animal hosts. To the best of our knowledge, this study represents the first report of blaNDM-1 carbapenemase gene in an E. coli strain isolated from M. domestica. In concordance with the findings of previous studies on the carriage of MDR bacteria by flies, the data presented herein provide support to the idea that flies may represent a convenient means (as sentinel animals) for the monitoring of environmental contamination with multidrug-resistant bacteria.

Bioactivity under laboratory conditions of Brevibacillus laterosporus towards larvae and adults of Chrysomya putoria (Diptera: Calliphoridae).

Brevibacillus laterosporus was tested for entomopathogenic activity towards larvae and adults of Chrysomya putoria (Diptera: Calliphoridae) under laboratory conditions. Sublethal effects related to feeding activity or development were observed, including reduction in larval weight gain, probably by inhibition of feeding, and variation in the duration of the developmental stages of the insect. Larval mortality was dose dependent following ingestion. The experiments were performed with newly emerged adults exposed to a sugar based diet containing spore suspensions. Concentrations of 1.13 × 109 CFU/ml caused 70.5% of mortality. The present study highlights the potential of B. laterosporus to control populations of C. putoria, a dipteran of medical-veterinary and sanitary importance, both in larval and adult stages.

Laboratory evaluation of Brevibacillus laterosporus strains as biocidal agents against Chrysomya megacephala (Fabricius, 1794) (Diptera: Calliphoridae) larvae.

The biocidal activity of three strains of Brevibacillus laterosporus upon the post-embryonic developmental stages of Chrysomya megacephala was evaluated. Bioassays were performed to verify lethal and sub-lethal effects including ultra-structural changes in the midgut. Among the strains assayed, Shi3 presented the highest larval mortality rates, achieving 70% at a concentration of 1×108 spores/g of diet. Transmission electron microscopy revealed intestinal alterations caused by all strains tested. The findings of this study indicate that Shi3 represents a promising tool for use in the biocontrol of C. megacephala.

Detection of Carbapenemase Genes in Aquatic Environments in Rio de Janeiro, Brazil.

This study reveals the presence of different carbapenemase genes (blaKPC, blaNDM, blaGES, and blaOXA48-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.

Larvicidal activity and effects on post embrionary development of laboratory reared Musca domestica (Linnaeus, 1758) (Diptera: Muscidae), treated with Brevibacillus laterosporus (Laubach) spore suspensions.

The application of a spore suspension of Brevibacillus laterosporus (Laubach) (strain Bon707), at a concentration of 1.94×10(9)CFU/mL in the diet, induced a level of 70% mortality in larvae of Musca domestica. No sublethal effects, upon feeding activity or development were recorded. However, electron microscopic examination of the digestive tract of larvae fed with B. laterosporus, revealed cellular vacuolization and cytoplasmic disorganization.

Evaluation of larvicidal activity and effects on post embrionary development of laboratory reared Lucilia cuprina (Wiedemann, 1830) (Diptera: Calliphoridae), treated with Brevibacillus laterosporus.

The blowfly Lucilia cuprina is an economically important livestock pest that is also associated with human myiasis. To date, methods including the application of chemical pesticides, plant extracts, insect growth regulators and a range of Bacillus thuringiensis strains have been used, with varying degrees of success, to control this pest. The present study evaluated the larvicidal activity and the induction of sub lethal effects upon post embrionary development following ingestion of 12 strains of Brevibacillus laterosporus, presented individually in the diet as spores. All strains were shown to be larvicidal, with corrected mortality levels of 29 to 54%. No significant differences were observed, in terms of larval weight at the time of abandoning the diet, in the time taken for the initiation of the pupation process, in the duration of the pupation process, the period of adult emergence or cumulative mortality during the transition from larvae to adult. However, an influence upon sex ratio was observed. This study suggests that strains of B. laterosporus hold potential for development as a tool in the biological control of L. cuprina.

Characterization by MALDI-TOF MS and 16S rRNA Gene Sequencing of Aerobic Endospore-Forming Bacteria Isolated from Pharmaceutical Facility in Rio de Janeiro, Brazil.

Bacillus and related genera are among the most important contaminants in the pharmaceutical production environment, and the identification of these microorganisms at the species level assists in the investigation of sources of contamination and in preventive and corrective decision making. The aim of this study was to evaluate three methodologies for the characterization of endospore-forming aerobic bacterial strains isolated from a pharmaceutical unit in Rio de Janeiro, Brazil. MALDI-TOF MS was performed using MALDI Biotyper® and VITEK® MS RUO systems, and complete 16S rRNA gene sequencing was performed using the Sanger methodology. The results showed the prevalence of the genera Bacillus (n = 9; 36.0%), Priestia (n = 5; 20.0%), and Paenibacillus (n = 4; 16.0%). Three (20.0%) strains showed <98.7% of DNA sequencing similarity on the EzBioCloud Database, indicating possible new species. In addition, the reclassification of Bacillus pseudoflexus to the genus Priestia as Priestia pseudoflexus sp. nov. is proposed. In conclusion, 16S rRNA and MALDI TOF/MS were not sufficient to identify all strains at the species level, and complementary analyses were necessary.

Update of the molecular epidemiology of KPC-2-producing Klebsiella pneumoniae in Brazil: spread of clonal complex 11 (ST11, ST437 and ST340).

OBJECTIVES: To perform molecular epidemiology for 113 KPC-producing Klebsiella pneumoniae isolated in 2010 from 12 Brazilian states. METHODS: 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. RESULTS: 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. CONCLUSIONS: 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.

Extended genetic analysis of Brazilian isolates of Bacillus cereus and Bacillus thuringiensis.

Multiple locus sequence typing (MLST) was undertaken to extend the genetic characterization of 29 isolates of Bacillus cereus and Bacillus thuringiensis previously characterized in terms of presence/absence of sequences encoding virulence factors and via variable number tandem repeat (VNTR). Additional analysis involved polymerase chain reaction for the presence of sequences (be, cytK, inA, pag, lef, cya and cap), encoding putative virulence factors, not investigated in the earlier study. MLST analysis ascribed novel and unique sequence types to each of the isolates. A phylogenetic tree was constructed from a single sequence of 2,838 bp of concatenated loci sequences. The strains were not monophyletic by analysis of any specific housekeeping gene or virulence characteristic. No clear association in relation to source of isolation or to genotypic profile based on the presence or absence of putative virulence genes could be identified. Comparison of VNTR profiling with MLST data suggested a correlation between these two methods of genetic analysis. In common with the majority of previous studies, MLST was unable to provide clarification of the basis for pathogenicity among members of the B. cereus complex. Nevertheless, our application of MLST served to reinforce the notion that B. cereus and B. thuringiensis should be considered as the same species.

Ultrastructural and pathogenicity of Brevibacillus laterosporus against sinantropic muscoid dipterans.

Brevibacillus laterosporus has entomopathogenic potential against several orders of insects and its wide bioactivity is associated with a variety of strain-specific molecules. In order to avoid the use of synthetic insecticides, along with the need to control insect pests, microbial control has been widely used. Muscoid dipterans are known for their medical-veterinary and sanitary importance, and synanthropy. The enormous biotechnological potential of B. laterosporus has been demonstrated, but there are still few studies with muscoid dipterans. The aim of the study was to verify the mortality of B. laterosporus NRS590 on synanthropic flies and to characterize its different cell stages ultrastructurally. The flies were collected from garbage bins and the colonies were adapted to the laboratory conditions. Bioassays with neo larvae were carried out from the bacterial growth in the phases: vegetative (6 hr), sporangium (20 hr), and free spores (44 hr). An aliquot of each phase was collected for Transmission (TEM) and Scanning Electron Microscopy (SEM). The effectiveness of NRS590 was observed in the sporulation phase, where the corrected mortality was 83.3, 85.1, and 99% for Chrysomya megacephala, Chrysomya putoria, and Musca domestica, respectively. The parasporal body was observed in detail on the entire spore surface. Although our knowledge of this bacterium is growing, it remains to be determined the real virulence factors responsible for the wide entomopathogenic activity observed on muscoid dipterans. Therefore, this study can provide subsidies for the improvement of efficient and safe microbial control techniques for the environment and living beings.

Antimicrobial Activity of Aspergillus sp. from the Amazon Biome: Isolation of Kojic Acid.

The antimicrobial potential of Aspergillus sp., isolated from the Amazon biome, which is stored at the Amazon Fungi Collection-CFAM at ILMD/FIOCRUZ, was evaluated. The fungal culture was cultivated in yeast extract agar and sucrose (YES) for cold extraction of the biocompounds in ethyl acetate at 28 °C for 7 days in a BOD type incubator. The obtained extract was evaluated for its antimicrobial activity against Candida albicans and Gram-positive and negative bacteria by the "cup plate" method and the determination of the minimum inhibitory concentration (MIC) by the broth microdilution method. The extract was subjected to thin layer chromatography (TLC) and fractionated by open and semipreparative column chromatography. The fractions of interest had their chemical constituents elucidated by nuclear magnetic resonance and mass spectrometry. The elucidated molecule was evaluated for cytotoxicity against the human fibroblast strain (MRC5). The extract presented inhibitory activity against both Gram-positive and negative bacteria, with the range of inhibition halos from 5.3 to 14 mm in diameter and an MIC ranging from 500 to 15.6 µg/mL. Seventy-one fractions were collected and TLC analysis suggested the presence of substances with double bond groups: coumarins, flavonoids, phenolic, alkaloids, and terpenes. NMR and MS analyses demonstrated that the isolated molecule was kojic acid. The results of the cytotoxicity test showed that MRC5 cells presented viability at concentrations from 500 to 7.81 µg/mL. The kojic acid molecule of Aspergillus sp., with antibacterial activity and moderate toxicity at the concentrations tested, is a promising prototype of an alternative active principle of an antimicrobial drug.

Surveillance of antimicrobial resistant bacteria in flies (Diptera) in Rio de Janeiro city.

Antimicrobial-resistant bacteria were isolated from muscoid dipterans collected at five different areas of Rio de Janeiro city, in proximity to hospitals. Extracts obtained by maceration of flies were diluted and used as inocula for different culture media, with or without antibiotic (ceftriaxone 1 mg/L) supplementation. Purified isolates were submitted to antimicrobial susceptibility testing (AST). Bacterial identification was performed by MALDI TOF Microflex LT (Bruker Daltonics). A total of 197 bacterial strains were obtained from 117 dipterous muscoids. Forty-two flies (35.9%) carried bacteria resistant to at least one antimicrobial, while 7 insects (5.9%) carried multidrug-resistant bacteria (MDR), which were all members of the family Enterobacteriaceae. Among 10 MDR bacteria (5%), 5 strains (2,5%) were positive by PCR for one or more of the following antibiotic resistance genes: aac(6')-Ib, blaTEM-1, blaCTX-M-15, blaKPC-2 and blaNDM-1. Analysis of variance (ANOVA) and cluster analysis compared the number of resistant isolates per collection point and showed that a single location was statistically different from the others with regard to resistance. Although there are still no criteria to determine the environmental contamination by resistant bacteria the fact that they have been isolated from flies is an indication of a disseminated contamination. As such, these insects may be useful in monitoring programs of antibiotic resistance in non-hospital environments, where they could function as sentinels.

Multidrug-resistant Klebsiella quasipneumoniae subsp. similipneumoniae carrying blaNDM-blaCTX-M15 isolated from flies in Rio de Janeiro, Brazil.

OBJECTIVES: Flies have been implicated in the dispersal of medically important bacteria including members of the genus Klebsiella between different environmental compartments. The aim of this study was to retrieve and characterize antibiotic-resistant bacteria from flies collected near to hospitals. METHODS: Flies were collected in the vicinity of medical facilities and examined for bacteria demonstrating phenotypic resistance to ceftriaxone, followed by determination of phenotypic and genotypic resistance profiles. In addition, whole genome sequencing followed by phylogenetic analysis and resistance genotyping were performed with the multidrug-resistant (MDR) strain Lemef23, identified as Klebsiella quasipneumoniae subsp. similipneumoniae. RESULTS: The strain Lemef23, classified by multiple locus sequence typing as novel ST 3397, harboured numerous resistance genes. The blaNDM was located on a Tn3000 element, a common genetic platform for the carriage of this gene in Brazil. Inference of phylogenetic orthology of strain Lemef23 and other clinical isolates suggested an anthropogenic origin. CONCLUSIONS: The findings of this study support the role of flies as vectors of MDR bacteria of clinical importance and provide the first record of blaNDM-1 and blaCTXM-15 in a Brazilian isolate of K. quasipneumoniae subsp. similipneumoniae, demonstrating the value of surveying insects as reservoirs of antibiotic resistance.

KPC-2 producing Pseudomonas putida as an unexpected pathogen of catheter-associated bloodstream infection.

Infections due to multidrug resistant Gram-negative pathogens are of great concern worldwide, as they are frequently associated with high mortality and morbidity rates. The occurrence of Pseudomonas spp. producing Klebsiella pneumoniae carbapenemases (KPCs) imposes a great challenge through treatment course of bloodstream infections (BSIs). Pseudomonas putida has been recognized as an emerging pathogen of healthcare associated infections (HAIs). Therefore, we aimed to report a case of a non-fatal case of peripheral line associated BSI (PLA-BSI) in an immunocompromised host due to P. putida harboring blaKPC-2 gene in Brazil. A P. putida isolate was recovered from a blood culture of a 72-year-old man admitted at a University Hospital, identified by BD Phoenix™ 100 (Becton, Dickinson and Company), causing PLA-BSI. The species identification was confirmed by Matrix-Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS) and resistance to carbapenems were confirmed by Epsilometer test (E-test®). Additionally, the presence of important carbapenemases genes (blaKPC, blaNDM, blaOXA-48-like, blaSPM, blaIMP, blaVIM) was investigated by Polymerase Chain Reaction. The bacterial isolate was confirmed as meropenem resistant P. putida harboring blaKPC-2 gene.Thereofre, these fidings suggest that P. putida can work as a reservoir for resistance genes as this bacterium has the ability to disseminate through water-fluids inside hospital and community settings. Moreover, this paper highlights that a frequent and worldwide disseminated mechanism of resistance (blaKPC-2) is currently occurring among uncommon agents of BSI.

Larvicidal and adulticidal effects and ultrastructural changes of larvae midgut epithelium of Musca domestica (Diptera: Muscidae) fed with Bacillus thuringiensis var. kyushuensis.

INTRODUCTION: Musca domestica is resistant to many insecticides; hence, biological control is a suitable alternative. METHODS: We evaluated the lethality of strain Btk176 towards the larval and adult M. domestica and the histopathological effects in the larvae midgut. RESULTS: We observed 99% larval and 78.9% adult mortality within 48 hours of spore ingestion (dosage, 2.4×108 CFU/ml). The histopathological effects were consistent with cytotoxicity. PCR analysis showed the presence of the cry1Ba gene. Transmission electron microscopy revealed a bipyramidal parasporal body. Thurigiensin activity was not detected. CONCLUSIONS: The serovar, Btk176 might be a potential biocontrol agent for houseflies.

Application of 16S rDNA-DGGE and plate culture to characterization of bacterial communities associated with the sawfly, Acantholyda erythrocephala (Hymenoptera, Pamphiliidae).

Culture-based analysis was employed in parallel with PCR amplification of 16S rDNA, coupled with denaturing gradient gel electrophoresis (DGGE), to profile bacterial species associated with different developmental stages of the pine false webworm (PFW), Acantholyda erythrocephala, a sawfly pest responsible for incidents of severe defoliation in commercially important tree plantations in North America. Culture-based analysis revealed that Pseudomonas spp. along with Bacillus sphaericus and Arthrobacter sp. were the predominant components of the microflora of the internal organs and identified life-stage-specific associations including Photorhabdus temperata with egg and larval samples and a Janthinobacterium sp. with eonymphs. PCR-DGGE confirmed the predominance of Pseudomonas spp. and B. sphaericus in the majority of samples but did not detect Arthrobacter sp., P. temperate, or Janthinobacterium sp. In contrast, DGGE revealed the presence of a Chryseobacterium sp. as the predominant component of the PFW micoflora at all life stages, with the exception of adults. This species had been infrequently cultured, at low levels, from a limited number of samples and the existence of a possible relationship between this bacterium and the PFW had gone unnoticed using the culture-based approach. Our findings highlight the advantages of applying a dual approach to the study of microbe-insect associations and demonstrate that the benefits of one system can be used to overcome some of the limitations of the other.

Preliminary screening of the larvicidal effect of Brevibacillus laterosporus strains against the blowfly Chrysomya megacephala (Fabricius, 1794) (Diptera: Calliphoridae).

INTRODUCTION: This study evaluated whether different strains of Brevibacillus laterosporus could be used to control larvae of the blowfly Chrysomya megacephala, a pest that affects both human and animal health. METHODS: Mortality rates were recorded after 1-mL suspensions of sporulated cells of 14 different strains of B. laterosporus were added to 2.5g of premixed diet consisting of rotting ground beef fed to first instar larvae of C. megacephala. All bioassays were performed using 10 larvae per strain, with a minimum of three replicates for each bioassay. Larval mortality was recorded daily up to seven days. RESULTS: Strains Bon 707, IGM 16-92, and Shi 3 showed the highest toxicity toward the larvae producing 70.5%, 64.5%, and 51.6% of larval mortality, respectively, which was significantly higher than that in the control group (p < 0.05). In contrast, strains NRS 1642, NRS 661, NRS 590 BL 856, NRS 342, ATCC 6457, Bon 712, and NRS 1247 showed limited or no pathogenic activity against the target larvae. CONCLUSIONS: Our preliminary data indicated that B. laterosporus could be used to develop bioinsecticides against C. megacephala.

Characterization of nitrogen-fixing Paenibacillus species by polymerase chain reaction-restriction fragment length polymorphism analysis of part of genes encoding 16S rRNA and 23S rRNA and by multilocus enzyme electrophoresis.

Forty-two strains representing the eight recognized nitrogen-fixing Paenibacillus species and 12 non-identified strains were examined by restriction fragment length polymorphism (RFLP) analysis of part of 16S and 23S rRNA genes amplified by polymerase chain reaction (PCR). Eleven different 16S rDNA genotypes were obtained from the combined data of RFLP analysis with four endonucleases and they were in agreement with the established taxonomic classification. Only one group of unclassified strains (Group I) was assigned in a separate genotype, suggesting they belong to a new species. Using the 23S PCR-RFLP method only six genotypes were detected, showing that this method is less discriminative than the 16S PCR-RFLP. Using the multilocus enzyme electrophoresis (MLEE) assay, the 48 strains tested could be classified into 35 zymovars. The seven enzymatic loci tested were polymorphic and the different profiles obtained among strains allowed the grouping of strains into 10 clusters. The PCR-RFLP methods together with the MLEE assay provide a rapid tool for the characterization and the establishment of the taxonomic position of isolates belonging to this nitrogen-fixing group, which shows a great potentiality in promoting plant growth.

Genotypic and phenotypic characterization of enterotoxigenic Escherichia coli (ETEC) strains isolated in Rio de Janeiro city, Brazil.

Enterotoxigenic Escherichia coli (ETEC) strains have been implicated as important etiological agents of diarrheal disease, especially in developing countries. This group of microorganisms has been associated with a diverse range of genotypic and phenotypic markers. In the present study, 21 ETEC isolates previously defined according to the toxigenic genotypes, were characterized on the basis of O:H typing, cell adherence patterns, and colonization factors (CFs) antigens. Genetic diversity was investigated by random amplification polymorphic DNA (RAPD-PCR), pulsed-field gel electrophoresis (PFGE) and multilocus enzyme electrophoresis (MLEE). LT-I probe-positive isolates belonged to serotypes ONT:HNT, O7:H24, O48:H21, O88:H25, O148:H28, O159:H17 and O159:H21. ST-h probe-positive isolates belonged to serotypes O159:H17, O148:H28 and O6:H-. Serotypes O148:H28, O159:H17 and O6:H- were associated with the CS6, CFA/I and CS1 CS3 antigens, respectively. Most ETEC strains exhibited a diffuse pattern of adherence to cultured epithelial cells. In general, phenotypic and genotypic characteristics correlated well. RAPD-PCR, PFGE and MLEE showed reproducibility and good discriminatory potential. The application of molecular typing systems allowed the detection of significant diversity among the isolates, indicating a non-clonal origin and revealing intra-serotype variation overlooked by classical epidemiological approaches. The phenotypic and genotypic diversity observed lead us to recommend the use of different typing systems in order to elucidate the epidemiology of ETEC infection.