Enterobacterial Repetitive Intergenic Consensus-polymerase Chain Research Articles

Multidrug resistance genes, including blaKPC and blaCTX-M-2, among Klebsiella pneumoniae isolated in Recife, Brazil

The prevalence of cephalosporins and carbapenem-resistant Klebsiella pneumoniae strains is rising in Brazil, with potential serious consequences in terms of patients' outcomes and general care. This study characterized 24 clinical isolates of K. pneumoniae from two hospitals in Recife, Brazil, through the antimicrobial susceptibility profile, analyses of β-lactamase genes (bla(TEM), bla(SHV),bla(CTX-M), bla(KPC), bla(VIM), bla(IMP), and bla(SPM), plasmidial profile and ERIC-PCR (Enterobacterial repetitive intergenic consensus-polymerase chain reaction). ERIC-PCR and plasmidial analysis grouped the isolates in 17 and 19 patterns, respectively. Six isolates from one hospital presented the same pattern by ERIC-PCR, indicating clonal dissemination. All isolates presented bla(SHV), 62.5% presented bla(CTX)-M-2, 29% bla(TEM), and 41.7% bla(KPC). Metallo-β-lactamase genes bla(VIM), bla(IMP), and bla(SPM) not detected. Eleven isolates were identified carrying at least 3 β-lactamase studied genes, and 2 isolates carried bla(SHV), bla(TEM), bla (CTX-M-2) and bla(KPC) simultaneously. The accumulation of resistance genes in some strains, observed in this study, imposes limitations in the therapeutic options available for the treatment of infections caused by K. pneumoniae in Recife, Brazil. These results should alert the Brazilian medical authorities to establish rigorous methods for more efficiently control the dissemination of antimicrobial resistance genes in the hospital environment.

Four cases of possible human infections with Delftia lacustris

We report four cases of possible human infections with Delftia lacustris. D. lacustris isolates, which were isolated from blood cultures and bile fluid of patients with underlying diseases such as empyema, renal injury, hepatocellular carcinoma, and renal infarction, were identified using 16S rRNA gene sequencing and biochemical tests. Four D. lacustris isolates did not show the same antimicrobial susceptibility profiles and enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) patterns, indicating their non-clonality.

Phylogenetic Diversity ofAeromonasfrom “Alheira,” a Traditional Portuguese Meat Product

"Alheira" is a traditional smoked meat sausage produced in the north of Portugal, representing an important economic resource for the region. This meat product has been subjected to research studies with the aim of detecting the presence of common foodborne pathogens, but, to our knowledge, isolation of emerging foodborne Aeromonas from alheira has never been previously described. Present work attempts to evaluate the Aeromonas species diversity of 84 isolates of Aeromonas spp. collected from 32 alheira samples. All presumptive Aeromonas isolates were subjected to genotyping by enterobacterial repetitive intergenic consensus-polymerase chain reaction analysis. The isolates presenting a different pattern were subjected to gyrB gene sequencing for species classification, and the species A. hydrophila, A. salmonicida, A. caviae, A. media, and A. allosaccharophila were identified. The Aeromonas species diversity found has not been previously described in any other meat product evaluated in previous studies. It is also important to highlight the presence of A. hydrophila and A. caviae because they were previously associated with illness in humans, including gastroenteritis.

Exposure to clinical X-ray radiation does not alter antibiotic susceptibility or genotype profile in Gram-negative and Gram-positive clinical pathogens

ABSTRACTInadvertent exposure of bacterial pathogens to X-ray radiation may be an environmental stress, where the bacterium may respond by increasing mutational events, thereby potentially resulting in increased antibiotic resistance and alteration to genotypic profile. In order to examine this, four clinical pathogens, including the Gram-negative organisms Escherichia coli O157:H7 NCTC12900 and Pseudomonas aeruginosa NCTC10662, as well as the Grampositive organisms Staphylococcus aureus NCTC6571 and Enterococcus faecium were exposed to X-rays (35,495 cGy/cm2) over a seven-day period. Antibiotic susceptibility was assessed before, during and after exposure by examining susceptibility, as quantified by E-test with six antibiotics, as well as to a further 11 antibiotics by measurement of susceptibility zone sizes (mm). Additionally, the DNA profile of each organism was compared before, during and after exposure employing the enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC PCR). Results indicated that exposure of these organisms to this amount of X-ray radiation did not alter their antibiotic susceptibility, nor their genomic DNA profile. Overall, these data indicate that exposure of bacteria to X-ray radiation does not alter the test organisms' antibiotic susceptibility profiles, nor alter genomic DNA profiles of bacteria, which therefore does not compromise molecular epidemiological tracking of bacteria within healthcare environments in which patients have been exposed to X-ray radiation.

Grass carp (Ctenopharyngodon idellus) infected with multiple strains of Aeromonas hydrophila

Ctenopharyngodon idellus is an important commercial fish species in China and many other countries to meet human food habits. However, there is no definitive data to indicate the multi-infection of pathogenic Aeromonas hydrophila strains in cultured C. idellus. In this study, four strong virulent strains with five virulence genes were simultaneously isolated from the cultured C. idellus suffering from septicemia, and identified as different A. hydrophila isolates using the ATB 32GN system, phylogenetic analysis, enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR). They were susceptible to chloramphenicol, tobramycin, kanamycin, norfloxacin, spectinomycin, furantoin, azithromycin, and resistant to carbenicillin, penbritin, clindamycin. In addition, to further control the multi-infection of A. hydrophila, norfloxacin, the well-known fishery drug widespread used in aquaculture, was employed to treat this disease. Its minimum inhibitory concentrations (MICs) were 2~4 mg/L and good protection effects were also exhibited on the naturally infected fish at a final concentration of 1 and 2 g/kg in the feed (cal. 20 and 40 mg/kg of fish). As an important pathogen of a zoonotic and foodborne disease, the multi-infection of A. hydrophila strains may be an emerging threat in grass carp farming and food safety, and more importance should be attached to their multi-infection in fish farming. Key words: Ctenopharyngodon idellus, Aeromonas hydrophila, multi-infection, control.

Changes in Concentrations of Fluoroquinolones and of Ciprofloxacin-resistant Enterobacteriaceae in Chicken Feces and Manure Stored in a Heap

This study evaluated the impact of storing chicken manure on the degradation of enrofloxacin (ENR) and ciprofloxacin (CIP), and on the survival of CIP-resistant Enterobacteriaceae. At 24 d of age, half of 8900 chickens received ENR for 5 d. After the animals departed, their manure was stored in two heaps for 63 d. Enterobacteriaceae were cultured on media containing 0 to 32 mg L⁻¹ of CIP. A total of 320 isolates were fingerprinted using enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) to evaluate community structure. Initial concentrations of ENR and CIP in the heap were 22 and 1.8 mg kg⁻¹, respectively. Seventy-three percent of the two fluoroquinolones were eliminated during storage. The administration of ENR led to a 5.1 log₋₁₀ decrease in Enterobacteriaceae concentrations and emergence of CIP-resistant bacteria, which became dominant in the feces. concentrations decreased 1.2 to 2.3 log₋₁₀ 2 d after the heaps were made and continued to decline during storage. No resistant were found by Day 63. The highest CIP minimum inhibitory concentration (MIC) values observed among isolates of and of both and sp. were 128 and 4 mg L⁻¹, respectively. The dominant ERIC-PCR profiles changed over time. There was no relationship between genotype and resistance-isolated strains to CIP. Storing chicken manure in heaps appeared to be an effective way of limiting the entrance of CIP-resistant E. coli into the environment but did not prevent the dissemination of fluoroquinolones after land spreading.

Bacterial diversity of lipase-producing strains in different soils in southwest of China and characteristics of lipase

Due to the rapid development observed in industries, environmental pollution became more and more critical. Lipase-producing strains played a key role in the enzymological remediation of polluted soils. Diversity of culturable lipase-producing bacteria in the southwest of China was studied with 198 samples collected from different points, along the transect from Tibetan Plateau-Ya An–Sichuan Basin. The enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) technology was used to amplify the isolated lipolytic producer’s DNA samples and the amplified results were analyzed by NTSYS-pc2.1 to identify the similarity of isolates. A total of 54 bacterial strains were isolated from samples: 21 strains from Sichuan Basin (38.9%), 15 strains from Ya An (27.8%) and 18 strains from Tibetan Plateau (33.3%). The result of enzyme activity analysis showed that intracellular enzyme activity was nearly three folds than extracellular enzyme activity, and the intracellular enzyme activity was 6.79, 6.23 and 5.59 U/ml from Sichuan Basin, Ya An and Tibetan Plateau, respectively. Based on 16S rRNA gene sequence analysis, 12 strains were identified and belonged to Bacillus, Klebsiella, Pseudomonas and Enterobacter. The results showed that the Bacillus strains were the preponderant strains in the Tibetan Plateau and the Klebsiella strains were predominant isolates in Ya An. It suggested that the strains of Klebsiella were the transitional lipase-producing strains from Tibetan Plateau to Sichuan Basin. It could be concluded that the diversity of lipase-producing strains showed a transitional tendency: diversity of lipase-producing strains in Sichuan Basin were significantly higher than that of other two places and the diversity decreased gradually from plain region to Plateau region. Key words: Enterobacterial repetitive intergenic consensus-polymerase chain reaction(ERIC-PCR), lipase-producing microorganisms, diversity, Tibetan Plateau

Bacterial community in the roots and rhizosphere of Hypericum silenoides Juss. 1804

Hypericum silenoides Juss. 1804 is an important medicinal plant used in Mexico, but the bacterial community associated with it is unknown. The bacterial communities in the rhizosphere and roots of H. silenoides were isolated and identified by enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) and ribosomal types were determined by amplified ribosomal rDNA restriction analysis (ARDRA) and 16S rRNA gene sequences. Sixty-six strains were obtained from roots of H. silenoides and 37 were isolated from the rhizosphere. ERIC fingerprinting distinguished 63 genetic patterns with 44 being unique and the remaining 19 containing 59 strains. Eighteen representative strains were distinguished with ARDRA analysis. 16S rRNA gene sequence analysis revealed that the bacteria isolated from the roots and rhizosphere of H. silenoides belonged to the genera Acinetobacter, Enterobacter, Pseudomonas, Sphingobium, Stenotrophomonas, Agrobacterium, Pantoea and Serratia. The largest number of isolates (30) belonged to the genus Agrobacterium. Richness and diversity of bacteria was higher on the roots than in the rhizosphere of H. silenoides.

Molecular characterization of Antarctic actinobacteria and screening for antimicrobial metabolite production

The present study aimed to isolate actinobacteria from soil samples and characterized them using molecular tools and screened their secondary metabolites for antimicrobial activities. Thirty-nine strains from four different location of Barrientos Island, Antarctica using 12 types of isolation media was isolated. The isolates were preceded to screening of secondary metabolites for antimicrobial and antifungal activities. Using high-throughput screening methods, 38% (15/39) of isolates produced bioactive metabolites. Approximately 18% (7/39), 18% (7/39), 10% (4/39) and 2.5% (1/39) of isolates inhibited growth of Candida albicans ATCC 10231(T), Staphylococcus aurues ATCC 51650(T), methicillin-resistant Staphylococcus aurues (MRSA) ATCC BAA-44(T) and Pseudomonas aeruginosa ATCC 10145(T), respectively. Molecular characterization techniques like 16S rRNA analysis, Enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR), Random amplified polymorphic DNA (RAPD) and composite analyses were used to characterize the actinobacteria strains. Analysis of 16S rRNA sequences is still one of the most powerful methods to determine higher taxonomic relationships of Actinobacteria. Both RAPD and ERIC-PCR fingerprinting have shown good discriminatory capability but RAPD proved to be better in discriminatory power than ERIC-PCR. Our results demonstrated that composite analysis of both fingerprinting generally increased the discrimination ability and generated best clustering for actinobacteria strains in this study.

Genetic Diversity of a Brazilian Strain Collection of Xanthomonas citri subsp. citri Based on the Type III Effector Protein Genes.

Exclusion and eradication or management based on an integrated approach with less susceptible varieties, copper-based bactericides, and windbreaks are the two main strategies used to prevent or control citrus canker. Field tolerance or resistance to citrus canker is not found in the most important commercial sweet orange cultivars, and pathogen-derived resistance has been developed and applied in different crops to obtain resistant genotypes to plant pathogens. We describe the development of DNA primers and probes based on the type III effector genes avrXacE1, avrXacE2, avrXacE3, avrBs2, pthA4, hpaF, and XAC3090 (leucine rich protein), and their application in the evaluation of the genetic diversity of the pathogen. A total of 49 haplotypes were identified in 157 strains by Southern blot analysis. No genetic polymorphism was detected by BOX elements - and enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) analysis, nor with the genes avrBs2, XAC3090, and hpaF. Nei's genetic diversity indexes varied from 0.65 to 0.96 for subcollections of the pathogen. One or few haplotypes were most frequent in the strain collection, but several haplotypes were represented by solely one or few strains. The PthA4 probe resulted in the higher number of haplotypes identified in the Brazilian subcollections. Greater variation in the frequency of haplotypes occurred within subcollections (93.7%) than among subcollections. Only some haplotypes were genetically distant from all others, especially those originated from Rio Grande do Sul and Santa Catarina states. These bacterial effectors are widely spread in the collections and are useful for a better understanding of the host-pathogen interaction and the search for resistance genes in host and nonhost plants.

Molecular characterization of clinical multiresistant isolates of Acinetobacter sp. from hospitals in Porto Alegre, State of Rio Grande do Sul, Brazil

Hospitals around the world have presented multiresistant Acinetobacter sp. outbreaks. The spread of these isolates that harbor an increasing variety of resistance genes makes the treatment of these infections and their control within the hospital environment more difficult. This study aimed to evaluate the occurrence and dissemination of Acinetobacter sp. multiresistant isolates and to identify acquired resistance genes. We analyzed 274 clinical isolates of Acinetobacter sp. from five hospitals in Porto Alegre, RS, Brazil. We evaluated the susceptibility to antimicrobial, acquired resistance genes from Ambler's classes B and D, and performed molecular typing of the isolates using enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) technique. A high (68%) percentage of multiresistant isolates of Acinetobacter sp. was observed, and 69% were resistant to carbapenems. We identified 84% of isolates belonging to species A. baumannii because they presented the gene blaOXA-51. The gene blaOXA-23 was detected in 62% of the isolates, and among these, 98% were resistant to carbapenems. Using the ERIC-PCR technique, we identified clones of Acinetobacter sp. spread among the four hospitals analyzed during the sampling period. The data indicate the dissemination of Acinetobacter sp. isolates among hospitals and their permanence in the hospital after one year.

The Characterization and Comparison ofStaphylococcus aureusby Antibiotic Susceptibility Testing, Enterobacterial Repetitive Intergenic Consensus–Polymerase Chain Reaction, and Random Amplified Polymorphic DNA–Polymerase Chain Reaction

Thirty-five of Staphylococcus aureus isolated from food raw materials and workers' hands in a noshery were characterized using antibiotic susceptibility testing, enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR), and random amplified polymorphic DNA (RAPD)-PCR. As a similarity threshold of 90%, ERIC-PCR classified 35 S. aureus isolates into 28 ERIC types with discrimination indexes (D) of 0.984, while RAPD-PCR grouped 35 S. aureus isolates into five clusters (A-E) showing 19 RAPD types with D of 0.949. Four resistance patterns were observed with D of 0.826. A comparison of characterization of S. aureus indicated a clear correlation between ERIC-PCR and RAPD-PCR or resistance patterns in some strains. It was concluded that ERIC-PCR method could be used for genetic diversity of S. aureus and tracing the sources of it from the food chain.

Molecular cloning, sequencing, and expression of the outer membrane protein P2 gene of Haemophilus parasuis

Haemophilus parasuis is the etiological agent of Glässer’s disease characterized by fibrinous polyserositis, polyarthritis, and meningitis in young pigs. But it is difficult to develop universal serological diagnostic tools and effective vaccines against this disease because of the serovar diversity of the isolates. In this study, enterobacterial repetitive intergenic consensus-polymerase chain reaction, were performed to investigate the gene profile of 111 isolates of H. parasuis from China. And a specific common gene of H. parasuis was cloned and identified as the outer-membrane protein (OMP) P2 gene. Sequencing results of OMP P2 genes of 22 isolates showed that they had high homology and could be divided into 2 genetic types. Moreover, the OMPP2 protein was expressed in Escherichia coli expressing system. And the purified recombinant protein provided partial protection against H. parasuis infection in mice. It suggested the OMP P2 was an immunogenic protein and had great potential to serve as a vaccine and diagnostic antigen.

Enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) fingerprinting reveals intra-serotype variations among circulating Listeria monocytogenes strains

Forty-five presumptive Listeria monocytogenes isolates were confirmed by multiplexpolymerase chain reaction (PCR) and characterized for antimicrobial susceptibility and tolerance to commonly used disinfectants. Isolates were also serotyped by PCR and characterized by enterobacterial repetitive intergenic consensus ERIC-PCR fingerprinting. All of the isolates showed PCR products of 938 bp (genus) and of 750 bp (species). Antimicrobial susceptibility was 100% for ampicillin, amoxicillin/ clavulanic acid, vancomycin and chloramphenicol, whereas for trimethoprim/ sulfamethoxazole it was 98, azithromycin 96, erythromycin 91, tetracycline 82, penicillin 97.8 (2.2% no susceptible), ciprofloxacin 84.4, rifampin 64.4, meropenem 71.1 and clindamycin 22.2%, respectively. All the isolates were resistant to cephalosporins. 71% of the isolates showed a MIC ≤ 200 ppm/10 to15 min for sodium hypochlorite and 98% a MIC ≤ 1.5%/2 to15 min for Tego-51. 58% of isolates were serotyped as 4b/4d/4e, 16% as ½b/3b, 7% as ½a/3a, and 4% as ½c/3c. ERIC-PCR showed 28 polymorphic bands ranging from 100 to 2810 bp that did not cluster according to any phenotype. ERIC-PCR fingerprinting revealed intra-serotypic variations and proved that different L. monocytogenes strains were circulating in the country during the isolation period. Key words: Listeria monocytogenes, molecular serotyping, antimicrobial susceptibility, disinfectant tolerance, enterobacterial repetitive intergenic consensus- polymerase chain reaction (ERIC-PCR).

Prevalence of Listeria monocytogenes in raw meats marketed in Bangkok and characterization of the isolates by phenotypic and molecular methods.

Listeria monocytogenes causes listeriosis characterized by septicaemia, encephalitis, and abortion or stillbirth. Regular monitoring of its prevalence in food and characterization of its phenotypes and genotypes are necessary for disease surveillance and tracing the epidemic outbreaks. In this study, the prevalence of L. monocytogenes in raw meats marketed in Bangkok was 15.4%. The bacteria isolated from meat were serotyped and genotyped using enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR). Their virulence-associated genes, antimicrobial susceptibility, and ability to invade intestinal epithelial cells were studied. All 22 L. monocytogenes strains isolated from 104 raw meat samples carried virulence-associated genes, such as actA, flaA, hlyA, lap, inlA, inlB, and prfA. These were serotype 4b, suggesting their pathogenic and epidemic potential. These isolates could be classified into six ERIC-PCR groups: A-E The majority (59.1%) of the isolates belonged to Group A, and three isolates were Group D which was closely related to the Group A. Two isolates each were Group C and E, and one isolate each was group B and F. Although the isolates belonged to the same serotype and genotype and were all equipped with the virulence-associated genes, they showed a different cell invasion capability and antibiotic susceptibility. All the isolates were susceptible to ampicillin, amikacin, chloramphenicol, gentamicin, imipenem, penicillin G, sulphamethoxazole-trimethoprim, and tetracycline. However, one isolate showed only intermediate susceptibility to tetracycline. The data provide the first molecular insight into the L. monocytogenes isolates in Thailand and elucidate a potential risk of people contracting listeriosis.

Isolation of Salmonella from Meat Samples and Characterization by Enterobacterial Repetitive Intergenic Consensus–Polymerase Chain Reaction and Antibiotics Test

Salmonella is one of the most important foodborne pathogens associated with severe diseases in animals and humans. Meat samples are considered as one of the main sources of Salmonella infections. Consequently, the survey of Salmonella contamination in meat samples is of outmost importance for the control and prevention of severe diseases. In this study, 250 meat samples were selected for surveys of Salmonella contaminations. Results indicated that 12% (n=30) of samples tested were positive to Salmonella. The genetic characterization of 30 Salmonella was studied by enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR), and 22 of ERIC-PCR types were found with D of 94.8%. In addition, the resistant characterization was also carried out using nine antibiotics test, and nine resistant patterns were observed with D of 88.7%. A good correlation was also observed between ERIC-PCR fingerprinting and resistant patterns in some Salmonella such as SAL 6 and SAL 7.

Polyclonal endemicity of Pseudomonas aeruginosa in a teaching hospital from Brazil: molecular typing of decade-old strains

Pseudomonas aeruginosa infections cause significant mortality and morbidity in health care settings. Strategies to prevent and control the emergence and spread of P. aeruginosa within hospitals involve implementation of barrier methods and antimicrobial stewardship programs. However, there is still much debate over which of these measures holds the utmost importance. Molecular strain typing may help elucidate this issue. In our study, 71 nosocomial isolates from 41 patients and 23 community-acquired isolates from 21 patients were genotyped. Enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) was performed. Band patterns were compared using similarity coefficients of Dice, Jaccard and simple matching. Strain similarity for nosocomial strains varied from 0.14 to 1.00 (Dice); 0.08 to 1.00 (Jaccard) and 0.58 to 1.00 (simple matching). Forty patterns were identified. In most units, several clones coexisted. However, there was evidence of clonal dissemination in the high risk nursery, neurology and two surgical units. Each and every community-acquired strain produced a unique distinct pattern. Results suggest that cross transmission of P. aeruginosa was an uncommon event in our hospital. This points out to a minor role for barrier methods in the control of P. aeruginosa spread.

ERIC-PCR identification of the spread of airborne Escherichia coli in pig houses

To understand the spread of microbial aerosols in pig houses, with Escherichia coli ( E. coli) as indicator, the airborne E. coli in 4 pig houses and their surroundings at different points 10, 50 m upwind and 10, 50, 100, 200 and 400 m downwind respectively from the pig houses were collected, and the concentrations were calculated at each sampling point. Furthermore, the feces of pigs were collected to separate E. coli. The ERIC-PCR (Enterobacterial Repetitive Intergenic Consensus-Polymerase Chain Reaction) technology was used to amplify the isolated E. coli DNA samples, then the amplified results were analyzed by NTSYS-pc (Version 2.10) to identify the similarity of isolated E. coli. The results showed that the airborne E. coli concentrations in indoor air of the 4 pig houses (21–35 CFU m − 3 air) were much higher than those in upwind and downwind air ( P < 0.05), but there were no significant differences ( P > 0.05) at downwind distances. The ERIC-PCR results also showed that 52.4% of the fecal E. coli (four houses being respectively 2/4, 50%; 2/4, 50%; 3/6, 50%; 4/7, 57.1%) were identical to the indoor airborne E. coli isolates, and there was more than 90% similarity between the majority of E. coli (50%, 21/42) isolated from downwind air at 10, 50, 100 and 200 m and those from indoor air or feces. It could be concluded that the aerosols in pig houses can spread to the surroundings, and thus effective measures should be taken to control and minimize the spread of microbial aerosols.

Molecular analyses of Salmonella serotype Typhi and Salmonella serotype Paratyphi B strains isolated in Turkey

To investigate the characteristics of Salmonella serotype Typhi and Salmonella serotype Paratyphi B, which still remain significant in Turkey. Materials and methods: Eighteen S. Typhi and 42 S. Paratyphi B strains isolated from clinical samples were investigated by plasmid profile analysis, enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR), and pulsed field gel electrophoresis (PFGE) methods. Results: Plasmid profile analysis showed that 10 out of 18 (56%) S. Typhi isolates harbored 1 to 3 plasmids, and 11 out of 42 (26.2%) S. Paratyphi B isolates harbored 1 to 4 plasmids. PFGE performed with restriction enzyme AvrII grouped both S. Typhi and S. Paratyphi B isolates into 14 clusters; with restriction enzyme XbaI, S. Typhi and S. Paratyphi B isolates were grouped into 13 and 12 clusters, respectively. Conclusion: These results showed that plasmid profile analysis and PFGE are reliable and discriminative methods complementing the phenotypic characters of S. Typhi and S. Paratyphi B isolates, and may contribute to the epidemiologic investigation of typhoid or paratyphoid diseases. The study presented here is the first report on S. Typhi and S. Paratyphi B isolates from Turkey investigated by plasmid profile analysis, ERIC-PCR, and PFGE methods.

Molecular Investigation of &lt;i&gt;Salmonella&lt;/i&gt; Choleraesuis and &lt;i&gt;Salmonella&lt;/i&gt; Hadar Strains Isolated from Humans in Turkey

Eleven Salmonella Choleraesuis and seven Salmonella Hadar strains isolated from various clinical humand samples were investigated by plasmid profile analysis, enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) and pulsed-field gel electrophoresis (PFGE) in order to obtain information at a molecular level on the epidemiology of S. Choleraesuis and S. Hadar, which are significantly present in Turkey. Plasmid profile analysis showed that 10 (90.9%) of 11 S. Choleraesuis isolates harbored one to two plasmids with sizes of 2.0, 5.0 or 6.5 kb; and 5 (71.4%) of 7 S. Hadar isolates harbored one to three plasmids ranging from 2.5 to 70 kb. ERIC-PCR was performed using ERIC-2 primers; since isolates within each serotype showed similar band models, we concluded that ERIC-PCR is not suitable for differentiating isolates within the same serotype and for grouping into clusters. In PFGE using the AvrII enzyme, S. Choleraesuis isolates formed three clusters, and S. Hadar isolates formed three clusters; using the XbaI enzyme, S. Choleraesuis isolates formed two clusters, and S. Hadar isolates formed four clusters. These results showed that plasmid profile analysis and PFGE are reliable and discriminative methods that would complement antibiograms, and could contribute to the investigation of outbreak epidemiology. This is the first report on S. Choleraesuis and S. Hadar isolates from Turkey investigated by plasmid profile analysis, ERIC-PCR and PFGE methods.