Effectiveness of radiation processing in elimination of Aeromonas from food

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Nagar, Vandan; Bandekar, Jayant R.

2011-08-01

Genus Aeromonas has emerged as an important human pathogen because it causes a variety of diseases including gastroenteritis and extra-intestinal infections. Contaminated water, sprouts, vegetables, seafood and food of animal origin have been considered to be the important sources of Aeromonas infection. In the present study, radiation sensitivity of indigenous strains of Aeromonas spp. from different food samples was evaluated. The decimal reduction dose (D10) values of different Aeromonas isolates in saline at 0-4 °C were in the range of 0.031-0.046 kGy. The mixed sprouts, chicken and fish samples were inoculated with a cocktail of five most resistant isolates (A. salmonicida Y567, A. caviae A85, A. jandaei A514A, A. hydrophila CECT 839T and A. veronii Y47) and exposed to γ radiation to study the effectiveness of radiation treatment in elimination of Aeromonas. D10 values of Aeromonas cocktail in mixed sprouts, chicken and fish samples were found to be 0.081±0.001, 0.089±0.003 and 0.091±0.003 kGy, respectively. Radiation treatment with a 1.5 kGy dose resulted in complete elimination of 105 CFU/g of Aeromonas spp. from mixed sprouts, chicken and fish samples. No recovery of Aeromonas was observed in the 1.5 kGy treated samples stored at 4 °C up to 12 (mixed sprouts) and 7 days (chicken and fish samples), even after enrichment and selective plating. This study demonstrates that a 1.5 kGy dose of irradiation treatment could result in complete elimination of 105 CFU/g of Aeromonas spp. from mixed sprouts, chicken and fish samples.

Effectiveness of radiation processing in elimination of Aeromonas from food

International Nuclear Information System (INIS)

Nagar, Vandan; Bandekar, Jayant R.

2011-01-01

Genus Aeromonas has emerged as an important human pathogen because it causes a variety of diseases including gastroenteritis and extra-intestinal infections. Contaminated water, sprouts, vegetables, seafood and food of animal origin have been considered to be the important sources of Aeromonas infection. In the present study, radiation sensitivity of indigenous strains of Aeromonas spp. from different food samples was evaluated. The decimal reduction dose (D 10 ) values of different Aeromonas isolates in saline at 0-4 o C were in the range of 0.031-0.046 kGy. The mixed sprouts, chicken and fish samples were inoculated with a cocktail of five most resistant isolates (A. salmonicida Y567, A. caviae A85, A. jandaei A514A, A. hydrophila CECT 839 T and A. veronii Y47) and exposed to γ radiation to study the effectiveness of radiation treatment in elimination of Aeromonas. D 10 values of Aeromonas cocktail in mixed sprouts, chicken and fish samples were found to be 0.081±0.001, 0.089±0.003 and 0.091±0.003 kGy, respectively. Radiation treatment with a 1.5 kGy dose resulted in complete elimination of 10 5 CFU/g of Aeromonas spp. from mixed sprouts, chicken and fish samples. No recovery of Aeromonas was observed in the 1.5 kGy treated samples stored at 4 o C up to 12 (mixed sprouts) and 7 days (chicken and fish samples), even after enrichment and selective plating. This study demonstrates that a 1.5 kGy dose of irradiation treatment could result in complete elimination of 10 5 CFU/g of Aeromonas spp. from mixed sprouts, chicken and fish samples.

Effectiveness of radiation processing in elimination of Aeromonas from food

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Nagar, Vandan [Food Technology Division, Bhabha Atomic Research Centre, Mumbai 400085 (India); Bandekar, Jayant R., E-mail: jrb@barc.gov.i [Food Technology Division, Bhabha Atomic Research Centre, Mumbai 400085 (India)

2011-08-15

Genus Aeromonas has emerged as an important human pathogen because it causes a variety of diseases including gastroenteritis and extra-intestinal infections. Contaminated water, sprouts, vegetables, seafood and food of animal origin have been considered to be the important sources of Aeromonas infection. In the present study, radiation sensitivity of indigenous strains of Aeromonas spp. from different food samples was evaluated. The decimal reduction dose (D{sub 10}) values of different Aeromonas isolates in saline at 0-4 {sup o}C were in the range of 0.031-0.046 kGy. The mixed sprouts, chicken and fish samples were inoculated with a cocktail of five most resistant isolates (A. salmonicida Y567, A. caviae A85, A. jandaei A514A, A. hydrophila CECT 839{sup T} and A. veronii Y47) and exposed to {gamma} radiation to study the effectiveness of radiation treatment in elimination of Aeromonas. D{sub 10} values of Aeromonas cocktail in mixed sprouts, chicken and fish samples were found to be 0.081{+-}0.001, 0.089{+-}0.003 and 0.091{+-}0.003 kGy, respectively. Radiation treatment with a 1.5 kGy dose resulted in complete elimination of 10{sup 5} CFU/g of Aeromonas spp. from mixed sprouts, chicken and fish samples. No recovery of Aeromonas was observed in the 1.5 kGy treated samples stored at 4 {sup o}C up to 12 (mixed sprouts) and 7 days (chicken and fish samples), even after enrichment and selective plating. This study demonstrates that a 1.5 kGy dose of irradiation treatment could result in complete elimination of 10{sup 5} CFU/g of Aeromonas spp. from mixed sprouts, chicken and fish samples.

Characterization of class 1 integrons associated with R-plasmids in clinical Aeromonas salmonicida isolates from various geographical areas

DEFF Research Database (Denmark)

Schmidt, A.S.; Bruun, Morten Sichlau; Larsen, J.L.

2001-01-01

Class 1 integrons were found in 26 of 40 antibiotic-resistant isolates of the fish pathogen Aeromonas salmonicida from Northern Europe and North America. Three different dhfr genes, conferring trimethoprim resistance, and one ant(3 " )1a aminoglycoside resistance gene were identified as gene...... inserts. The gene cassettes tended to be conserved among isolates from a particular geographical area. Nineteen isolates transferred R- plasmids carrying different tet determinants to Escherichia coli in filter mating assays, and in 15 cases, the class 1 integrons were co-transferred. Transferable...... sulphadiazine, trimethoprim and streptomycin resistances were invariably encoded by integrons. It thus appears that integron-encoded antibiotic resistance genes contribute substantially to the horizontal spread of antimicrobial resistance within this species, being associated with conjugative plasmids....

Susceptibilities to carbapenems and presence of cphA gene on food-borne Aeromonas

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Bibiana María Martín Talavera

2006-07-01

Full Text Available The purpose of this study was to determine the susceptibilities of food-borne Aeromonas to carbapenems, as well as to investigate the presence of a metallo carbapenemase-encoding gene, named cphA. Minimum Inhibitory Concentration (MIC was determined following NCCLS standards. All the tested microorganisms were susceptible to imipenem, meropenem and biapenem. However, a strong inoculum size effect on carbapenem MICs was observed for most of the strains. Six strains, out of seven, showed the presence of metallo--beta-lactamases but cphA gene was detected in only two strains of A. veronii bv. sobria.O objetivo deste estudo foi determinar a suscetibilidade de aeromonas de origem alimentar a carbapenems bem como investigar a presença de um gene codificante de metalocarbapenemase, denominado "cph A". A suscetibilidade in vitro foi determinada pelo metodo de diluição em agar. Todas as cepas foram suscetíveis a Imipenem, Meropenem e Biapenem. Porém foi observado um forte efeito de tamanho do inóculo sobre as CIM das carbapenems na maioria das cepas. A detecção de metalo-beta-lactamase foi realizada pelo metodo lodometrico. Seis cepas das sete testadas demostraron a presença da enzima. A presença do gene cphA foi determinada por PCR e foi detectada em duas cepas de A veronii bv. sobria.

Improvement of methyl orange dye biotreatment by a novel isolated strain, Aeromonas veronii GRI, by SPB1 biosurfactant addition.

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Mnif, Inès; Maktouf, Sameh; Fendri, Raouia; Kriaa, Mouna; Ellouze, Semia; Ghribi, Dhouha

2016-01-01

Aeromonas veronii GRI (KF964486), isolated from acclimated textile effluent after selective enrichment on azo dye, was assessed for methyl orange biodegradation potency. Results suggested the potential of this bacterium for use in effective treatment of azo-dye-contaminated wastewaters under static conditions at neutral and alkaline pH value, characteristic of typical textile effluents. The strain could tolerate higher doses of dyes as it was able to decolorize up to 1000 mg/l. When used as microbial surfactant to enhance methyl orange biodecolorization, Bacillus subtilis SPB1-derived lipopeptide accelerated the decolorization rate and maximized slightly the decolorization efficiency at an optimal concentration of about 0.025%. In order to enhance the process efficiency, a Taguchi design was conducted. Phytotoxicity bioassay using sesame and radish seeds were carried out to assess the biotreatment effectiveness. The bacterium was able to effectively decolorize the azo dye when inoculated with an initial optical density of about 0.5 with 0.25% sucrose, 0.125% yeast extract, 0.01% SPB1 biosurfactant, and when conducting an agitation phase of about 24 h after static incubation. Germination potency showed an increase toward the nonoptimized conditions indicating an improvement of the biotreatment. When comparing with synthetic surfactants, a drastic decrease and an inhibition of orange methyl decolorization were observed in the presence of CTAB and SDS. The nonionic surfactant Tween 80 had a positive effect on methyl orange biodecolorization. Also, studies ensured that methyl orange removal by this strain could be due to endocellular enzymatic activities. To conclude, the addition of SPB1 bioemulsifier reduced energy costs by reducing effective decolorization period, biosurfactant stimulated bacterial decolorization method may provide highly efficient, inexpensive, and time-saving procedure in treatment of textile effluents.

X-ray Absorption Spectroscopy of the Zinc-Binding Sites in the Class B2 Metallo-B-lactamsase ImiS from Aeromonas veronii bv. sobria

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Costello,A.; Sharma, N.; Yang, K.; Crowder, M.; Tierney, D.

2006-01-01

X-ray absorption spectroscopy was used to investigate the metal-binding sites of ImiS from Aeromonas veronii bv. sobria in catalytically active (1-Zn), product-inhibited (1-Zn plus imipenem), and inactive (2-Zn) forms. The first equivalent of zinc(II) was found to bind to the consensus Zn{sub 2} site. The reaction of 1-Zn ImiS with imipenem leads to a product-bound species, coordinated to Zn via a carboxylate group. The inhibitory binding site of ImiS was examined by a comparison of wild-type ImiS with 1 and 2 equiv of bound zinc. 2-Zn ImiS extended X-ray absorption fine structure data support a binding site that is distant from the active site and contains both one sulfur donor and one histidine ligand. On the basis of the amino acid sequence of ImiS and the crystal structure of CphA [Garau et al. (2005) J. Mol. Biol. 345, 785-795], we propose that the inhibitory binding site is formed by M146, found on the B2-distinct {alpha}3 helix, and H118, a canonical Zn{sub 1} ligand, proposed to help activate the nucleophilic water. The mutation of M146 to isoleucine abolishes metal inhibition. This is the first characterization of ImiS with the native metal Zn and establishes, for the first time, the location of the inhibitory metal site.

Identificação e resistência a antimicrobianos de espécies de Aeromonas móveis isoladas de peixes e ambientes aquáticos Identification and antimicrobial resistance of motile Aeromonas isolated from fish and aquatic environment

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Daniela Hirsch

2006-12-01

Full Text Available Com o objetivo de se verificar a diversidade de espécies de Aeromonas móveis e seu perfil de susceptibilidade a antimicrobianos em pisciculturas comerciais, foram selecionadas oito tilapiculturas localizadas na região do Alto Rio Grande, Minas Gerais. De cada propriedade foram coletadas três amostras de peixes em estádio de pré-abate (vivos e saudáveis, uma amostra de água do tanque e uma amostra da água de abastecimento do sistema. De cada peixe foram coletadas amostras de lavado superficial e do parênquima renal. Diluições seriadas adequadas de cada amostra foram plaqueadas em TSA-ampicilina (10 mg/l e as amostras de rim em Ágar Sangue de cavalo a 5%. A partir de colônias isoladas positivas para o teste da oxidase foram realizados testes para identificação do gênero (testes presuntivos e das espécies de Aeromonas (testes bioquímicos. O perfil de antibiograma foi obtido pelo teste de difusão de discos de antibióticos em Ágar Mueller Hinton. Foram obtidos 75 isolados diferenciados em nove espécies de Aeromonas: A. jandaei, A. hydrophila, A. trota, A. caviae, A. sobria, A. eucrenophila, A. veronii bt veronii, A. schubertii, A. media, além de amostras classificadas como Aeromonas atípicas. Do total isolado, oito amostras foram provenientes da superfície corpórea de peixes, 14 da água de abastecimento e 53 da água do tanque. Não houve isolamento a partir dos espécimes de parênquima renal. Em relação ao perfil de resistência, 93% dos isolados foram resistentes à eritromicina, 36% à tetraciclina, 13% ao ác. nalidíxico, 9% à gentamicina, 8% à nitrofurantoína, 8% à canamicina, 5% à norfloxacina, 4% ao cloranfenicol e 3% às sulfonamidas. Dentre os isolados analisados, 43% apresentaram índice de múltipla resistência a antimicrobianos (MAR igual ou superior a 22%, ou seja, resistência a dois ou mais drogas das nove testadas. Os dados apontam para um risco iminente, tanto pelo isolamento de amostras

Diversity and homogeneity among small plasmids of Aeromonas salmonicida subsp. salmonicida linked with geographical origin

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Sabrina A Attéré

2015-11-01

Full Text Available Furunculosis, which is caused by Aeromonas salmonicida subsp. salmonicida, is a major salmonid disease in fish farms worldwide. Several plasmids found in this bacterium confer phenotypes such drug resistance and virulence. Small plasmids (pAsa1, pAsa2, pAsa3, and pAsal1 related to ColE1- and ColE2-type replicons are usually present in its normal plasmidome. In the present study, with the objective to investigate if these plasmids display particularities related to the origin of the isolates bearing them, a total of 153 isolates, including 78 new and 75 previously described, were analyzed for the presence of small plasmids by PCR and DNA restriction fragment profiling. A geographical dichotomy between Canadian and European isolates for their propensity to do not have pAsa3 or pAsal1 was found. In addition, the genotyping analysis led to the identification of two European isolates harboring an unusual pAsal1. An investigation by next-generation sequencing (NGS of these two isolates shed light on two pAsal1 variants (pAsal1C and pAsal1D. As with pAsal1B, another pAsal1 variant previously described, these two new variants bore a second insertion sequence (ISAS5 in addition to the usual ISAS11. The characterization of these variants suggested that they could predominate over the wild-type pAsal1 in stressful conditions such as growth at temperatures of 25°C and above. To obtain a comprehensive portrait of the mutational pressure on small plasmids, 26 isolates whose DNA had been sequenced by NGS were investigated. pAsa3 and pAsal1 were more prone to mutations than pAsa1 and pAsa2, especially in the mobA gene, which encodes a relaxase and a primase. Lastly, the average copy number of each plasmid per cell was assessed using raw sequencing data. A clear trend with respect to the relative proportion per cell of each plasmid was identified. Our large-scale study revealed a geographical dichotomy in small plasmid repertoire in addition to a clear trend

Genospecies and virulence factors of Aeromonas species in different sources in a North African country

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Khalifa Sifaw Ghenghesh

2014-09-01

Full Text Available Introduction: Aeromonads of medical importance have been reported from numerous clinical, food, and water sources, but identification of genospecies and virulence factors of Aeromonas species from countries in North Africa and the Middle East are few. Methods: In total 99 Aeromonas species isolates from different sources (diarrheal children [n=23], non-diarrheal children [n=16], untreated drinking water from wells [n=32], and chicken carcasses [n=28] in Tripoli, Libya, were included in the present investigation. Genus identification was confirmed by biochemical analysis, and genospecies were determined using a combination of 16S rDNA variable region and gyrB sequence analysis. Polymerase chain reaction (PCR was used to detect genes encoding toxins from 52 of the isolates. Results: We identified 44 isolates (44% as A. hydrophila (3 [3.0%] subspecies anaerogenes, 23 [23%] subspecies dhakensis, and 18 [18%] subspecies ranae; 27 isolates (27% as A. veronii; 23 isolates (23% as A. caviae; and 5 isolates (5.0% as other genospecies. The genes encoding aerolysin (aer, cytolytic enterotoxin (act, and A. hydrophila isolate SSU enterotoxin (ast were detected in 45 (87%, 4 (7.7%, and 9 (17% of the 52 isolates tested, respectively. The gene encoding an extracellular lipase (alt was not detected. Conclusion: The majority of aeromonads from Libya fall within three genospecies (i.e. A. hydrophila, A. veronii, and A. caviae, and genes coding for toxin production are common among them.

Potential enterotoxicity and antimicrobial resistance pattern of Aeromonas species isolated from pet turtles and their environment.

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Wimalasena, S H M P; Shin, Gee-Wook; Hossain, Sabrina; Heo, Gang-Joon

2017-05-23

To investigate the potential enterotoxicity and antimicrobial resistance of aeromonads from pet turtles as a risk for human infection, one hundred and two Aeromonas spp. were isolated from the feces, skin and rearing environments of pet turtles and identified by biochemical and gyrB sequence analyses. Aeromonas enteropelogenes was the predominant species among the isolates (52.9%) followed by A. hydrophila (32.4%), A. dharkensis (5.9%), A. veronii (4.9%) and A. caviae (3.9%). Their potential enterotoxicities were evaluated by PCR assays for detecting genes encoding cytotoxic enterotoxin (act) and two cytotonic enterotoxins (alt and ast). 75.8% of A. hydrophila isolates exhibited the act + /alt + /ast + genotype, whereas 94.4% of A. enteropelogenes isolates were determined to be act - /alt - /ast - . In an antimicrobial susceptibility test, most isolates were susceptible to all tested antibiotics except amoxicillin, ampicillin, cephalothin, chloramphenicol and tetracycline. Non-susceptible isolates to penicillins (ampicillin and amoxicillin) and fluoroquinolones (ciprofloxacin and norfloxacin) were frequently observed among the A. enteropelogenes isolates. Few isolates were resistant to imipenem, amikacin, ceftriaxone and cefotaxime. Collectively, these results suggest that pet turtles may pose a public health risk of infection by enterotoxigenic and antimicrobial resistant Aeromonas strains.

A molecular study on the prevalence and virulence potential of Aeromonas spp. recovered from patients suffering from diarrhea in Israel.

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Yigal Senderovich

Full Text Available BACKGROUND: Species of the genus Aeromonas are native inhabitants of aquatic environments and have recently been considered emerging human pathogens. Although the gastrointestinal tract is by far the most common anatomic site from which aeromonads are recovered, their role as etiologic agents of bacterial diarrhea is still disputed. Aeromonas-associated diarrhea is a phenomenon occurring worldwide; however, the exact prevalence of Aeromonas infections on a global scale is unknown. METHODOLOGY/PRINCIPAL FINDINGS: The prevalence and virulence potential of Aeromonas in patients suffering from diarrhea in Israel was studied using molecular methods. 1,033 diarrheal stools were sampled between April and September 2010 and Aeromonas species were identified in 17 (∼2% patients by sequencing the rpoD gene. Aeromonas species identity and abundance was: A. caviae (65%, A. veronii (29% and Aeromonas taiwanensis (6%. This is the first clinical record of A. taiwanensis as a diarrheal causative since its recent discovery from a wound infection in a patient in Taiwan. Most of the patients (77% from which Aeromonas species were isolated were negative for any other pathogens. The patients ranged from 1 to 92 years in age. Aeromonas isolates were found to possess different virulence-associated genes: ahpB (88%, pla/lip/lipH3/apl-1 (71%, act/hlyA/aerA (35%, alt (18%, ast (6%, fla (65%, lafA (41%, TTSS ascV (12%, TTSS ascF-ascG (12%, TTSS-dependent ADP-ribosylating toxins aexU (41% and aexT (6% in various combinations. Most of the identified strains were resistant to beta-lactam antibiotics but susceptible to third-generation cephalosporin antibiotics. CONCLUSIONS: Aeromonas may be a causative agent of diarrhea in patients in Israel and therefore should be included in routine bacteriological screenings.

Diversity and antibiotic resistance of Aeromonas spp. in drinking and waste water treatment plants.

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Figueira, Vânia; Vaz-Moreira, Ivone; Silva, Márcia; Manaia, Célia M

2011-11-01

The taxonomic diversity and antibiotic resistance phenotypes of aeromonads were examined in samples from drinking and waste water treatment plants (surface, ground and disinfected water in a drinking water treatment plant, and raw and treated waste water) and tap water. Bacteria identification and intra-species variation were determined based on the analysis of the 16S rRNA, gyrB and cpn60 gene sequences. Resistance phenotypes were determined using the disc diffusion method. Aeromonas veronii prevailed in raw surface water, Aeromonas hydrophyla in ozonated water, and Aeromonas media and Aeromonas puntacta in waste water. No aeromonads were detected in ground water, after the chlorination tank or in tap water. Resistance to ceftazidime or meropenem was detected in isolates from the drinking water treatment plant and waste water isolates were intrinsically resistant to nalidixic acid. Most of the times, quinolone resistance was associated with the gyrA mutation in serine 83. The gene qnrS, but not the genes qnrA, B, C, D or qepA, was detected in both surface and waste water isolates. The gene aac(6')-ib-cr was detected in different waste water strains isolated in the presence of ciprofloxacin. Both quinolone resistance genes were detected only in the species A. media. This is the first study tracking antimicrobial resistance in aeromonads in drinking, tap and waste water and the importance of these bacteria as vectors of resistance in aquatic environments is discussed. Copyright © 2011 Elsevier Ltd. All rights reserved.

Phenotypic and Genetic Diversity of Aeromonas Species Isolated from Fresh Water Lakes in Malaysia.

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Wei Ching Khor

Full Text Available Gram-negative bacilli of the genus Aeromonas are primarily inhabitants of the aquatic environment. Humans acquire this organism from a wide range of food and water sources as well as during aquatic recreational activities. In the present study, the diversity and distribution of Aeromonas species from freshwater lakes in Malaysia was investigated using glycerophospholipid-cholesterol acyltransferase (GCAT and RNA polymerase sigma-factor (rpoD genes for speciation. A total of 122 possible Aeromonas strains were isolated and confirmed to genus level using the API20E system. The clonality of the isolates was investigated using ERIC-PCR and 20 duplicate isolates were excluded from the study. The specific GCAT-PCR identified all isolates as belonging to the genus Aeromonas, in agreement with the biochemical identification. A phylogenetic tree was constructed using the rpoD gene sequence and all 102 isolates were identified as: A. veronii 43%, A. jandaei 37%, A. hydrophila 6%, A. caviae 4%, A. salmonicida 2%, A. media 2%, A. allosaccharophila 1%, A. dhakensis 1% and Aeromonas spp. 4%. Twelve virulence genes were present in the following proportions--exu 96%, ser 93%, aer 87%, fla 83%, enolase 70%, ela 62%, act 54%, aexT 33%, lip 16%, dam 16%, alt 8% and ast 4%, and at least 2 of these genes were present in all 102 strains. The ascV, aexU and hlyA genes were not detected among the isolates. A. hydrophila was the main species containing virulence genes alt and ast either present alone or in combination. It is possible that different mechanisms may be used by each genospecies to demonstrate virulence. In summary, with the use of GCAT and rpoD genes, unambiguous identification of Aeromonas species is possible and provides valuable data on the phylogenetic diversity of the organism.

High Prevalence of Plasmid-Mediated Quinolone Resistance and IncQ Plasmids Carrying qnrS2 Gene in Bacteria from Rivers near Hospitals and Aquaculture in China.

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Yanping Wen

Full Text Available Effluents from hospital and aquaculture are considered important sources of quinolone resistance. However, little information is available on the impact of this effluent on nearby rivers. In this study, 188 ciprofloxacin-resistant bacterial isolates obtained from rivers near hospitals and aquaculture were screened for plasmid-mediated quinolone resistance (PMQR genes. Species identification, antibiotic susceptibility testing, and PMQR gene transferability assessment were conducted for PMQR-positive bacteria. Representative qnrS2-encoding plasmids were subsequently sequenced using a primer-walking approach. In total, 44 isolates (23.4% were positive for qnr genes (16 qnrB2, 3 qnrS1, and 25 qnrS2 and 32 isolates (17.0% were positive for aac(6'-Ib-cr. Other PMQR genes were not detected. The qnrB2 and aac(6'-Ib-cr genes had a higher prevalence in aquaculture samples than in hospital samples, and were significantly associated with Enterobacteriaceae (p < 0.05. In contrast, the prevalence of qnrS2 was not site-related, but was significantly associated with Aeromonas spp. (p < 0.05. All PMQR isolates were resistant to three or more classes of antibiotics. Eleven qnrS2-harboring plasmids from Aeromonas spp., including a novel conjugative plasmid pHP18, were selected for sequencing. These plasmids were small in size (6,388-16,197 bp and belonged to the IncQ or IncU plasmid family, with qnrS2 being part of a mobile insertion cassette. Taken together, our findings suggest that aquaculture is a possible source for aac(6'-Ib-cr and qnrB2 dissemination, and demonstrate the ubiquity of qnrS2 in aquatic environments. Finally, Aeromonas spp. served as vectors for qnrS2 with the help of IncQ-type plasmids.

Evidence of Increased Antibiotic Resistance in Phylogenetically-Diverse Aeromonas Isolates from Semi-Intensive Fish Ponds Treated with Antibiotics.

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Patil, Hemant J; Benet-Perelberg, Ayana; Naor, Alon; Smirnov, Margarita; Ofek, Tamir; Nasser, Ahmed; Minz, Dror; Cytryn, Eddie

2016-01-01

cluster that harbored all characterized fish skin ulcer samples. Subsequent to stocking, diversity was much lower and most water column isolates in both facilities segregated into an A. veronii -associated cluster. This study demonstrated a strong correlation between aquaculture, Aeromonas diversity and antibiotic resistance. It provides strong evidence for linkage between prophylactic and systemic use of antibiotics in aquaculture and the propagation of antibiotic resistance.

Insight into the mobilome of Aeromonas strains.

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Piotrowska, Marta; Popowska, Magdalena

2015-01-01

The mobilome is a pool of genes located within mobile genetic elements (MGE), such as plasmids, IS elements, transposons, genomic/pathogenicity islands, and integron-associated gene cassettes. These genes are often referred to as "flexible" and may encode virulence factors, toxic compounds as well as resistance to antibiotics. The phenomenon of MGE transfer between bacteria, known as horizontal gene transfer (HGT), is well documented. The genes present on MGE are subject to continuous processes of evolution and environmental changes, largely induced or significantly accelerated by man. For bacteria, the only chance of survival in an environment contaminated with toxic chemicals, heavy metals and antibiotics is the acquisition of genes providing the ability to survive in such conditions. The process of acquiring and spreading antibiotic resistance genes (ARG) is of particular significance, as it is important for the health of humans and animals. Therefore, it is important to thoroughly study the mobilome of Aeromonas spp. that is widely distributed in various environments, causing many diseases in fishes and humans. This review discusses the recently published information on MGE prevalent in Aeromonas spp. with special emphasis on plasmids belonging to different incompatibility groups, i.e., IncA/C, IncU, IncQ, IncF, IncI, and ColE-type. The vast majority of plasmids carry a number of different transposons (Tn3, Tn21, Tn1213, Tn1721, Tn4401), the 1st, 2nd, or 3rd class of integrons, IS elements (e.g., IS26, ISPa12, ISPa13, ISKpn8, ISKpn6) and encode determinants such as antibiotic and mercury resistance genes, as well as virulence factors. Although the actual role of Aeromonas spp. as a human pathogen remains controversial, species of this genus may pose a serious risk to human health. This is due to the considerable potential of their mobilome, particularly in terms of antibiotic resistance and the possibility of the horizontal transfer of resistance genes.

Insight into the mobilome of Aeromonas strains

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Marta ePiotrowska

2015-05-01

Full Text Available The mobilome is a pool of genes located within mobile genetic elements (MGE, such as plasmids, IS elements, transposons, genomic/pathogenicity islands, and integron-associated gene cassettes. These genes are often referred to as flexible and may encode virulence factors, toxic compounds as well as resistance to antibiotics. The phenomenon of MGE transfer between bacteria, known as horizontal gene transfer (HGT, is well documented. The genes present on MGE are subject to continuous processes of evolution and environmental changes, largely induced or significantly accelerated by man. For bacteria, the only chance of survival in an environment contaminated with toxic chemicals, heavy metals and antibiotics is the acquisition of genes providing the ability to survive in such conditions. The process of acquiring and spreading antibiotic resistance genes (ARG is of particular significance, as it is important for the health of humans and animals. Therefore, it is important to thoroughly study the mobilome of Aeromonas spp. that is widely distributed in various environments, causing many diseases in fishes and humans. This review discusses the recently published information on MGE prevalent in Aeromonas spp. with special emphasis on plasmids belonging to different incompatibility groups, i.e., IncA/C, IncU, IncQ, IncF, IncI and ColE-type. The vast majority of plasmids carry a number of different transposons (Tn3, Tn21, Tn1213, Tn1721, Tn4401, the 1st, 2nd or 3rd class of integrons, IS elements (e.g. IS26, ISPa12, ISPa13, ISKpn8, ISKpn6 and encode determinants such as antibiotic and mercury resistance genes, as well as virulence factors. Although the actual role of Aeromonas spp. as a human pathogen remains controversial, species of this genus may pose a serious risk to human health. This is due to the considerable potential of their mobilome, particularly in terms of antibiotic resistance and the possibility of the horizontal transfer of resistance

Characterization of atypical Aeromonas salmonicida isolates by ribotyping and plasmid profiling

DEFF Research Database (Denmark)

Pedersen, Karl; Dalsgaard, Inger; Larsen, J.L.

1996-01-01

A total of 38 strains of atypical Aeromonas salmonicida, three oxidase-negative but otherwise typical Aer. salmonicida, three typical Aer. salmonicida, and two reference strains, isolated from several countries and fish species were examined with respect to rRNA gene restriction patterns (ribotypes...

Infections following the application of leeches: two case reports and review of the literature

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Maetz Benjamin

2012-10-01

Full Text Available Abstract Introduction Since the 1980s, leeches have been ingeniously used in the management of venous flap congestion. The presence of anticoagulative substances in their saliva improves the blood drainage. Their digestive tract contains several bacterial species, the main ones being Aeromonas hydrophila and Aeromonas veronii biovar sobria, which contribute to the digestion of ingested blood. These bacteria can be the cause of infections. Case presentation We report two cases of septicemia related to Aeromonas veronii biovar sobria that presented after leeches had been applied to congested transverse rectus abdominis myocutaneous flaps for delayed mammary reconstructions. Patient number 1 was a 55-year-old Caucasian woman who underwent a delayed breast reconstruction procedure. On the sixth postoperative day she showed a clinical presentation of septicemia. Aeromonas veronii biovar sobria was identified in the patient’s skin and blood bacteriological samples. Her fever ceased after 4 days of antibiotic treatment. Patient number 2 was a 56-year-old Caucasian woman who underwent a delayed breast reconstruction procedure. On the seventh postoperative day we noticed that she showed a clinical presentation of septicemia. Aeromonas veronii biovar sobria was identified in the patient’s blood cultures and local bacteriological samples. An antibiogram showed resistance to amoxicillin/clavulanic acid. Her fever ceased on the eleventh postoperative day after 4 days of antibiotic treatment. Conclusion The rate of infection after application of leeches is not negligible. The concentration of Aeromonas inside the digestive tracts of leeches largely decreases when the patient is under antibiotic therapy. These germs are sensitive to third-generation cephalosporins and fluoroquinolones and resistant to amoxicillin/clavulanic acid. We recommend preventive treatment based on classical measures of asepsis and on oral antibioprophylaxy with a fluoroquinolone

Aspects of constitutive and acquired antibioresistance in Aeromonas hydrophila strains isolated from water sources.

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Balotescu, Carmen; Israil, Anca; Radu, Roxana; Alexandru, Ionela; Dobre, Georgeta

2003-01-01

Over the last three decades, the literature pointed out the implications of Aeromonas species in human pathology. These species were described as being involved in intestinal (several outbreaks of acute gastroenteritis of choleric/dysenteric form or chronic diarrhoea, ulcerative colitis, etc.) in normal adults or children, as well as in extraintestinal infections in immunocompromised hosts. This last aspect included a large range of cutaneous injuries (micronecrosis, abscesses, bums, cellulites, furunculosis), joint, bones, respiratory, urinary tract, ocular infections up to meningitis, endocarditis, peritonitis, hepatobilliary disease, endotoxic shock and septicemia (as consequence of leech microvascular surgery). During the last decade, the literature reported a high mortality in Aeromonas infections determined by certain phenospecies (A. hydrophila and A. veronii) especially in extraintestinal infections in immunocompromised patients. In microbiologists' opinion this high rate of mortality was probably due to poor knowledge concerning the aspects of antibioresistance in Aeromonas strains, to empiric treatments with antibiotics to which these bacteria exhibiting constitutive resistance lead to insuccessful results, and at last to the increasing trend of aeromonads resistance to certain antibiotics after 1996. The literature mentioned also that for a great number of Beta-lactamase producing Aeromonas strains, the use of microdilution method (by comparison to disk diffusion in agar medium) giving false results made more difficult the true knowledge of Aeromonas antibioresistance patterns. At the same time, in 2002, the literature mentioned 4 ecological compartments considered as "reservoirs for dissemination and transfer of microbial antibioresistance i.e. humans, animals, plants and natural soil and water. In the last time, more and more data of the literature revealed that some bacteria with role of reservoir of antibioresistance in the natural environment, even

Resistensi Bakteri Aeromonas sp. Isolat Ikan Piranha (Pygosentrus nattereri Bali Safari And Marine Park terhadap Antibiotik

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Ni Made Herawati

2013-11-01

Full Text Available Normal 0 false false false EN-US X-NONE X-NONE Piranha (Pygosentrus nattereri is a fish that has been conserved at Conservation Center of Bali Safari and Marine Park. In May 2012 there was a case that twelve Piranhas suffered from illness and two of them died without any specific clinical signs. The dead Piranhas were necropsied and the tissues or parts of organs were collected for microbial examination interests. Spesies specific bacterial examination was also included using Microgen GNA TM + B-ID system test The bacterial examination found that the fishes were infected by Aeromonas hydropila and Aeromonas veronii. Further examination about antibiotic resistance tests showed that those Aeromonas spp were resistant to chloramphenicol and a combination of trimethoprim and sulphamethoxazole. It can be suggested that, next, the usage of other antibiotics is strongly recommended for the case of Piranha infected by Aeromonas spp at Bali Safari and Marine Park. /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; text-align:justify; line-height:150%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin;}

Evidence of increased antibiotic resistance in phylogenetically-diverse Aeromonas isolates from semi-intensive fish ponds treated with antibiotics

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Hemant J Patil

2016-11-01

identified, including an A. salmonicida cluster that harbored all characterized fish skin ulcer samples. Subsequent to stocking diversity was much lower and most water column isolates in both facilities segregated into an A. veronii-associated cluster. This study demonstrated a strong correlation between aquaculture, Aeromonas diversity and antibiotic resistance. It provides strong evidence for linkage between prophylactic and systemic use of antibiotics in aquaculture and the propagation of antibiotic resistance.

Occurrence and Variety of β-Lactamase Genes among Aeromonas spp. Isolated from Urban Wastewater Treatment Plant

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Marta Piotrowska

2017-05-01

Full Text Available Members of the genus Aeromonas that commonly occur in various aquatic ecosystems are taken into account as vectors spreading antibiotic resistance genes (ARGs in the environment. In our study strains of Aeromonas spp. (n = 104 not susceptible to ampicillin were isolated from municipal sewage of different levels of purification – raw sewage, activated sludge and treated wastewater. The crucial step of the study was the identification of β-lactamase resistance genes. The identified genes encode β-lactamases from 14 families – blaTEM, blaOXA, blaSHV, blaCTX-M, blaMOX, blaACC, blaFOX, blaGES, blaPER, blaV EB, blaKPC, cphA, imiH, and cepH. There were no significant differences in number of identified ARGs between isolation points. BlaOXA, blaFOX variants and, characteristic for Aeromonas genus, metallo-β-lactamase cphA-related genes were the most commonly identified types of β-lactam resistance determinants. Moreover, we found four extended-spectrum β-lactamases (blaSHV -11, blaCTX-M-27, blaCTX-M-98, and blaPER-4 – and seven AmpC (blaACC, blaFOX-2-like, blaFOX-3, blaFOX-4-like, blaFOX-9, blaFOX-10-like, and blaFOX-13-like types and variants of genes that had never been found among Aeromonas spp. before. Five of the β-lactamases families (blaTEM, blaOXA, blaFOX, blaV EB, and cphA were identified in all three isolation sites, which supports the hypothesis that wastewater treatment plants (WWTPs are hot spots of ARGs dissemination. The obtained ARGs sequences share high identity with previously described β-lactamases, but new variants of those genes have to be considered as well. Characterization of antibiotic susceptibility was performed using disk the diffusion method with 12 different antibiotics according to CLSI guidelines. Over 60% of the strains are unsusceptible to cefepime and chloramphenicol and the majority of the strains have a multidrug resistance phenotype (68%. Finally, analysis of plasmid profiles among the resistant strains

Inhibition of Escherichia coli O157:H7 on stainless steel using Pseudomonas veronii biofilms.

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Kim, Y; Kim, H; Beuchat, L R; Ryu, J-H

2018-05-01

We produced a Pseudomonas veronii biofilm on the surface of a stainless steel that is inhibitory to Escherichia coli O157:H7. Pseudomonas veronii strain KACC 81051BP, isolated from lettuce, readily formed biofilm on the surface of stainless steel coupons (SSCs) immersed in tryptic soy broth at 25°C. Cells showed significantly (P ≤ 0·05) enhanced tolerance to desiccation stress (43% relative humidity (RH)) and retained antimicrobial activity against E. coli O157:H7. The number of E. coli O157:H7 (control; 4·1 ± 0·1 log CFU per coupon) on sterile SSCs decreased to 2·7 ± 0·2 log CFU per coupon after exposure to 43% RH at 25°C for 48 h, while the population of E. coli O157:H7 (4·1 ± 0·0 log CFU per coupon) on SSCs containing P. veronii biofilm decreased to below the theoretical detection limit (1·5 log CFU per coupon) within 24 h. The antimicrobial biofilm produced on stainless steel may have application in preventing cross-contamination by E. coli O157:H7 on other abiotic surfaces in food-contact environments. The presence of Escherichia coli O157:H7 on environmental surfaces of food manufacturing, transportation and storage facilities is a significant food safety concern because it can result in cross-contamination of food products. In this study, we developed a Pseudomonas veronii biofilm on the surface of a stainless steel that inhibits the growth of E. coli O157:H7. Since P. veronii in biofilm resists desiccation, it provides persistent antimicrobial activity. Information presented here provides novel and practical insights to developing biological strategies to inactivate E. coli O157:H7 on diverse surfaces in food processing and handling environments. © 2018 The Society for Applied Microbiology.

The genome of Aeromonas salmonicida subsp. salmonicida A449: insights into the evolution of a fish pathogen

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Murphy Colleen

2008-09-01

Full Text Available Abstract Background Aeromonas salmonicida subsp. salmonicida is a Gram-negative bacterium that is the causative agent of furunculosis, a bacterial septicaemia of salmonid fish. While other species of Aeromonas are opportunistic pathogens or are found in commensal or symbiotic relationships with animal hosts, A. salmonicida subsp. salmonicida causes disease in healthy fish. The genome sequence of A. salmonicida was determined to provide a better understanding of the virulence factors used by this pathogen to infect fish. Results The nucleotide sequences of the A. salmonicida subsp. salmonicida A449 chromosome and two large plasmids are characterized. The chromosome is 4,702,402 bp and encodes 4388 genes, while the two large plasmids are 166,749 and 155,098 bp with 178 and 164 genes, respectively. Notable features are a large inversion in the chromosome and, in one of the large plasmids, the presence of a Tn21 composite transposon containing mercury resistance genes and an In2 integron encoding genes for resistance to streptomycin/spectinomycin, quaternary ammonia compounds, sulphonamides and chloramphenicol. A large number of genes encoding potential virulence factors were identified; however, many appear to be pseudogenes since they contain insertion sequences, frameshifts or in-frame stop codons. A total of 170 pseudogenes and 88 insertion sequences (of ten different types are found in the A. salmonicida genome. Comparison with the A. hydrophila ATCC 7966T genome reveals multiple large inversions in the chromosome as well as an approximately 9% difference in gene content indicating instances of single gene or operon loss or gain. A limited number of the pseudogenes found in A. salmonicida A449 were investigated in other Aeromonas strains and species. While nearly all the pseudogenes tested are present in A. salmonicida subsp. salmonicida strains, only about 25% were found in other A. salmonicida subspecies and none were detected in other

Biochemical characteristics, serogroups, and virulence factors of aeromonas species isolated from cases of diarrhoea and domestic water samples in Chennai

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Alavandi S

2003-01-01

Full Text Available PURPOSE: The objective of the present study was to delineate the differences between the clinical and environmental Aeromonas species with respect to their biochemical characteristics, serogrouping and virulence factors, in order to find a phenotypic marker of enteropathogenicity. METHODS: A total of 55 Aeromonas spp. inclusive of 19 isolates from cases of diarrhoea, and 36 from water samples comprising, 10 isolates of A. hydrophila, 21 isolates each of A. sobria, and A. caviae, two isolates of A. jandaei and one isolate of A. veronii were subjected to analysis of their biochemical characteristics, serogrouping, and virulence factors. RESULTS: Among the differences recorded in the biochemical characteristics in the three major species, the most striking characteristic was fermentation of lactose, which was observed in all the 11 A. caviae isolates recovered from water samples. None of the 10 clinical isolates of A. caviae tested fermented lactose. The clinical Aeromonas isolates belonged to seven typable serogroups, O:13, O:14, O:16, O:21, O:27, O:32 and O:35. The environmental isolates belonged to eight different serogroups, such as, O:3, O:11, O:14, O:16, O:18, O:28, O:64 and O:78 and were predominated by serotypes O:18 and O:64. Among the virulence factors tested, 89% of the environmental isolates produced b haemolysin, while only 62.3% of clinical isolates were able to do so. There was no significant difference between the clinical and environmental aeromonads with respect to their enterotoxigenicity in suckling mice in vivo, cytotoxicity in vitro in Vero cell monolayers, and ability to produce siderophores. CONCLUSION: Efforts to delineate the differences between the clinical and environmental Aeromonas spp. did not reveal significant difference between them. However, difference was observed with respect to their ability to produce b haemolysin, wherein, higher percentage of environmental isolates was haemolytic. The results also suggest

Characterization of Aeromonas hydrophila wound pathotypes by comparative genomic and functional analyses of virulence genes.

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Grim, Christopher J; Kozlova, Elena V; Sha, Jian; Fitts, Eric C; van Lier, Christina J; Kirtley, Michelle L; Joseph, Sandeep J; Read, Timothy D; Burd, Eileen M; Tall, Ben D; Joseph, Sam W; Horneman, Amy J; Chopra, Ashok K; Shak, Joshua R

2013-04-23

Aeromonas hydrophila has increasingly been implicated as a virulent and antibiotic-resistant etiologic agent in various human diseases. In a previously published case report, we described a subject with a polymicrobial wound infection that included a persistent and aggressive strain of A. hydrophila (E1), as well as a more antibiotic-resistant strain of A. hydrophila (E2). To better understand the differences between pathogenic and environmental strains of A. hydrophila, we conducted comparative genomic and functional analyses of virulence-associated genes of these two wound isolates (E1 and E2), the environmental type strain A. hydrophila ATCC 7966(T), and four other isolates belonging to A. aquariorum, A. veronii, A. salmonicida, and A. caviae. Full-genome sequencing of strains E1 and E2 revealed extensive differences between the two and strain ATCC 7966(T). The more persistent wound infection strain, E1, harbored coding sequences for a cytotoxic enterotoxin (Act), a type 3 secretion system (T3SS), flagella, hemolysins, and a homolog of exotoxin A found in Pseudomonas aeruginosa. Corresponding phenotypic analyses with A. hydrophila ATCC 7966(T) and SSU as reference strains demonstrated the functionality of these virulence genes, with strain E1 displaying enhanced swimming and swarming motility, lateral flagella on electron microscopy, the presence of T3SS effector AexU, and enhanced lethality in a mouse model of Aeromonas infection. By combining sequence-based analysis and functional assays, we characterized an A. hydrophila pathotype, exemplified by strain E1, that exhibited increased virulence in a mouse model of infection, likely because of encapsulation, enhanced motility, toxin secretion, and cellular toxicity. Aeromonas hydrophila is a common aquatic bacterium that has increasingly been implicated in serious human infections. While many determinants of virulence have been identified in Aeromonas, rapid identification of pathogenic versus nonpathogenic

Relation of chironomids with Aeromonas species

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Sivan eLaviad

2016-05-01

Full Text Available Chironomids (Diptera: Chironomidae, also known as non-biting midges, are one of the most abundant groups of insects in aquatic habitats. They undergo a complete metamorphosis of four life stages of which three are aquatic (egg, larva, pupa, and the adult emerges into the air. Chironomids serve as a natural reservoir of Aeromonas and Vibrio cholerae species. Here we review existing knowledge about the mutual relations between Aeromonas species and chironomids. Using 454-pyrosequencing of the 16S rRNA gene, we found that the prevalence of Aeromonas species in the insects’ egg masses and larvae was 1.6% and 3.3% of the insects’ endogenous microbiota, respectively. Aeromonas abundance per egg mass remained stable during a six-month period of bacterial monitoring. Different Aeromonas species were isolated and some demonstrated the ability to degrade the insect’s egg masses and to prevent eggs hatching. Chitinase was identified as the enzyme responsible for the egg mass degradation. Different Aeromonas species isolated from chironomids demonstrated the potential to protect their host from toxic metals. Aeromonas is a causative agent of fish infections. Fish are frequently recorded as feeding on chironomids. Thus, fish might be infected with Aeromonas species via chironomid consumption. Aeromonas strains are also responsible for causing gastroenteritis and wound infections in humans. Different virulence genes were identified in Aeromonas species isolated from chironomids. Chironomids may infest drinking water reservoirs, hence be the source of pathogenic Aeromonas strains in drinking water. Chironomids and Aeromonas species have a complicated mutual relationship.

Comparative genomics of the IncA/C multidrug resistance plasmid family.

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Fricke, W Florian; Welch, Timothy J; McDermott, Patrick F; Mammel, Mark K; LeClerc, J Eugene; White, David G; Cebula, Thomas A; Ravel, Jacques

2009-08-01

Multidrug resistance (MDR) plasmids belonging to the IncA/C plasmid family are widely distributed among Salmonella and other enterobacterial isolates from agricultural sources and have, at least once, also been identified in a drug-resistant Yersinia pestis isolate (IP275) from Madagascar. Here, we present the complete plasmid sequences of the IncA/C reference plasmid pRA1 (143,963 bp), isolated in 1971 from the fish pathogen Aeromonas hydrophila, and of the cryptic IncA/C plasmid pRAx (49,763 bp), isolated from Escherichia coli transconjugant D7-3, which was obtained through pRA1 transfer in 1980. Using comparative sequence analysis of pRA1 and pRAx with recent members of the IncA/C plasmid family, we show that both plasmids provide novel insights into the evolution of the IncA/C MDR plasmid family and the minimal machinery necessary for stable IncA/C plasmid maintenance. Our results indicate that recent members of the IncA/C plasmid family evolved from a common ancestor, similar in composition to pRA1, through stepwise integration of horizontally acquired resistance gene arrays into a conserved plasmid backbone. Phylogenetic comparisons predict type IV secretion-like conjugative transfer operons encoded on the shared plasmid backbones to be closely related to a group of integrating conjugative elements, which use conjugative transfer for horizontal propagation but stably integrate into the host chromosome during vegetative growth. A hipAB toxin-antitoxin gene cluster found on pRA1, which in Escherichia coli is involved in the formation of persister cell subpopulations, suggests persistence as an early broad-spectrum antimicrobial resistance mechanism in the evolution of IncA/C resistance plasmids.

Characterization of Aeromonas hydrophila Wound Pathotypes by Comparative Genomic and Functional Analyses of Virulence Genes

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Grim, Christopher J.; Kozlova, Elena V.; Sha, Jian; Fitts, Eric C.; van Lier, Christina J.; Kirtley, Michelle L.; Joseph, Sandeep J.; Read, Timothy D.; Burd, Eileen M.; Tall, Ben D.; Joseph, Sam W.; Horneman, Amy J.; Chopra, Ashok K.; Shak, Joshua R.

2013-01-01

ABSTRACT Aeromonas hydrophila has increasingly been implicated as a virulent and antibiotic-resistant etiologic agent in various human diseases. In a previously published case report, we described a subject with a polymicrobial wound infection that included a persistent and aggressive strain of A. hydrophila (E1), as well as a more antibiotic-resistant strain of A. hydrophila (E2). To better understand the differences between pathogenic and environmental strains of A. hydrophila, we conducted comparative genomic and functional analyses of virulence-associated genes of these two wound isolates (E1 and E2), the environmental type strain A. hydrophila ATCC 7966T, and four other isolates belonging to A. aquariorum, A. veronii, A. salmonicida, and A. caviae. Full-genome sequencing of strains E1 and E2 revealed extensive differences between the two and strain ATCC 7966T. The more persistent wound infection strain, E1, harbored coding sequences for a cytotoxic enterotoxin (Act), a type 3 secretion system (T3SS), flagella, hemolysins, and a homolog of exotoxin A found in Pseudomonas aeruginosa. Corresponding phenotypic analyses with A. hydrophila ATCC 7966T and SSU as reference strains demonstrated the functionality of these virulence genes, with strain E1 displaying enhanced swimming and swarming motility, lateral flagella on electron microscopy, the presence of T3SS effector AexU, and enhanced lethality in a mouse model of Aeromonas infection. By combining sequence-based analysis and functional assays, we characterized an A. hydrophila pathotype, exemplified by strain E1, that exhibited increased virulence in a mouse model of infection, likely because of encapsulation, enhanced motility, toxin secretion, and cellular toxicity. PMID:23611906

Genome-based insights into the resistome and mobilome of multidrug-resistant Aeromonas sp. ARM81 isolated from wastewater.

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Adamczuk, Marcin; Dziewit, Lukasz

2017-01-01

The draft genome of multidrug-resistant Aeromonas sp. ARM81 isolated from a wastewater treatment plant in Warsaw (Poland) was obtained. Sequence analysis revealed multiple genes conferring resistance to aminoglycosides, β-lactams or tetracycline. Three different β-lactamase genes were identified, including an extended-spectrum β-lactamase gene bla PER-1 . The antibiotic susceptibility was experimentally tested. Genome sequencing also allowed us to investigate the plasmidome and transposable mobilome of ARM81. Four plasmids, of which two carry phenotypic modules (i.e., genes encoding a zinc transporter ZitB and a putative glucosyltransferase), and 28 putative transposase genes were identified. The mobility of three insertion sequences (isoforms of previously identified elements ISAs12, ISKpn9 and ISAs26) was confirmed using trap plasmids.

Aeromonas spp.: an emerging pathogen?

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Andrea Bartolini

2015-12-01

Full Text Available The aim of this study is to identify and monitor the presence of Aeromonas spp. strains in stool cultures. We analyzed 5564 stool cultures from September 2012 to August 2013. Sixty-three patients were positive for Aeromonas spp. The most frequent symptoms were: diarrhea (46.0% and abdominal pain (12.7%. Pediatric subjects were 28. Samples’ microscopic examination showed leukocytes in 38.1% of cases. It is still controversial whether Aeromonas are responsible for human gastroenteritis, but their presence in faecies of symptomatic patients supports their etiologic role. We propose search for toxins by polymerase chain reaction to identify strains that require an antibiotic therapy.

Incidence and virulence characteristics of Aeromonas spp. in fish

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Ashraf M. Abd-El-Malek

2017-01-01

Full Text Available Aim: This study was conducted to evaluate the presence of Aeromonas spp. in raw and ready-to-eat (RTE fish commonly consumed in Assiut city, Egypt, and to determine virulence factors due to they play a key role in their pathogenicity. Materials and Methods: A total of 125 samples of raw and RTE fish samples were taken from different fish markets and fish restaurants in Assiut Governorate and screened for the presence of Aeromonas spp. by enrichment on tryptic soy broth then incubated at 30°C for 24 h. Plating unto the sterile Petri dishes containing Aeromonas agar base to which Aeromonas selective supplement was added. The plates were incubated at 37°C for 24 h. Presumptive Aeromonas colonies were biochemically confirmed and analyzed for pathogenicity by hemolysin production, protease, and lipase detection. Results: The results indicated that raw fish were contaminated with Aeromonas spp. (40% in wild and 36% in cultured Nile tilapia. Regarding RTE, Aeromonas spp. could be isolated with the percentage of 16%, 28% and 20% in fried Bolti, grilled Bolti and fried Bayad, respectively. Out of 35 isolates obtained, 22 were categorized as Aeromonas hydrophila, 12 were classified as Aeromonas sobria and Aeromonas caviae were found in only one isolate. The virulence factors of Aeromonas spp. were detected and the results showed that all isolates produced of hemolysin (91.4%, protease (77.1%, and lipase enzyme (17.1%. Conclusion: This study indicates that the presence of A. hydrophila with virulence potential in fresh and RTE fish may be a major threat to public health.

Bactérias do gênero Aeromonas em água de matadouro bovino Aeromonas bacteria in beef slaughtering water

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O.D. Rossi Jr

2000-10-01

Full Text Available Verificou-se a ocorrência de bactérias do gênero Aeromonas em amostras de água (abastecimento/residuária obtidas em matadouro bovino. Analisaram-se a água utilizada nas dependências internas, a água dos currais, utilizada na dessedentação, pré-higienização e tranqüilização dos animais e a água residuária da lavagem das carcaças. Das 30 amostras representativas de cada tipo, bactérias do gênero Aeromonas foram isoladas em 10 (33,3% amostras da água dos currais e em 10 (33,3% amostras da água residuária da lavagem de carcaças. Nenhuma das amostras da água tratada de abastecimento das instalações revelou-se positiva no isolamento. As espécies isoladas foram Aeromonas hydrophila em duas (2,2% e Aeromonas caviae em 19 (21,1% amostras. Uma cepa considerada atípica foi isolada da água dos currais. Os resultados evidenciaram que a água dos currais pode ser uma importante fonte de contaminação, principalmente para a pele, e através dela as Aeromonas sp. podem chegar à sala de matança.The aim of this work was to verify the occurrence of Aeromonas bacteria in samples of water (supply and residual collected at beef slaughterhouse. Water used at the internal facilities, water from corrals, drinking water, water for pre-hygiene and tranquilization of the animals and residual water from carcasses’ wash, were analyzed. From those 30 samples of each type, Aeromonas bacteria were isolated in 10 (33.3% samples of corral water and in 10 (33.3% samples of residual water from carcasses’ wash. None of the facilities treated water supply samples showed positive in isolation. The isolated species were Aeromonas hydrophila in two (2.2% and Aeromonas caviae in 19 (21.1% of the samples. One non-typical strain was isolated from corral water. The results demonstrated that corral water may be an important contamination source, mainly to the hide and, through it, Aeromonas sp. can reach the slaughter room.

Alkaline Peptone Water-Based Enrichment Method for mcr-3 From Acute Diarrheic Outpatient Gut Samples

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Qiaoling Sun

2018-05-01

Full Text Available A third plasmid-mediated colistin resistance gene, mcr-3, is increasingly being reported in Enterobacteriaceae and Aeromonas spp. from animals and humans. To investigate the molecular epidemiology of mcr in the gut flora of Chinese outpatients, 152 stool specimens were randomly collected from outpatients in our hospital from May to June, 2017. Stool specimens enriched in alkaline peptone water or Luria-Bertani (LB broth were screened for mcr-1, mcr-2, and mcr-3 using polymerase chain reaction (PCR-based assays. Overall, 19.1% (29/152 and 5.3% (8/152 of the stool samples enriched in alkaline peptone water were PCR-positive for mcr-1 and mcr-3, respectively, while 2.7% (4/152 of samples were positive for both mcr-1 and mcr-3. Strains isolated from the samples that were both mcr-1- and mcr-3-positive were subjected to antimicrobial susceptibility testing by broth microdilution. They were also screened for the presence of other resistance genes by PCR, while multilocus sequence typing and whole-genome sequencing were used to investigate the molecular epidemiology and genetic environment, respectively, of the resistance genes. mcr-3-positive Aeromonas veronii strain 126-14, containing a mcr-3.8-mcr-3-like2 segment, and mcr-1-positive Escherichia coli strain 126-1, belonging to sequence type 1485, were isolated from the sample from a diarrheic butcher with no history of colistin treatment. A. veronii 126-14 had a colistin minimum inhibitory concentration (MIC of 2 µg/mL and was susceptible to antibiotics in common use, while E. coli 126-1 produced TEM-1, CTX-M-55, and CTX-M-14 β-lactamases and was resistant to colistin, ceftazidime, and cefotaxime. Overall, there was a higher detection rate of mcr-3-carrying strains with low colistin MICs from the samples enriched in alkaline peptone water than from samples grown in LB broth.

Plesiomonasshigelloides and Aeromonadaceae family pathogens isolated from marine mammals of Southern and Southeastern Brazilian coast Plesiomonasshigelloides e patógenos da família Aeromonadaceae isolados de mamíferos marinhos da costa sul e sudeste do Brasil

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Christiane S. Pereira

2008-12-01

Full Text Available The aquatic environment is the habitat of many microorganisms, including Plesiomonasshigelloides and Aeromonas species which are pathogenic to human and animals. In the present investigation, we evaluated the occurrence of these pathogens from marine mammals beached or accidentally captured by fishing net in southeastern (RJ and southern (RS coastal Brazilian regions. A total of 198 swabs from 27 specimens of marine mammals, including 11 different species, were collected by DEENSP and GEMARS-CECLIMAR/UFRGS Institutes and sent to LRNCEB/IOC/FIOCRUZ. The samples were enriched in Alkaline Peptone Water (APW added with 1% of sodium chloride (NaCl, APW plus 3% NaCl and incubated at 37ºC for 18-24 hours. Following, samples were streaked onto Pseudomonas-Aeromonas Selective Agar Base (GSP Agar and suspected colonies were biochemically characterized. The results revealed 114 strains, including ten Aeromonas species and P.shigelloides. The main pathogens isolated were A.veronii biogroup veronii (19.3%, A. caviae (12.3%, A. hydrophila (9.6% and P.shigelloides (7%. The pathogens were isolated in both coastal and offshore marine mammals. These data point the importance of epidemiological surveillance and microbiological monitoring and reinforce the need to implement environmental protection programs, especially related to endangered cetacean species.O ambiente aquático é o habitat de vários microrganismos, incluindo Plesiomonasshigelloides e espécies de Aeromonas, os quais são patogênicos para o homem e os animais. Na presente investigação, foi avaliada a ocorrência destes patógenos a partir de swabs coletados de mamíferos marinhos encalhados ou capturados acidentalmente em redes de pesca nas regiões costeiras do sudeste (RJ e sul (RS do Brasil. O total de 198 swabs de 27 espécimes de mamíferos marinhos, incluindo 11 espécies distintas, foi coletado por profissionais dos institutos DEENSP, GEMARS-CECLIMAR/UFRGS e enviado ao LRNCEB

Antimicrobial resistance prevalence of Aeromonas hydrophila isolates from motile Aeromonas septicemia disease

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Kusdarwati, R.; Rozi; Dinda, N. D.; Nurjanah, I.

2018-04-01

Fish suffer, from bacteria, fungi, virus and parasites or by physical ailments. Gurami (Osphronemus gouramy), nila (Oreochromis niloticus), carp (Cyprinus carpio), catfish (Clarias sp.) were the most reported infections caused by Aeromonas are bacterial hemorrhagic septicemia or Motile Aeromonas Septicemia (MAS). Antibiotics are drugs of natural or synthetic origin that have the capacity to kill or to inhibit the growth of micro-organisms included MAS. However, the use of antibiotics in the long term can cause negative impacts, among others, feared the occurrence of bacterial resistance in certain antibiotics. The results showed five of isolates were sensitive to antibiotics of chloramphenicol, gentamycin, oxytetracycline, cefradoxil and nalidixic acid but resistant to vancomycin colistin sulphate, rifampisin, cephalosporin and novobiocin.

Antimicrobial resistance of Aeromonas hydrophila isolated from different food sources: A mini-review

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Deyan Stratev

2016-09-01

Full Text Available Summary: Aeromonas hydrophila is a Gram-negative, oxidase-positive, facultative, anaerobic, opportunistic aquatic pathogen. A. hydrophila produces virulence factors, such as hemolysins, aerolysins, adhesins, enterotoxins, phospholipase and lipase. In addition to isolation from aquatic sources, A. hydrophila has been isolated from meat and meat products, milk and dairy products, and vegetables. However, various studies showed that this opportunistic pathogen is resistant to commercial antibiotics. This is attributed to factors such as the indiscriminate use of antibiotics in aquaculture, plasmids or horizontal gene transfer. In this report, we highlight the occurrence, prevalence and antimicrobial resistance of A. hydrophila isolated from different food samples. The presence of antimicrobial-resistant A. hydrophila in food poses threats to public and aquatic animal health. Keywords: A. hydrophila, Antimicrobial resistance, Microbial food safety

Isolation and antibiotic sensitivity of Aeromonas from children with diarrhea

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Meiyanti Meiyanti

2016-02-01

Full Text Available Aeromonas species are gram-negative, motile, facultative anaerobic, rod shaped, oxidase positive bacteria of the recently assigned family Aeromonadaceae. The significance of Aeromonas species as causative agent of human diarrhoea has recently been established. The aim of the present study was to investigate the distribution, and antibiotic sensitivity of Aeromonas in nonhospitalized children with diarrhea.One hundred and seventeen rectal swabs from children with diarhhea were cultured for isolation of Aeromonas organisms as the etiological agents. In addition to Aeromonas, other enteric pathogens were also isolated. Overall, the isolates of enteric pathogens amounted to 36.8%, consisting of Salmonella, Shigella, Aeromonas, and Vibrio. Aeromonas was only found in 5.1% of cultures, with a ratio of A. caviae and A. hydrophila of 2:1, while Salmonella made up the majority of causative organisms with an isolation frequency of 18.8%, followed by Shigella with 11.1%. In this study no isolates of Vibrio cholerae O1 were found as etiological agents of diarrhea; however, V. cholerae non-O1 and V. parahaemolyticus were found in small numbers (<1%. All isolates of Aeromonas were resistant to ampicillin and tetracycline, but sensitive to ciprofloxacin and ceftriaxone, as were the other enteric pathogens. Although the frequency of isolation of these enteric pathogens was higher than for Vibrio spp., their role in infective diarrhea was less clearcut in comparison with Salmonella and Shigella.

Aeromonas caviae septicemia in immunocompetent gastrointestinal carriers

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M. Dwivedi

Full Text Available Aeromonas caviae strains have been isolated from blood and stool cultures of three immunocompetent patients, residents of Northern India, who presented with community acquired septicemia without any recent history of diarrhea. Cell culture infectivity test performed on Hep-2 cells have shown substantial degree of invasiveness in the isolated strains. This case unleashes a possibility of asymptomatic gastrointestinal carriage of such strains of A. caviae in a very large population of India, as several areas of India have very high rates of Aeromonas induced acute diarrhea/gastroenteritis (up to 13%. It needs to be appraised further in India as well as other countries having high rates of Aeromonas induced acute diarrhea/gastroenteritis.

The Genome of the Toluene-Degrading Pseudomonas veronii Strain 1YdBTEX2 and Its Differential Gene Expression in Contaminated Sand.

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Marian Morales

Full Text Available The natural restoration of soils polluted by aromatic hydrocarbons such as benzene, toluene, ethylbenzene and m- and p-xylene (BTEX may be accelerated by inoculation of specific biodegraders (bioaugmentation. Bioaugmentation mainly involves introducing bacteria that deploy their metabolic properties and adaptation potential to survive and propagate in the contaminated environment by degrading the pollutant. In order to better understand the adaptive response of cells during a transition to contaminated material, we analyzed here the genome and short-term (1 h changes in genome-wide gene expression of the BTEX-degrading bacterium Pseudomonas veronii 1YdBTEX2 in non-sterile soil and liquid medium, both in presence or absence of toluene. We obtained a gapless genome sequence of P. veronii 1YdBTEX2 covering three individual replicons with a total size of 8 Mb, two of which are largely unrelated to current known bacterial replicons. One-hour exposure to toluene, both in soil and liquid, triggered massive transcription (up to 208-fold induction of multiple gene clusters, such as toluene degradation pathway(s, chemotaxis and toluene efflux pumps. This clearly underlines their key role in the adaptive response to toluene. In comparison to liquid medium, cells in soil drastically changed expression of genes involved in membrane functioning (e.g., lipid composition, lipid metabolism, cell fatty acid synthesis, osmotic stress response (e.g., polyamine or trehalose synthesis, uptake of potassium and putrescine metabolism, highlighting the immediate response mechanisms of P. veronii 1YdBTEX2 for successful establishment in polluted soil.

The occurrence of Aeromonas in drinking water, tap water and the Porsuk River

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Merih Kivanc

2011-03-01

Full Text Available The occurrence of Aeromonas spp. in the Porsuk River, public drinking water and tap water in the City of Eskisehir (Turkey was monitored. Fresh water samples were collected from several sampling sites during a period of one year. Total 102 typical colonies of Aeromonas spp. were submitted to biochemical tests for species differentiation and of 60 isolates were confirmed by biochemical tests. Further identifications of isolates were carried out first with the VITEK system (BioMe˜rieux and then selected isolates from different phenotypes (VITEK types were identified using the DuPont Qualicon RiboPrinter® system. Aeromonas spp. was detected only in the samples from the Porsuk River. According to the results obtained with the VITEK system, our isolates were 13% Aeromonas hydrophila, 37% Aeromonas caviae, 35% Pseudomonas putida, and 15% Pseudomonas acidovorans. In addition Pseudomonas sp., Pseudomonas maltophila, Aeromonas salmonicida, Aeromonas hydrophila, and Aeromonas media species were determined using the RiboPrinter® system. The samples taken from the Porsuk River were found to contain very diverse Aeromonas populations that can pose a risk for the residents of the city. On the other hand, drinking water and tap water of the City are free from Aeromonas pathogens and seem to be reliable water sources for the community.

Genospecies and virulence factors of Aeromonas species in ...

African Journals Online (AJOL)

Introduction: Aeromonads of medical importance have been reported from numerous clinical, food, and water sources, but identification of genospecies and virulence factors of Aeromonas species from countries in North Africa and the Middle East are few. Methods: In total 99 Aeromonas species isolates from different ...

Purification and characterization of the chitosanase from Aeromonas ...

African Journals Online (AJOL)

Purification and characterization of the chitosanase from Aeromonas sp. HG08. Y Sun, J Zhang, S Wang. Abstract. In this work, the characterization of a chitosanase-producing bacterium isolated from soil was reported and this strain was grouped under the genus Aeromonas by virtue of its morphological, physiological ...

Salmonella Typhimurium ST213 is associated with two types of IncA/C plasmids carrying multiple resistance determinants.

Science.gov (United States)

Wiesner, Magdalena; Calva, Edmundo; Fernández-Mora, Marcos; Cevallos, Miguel A; Campos, Freddy; Zaidi, Mussaret B; Silva, Claudia

2011-01-11

Salmonella Typhimurium ST213 was first detected in the Mexican Typhimurium population in 2001. It is associated with a multi-drug resistance phenotype and a plasmid-borne blaCMY-2 gene conferring resistance to extended-spectrum cephalosporins. The objective of the current study was to examine the association between the ST213 genotype and blaCMY-2 plasmids. The blaCMY-2 gene was carried by an IncA/C plasmid. ST213 strains lacking the blaCMY-2 gene carried a different IncA/C plasmid. PCR analysis of seven DNA regions distributed throughout the plasmids showed that these IncA/C plasmids were related, but the presence and absence of DNA stretches produced two divergent types I and II. A class 1 integron (dfrA12, orfF and aadA2) was detected in most of the type I plasmids. Type I contained all the plasmids carrying the blaCMY-2 gene and a subset of plasmids lacking blaCMY-2. Type II included all of the remaining blaCMY-2-negative plasmids. A sequence comparison of the seven DNA regions showed that both types were closely related to IncA/C plasmids found in Escherichia, Salmonella, Yersinia, Photobacterium, Vibrio and Aeromonas. Analysis of our Typhimurium strains showed that the region containing the blaCMY-2 gene is inserted between traA and traC as a single copy, like in the E. coli plasmid pAR060302. The floR allele was identical to that of Newport pSN254, suggesting a mosaic pattern of ancestry with plasmids from other Salmonella serovars and E. coli. Only one of the tested strains was able to conjugate the IncA/C plasmid at very low frequencies (10-7 to 10-9). The lack of conjugation ability of our IncA/C plasmids agrees with the clonal dissemination trend suggested by the chromosomal backgrounds and plasmid pattern associations. The ecological success of the newly emerging Typhimurium ST213 genotype in Mexico may be related to the carriage of IncA/C plasmids. We conclude that types I and II of IncA/C plasmids originated from a common ancestor and that the

Isolation of Aeromonas caviae from yoghurt (“nono”) sold in Jos ...

African Journals Online (AJOL)

A total of 30 nono samples were collected from Farin Gada, Bauchi Road and Gangare markets in Jos and analysed for the presence of Aeromonas species. 3 (10%) of the 30 nono samples were positive for Aeromonas species; which was found to be Aeromonas caviae. All the isolates were obtained from non-heat treated ...

Interlaboratorium vergelijking van het onderzoek naar Aeromonas spp. in drinkwater (tweede onderzoek)

NARCIS (Netherlands)

Versteegh JFM; During M; Heisterkamp SH; Havelaar AH

1988-01-01

Door middel van kwantitatief onderzoek naar Aeromonas-bacterien in drie verschillende monsters water (De Bilt, De Meent en De Laak) werd een vergelijking gemaakt van de resultaten van Aeromonas onderzoek in 15 laboratoria in het kader van het deelproject: "Aeromonas in drinkwater".

Author Details

African Journals Online (AJOL)

Mousa, MA. Vol 6 (2004) - Articles Distribution, involvement and plasmid characterization of Aeromonas spp. isolated from food stuffs and human infections. Abstract PDF · Vol 6 (2004) - Articles Distribution, involvement and plasmid characterization of Aeromonas spp. isolated from foodstuffs and human infections

Susceptibility of Aeromonas Hydophila Isolates to Antimicrobial Drugs

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Igor Stojanov

2010-05-01

Full Text Available Aeromonas hydrophila is a microorganism widely distributed in nature: in water, soil, food. It is also part of the normal bacterial flora of many animals. As an opportune microorganism it is a secondary biological agent that contributes to the occurrence of a fish disease and its deterioration. Frequently, its presence is an indication of bad zoohygiene and zootechnical conditions in fish ponds. Reduced quality and quantity of feed, mechanical injuries, parasitosis, seasonal oscillation in temperature present some of the factors that produce favorable conditions for bacterial proliferation of aeromonas in fish ponds, so clinical symptoms of the disease occur. Aeromonas is almost always present in clinical isolates and may be unjustly accused for bad health of fish. Antibiotic therapy is applied even when the clinical findings are clear, what certainly effects the susceptibility to chemotherapeutics. The subject of our work was bacteriological examination of the material obtained from the carps with the observed skin changes and the carps without these changes. Also, antimicrobial susceptibility of Aeromonas hydrophila was tested. The aim of this research was to determined the presence of Aeromonas hydrophilia in the carp ponds and to test antibiotic susceptibility. The material consisted of the samples from the fish ponds where the carps were with and without changed skin. The method the isolation of Aeromonas hydrophila was used. The diffusion disk technique was used for testing antibiotic susceptibility. The isolates were tested for their susceptibility to Florephenikol, Flumequine, Olaqindox and Oxitetracycline. The obtained results point that antimicrobial susceptibility was the same regardless of the origin of the samples, i.e. the resistance was the same for both groups of samples (the strains isolated from the fish with skin changes and the strains from fish without changes on skin. The strains were highly resistant: 35% were resistant to

Quorum Sensing Regulation in Aeromonas hydrophila

DEFF Research Database (Denmark)

Garde, Christian; Bjarnsholt, Thomas; Givskov, Michael

2010-01-01

We present detailed results on the C4-HSL-mediated quorum sensing (QS) regulatory system of the opportunistic Gram-negative bacterium Aeromonas hydrophila. This bacterium contains a particularly simple QS system that allows for a detailed modeling of kinetics. In a model system (i.e., the Escheri......We present detailed results on the C4-HSL-mediated quorum sensing (QS) regulatory system of the opportunistic Gram-negative bacterium Aeromonas hydrophila. This bacterium contains a particularly simple QS system that allows for a detailed modeling of kinetics. In a model system (i...

Quantitative Recovery of Aeromonas hydrophila from Nsukka Sewage

African Journals Online (AJOL)

Sewage samples were analyzed for the recovery of Aeromonas hydrophila. The pH of the samples ranged from 8.2 - 9.6 and the temperature from 20.0 – 28.7. Samples were enriched in alkaline peptone water medium (pH 8.4) before plating on different selective media. Media tested for the recovery of Aeromonas ...

Aeromonas spp. IN PRODUCTS OF ANIMAL ORIGIN AND DRINKING WATER OF GOIÂNIA-GO Aeromonas spp. EM PRODUTOS DE ORIGEM ANIMAL E EM ÁGUA DE CONSUMO DE GOIÂNIA - GO

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Albenones José de Mesquita

2007-09-01

Full Text Available

A total of 53 samples of products from animal origin and drinking water was examined for the presence of Aeromonas spp. Aeromonas occurred in 26.41% (14/53 of the samples. The raw products showed high frequency of contamination and relatively high count Aeromonas hydrophila was the dominating species, 57.5%, being followed of A. veroni (22.5%, A. sobria (17.5% and A. media (2.5%. None of the Aeromonas spp. was isolated from chlorinated or unchlorinated drinking water.

KEY-WORDS: Aeromonas; animal origin products; drinking water.

Um total de 53 amostras de produtos de origem animal e água de consumo foi examinado para se verificar a presença de Aeromonas spp. Desse total, 14/53 (26,41% amostras foram positivas para Aeromonas. Os produtos crus apresentaram maior freqüência de contaminação e contagem relativamente elevadas. A espécie Aeromonas hydrophila foi a mais freqüente (57,5%, seguida pelas espécies A. veroni (22,5%, A. sobria (17,5% e A. media (2,5%. Nenhuma amostra de água de consumo, clorada ou não clorada, mostrou-se positiva para Aeromonas ssp.

PALAVRA-CHAVE: Aeromonas; produtos de origem animal; água de consumo.

Prevalence of Aeromonas species and Escherichia coli in stool ...

African Journals Online (AJOL)

Background: Diarrhoea is one of the main causes of mortality and morbidity in childhood. Bacterial diarrhoea is a common disorder. Aeromonas species and Escherichia coli (E. coli) are some of the aetiological agents associated with diarrhoea in children. Objective: To determine the prevalence of Aeromonas species and ...

Interlaboratorium vergelijking van het onderzoek naar Aeromonas spp. in drinkwater

NARCIS (Netherlands)

Havelaar AH; During M; Versteegh JFM

1986-01-01

Door middel van onderzoek van zes kunstmatig besmette gesimuleerde monsters drinkwater ( 4 Aeromonas spp., 1 Klebsiella oxytoca, 1 Pseudomonas aeruginosa) werd een vergelijking gemaakt van de resultaten van Aeromonas onderzoek in 14 laboratoria. De tellingen in de deelnemende laboratoria

Biological control of Aeromonas salmonicida subsp. salmonicida infection in rainbow trout (Oncorhynchus mykiss) using Aeromonas phage PAS-1.

Science.gov (United States)

Kim, J H; Choresca, C H; Shin, S P; Han, J E; Jun, J W; Park, S C

2015-02-01

The potential control efficacy of Aeromonas phage PAS-1 was evaluated against Aeromonas salmonicida subsp. salmonicida infection in rainbow trout (Oncorhynchus mykiss) model in this study. The phage was co-cultured with the virulent A. salmonicida subsp. salmonicida strain AS05 that possesses the type III secretion system (TTSS) ascV gene, and efficient bacteriolytic activity was observed against the bacteria. The administration of PAS-1 in rainbow trout demonstrated that the phage was cleared from the fish within 200 h post-administration, and a temporal neutralizing activity against the phage was detected in the sera of phage-administrated fish. The administration of PAS-1 (multiplicity of infection: 10 000) in A. salmonicida subsp. salmonicida infected rainbow trout model showed notable protective effects, with increased survival rates and mean times to death. These results demonstrated that Aeromonas phage PAS-1 could be considered as an alternative biological control agent against A. salmonicida subsp. salmonicida infections in rainbow trout culture. © 2013 Blackwell Verlag GmbH.

Importancia biosanitaria de aeromonas: Taxonomia y Epidemiologia

OpenAIRE

Soler Falgàs, Lara

2003-01-01

El género Aeromonas está constituido por bacterias Gram-negativas aisladas frecuentemente en el agua. Adquieren relevancia por estar presentes en alimentos, y ser capaces de ocasionar cuadros diarreicos e infecciones extraintestinales en el hombre, habiéndose demostrado en la presente tesis, que pueden ser las causantes de hasta el 2% de las diarreas del viajero. La taxonomía de Aeromonas es compleja. El género consta de 15 especies difíciles de identificar con métodos bioquímicos, por lo cua...

Novo meio seletivo-indicador para detecção de Aeromonas e Plesiomonas: ágar UNISC New selective indicator medium for detection of Aeromonas and Plesiomonas: UNISC agar

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Marion Pereira da Rocha

2008-08-01

Full Text Available Avaliou-se um novo meio seletivo-indicador (ágar UNISC para o isolamento de enteropatógenos clássicos e Aeromonas e Plesiomonas shigelloides. A capacidade de fermentação da xilose é indicada pela coloração amarela (fermentadores ou azul (não fermentadores que, aliada à prova da oxidase, constitui-se em indicador para a detecção de Aeromonas spp e Plesiomonas shigelloides. A produtividade e seletividade, avaliadas pelos índice de contagem absoluta e índice de contagem relativa indicam-no como uma alternativa aos coprocultivos clássicos porque permite, num só meio, o isolamento de Escherichia coli, Shigella spp, Salmonella spp, bem como, Aeromonas spp e Plesiomonas shigelloides, favorecendo o diagnóstico laboratorial das gastroenterites.We evaluated a new selective indicator medium (UNISC Agar for isolation of classical enteropathogens, Aeromonas spp and Plesiomonas shigelloides. The xylose fermentation capacity is indicated by a yellow color (fermenting agents or blue (no fermenting agent. This, together with the oxidase test, establishes it as an indicator for detecting Aeromonas and Plesiomonas shigelloides. Its productivity and selectivity, as assessed using the absolute count index and relative count index, indicate it as an alternative to the classical feces culturing media. This is because, in a single medium, it enables isolation of Escherichia coli, Shigella spp and Salmonella spp, in addition to Aeromonas and Plesiomonas shigelloides, thereby favoring the laboratory diagnosis of gastroenteritis.

J-GLOBAL MeSH Dictionary: Aeromonas salmonicida [MeCab user dictionary for science technology term[Archive

Lifescience Database Archive (English)

Full Text Available MeCab user dictionary for science technology term Aeromonas salmonicida 名詞 一般 * * * * Aeromonas salmon...icida ... MeSH D048409 200906081596351600 C LS07 UNKNOWN_2 Aeromonas salmonicida

Aeromonas caviae strain induces Th1 cytokine response in mouse intestinal tract

Science.gov (United States)

Aeromonas caviae has been associated with human gastrointestinal disease. Strains of this species typically lack virulence factors (VFs) such as enterotoxins and hemolysins that are produced by other human pathogens of the Aeromonas genus,. Microarray profiling of...

Antibacterial Effect of Gallic Acid against Aeromonas hydrophila and Aeromonas sobria Through Damaging Membrane Integrity.

Science.gov (United States)

Lu, Jing; Wang, Zhenning; Ren, Mengrou; Huang, Guoren; Fang, Baochen; Bu, Xiujuan; Liu, Yanhui; Guan, Shuang

In the study, we investigated the antibacterial activity and mechanism of gallic acid against Aeromonas hydrophila and Aeromonas sobria. Gallic acid showed strong antimicrobial activity against the two bacteria. Furthermore, the antibacterial mechanism of gallic acid (0, 3, 6, 12 mM) was performed by membrane integrity assay and scanning electron microscopy (SEM) assay. The results showed that gallic acid notably increased the released material absorption value at 260, 280 nm and electric conductivity in a dose-dependent manner. Moreover, the SEM assay showed that gallic acid induced severe shrink of bacterial intima and irregular morphology in a dose-dependent manner. The SDS-PAGE profiles further confirmed that gallic acid could damage bacterial cells. These results indicated gallic acid exhibited antibacterial effect by destroying membrane integrity of A. hydrophila and A. sobria. Hence, gallic acid has great potential as a new natural food preservative in food fresh-keeping and storage.

Aeromonas presence in drinking water from collective reservoirs and wells in peri-urban area in Brazil

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Maria Tereza Pepe Razzolini

2010-10-01

Full Text Available Aeromonas genus is considered an emerging pathogen and its presence in drinking water supplies is a reason to public health concern. This study investigated the occurrence of Aeromonas in samples from collective reservoirs and wells used as drinking water sources in a peri-urban area. A total of 35 water samples were collected from collective reservoirs and 32 from wells bimonthly, from September 2007 to September 2008. Aeromonas spp determination was carried out using a Multiple-Tube Technique. Samples were inoculated into alkaline peptone water and the superficial film formed was transferred to blood agar plates amended with ampicillin. Typical Aeromonas colonies were submitted to a biochemical screening and then to biochemical tests for species differentiation. Aeromonas was detected in 13 (19% of the 69 samples examined (6 from collective reservoirs and 7 from wells. Concentrations of Aeromonas in collective reservoirs ranged from <0.3 to 1.2 x10²MPN/100mL and, in wells, from <0.3 to 2.4 x10²MPN/100mL. The most frequent specie in the collective reservoir samples was Aeromonas spp (68%, followed by A. encheleia (14% and A. allosaccharophila (8% and A. hydrophila (8%. Aeromonas spp (87% was the most frequent specie isolated from well samples, followed by A. allosacchariphila (8%, A. encheleia (2% and A. jandaei (5%. These data show the presence and diversity of Aeromonas genus in the samples analyzed and highlight that its presence in drinking water poses a significant public health concern.

Aminoglycoside-resistant Aeromonas hydrophila as part of a polymicrobial infection following a traumatic fall into freshwater.

Science.gov (United States)

Shak, Joshua R; Whitaker, Jennifer A; Ribner, Bruce S; Burd, Eileen M

2011-03-01

Amikacin is a first-line treatment for Aeromonas infection due to high efficacy. There are few reports of aminoglycoside-resistant Aeromonas spp. We report a soft tissue infection containing multiple pathogens, including a strain of Aeromonas hydrophila resistant to amikacin, tobramycin, and multiple cephalosporins.

Aminoglycoside-Resistant Aeromonas hydrophila as Part of a Polymicrobial Infection following a Traumatic Fall into Freshwater▿

Science.gov (United States)

Shak, Joshua R.; Whitaker, Jennifer A.; Ribner, Bruce S.; Burd, Eileen M.

2011-01-01

Amikacin is a first-line treatment for Aeromonas infection due to high efficacy. There are few reports of aminoglycoside-resistant Aeromonas spp. We report a soft tissue infection containing multiple pathogens, including a strain of Aeromonas hydrophila resistant to amikacin, tobramycin, and multiple cephalosporins. PMID:21209173

Aeromonas hydrophila urinary tract infection in pregnancy- Case report and literature review

OpenAIRE

Ragunathan, Latha; Kavitha, Kannaiyan; Raveendran, Vinod; Dhandapani, Senthil Pragash; Jaget, Nirmala; Kannivelu, Jayanthi

2012-01-01

A case of a pregnant woman without previous or concomitant disease, who developed an Aeromonas hydrophila urinary tract infection (UTI) at 12 weeks gestation, is reported. A brief review of the literature on the association and incidence of Aeromonas spp in urinary infections and also in association with pregnancy is presented.

Plasmids in Gram negatives: molecular typing of resistance plasmids.

Science.gov (United States)

Carattoli, Alessandra

2011-12-01

A plasmid is defined as a double stranded, circular DNA molecule capable of autonomous replication. By definition, plasmids do not carry genes essential for the growth of host cells under non-stressed conditions but they have systems which guarantee their autonomous replication also controlling the copy number and ensuring stable inheritance during cell division. Most of the plasmids confer positively selectable phenotypes by the presence of antimicrobial resistance genes. Plasmids evolve as an integral part of the bacterial genome, providing resistance genes that can be easily exchanged among bacteria of different origin and source by conjugation. A multidisciplinary approach is currently applied to study the acquisition and spread of antimicrobial resistance in clinically relevant bacterial pathogens and the established surveillance can be implemented by replicon typing of plasmids. Particular plasmid families are more frequently detected among Enterobacteriaceae and play a major role in the diffusion of specific resistance genes. For instance, IncFII, IncA/C, IncL/M, IncN and IncI1 plasmids carrying extended-spectrum beta-lactamase genes and acquired AmpC genes are currently considered to be "epidemic resistance plasmids", being worldwide detected in Enterobacteriaceae of different origin and sources. The recognition of successful plasmids is an essential first step to design intervention strategies preventing their spread. Copyright © 2011 Elsevier GmbH. All rights reserved.

Characterization of multiple antibiotic resistance of culturable microorganisms and metagenomic analysis of total microbial diversity of marine fish sold in retail shops in Mumbai, India.

Science.gov (United States)

Naik, Onkar A; Shashidhar, Ravindranath; Rath, Devashish; Bandekar, Jayant R; Rath, Archana

2018-03-01

Marine fish species were analyzed for culturable and total metagenomic microbial diversity, antibiotic resistance (AR) pattern, and horizontal gene transfer in culturable microorganisms. We observed a high AR microbial load of 3 to 4 log CFU g -1 . Many fish pathogens like Providencia, Staphylococcus, Klebsiella pneumoniae, Enterobacter, Vagococcus, and Aeromonas veronii were isolated. Photobacterium and Vibrio were two major fish and human pathogens which were identified in the fish metagenome. Other pathogens that were identified were Shewanella, Acinetobacter, Psychrobacter, and Flavobacterium. Most of these pathogens were resistant to multiple antibiotics such as erythromycin, kanamycin, neomycin, streptomycin, penicillin, cefotaxime, bacitracin, rifampicin, trimethoprim, ciprofloxacin, and doxycycline with a high multiple antibiotic resistance index of 0.54-0.77. The fish microflora showed high prevalence of AR genes like bla TEM , Class I integron, tetA, aph(3')-IIIa, ermB, aadA, and sul1. Nineteen of 26 AR isolates harbored Class I integrons showing high co-resistance to trimethoprim, kanamycin, doxycycline, and cefotaxime. Mobile R-plasmids from 6 of the 12 AR pathogens were transferred to recipient E. coli after conjugation. The transconjugants harbored the same R-plasmid carrying bla CTX-M , dfr1, tetA, bla TEM , and cat genes. This study confirms that fish is a potential carrier of AR pathogens which can enter the human gut via food chain. To the best of our knowledge, this is the first study in the Indian subcontinent reporting a direct evidence of spread of AR pathogens to humans from specific marine fish consumption.

Sensitivity of planktonic and biofilm-associated Aeromonas spp. to ionizing radiation

International Nuclear Information System (INIS)

Nagar, Vandan; Bandekar, J.R.

2015-01-01

Genus Aeromonas has emerged as an important human pathogen because it causes a variety of diseases including gastroenteritis and extra-intestinal infections. Aeromonas have the ability to adhere and form biofilms on food surfaces and food contact surfaces. Biofilm formation on foods and food contact surfaces is the major reason for contamination, cross contamination and post-processing contamination of the final food product leading to food spoilage, product rejection, economic losses and food-borne diseases. Biofilms have shown high resistance to heat, desiccation, acidic condition, high salt concentration, antibiotics and other food preservatives. Earlier studies in our laboratory have shown that ionizing radiation effectively inactivates Aeromonas in different food products. However, the relative efficacy of this process against biofilm associated cells versus free-living planktonic cells of Aeromonas is not well documented. Therefore, the dose of gamma radiation required to reduce the population by 90% (D10) was calculated for planktonic and biofilm-associated A. salmonicida Y567 and A. hydrophila A331 cells. Both A. hydrophila A331 and A. salmonicida Y567 expressed significant ability to attach and grow on glass surface following incubation at 30℃ in TSB. Ionizing radiation effectively reduced the populations of both planktonic and biofilm-associated cells for both the strains. Mean cell counts of survivors and surviving fraction of planktonic and biofilm-associated cells decreased with increased irradiation doses. The D10 values of planktonic cells and biofilm cells for A. salmonicida (Y567) were 232.65 Gy and 248.41 Gy, respectively; whereas, the D10 values of planktonic cells and biofilm cells for A. hydrophila (A331) were 249.2 Gy and 240.2 Gy respectively. No significant difference in the D10 values of planktonic and biofilm associated Aeromonas was observed. The influence of the cultured state of the organism, i.e., planktonic versus biofilm associated

Molecular detection and antimicrobial resistance of Aeromonas from houseflies (Musca domestica in Iran

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Davood Ommi

2015-11-01

Full Text Available Objective. This study aimed to report the molecular detection and antimicrobial resistance of Aeromonas among houseflies (Musca domestica in Shahrekord and Isfahan provinces of Iran. Materials and methods. Flies were caught from household kitchens, cattle farms, animal hospitals, human hospitals, slaughter house and poultry farms and put in collection separate sterile tubes. Isolation was accomplished by culture of flies in alkaline peptone water followed by identification with Aeromonas-specific Polymerase Chain Reaction (PCR. Results. Out of 600 houseflies 73 (12.2% were infected with Aeromonas spp. Significantly higher frequencies of Aeromonas were isolated in Shahrekord province (13.0%; 39/300 than in Isfahan province (11.3%; 34/300. The recovery frequencies of the organisms were significantly lower in kitchens as compared to those in cattle farms and hospital wards which were similar. Higher proportions of infected flies were obtained during summer whereas low proportions were obtained during winter. Conclusions. It is concluded that houseflies do harbor diarrheagenic pathogens, including Aeromonas especially during summer. The carried organisms are resistant to a number of antimicrobials at different levels. Thus, future plans aimed at stemming infections caused by these organisms should take flies into account. Control efforts of infections caused by this particular bacterium should therefore take into account Musca domestica.

In Silico Detection and Typing of Plasmids using PlasmidFinder and Plasmid Multilocus Sequence Typing

DEFF Research Database (Denmark)

Carattoli, Alessandra; Zankari, Ea; García-Fernández, Aurora

2014-01-01

In the work presented here, we designed and developed two easy-to-use Web tools for in silico detection and characterization of whole-genome sequence (WGS) and whole-plasmid sequence data from members of the family Enterobacteriaceae. These tools will facilitate bacterial typing based on draft...... genomes of multidrug-resistant Enterobacteriaceae species by the rapid detection of known plasmid types. Replicon sequences from 559 fully sequenced plasmids associated with the family Enterobacteriaceae in the NCBI nucleotide database were collected to build a consensus database for integration...... sequences identified in the 559 fully sequenced plasmids. For plasmid multilocus sequence typing (pMLST) analysis, a database that is updated weekly was generated from www.pubmlst.org and integrated into a Web tool called pMLST. Both databases were evaluated using draft genomes from a collection...

Antibiotic Susceptibility Profile of Aeromonas Species Isolated from Wastewater Treatment Plant

Directory of Open Access Journals (Sweden)

Isoken H. Igbinosa

2012-01-01

Full Text Available This study assessed the prevalence of antibiotic-resistant Aeromonas species isolated from Alice and Fort Beaufort wastewater treatment plant in the Eastern Cape Province of South Africa. Antibiotic susceptibility was determined using the disc diffusion method, and polymerase chain reaction (PCR assay was employed for the detection of antibiotics resistance genes. Variable susceptibilities were observed against ciprofloxacin, chloramphenicol, nalidixic acid, gentamicin, minocycline, among others. Aeromonas isolates from both locations were 100% resistant to penicillin, oxacillin, ampicillin, and vancomycin. Higher phenotypic resistance was observed in isolates from Fort Beaufort compared to isolates from Alice. Class A pse1 β-lactamase was detected in 20.8% of the isolates with a lower detection rate of 8.3% for blaTEM gene. Class 1 integron was present in 20.8% of Aeromonas isolates while class 2 integron and TetC gene were not detected in any isolate. The antibiotic resistance phenotypes observed in the isolates and the presence of β-lactamases genes detected in some isolates are of clinical and public health concern as this has consequences for antimicrobial chemotherapy of infections associated with Aeromonas species. This study further supports wastewater as potential reservoirs of antibiotic resistance determinants in the environment.

Aeromonas hydrophila urinary tract infection in pregnancy- Case report and literature review

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Latha Ragunathan

2012-03-01

Full Text Available A case of a pregnant woman without previous or concomitant disease, who developed an Aeromonas hydrophila urinarytract infection (UTI at 12 weeks gestation, is reported. A brief review of the literature on the association and incidenceof Aeromonas spp in urinary infections and also in association with pregnancy is presented. J Microbiol Infect Dis 2012;2(1: 26-28

AEROMONAS SPP BACTEREMIA OF RAINBOW TROUT FRY (ONCORHYNCHUS MYKISS: BIOCHEMICAL CHARACTERIZATION OF THE CAUSATIVE ORGANISM AND ANTIMICROBIAL SUSCEPTIBILITY

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Damir Kapetanović

2004-09-01

Full Text Available Aeromonas hydrophila and other members of Aeromonas genus are ubiquitus in aquatic environment and make part of normal bacterial flora of rainbow trout. Aeromonas spp. infections are worldwide registered. Here we present our experience and knowledge on Aeromonas bacteremia, which causes mortality of rainbow trout fry. Rainbow trout fry, 7 month old, started to die in November 2003. Fish samples (17 samples of dead and moribund fish were delivered to the Laboratory for aquaculture. With Api 20 NE tests Aeromonas hydrophila / caviae type I was identified with an average probability of 99.9 % (one test against, as well as Aeromonas hydrophila / caviae type II with an average probability of 99.5 % (one test against from liver, spleen, kidney, intestines and damaged eye. All of isolated and identified samples were tested for antibiotic susceptibility by disc diffusion method. The test showed that specimens were most sensitive on flumequin, and relatively less sensitive on chloramphenicol and enrofloxacin. Therapy was successfully applied with Flubactin®.

Identifikasi Penyakit Aeromonad pada Budi Daya Ikan Air Tawar di Bali (IDENTIFICATION OF AEROMONAD DISEASE IN FRESH WATER AQUACULTURE IN DENPASAR, BALI

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Surya Amanu

2015-05-01

Full Text Available Fresh water and marine fish horticulture in Bali is often harmed by the outbreak of diseases such asthose caused by Aeromonas sp (aeromonad disease.Aims ofstudy were 1 to find out the primary agent ofthe aeomonad disease in the fresh water aquaculture in Bali based on conventional and molecularidentification, 2 to find out the genetic variability of Aeromonas species, 3 to determine the effectiveantibiotic against the agent. Samples of fishes were collected from 5 different locations of fresh wateraquaculture that had high number of morbidity and mortality. Many different fishes which showed clinicalsign such as skin lesion and exophthalmus were collected.Aeromonas hydrophila and A. salmonicida wereisolated and identified from fishes, they were then identified molecularly with DNA extraction, DNAamplification in 16S rRNA gene, purification and sequencing. Sequences of both Aeromonas species fromdifferent location were analysed to create the phylogenetic tree with Maximum Parsimony and NeighborJoining method. Sensitivity of 5 antibiotics to both species of Aeromonas were done to determine the bestantibiotic against the disease. Aeromonad disease were found only in 3 regions in Bali. As many as 10isolates of A.salmonicida and 11 isolates of A.hydrophila were examined. The histopathological examinationshowed dermatitis, epicarditis, retinitis, liver and kidney congestion in fish.There were two clusters ofA.salmonicida, subspecies smithiaand subspecies achromogenes.Aeromomas hydrophyla had a close relationwith A. veronii.Aeromonas salmonicida subspecies salmonicida has not been found in Bali. Enrofloxacineand gentamycin was the best antibiotic for treating the Aeromonad disease which were more effective ascompared to3 other antibiot ics (Ampicillin, Doxycycline, and Eritromycin.

Aeromonas salmonicida bacteremia associated with chronic well water consumption in a patient with diabetes

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Christine Ann Moore

2017-01-01

Full Text Available Aeromonas salmonicida is associated with superficial skin infections in fish. Its virulence factors allow colonization of water including surface water such as salt water, beaches, and fresh water wells. Moreover, it is possible for immunocompromised patients to develop invasive disease after chronic exposure to Aeromonas spp. through contaminated water. While there are reports of Aeromonas spp. bacteremia following water ingestion, there have been no reports of A. salmonicida bacteremia from water consumption. We report the first case of A. salmonicida bacteremia in a patient with diabetes due to chronic consumption of well water.

AEROMONAS SALMONICIDA INFECTION IN VACCINATED RAINBOW TROUT

DEFF Research Database (Denmark)

Chettri, Jiwan Kumar; Skov, Jakob; Mohammad, Rezkar Jaafar

In vivo testing of any candidate vaccine is influenced by the choice of challenge method and the external environmental conditions. In the present study, a comparative challenge study was performed to evaluate the efficacy of different vaccines against the bacterial pathogen Aeromonas salmonicida...

Evolutionary Roots and Diversification of the Genus Aeromonas.

Science.gov (United States)

Sanglas, Ariadna; Albarral, Vicenta; Farfán, Maribel; Lorén, J G; Fusté, M C

2017-01-01

Despite the importance of diversification rates in the study of prokaryote evolution, they have not been quantitatively assessed for the majority of microorganism taxa. The investigation of evolutionary patterns in prokaryotes constitutes a challenge due to a very scarce fossil record, limited morphological differentiation and frequently complex taxonomic relationships, which make even species recognition difficult. Although the speciation models and speciation rates in eukaryotes have traditionally been established by analyzing the fossil record data, this is frequently incomplete, and not always available. More recently, several methods based on molecular sequence data have been developed to estimate speciation and extinction rates from phylogenies reconstructed from contemporary taxa. In this work, we determined the divergence time and temporal diversification of the genus Aeromonas by applying these methods widely used with eukaryotic taxa. Our analysis involved 150 Aeromonas strains using the concatenated sequences of two housekeeping genes (approximately 2,000 bp). Dating and diversification model analyses were performed using two different approaches: obtaining the consensus sequence from the concatenated sequences corresponding to all the strains belonging to the same species, or generating the species tree from multiple alignments of each gene. We used BEAST to perform a Bayesian analysis to estimate both the phylogeny and the divergence times. A global molecular clock cannot be assumed for any gene. From the chronograms obtained, we carried out a diversification analysis using several approaches. The results suggest that the genus Aeromonas began to diverge approximately 250 millions of years (Ma) ago. All methods used to determine Aeromonas diversification gave similar results, suggesting that the speciation process in this bacterial genus followed a rate-constant (Yule) diversification model, although there is a small probability that a slight

Evaluation of different conditions and culture media for the recovery of Aeromonas spp. from water and shellfish samples.

Science.gov (United States)

Latif-Eugenín, F; Beaz-Hidalgo, R; Figueras, M J

2016-09-01

To perform a comparative study for determining the optimum culture method (direct plating or enrichment) and medium (ampicillin dextrin agar (ADA), starch ampicillin agar (SAA), bile salts irgasan brilliant green modified (BIBG-m)) for recovering Aeromonas species from water and shellfish samples. By direct culture, Aeromonas was detected in 65% (13/20) of the water samples and in 54·5% (6/11) of the shellfish samples. However, when a pre-enrichment step was included, the number of positive water samples increased to 75% (15/20) and the ones of shellfish to 90·1% (10/11). The enriched culture significantly favoured (P culture medium for detecting Aeromonas from water was ADA. However, no differences were observed in the case of shellfish samples (P > 0·05). Isolation of Aeromonas media from water was favoured (P culture method and medium used influenced the recovery of some Aeromonas species from water and shellfish samples. This fact should be considered in future prevalence studies to avoid overestimating the above mentioned Aeromonas species. © 2016 The Society for Applied Microbiology.

Analysis of the Genome and Mobilome of a Dissimilatory Arsenate Reducing Aeromonas sp. O23A Reveals Multiple Mechanisms for Heavy Metal Resistance and Metabolism

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Witold Uhrynowski

2017-05-01

Full Text Available Aeromonas spp. are among the most ubiquitous microorganisms, as they have been isolated from different environmental niches including waters, soil, as well as wounds and digestive tracts of poikilothermic animals and humans. Although much attention has been paid to the pathogenicity of Aeromonads, the role of these bacteria in environmentally important processes, such as transformation of heavy metals, remains to be discovered. Therefore, the aim of this study was a detailed genomic characterization of Aeromonas sp. O23A, the first representative of this genus capable of dissimilatory arsenate reduction. The strain was isolated from microbial mats from the Zloty Stok mine (SW Poland, an environment strongly contaminated with arsenic. Previous physiological studies indicated that O23A may be involved in both mobilization and immobilization of this metalloid in the environment. To discover the molecular basis of the mechanisms behind the observed abilities, the genome of O23A (∼5.0 Mbp was sequenced and annotated, and genes for arsenic respiration, heavy metal resistance (hmr and other phenotypic traits, including siderophore production, were identified. The functionality of the indicated gene modules was assessed in a series of minimal inhibitory concentration analyses for various metals and metalloids, as well as mineral dissolution experiments. Interestingly, comparative analyses revealed that O23A is related to a fish pathogen Aeromonas salmonicida subsp. salmonicida A449 which, however, does not carry genes for arsenic respiration. This indicates that the dissimilatory arsenate reduction ability may have been lost during genome reduction in pathogenic strains, or acquired through horizontal gene transfer. Therefore, particular emphasis was placed upon the mobilome of O23A, consisting of four plasmids, a phage, and numerous transposable elements, which may play a role in the dissemination of hmr and arsenic metabolism genes in the

Analysis of the Genome and Mobilome of a Dissimilatory Arsenate Reducing Aeromonas sp. O23A Reveals Multiple Mechanisms for Heavy Metal Resistance and Metabolism.

Science.gov (United States)

Uhrynowski, Witold; Decewicz, Przemyslaw; Dziewit, Lukasz; Radlinska, Monika; Krawczyk, Pawel S; Lipinski, Leszek; Adamska, Dorota; Drewniak, Lukasz

2017-01-01

Aeromonas spp. are among the most ubiquitous microorganisms, as they have been isolated from different environmental niches including waters, soil, as well as wounds and digestive tracts of poikilothermic animals and humans. Although much attention has been paid to the pathogenicity of Aeromonads, the role of these bacteria in environmentally important processes, such as transformation of heavy metals, remains to be discovered. Therefore, the aim of this study was a detailed genomic characterization of Aeromonas sp. O23A, the first representative of this genus capable of dissimilatory arsenate reduction. The strain was isolated from microbial mats from the Zloty Stok mine (SW Poland), an environment strongly contaminated with arsenic. Previous physiological studies indicated that O23A may be involved in both mobilization and immobilization of this metalloid in the environment. To discover the molecular basis of the mechanisms behind the observed abilities, the genome of O23A (∼5.0 Mbp) was sequenced and annotated, and genes for arsenic respiration, heavy metal resistance ( hmr ) and other phenotypic traits, including siderophore production, were identified. The functionality of the indicated gene modules was assessed in a series of minimal inhibitory concentration analyses for various metals and metalloids, as well as mineral dissolution experiments. Interestingly, comparative analyses revealed that O23A is related to a fish pathogen Aeromonas salmonicida subsp. salmonicida A449 which, however, does not carry genes for arsenic respiration. This indicates that the dissimilatory arsenate reduction ability may have been lost during genome reduction in pathogenic strains, or acquired through horizontal gene transfer. Therefore, particular emphasis was placed upon the mobilome of O23A, consisting of four plasmids, a phage, and numerous transposable elements, which may play a role in the dissemination of hmr and arsenic metabolism genes in the environment. The obtained

Analysis of the Genome and Mobilome of a Dissimilatory Arsenate Reducing Aeromonas sp. O23A Reveals Multiple Mechanisms for Heavy Metal Resistance and Metabolism

Science.gov (United States)

Uhrynowski, Witold; Decewicz, Przemyslaw; Dziewit, Lukasz; Radlinska, Monika; Krawczyk, Pawel S.; Lipinski, Leszek; Adamska, Dorota; Drewniak, Lukasz

2017-01-01

Aeromonas spp. are among the most ubiquitous microorganisms, as they have been isolated from different environmental niches including waters, soil, as well as wounds and digestive tracts of poikilothermic animals and humans. Although much attention has been paid to the pathogenicity of Aeromonads, the role of these bacteria in environmentally important processes, such as transformation of heavy metals, remains to be discovered. Therefore, the aim of this study was a detailed genomic characterization of Aeromonas sp. O23A, the first representative of this genus capable of dissimilatory arsenate reduction. The strain was isolated from microbial mats from the Zloty Stok mine (SW Poland), an environment strongly contaminated with arsenic. Previous physiological studies indicated that O23A may be involved in both mobilization and immobilization of this metalloid in the environment. To discover the molecular basis of the mechanisms behind the observed abilities, the genome of O23A (∼5.0 Mbp) was sequenced and annotated, and genes for arsenic respiration, heavy metal resistance (hmr) and other phenotypic traits, including siderophore production, were identified. The functionality of the indicated gene modules was assessed in a series of minimal inhibitory concentration analyses for various metals and metalloids, as well as mineral dissolution experiments. Interestingly, comparative analyses revealed that O23A is related to a fish pathogen Aeromonas salmonicida subsp. salmonicida A449 which, however, does not carry genes for arsenic respiration. This indicates that the dissimilatory arsenate reduction ability may have been lost during genome reduction in pathogenic strains, or acquired through horizontal gene transfer. Therefore, particular emphasis was placed upon the mobilome of O23A, consisting of four plasmids, a phage, and numerous transposable elements, which may play a role in the dissemination of hmr and arsenic metabolism genes in the environment. The obtained

Aquatically acquired Aeromonas hydrophila wound infection A ...

African Journals Online (AJOL)

The occurrence of Aeromonas hydrophila wound infections in healthy hosts after water-associated injury is being reported more frequently. This paper reports our experience with 3 such cases and outlines the importance of recognising the association between a water-related injury and, this organism.

Unusual microorganisms and antimicrobial resistances in a group of Syrian migrants: Sentinel surveillance data from an asylum seekers centre in Italy.

Science.gov (United States)

Angeletti, Silvia; Ceccarelli, Giancarlo; Vita, Serena; Dicuonzo, Giordano; Lopalco, Maurizio; Dedej, Etleva; Blasi, Aletheia; Antonelli, Francesca; Conti, Alessia; De Cesaris, Marina; Farchi, Francesca; Lo Presti, Alessandra; Ciccozzi, Massimo

2016-01-01

Three years of civil war in Syria have caused death and increase of communicable diseases. The suffering population has been forced to migrate creating a fertile condition for epidemic spread of infection within the refugee camps. Forty-eight Syrian migrants, upon their arrival in Italy, were accommodated at the asylum seekers centre of Castelnuovo di Porto. They received a physical examination and were subjected to microbiological surveillance by blood, rectal, pharyngeal and nasal swabs collection and delivering to the Clinical Pathology and Microbiology Laboratory of the University Campus Bio-Medico of Rome. All refugees resulted negative for HBV, HCV and HIV infections. In swabs a large number of unusual gram-negative bacteria species were isolated, such as Pseudomonas putida, Pseudomonas monteilii, Pseudomonas fulva, Pseudomonas moselii, Aeromonas veronii, Aeromonas caviae, Aeromonas hydrophila, Acinteobacter guilloviae, Acinteobacter lowffii; Acinetobacter johnsonii; Acinteobacter tjernbergae; Pantoea agglomerans; Pantoea calida. Among isolates, strains resistant to carbapenems, ESBL producers and methicillin resistant were found. The microbiological surveillance performed represents a useful action to understand refugees health status and to trace unusual microorganisms movement even carriers of antimicrobial resistance during migrants traveling. Copyright © 2016 Elsevier Ltd. All rights reserved.

Aeromonas spp. and microbial indicators in raw drinking water source Aeromonas sp. e indicadores microbiológicos em fontes de água não tratada

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Marisa Di Bari

2007-09-01

Full Text Available Aeromonas species are autochtonous in the aquatic environment and some of them have been associated with health effects like wound infections, septicemia and diarrhoeal illness. In this study, the occurrence of Aeromonas spp. and microbial indicators in raw drinking water from wells, springs, fountains and mineral waters was evaluated. A total of 126 water samples was analyzed for Aeromonas spp. by the membrane filtration technique using ADA media and by P/A test. Typical colonies of Aeromonas spp. were submitted to biochemical tests for species differentiation. Toxin production was tested using Y-1 mouse adrenal cells. Coliforms and heterotrophic bacteria were enumerated by membrane filtration and pour plate techniques, respectively. P. aeruginosa, C. perfringens and fecal streptococci were determined by P/A method. Aeromonas spp. were isolated in 36.5% of the samples, whereas total and thermotolerant coliforms were detected in 51.2% and in 23.8% of the samples, respectively. C. perfringens, fecal streptococci and P. aeruginosa were present in 16.5%, 20.4% and 3.8% of the samples, respectively. The concentrations of heterotrophic bacteria were higher than 1,0x10³ CFU/mL in 52.5% of the samples. A. hydrophila was the most frequent species, followed by A. allosaccharophila,A. jandaei,A.sobria and HG2. A heat label toxin was detected in 13 from the 58 strains tested. These data show that the drinking water sources analyzed can represent a risk for human health. It is important to consider that wells and springs are used as drinking water supply in poor areas and rural regions, where undernourished people more susceptible to infections by these microorganisms predominate.Bactérias do gênero Aeromonas são naturais no ambiente aquático e algumas espécies podem causar infecções em humanos como feridas, septicemia e diarréia. Este trabalho objetivou avaliar a ocorrência de Aeromonas sp. em 126 amostras de água de poços, nascentes, fontes e

Plasmid segregation mechanisms

DEFF Research Database (Denmark)

Ebersbach, G.; Gerdes, Kenn

2005-01-01

Bacterial plasmids encode partitioning (par) loci that ensure ordered plasmid segregation prior to cell division. par loci come in two types: those that encode actin-like ATPases and those that encode deviant Walker-type ATPases. ParM, the actin-like ATPase of plasmid R1, forms dynamic filaments...... that segregate plasmids paired at mid-cell to daughter cells. Like microtubules, ParM filaments exhibit dynamic instability (i.e., catastrophic decay) whose regulation is an important component of the DNA segregation process. The Walker box ParA ATPases are related to MinD and form highly dynamic, oscillating...... filaments that are required for the subcellular movement and positioning of plasmids. The role of the observed ATPase oscillation is not yet understood. However, we propose a simple model that couples plasmid segregation to ParA oscillation. The model is consistent with the observed movement...

Incidence of Aeromonas spp. infection in fish and chicken meat and its related public health hazards: A review

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Praveen Kumar Praveen

2016-01-01

Full Text Available Aeromonas is recognized to cause a variety of diseases in man. In humans, they are associated with intestinal and extraintestinal infections. With the growing importance of Aeromonas as an emerging pathogen, it is important to combat this organism. It is indisputable that Aeromonas strains may produce many different putative virulence factors such as enterotoxins, hemolysins or cytotoxins, and antibiotic resistance against different antibiotics. The ability of these bacteria to grow competitively at 5°C may be indicative of their potential as a public health hazard. Comprehensive enteric disease surveillance strategies, prevention and education are essential for meeting the challenges in the years ahead. It is important for us to promote the value of enteric cultures when patients have a gastrointestinal illness or bloody diarrhea or when multiple cases of enteric disease occur after a common exposure. With the growing importance of Aeromonas as an emerging pathogen, it is important to combat this organism. It is indisputable that Aeromonas strains may produce many different putative virulence factors, such as enterotoxins, hemolysins or cytotoxins. It has been established that aerolysin is a virulence factor contributing to the pathogenesis of Aeromonas hydrophila infection. Fish and chicken play an important role in the transmission of this pathogen to humans. In the present study, the high prevalence of toxin-producing strains was found among the Aeromonas isolates. The ability of these bacteria to grow competitively at 5°C may be indicative of their potential as a public health hazard. The present review was constructed with a view to highlight the zoonotic importance of Aeromonas pathogen in fish and chicken meat.

Incidence of Aeromonas spp. infection in fish and chicken meat and its related public health hazards: A review.

Science.gov (United States)

Praveen, Praveen Kumar; Debnath, Chanchal; Shekhar, Shashank; Dalai, Nirupama; Ganguly, Subha

2016-01-01

Aeromonas is recognized to cause a variety of diseases in man. In humans, they are associated with intestinal and extra-intestinal infections. With the growing importance of Aeromonas as an emerging pathogen, it is important to combat this organism. It is indisputable that Aeromonas strains may produce many different putative virulence factors such as enterotoxins, hemolysins or cytotoxins, and antibiotic resistance against different antibiotics. The ability of these bacteria to grow competitively at 5°C may be indicative of their potential as a public health hazard. Comprehensive enteric disease surveillance strategies, prevention and education are essential for meeting the challenges in the years ahead. It is important for us to promote the value of enteric cultures when patients have a gastrointestinal illness or bloody diarrhea or when multiple cases of enteric disease occur after a common exposure. With the growing importance of Aeromonas as an emerging pathogen, it is important to combat this organism. It is indisputable that Aeromonas strains may produce many different putative virulence factors, such as enterotoxins, hemolysins or cytotoxins. It has been established that aerolysin is a virulence factor contributing to the pathogenesis of Aeromonas hydrophila infection. Fish and chicken play an important role in the transmission of this pathogen to humans. In the present study, the high prevalence of toxin-producing strains was found among the Aeromonas isolates. The ability of these bacteria to grow competitively at 5°C may be indicative of their potential as a public health hazard. The present review was constructed with a view to highlight the zoonotic importance of Aeromonas pathogen in fish and chicken meat.

Antimicrobial susceptibility pattern of Aeromonas hydrophila among ...

African Journals Online (AJOL)

A total of one hundred and twenty eight (128) stool samples were collected from patients attending Ahmadu Bello University Teaching Hospital Zaria and Aminu Kano Teaching Hospital Kano, and screened for the presence of Aeromonas hydrophila infection. Out of the one hundred and twenty eight samples analyzed 4 ...

Detection of Aeromonas hydrophila Using Fiber Optic Microchannel Sensor

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Samla Gauri

2017-01-01

Full Text Available This research focuses on the detection of Aeromonas hydrophila using fiber optic microchannel biosensor. Microchannel was fabricated by photolithography method. The fiber optic was chosen as signal transmitting medium and light absorption characteristic of different microorganisms was investigated for possible detection. Experimental results showed that Aeromonas hydrophila can be detected at the region of UV-Vis spectra between 352 nm and 354 nm which was comparable to measurement provided by UV spectrophotometer and also theoretical calculation by Beer-Lambert Absorption Law. The entire detection can be done in less than 10 minutes using a total volume of 3 μL only. This result promises good potential of this fiber optic microchannel sensor as a reliable, portable, and disposable sensor.

Classification of a hypervirulent Aeromonas hydrophila pathotype responsible for epidemic outbreaks in warm-water fishes

Science.gov (United States)

Lineages of hypervirulent Aeromonas hydrophila (vAh) are the cause of persistent outbreaks of motile Aeromonas septicemia in warm-water fishes worldwide. Over the last decade, this virulent lineage of A. hydrophila has resulted in annual losses of millions of tons of farmed carp and catfish in the P...

Characterization of atypical Aeromonas salmonicida by different methods

DEFF Research Database (Denmark)

Austin, B.; Austin, D.A.; Dalsgaard, Inger

1998-01-01

Fifty two isolates of atypical Aeromonas salmonicida, recovered from a wide range of hosts and geographical locations, were heterogeneous in terms of molecular and phenotypic characteristics, and represented taxa which could not be accommodated by the current classification of four subspecies...

Pathogenic potentials of Aeromonas species isolated from aquaculture and abattoir environments.

Science.gov (United States)

Igbinosa, Isoken H; Beshiru, Abeni; Odjadjare, Emmanuel E; Ateba, Collins N; Igbinosa, Etinosa O

2017-06-01

The present study elucidated the presence of antibiotics resistance, virulence genes and biofilm potentials among Aeromonas species isolated from abattoir and aquaculture environments in Benin City, Nigeria. A total of 144 wastewater samples were obtained from two independent aquaculture and abattoir environments between May and October 2016. Aeromonas species were isolated on Glutamate Starch Phenol Red (GSP) agar and confirmed using API 20NE kits. Antimicrobial susceptibility profile of the isolates was carried out using standard disc diffusion assay while biofilm potentials were detected by the microtitre plate method and PCR technique was used to detect antibiotics resistance and virulence gene markers. Overall, 32 and 26 Aeromonas species were isolated from the abattoir and aquaculture environments respectively. Isolates from both environments were completely resistant (100%) to penicillin G, ertapenem and tetracycline; whereas aquaculture isolates exhibited absolute sensitivity (100%) towards cefepime. All the virulence gene markers (aerA, hlyA, alt, ast, laf, ascF-G, fla, lip, stx1, and stx2) investigated in this study (except laf) were detected in isolates from both environments. The laf genes were only detected in isolates from abattoir environments. Antibiotics resistant genes including pse, bla TEM and class 1 integron were detected in isolates from both environments. Majority of the isolates (53/58 91.4%) from both environments; demonstrated capacity for biofilm potential. The detection of antibiotic resistance and virulence gene markers as well as biofilm forming ability in Aeromonas species isolated from aquaculture and abattoir environments raise serious public health concern worthy of further investigation. Copyright © 2017 Elsevier Ltd. All rights reserved.

Polymerase chain reaction (PCR)-based typing analysis of atypical isolates of the fish pathogen Aeromonas salmonicida

DEFF Research Database (Denmark)

Høie, S.; Dalsgaard, Inger; Aase, I.L.

1999-01-01

. salmonicida subsp. salmonicida isolates tested, belonged to group 1. The PCR primer-sets separated A. salmonicida from other reference strains of Aeromonas species and related bacteria with the exception of Aeromonas hydrophila. The results indicated that PCR typing is a useful framework for characterization...

Presence of Aeromonas spp in water from drinking-water- and wastewater-treatment plants in Mexico City.

Science.gov (United States)

Villarruel-López, Angélica; Fernández-Rendón, Elizabeth; Mota-de-la-Garza, Lydia; Ortigoza-Ferado, Jorge

2005-01-01

The frequency of Aeromonas spp in three wastewater-treatment plants (WWTPs) and two drinking-water plants (DWPs) in México City was determined. Samples were taken throughout a year by the Moore's swab technique. A total of 144 samples were obtained from WWTPs and 96 from DWPs of both incoming and outflowing water. Aeromonas spp was isolated in 31% of the samples, from both kinds of sources. The technique used for the isolation of the pathogen was suitable for samples with high associate microbiota content and for those with a scarce microbial content. The presence of mesophilic-aerobic, coliform, and fecal-coliform organisms was investigated to determine whether there was any correlation with the presence of Aeromonas spp. Most samples from WWTP, which did not comply with the Mexican standards, had the pathogen, and some of the samples from the outflow of the DWP, which were within the limits set by the Mexican standards, also had Aeromonas spp. Most samples containing Aeromonas spp. had concentrations below 0.1 ppm residual chlorine, and the strains were resistant to 0.3 ppm, which supports the recommendation to increase the residual chlorine concentration to 0.5 to 1.0 ppm, as recommended by the Mexican standards.

Aeromonas Bacteraemia Causing Gas Gangrene in a Diabetic ...

African Journals Online (AJOL)

Early blood culture, culture of the aspirates from blebs, and subsequent culture of intraoperative specimens uniformly grew Aeromonas hydrophila. Urgent fasciotomy was carried out same day, and the patient was admitted into ICU for intensive monitoring and therapies. Second look procedures 48hours later showed turgid ...

Comparative symbiotic plasmid analysis indicates that symbiosis gene ancestor type affects plasmid genetic evolution.

Science.gov (United States)

Wang, X; Zhao, L; Zhang, L; Wu, Y; Chou, M; Wei, G

2018-07-01

Rhizobial symbiotic plasmids play vital roles in mutualistic symbiosis with legume plants by executing the functions of nodulation and nitrogen fixation. To explore the gene composition and genetic constitution of rhizobial symbiotic plasmids, comparison analyses of 24 rhizobial symbiotic plasmids derived from four rhizobial genera was carried out. Results illustrated that rhizobial symbiotic plasmids had higher proportion of functional genes participating in amino acid transport and metabolism, replication; recombination and repair; carbohydrate transport and metabolism; energy production and conversion and transcription. Mesorhizobium amorphae CCNWGS0123 symbiotic plasmid - pM0123d had similar gene composition with pR899b and pSNGR234a. All symbiotic plasmids shared 13 orthologous genes, including five nod and eight nif/fix genes which participate in the rhizobia-legume symbiosis process. These plasmids contained nod genes from four ancestors and fix genes from six ancestors. The ancestral type of pM0123d nod genes was similar with that of Rhizobium etli plasmids, while the ancestral type of pM0123d fix genes was same as that of pM7653Rb. The phylogenetic trees constructed based on nodCIJ and fixABC displayed different topological structures mainly due to nodCIJ and fixABC ancestral type discordance. The study presents valuable insights into mosaic structures and the evolution of rhizobial symbiotic plasmids. This study compared 24 rhizobial symbiotic plasmids that included four genera and 11 species, illuminating the functional gene composition and symbiosis gene ancestor types of symbiotic plasmids from higher taxonomy. It provides valuable insights into mosaic structures and the evolution of symbiotic plasmids. © 2018 The Society for Applied Microbiology.

Plasmid flux in Escherichia coli ST131 sublineages, analyzed by plasmid constellation network (PLACNET), a new method for plasmid reconstruction from whole genome sequences.

Science.gov (United States)

Lanza, Val F; de Toro, María; Garcillán-Barcia, M Pilar; Mora, Azucena; Blanco, Jorge; Coque, Teresa M; de la Cruz, Fernando

2014-12-01

Bacterial whole genome sequence (WGS) methods are rapidly overtaking classical sequence analysis. Many bacterial sequencing projects focus on mobilome changes, since macroevolutionary events, such as the acquisition or loss of mobile genetic elements, mainly plasmids, play essential roles in adaptive evolution. Existing WGS analysis protocols do not assort contigs between plasmids and the main chromosome, thus hampering full analysis of plasmid sequences. We developed a method (called plasmid constellation networks or PLACNET) that identifies, visualizes and analyzes plasmids in WGS projects by creating a network of contig interactions, thus allowing comprehensive plasmid analysis within WGS datasets. The workflow of the method is based on three types of data: assembly information (including scaffold links and coverage), comparison to reference sequences and plasmid-diagnostic sequence features. The resulting network is pruned by expert analysis, to eliminate confounding data, and implemented in a Cytoscape-based graphic representation. To demonstrate PLACNET sensitivity and efficacy, the plasmidome of the Escherichia coli lineage ST131 was analyzed. ST131 is a globally spread clonal group of extraintestinal pathogenic E. coli (ExPEC), comprising different sublineages with ability to acquire and spread antibiotic resistance and virulence genes via plasmids. Results show that plasmids flux in the evolution of this lineage, which is wide open for plasmid exchange. MOBF12/IncF plasmids were pervasive, adding just by themselves more than 350 protein families to the ST131 pangenome. Nearly 50% of the most frequent γ-proteobacterial plasmid groups were found to be present in our limited sample of ten analyzed ST131 genomes, which represent the main ST131 sublineages.

[Replication of Streptomyces plasmids: the DNA nucleotide sequence of plasmid pSB 24.2].

Science.gov (United States)

Bolotin, A P; Sorokin, A V; Aleksandrov, N N; Danilenko, V N; Kozlov, Iu I

1985-11-01

The nucleotide sequence of DNA in plasmid pSB 24.2, a natural deletion derivative of plasmid pSB 24.1 isolated from S. cyanogenus was studied. The plasmid amounted by its size to 3706 nucleotide pairs. The G-C composition was equal to 73 per cent. The analysis of the DNA structure in plasmid pSB 24.2 revealed the protein-encoding sequence of DNA, the continuity of which was significant for replication of the plasmid containing more than 1300 nucleotide pairs. The analysis also revealed two A-T-rich areas of DNA, the G-C composition of which was less than 55 per cent and a DNA area with a branched pin structure. The results may be of value in investigation of plasmid replication in actinomycetes and experimental cloning of DNA with this plasmid as a vector.

Aeromonas hydrophila disturbs water and electrolyte transport in ...

African Journals Online (AJOL)

SERVER

2008-02-19

Feb 19, 2008 ... enterocytes with voluminous and spherical shape, disappearance of enterocyte brush border and lesions at ... (Paniagua et al., 1990) and causes different diseases. ... 22°C and the fish were fed on a standard diet composed of algae. ..... J (1998). Aeromonas hydrophila causes 'black diseases' in fairy.

Population dynamics, antibiotics resistance and biofilm formation of Aeromonas and Vibrio species isolated from aquatic sources in Northern Malaysia.

Science.gov (United States)

Odeyemi, Olumide A; Ahmad, Asmat

2017-02-01

This study aimed to compare population dynamics, antibiotic resistance and biofilm formation of Aeromonas and Vibrio species from seawater and sediment collected from Northern Malaysia. Isolates with different colony morphology were characterized using both biochemical and molecular methods before testing for antibiotic resistance and biofilm formation. Results obtained from this study showed that in Kedah, the population of Aeromonas isolated from sediment was highest in Pantai Merdeka (8.22 log CFU/ml), Pulau Bunting recorded the highest population of Aeromonas from sediment (8.43 log CFU/g). It was observed that Vibrio species isolated from seawater and sediment were highest in Kuala Sanglang (9.21 log CFU/ml). In Kuala Perlis, the population of Aeromonas isolated from seawater was highest in Jeti (7.94 log CFU/ml). Highest population of Aeromonas from sediment was recorded in Kampong Tanah Baru (7.99 log CFU/g). It was observed that Vibrio species isolated from seawater was highest in Padang Benta (8.42 log CFU/g) while Jeti Kuala Perlis had highest population of Vibrio isolated from sediment. It was observed that location does not influence population of Aeromonas. The results of the independent t - test revealed that there was no significant relationship between location and population of Vibrio (df = 10, t = 1.144, p > 0.05). The occurrence of biofilm formation and prevalence of antibiotic resistant Aeromonas and Vibrio species in seawater and sediment pose danger to human and aquatic animals' health. Copyright © 2017 Elsevier Ltd. All rights reserved.

CONTAMINATION RISK ASSESSMENT OF SOURCES OF WATER INTENDED FOR HUMAN CONSUMPTION WITH AEROMONAS SPP.

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Luminita Minea

2012-03-01

Full Text Available mportance of Aeromonas spp as emerging pathogens in recent years has been a considerable increase, beingincluded by the World Health Organization (WHO and Environmental Protection Agency (EPA in the etiology ofwaterborne epidemics. We aimed to investigate the distribution of Aeromonas spp. in various aquatic ecosystems whichcan become potential sources of gastrointestinal infections. Simultaneously, the presence of this pathogen was evaluatedin relation to microbiological indicators set out in EU Directive 98/83/EC. Between March 2009 and May 2011 wereanalyzed by membrane filter technique untreated water samples, collected from surface sources (lakes, ponds andgroundwater (wells drilled, captured springs, wells and chlorinated water that coming from local distribution network,located in rural areas of Moldova (North-East Romania. The information was processed and interpreted statisticallyusing EpiInfo 3.5.1 software. The presence of Aeromonas spp. was detected in half of the 220 samples tested, especially,in surface waters (84% and captured springs (80.8% (χ 2=51.39; GL=4; p0.8, being influenced by exogenous humanimpact. The results of this study confirms that untreated water used in rural areas can affect public health andmicrobiological indicators have predictive value for the presence of Aeromonas spp only reporting to surface sources.

Plasmid Flux in Escherichia coli ST131 Sublineages, Analyzed by Plasmid Constellation Network (PLACNET), a New Method for Plasmid Reconstruction from Whole Genome Sequences

Science.gov (United States)

Garcillán-Barcia, M. Pilar; Mora, Azucena; Blanco, Jorge; Coque, Teresa M.; de la Cruz, Fernando

2014-01-01

Bacterial whole genome sequence (WGS) methods are rapidly overtaking classical sequence analysis. Many bacterial sequencing projects focus on mobilome changes, since macroevolutionary events, such as the acquisition or loss of mobile genetic elements, mainly plasmids, play essential roles in adaptive evolution. Existing WGS analysis protocols do not assort contigs between plasmids and the main chromosome, thus hampering full analysis of plasmid sequences. We developed a method (called plasmid constellation networks or PLACNET) that identifies, visualizes and analyzes plasmids in WGS projects by creating a network of contig interactions, thus allowing comprehensive plasmid analysis within WGS datasets. The workflow of the method is based on three types of data: assembly information (including scaffold links and coverage), comparison to reference sequences and plasmid-diagnostic sequence features. The resulting network is pruned by expert analysis, to eliminate confounding data, and implemented in a Cytoscape-based graphic representation. To demonstrate PLACNET sensitivity and efficacy, the plasmidome of the Escherichia coli lineage ST131 was analyzed. ST131 is a globally spread clonal group of extraintestinal pathogenic E. coli (ExPEC), comprising different sublineages with ability to acquire and spread antibiotic resistance and virulence genes via plasmids. Results show that plasmids flux in the evolution of this lineage, which is wide open for plasmid exchange. MOBF12/IncF plasmids were pervasive, adding just by themselves more than 350 protein families to the ST131 pangenome. Nearly 50% of the most frequent γ–proteobacterial plasmid groups were found to be present in our limited sample of ten analyzed ST131 genomes, which represent the main ST131 sublineages. PMID:25522143

Plasmid flux in Escherichia coli ST131 sublineages, analyzed by plasmid constellation network (PLACNET, a new method for plasmid reconstruction from whole genome sequences.

Directory of Open Access Journals (Sweden)

Val F Lanza

2014-12-01

Full Text Available Bacterial whole genome sequence (WGS methods are rapidly overtaking classical sequence analysis. Many bacterial sequencing projects focus on mobilome changes, since macroevolutionary events, such as the acquisition or loss of mobile genetic elements, mainly plasmids, play essential roles in adaptive evolution. Existing WGS analysis protocols do not assort contigs between plasmids and the main chromosome, thus hampering full analysis of plasmid sequences. We developed a method (called plasmid constellation networks or PLACNET that identifies, visualizes and analyzes plasmids in WGS projects by creating a network of contig interactions, thus allowing comprehensive plasmid analysis within WGS datasets. The workflow of the method is based on three types of data: assembly information (including scaffold links and coverage, comparison to reference sequences and plasmid-diagnostic sequence features. The resulting network is pruned by expert analysis, to eliminate confounding data, and implemented in a Cytoscape-based graphic representation. To demonstrate PLACNET sensitivity and efficacy, the plasmidome of the Escherichia coli lineage ST131 was analyzed. ST131 is a globally spread clonal group of extraintestinal pathogenic E. coli (ExPEC, comprising different sublineages with ability to acquire and spread antibiotic resistance and virulence genes via plasmids. Results show that plasmids flux in the evolution of this lineage, which is wide open for plasmid exchange. MOBF12/IncF plasmids were pervasive, adding just by themselves more than 350 protein families to the ST131 pangenome. Nearly 50% of the most frequent γ-proteobacterial plasmid groups were found to be present in our limited sample of ten analyzed ST131 genomes, which represent the main ST131 sublineages.

Pathogenic bacteria in sewage treatment plants as revealed by 454 pyrosequencing.

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Ye, Lin; Zhang, Tong

2011-09-01

This study applied 454 high-throughput pyrosequencing to analyze potentially pathogenic bacteria in activated sludge from 14 municipal wastewater treatment plants (WWTPs) across four countries (China, U.S., Canada, and Singapore), plus the influent and effluent of one of the 14 WWTPs. A total of 370,870 16S rRNA gene sequences with average length of 207 bps were obtained and all of them were assigned to corresponding taxonomic ranks by using RDP classifier and MEGAN. It was found that the most abundant potentially pathogenic bacteria in the WWTPs were affiliated with the genera of Aeromonas and Clostridium. Aeromonas veronii, Aeromonas hydrophila, and Clostridium perfringens were species most similar to the potentially pathogenic bacteria found in this study. Some sequences highly similar (>99%) to Corynebacterium diphtheriae were found in the influent and activated sludge samples from a saline WWTP. Overall, the percentage of the sequences closely related (>99%) to known pathogenic bacteria sequences was about 0.16% of the total sequences. Additionally, a platform-independent Java application (BAND) was developed for graphical visualization of the data of microbial abundance generated by high-throughput pyrosequencing. The approach demonstrated in this study could examine most of the potentially pathogenic bacteria simultaneously instead of one-by-one detection by other methods.

Simultaneous effects of environmental factors on motile Aeromonas dynamics in an urban effluent and in the natural seawater.

Science.gov (United States)

Maalej, Sami; Mahjoubi, Amira; Elazri, Chafai; Dukan, Sam

2003-07-01

Seasonal dynamics of motile Aeromonas in a treated urban effluent and in natural seawater along the Sfax coast (Mediterranean sea, Tunisia) were measured over a year concurrently with seven environmental factors, and compared with those of faecal coliforms. Counts for Aeromonas from a standard plate count method, ranged from 1.48 x 10(5)CFU.100 ml(-1) to 2.2 x 10(8)CFU.100 ml(-1) in the effluent and from 7.9 x 10(3)CFU.100 ml(-1) to undetectable level in the surface marine waters. Contrary to faecal coliforms, the Aeromonas dynamics exhibited a seasonal distribution in seawater which was inverse of the seasonal distribution in the sewage: From the end of November 1998 to April 1999 (cold period), Aeromonas counts increased in the treated effluent, while it decreased very rapidly in seawater. From May to October (warm period), Aeromonas abundance decreased in the effluent but showed an increasing fluctuating trend in the marine waters with a maximum in late summer/early autumn when the temperatures were around 22-23 degrees C. Multiple correlation and regression analyses suggest, by the coefficient of determination (R(2)), that 42% of variance in Aeromonas number changes in the treated effluent, may be explained by only turbidity, radiation and Aeromonas density in the previous sample, while 37% of variance in marine ecosystem were explained by radiance and conductivity. Furthermore, the t statistics and their p values and the coefficient of partial determination (r(2)) indicated that radiance contributed the most (r(2)=0.3184, t=-3.2, p=0.0041) to the dynamics of motile Aeromonas in seawater, when combined with conductivity. The models relevant for changes in faecal coliforms abundance incorporated turbidity, radiance in the effluent and conductivity, pH, radiance, turbidity in coastal marine environment. These models explain 66% and 73% of the observed cell number fluctuation, with turbidity (r(2)=0.529, t=5.08, p=0.0001) and conductivity (r(2)=0.5407, t=4.97, p=0

Aeromonas hydrophila disturbs water and electrolyte transport in ...

African Journals Online (AJOL)

Fish diseases create a menace to aquaculture farms. They provoke disastrous economic losses and sanitary risks for the consumer. The present study aims to investigate the effect of the bacteria, Aeromonas hydrophila on water and electrolyte (Na+, K+, Cl-, HCO3 -) flux of Mugil cephalus (L, 1758) intestine. Anterior, middle ...

The Effect of Some Physical and Chemical Parameters on Regrowth of Aeromonas Bacterium and Heterotrophic Bacteria in Isfahan Drinking Water System

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Sina Dobaradaran

2006-03-01

Full Text Available Aeromonas is one the gram – negative , non spor – formating rod shaping , facultatively anaerobic and opportunistic bactria that can cause systematic infections, leision and diarrhoea in human. Fairly high bactrial population in distribution system is not only of concern because of affecting consumer health but also it makes it difficult to enumerate coliform bacterium indicator. So, the relationships between aeromonas and heterotrophic bacteria growth with pH, temperature, turbidity, free residual cholornie and DO were determined in this study. ADA- V media was used in presumptive stage to count aeromonas bacteria for the first time in Iran on the basis of 1605 EPA (2001 method and used oxidase tests, trehalose fermentation and indol test in confirmative stage. R2A media was used to count HPC bacteria and other factors measured on the basis of standards. The results showed that positive cases of aeromonas bacteria and HPC increase in higher temperature and turbidity and lower pH. In contrast, positive cases of aeromonas bacteria and HPC decrease while free residual cholorine and DO increase. In addition,no positive case of aeromonas was observed in more than 0.2 mg/L concentration of free residual cholorine.

Aeromonas spp. in het Nederlandse drinkwater; een orienterend onderzoek

NARCIS (Netherlands)

Versteegh JFM; During M; Havelaar AH; Koot W

1986-01-01

In dit rapport worden uitvoering en resultaten van een orienterend onderzoek naar het voorkomen van Aeromonas spp. in het Nederlandse drinkwater in 1985 besproken. Het bleek dat in 71% van de onderzochte monsters (rein water "af pompstation" en water uit het distributienet) in 100 ml

Ciprofloxacin-Resistant Aeromonas hydrophila Cellulitis following Leech Therapy

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Giltner, Carmen L.; Bobenchik, April M.; Uslan, Daniel Z.; Deville, Jaime G.

2013-01-01

We report a case of surgical site infection with ciprofloxacin-resistant Aeromonas hydrophila following leech therapy. Antimicrobial and genetic analyses of leech and patient isolates demonstrated that the resistant isolates originated from the leech gut microbiota. These data suggest that ciprofloxacin monotherapy as a prophylaxis regimen prior to leech therapy may not be effective in preventing infection. PMID:23363826

Occurrence of potential pathogenic Aeromonas species in tropical seafood, aquafarms and mangroves off Cochin coast in South India

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Alphonsa Vijaya Joseph

2013-12-01

Full Text Available Background: The genus Aeromonas include gram-negative, motile, facultative anaerobic, rod shaped and oxidase positive bacteria comprising several species, associated with the aquatic environment. Aeromonas species have been implicated in human pathogenesis and are linked with gastroenteritis, muscle infections, septicemia, and skin diseases. In fish they are renowned as enteric pathogens causing haemorrhagic septicemia, fin rot, soft tissue rot and furunculosis resulting in major die-offs and fish kills. Aim: This study reports the occurrence of potential pathogenic Aeromonas sp. in tropical seafood (Squids, Prawns and Mussels, aquafarms and mangroves of Cochin, Kerala, South India. Materials and Methods :Tropical seafood (Squid, Prawn and Mussel, sediment and water samples from aquafarms and associated mangroves were screened for Aeromonas contamination. The isolates were identified by 16S rDNA sequence analysis and subjected to morphological and biochemical characterization. Haemolytic assay was used for determining pathogenicity of the organisms. Antibiotic susceptibility against 12 antibiotics were performed and the MAR index was calculated. Results: A total of 134 isolates were recovered from the samples of which 15 were identified as Aeromonas species by 16S rDNA sequence analysis and were assigned to 5 species namely, A. hydrophila, A. enteropelogenes, A. caviae, A. punctataand A. aquarorium. Morphological, biochemical and phylogenetic analyses revealed relatedness and variability among the strains. All the isolates were haemolytic on blood agar indicating their pathogenicity. The isolates exhibited varying degrees of resistance to vancomycin (86.66%, ampicillin (46.66%, nalidixic acid (20%, tetracycline (6.66%, co-trimaxozole (6.66% and rifampicin (6.66% and were susceptible to antibiotics like gentamycin, streptomycin, trimethoprim, azithromycin, cefixime and chloramphenicol. 20% of Aeromonas sp. showed MAR index > 0.2 indicative of the

Origin and Evolution of Rickettsial Plasmids.

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Khalid El Karkouri

Full Text Available Rickettsia species are strictly intracellular bacteria that have undergone a reductive genomic evolution. Despite their allopatric lifestyle, almost half of the 26 currently validated Rickettsia species have plasmids. In order to study the origin, evolutionary history and putative roles of rickettsial plasmids, we investigated the evolutionary processes that have shaped 20 plasmids belonging to 11 species, using comparative genomics and phylogenetic analysis between rickettsial, microbial and non-microbial genomes.Plasmids were differentially present among Rickettsia species. The 11 species had 1 to 4 plasmid (s with a size ranging from 12 kb to 83 kb. We reconstructed pRICO, the last common ancestor of the current rickettsial plasmids. pRICO was vertically inherited mainly from Rickettsia/Orientia chromosomes and diverged vertically into a single or multiple plasmid(s in each species. These plasmids also underwent a reductive evolution by progressive gene loss, similar to that observed in rickettsial chromosomes, possibly leading to cryptic plasmids or complete plasmid loss. Moreover, rickettsial plasmids exhibited ORFans, recent gene duplications and evidence of horizontal gene transfer events with rickettsial and non-rickettsial genomes mainly from the α/γ-proteobacteria lineages. Genes related to maintenance and plasticity of plasmids, and to adaptation and resistance to stress mostly evolved under vertical and/or horizontal processes. Those involved in nucleotide/carbohydrate transport and metabolism were under the influence of vertical evolution only, whereas genes involved in cell wall/membrane/envelope biogenesis, cycle control, amino acid/lipid/coenzyme and secondary metabolites biosynthesis, transport and metabolism underwent mainly horizontal transfer events.Rickettsial plasmids had a complex evolution, starting with a vertical inheritance followed by a reductive evolution associated with increased complexity via horizontal gene

The occurrence of Aeromonas spp. in the bottled mineral water, well water and tap water from the municipal supplies

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Denise de Oliveira Scoaris

2008-10-01

Full Text Available The aim of this work was to study the occurrence of Aeromonas sp in the bottled mineral water, well water and tap water from the municipal supplies. Positive samples were found for Aeromonas spp. 12.7% from the mineral water, 8.3% from the artesian water and 6.5% from the tap water. The recovery of Aeromonas spp. was significantly higher in the bottled mineral and artesian water than in the tap water from municipal supplies. The occurrence of the Aeromonas spp. did not correlate significantly with the contamination indicator bacteria (i.e. total coliforms in the artesian water samples. However, a significant correlation was found between Aeromonas spp. and total coliforms in the both mineral water and tap water samples. The presence or absence of a correlation between the indicator bacteria and Aeromonas could reflect the occasional appearance of the pathogen in the drinking water and the different rates of survival and recovery of these agents compared with those fecal indicators. The finding that 41.6, 14.8 and 9.0 % of the artesian water, bottled mineral water and tap water, respectively, sampled in the current study failed to meet the Brazilian standard for total coliforms in the drinking water should therefore be of concern.A porcentagem de amostras positivas para Aeromonas foi de 12.7% para água mineral, 8.3% para água de poço artesiano e 6.5% para água do sistema público de abastecimento. O isolamento de Aeromonas spp. foi significativamente maior em água mineral e água de poço artesiano do que em água do sistema público. A ocorrência de Aeromonas spp. não teve correlação significativa com os indicadores de contaminação tradicionalmente utilizados (coliformes totais em amostras de água de poço artesiano. No entanto, esta correlação foi positiva e significativa em água mineral e água do sistema público. A presença ou ausência de correlação entre bactérias indicadoras e a presença de Aeromonas pode refletir o

İnek Sütlerinin Hareketli Aeromonas Türleri Yönünden İncelenmesi

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Mustafa Alişarlı

2015-02-01

Full Text Available Bu çalışmada, çiğ sütlerde hareketli Aermonas türlerinin bulunma sıklığını ortaya koymak ve ilk sağılan sütün kontaminasyondaki rolünü belirlemek amaçlanmaştır. Bu amaçla, 100 adet sağmal inekten direkt el sağımı ile alınan süt örnekleri incelenmiştir. İncelenen Örneklerin 8 tanesinde (%8 Aeromonas spp.izole edilmiş olup bunlardan 3'ü (%37,5 hareketli Aeromonas olarak belirlenmiştir. Hareketli Aeromonas'ların 2'si (%66,6 A. hydrophila ve1'i (%33,3 A. caviae olarak identifiye edilmiştir. Bu araştırmanın verileri, süt işletmelerine tanker ve güğümlerle getirilen çiğ sütlerden sağlanan örneklerdeki araştırma bulgularıyla kıyaslandığında daha düşük bulunmuştur. Bu da, eğer sağım sonrası hijyen kurallarına gerekli özen gösterilmezse çiğ sütlerin Aeromonas'lar ile kontaminasyon riskinin yüksek olacağını göstermektedir.

In vitro comparisons of the inhibitory activity of florfenicol copper sulfate and potassium permanganate towards Aeromonas hydrophila and Flavobacterium columnare

Science.gov (United States)

Aeromonas hydrophila and Flavobacterium columnare, the etiological agents of motile aeromonas septicemia (MAS) and columnaris disease, respectively, have been recently causing crippling moralities to the sunshine bass, Morone chrysops female X Morone saxatilis male (Percichthyidae), industry in the ...

Immunological evaluation of Aeromonas infection in albino rats | El ...

African Journals Online (AJOL)

Aeromonas hydrophila is the most common bacterial species causing an acute self limiting diarrheal illness in mammals. Albino rats were categorized into treated and control groups. Treated groups were injected daily intraperitoneally with 0.2ml of bacterial suspension containing 6x106 cells/ml of 0.9% NaCl, while the ...

Yeast transformation mediated by Agrobacterium strains harboring an Ri plasmid: comparative study between GALLS of an Ri plasmid and virE of a Ti plasmid.

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Kiyokawa, Kazuya; Yamamoto, Shinji; Sato, Yukari; Momota, Naoto; Tanaka, Katsuyuki; Moriguchi, Kazuki; Suzuki, Katsunori

2012-07-01

Agrobacterium strains containing a Ti plasmid can transfer T-DNA not only to plants but also to fungi, including the yeast Saccharomyces cerevisiae. However, no Agrobacterium strain harboring an Ri plasmid has been evaluated in fungal transformation. Some Ri plasmids have GALLS , instead of virE1 and virE2. GALLS protein can functionally substitute in plant transformation for a structurally different protein VirE2. In this study, we compared the yeast transformation ability among Agrobacterium donors: a strain containing a Ti plasmid, strains harboring either an agropine-type or a mikimopine-type Ri plasmid, and a strain having a modified Ri plasmid supplemented with a Ti plasmid type virE operon. Agrobacterium strains possessing GALLS transformed yeast cells far less efficiently than the strain containing virE operon. Production of GALLS in recipient yeast cells improved the yeast transformation mediated by an Agrobacterium strain lacking neither GALLS nor virE operon. A reporter assay to detect mobilization of the proteins fused with Cre recombinase revealed that VirE2 protein is much more abundant in yeast cells than GALLS. Based on these results, we concluded that the low yeast transformability mediated by Agrobacterium strains having the Ri plasmid is because of low amount of mobilized GALLS in yeast cells. © 2012 The Authors Journal compilation © 2012 by the Molecular Biology Society of Japan/Blackwell Publishing Ltd.

Potential of Chromolaena odorata Leaf as A Cure of Aeromonas hydrophila on Giant Gouramy (Osphronemus gouramy

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Y. Hadiroseyani

2007-07-01

Full Text Available This study was conducted to examine the potency of Chromolaena odorata leaf extract as a medicine for skin eruption disease caused by  Aeromonas hydrophila in giant gouramy Osphronemus gouramy.  Leaf extract of Chromolaena odorata for in vitro test was 0 (as control, 13000, 15000, 17000, 19000 and 21000 ppm, poured onto TSA medium containing bacteria 103 cfu/ml, and then is incubated for 24 hours. In vivo test was performed by injecting bacteria 0.1 ml of 109 cfu/ml intramuscularly into giant gouramy (14 g weight, and then  fish were maintained in the water containing 15000 ppm of Chromolaena odorata leaf extract. In vitro study showed that prevention area of leaf extract against Aeromonas hydrophila was increase by increasing the concentration of leaf extract used, reached 9,33 mm.  Prevention zone of leaf extract by difusion tends to constant, reached 7,6 mm. By in vivo test, survival rate of giant gouramy infected by Aeromonas hydrophila was no significantly different between dosages of leaf extract.  All treated fish, excluded control died after 24 hours infection. Keywords: Aeromonas hydrophila, Osphronemus gouramy, Chromolaena odorata   ABSTRAK Penelitian ini dilakukan untuk mengetahui potensi daun kirinyuh Chromolaena odorata sebagai obat untuk penyakit cacar yang diakibatkan oleh Aeromonas hydrophila pada ikan gurame Osphronemus gouramy. Konsentrasi ekstrak daun Chromolaena odorata untuk uji in vitro adalah 13000, 15000, 17000, 19000 dan 21000 serta 0 ppm sebagai kontrol, yang diletakkan di atas media TSA yang telah mengandung biakan bakteri 103 cfu/ml dan diinkubasi selama 24 jam. Uji in vivo dilakukan dengan menginjeksikan bakteri  sebanyak 0,1 ml (109 cfu/ml secara intramuskular ke ikan gurame (berat 14 g dan kemudian ikan dipelihara dalam air yang mengandung ekstrak daun kirinyuh 15000 ppm. Hasil uji in virto menunjukkan bahwa semakin tinggi konsentrasi ekstrak daun kirinyuh basah semakin efektif dalam menghambat perkembangan

CARTOGRAPHIE DU PLASMIDE pSU100, PLASMIDE CRYPTIQUE DE LACTOBACILLUS CASEI

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F BENSALAH

2003-06-01

Ce plasmide appelé pSU100 a été cloné dans le vecteur de transformation pUC18 au site EcoRI chez E. coli JM103. Les profils électrophorétiques de restriction obtenus par des digestions simples, doubles et triples sous l’action de 33 endonucléases, ont contribué à l’élaboration d’une carte de restriction de ce plasmide. Cinq sites uniques ont été identifiés, ainsi que d’autres sites doubles et multiples. Une étude préliminaire du rôle physiologique de ce plasmide a permis de déceler une résistance à la kanamycine.

CARACTERIZAÇÃO DE AEROMONAS SPP ISOLADAS DE AMOSTRAS DE OSTRAS E ÁGUA POR MÉTODO MICROBIOLÓGICO E MOLECULAR

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Ana Carolina Miranda de Melo Silva

2014-09-01

Full Text Available This study aimed to isolate and identify Aeromonas bacteria from samples of oysters and water, by microbiological and molecular methods. Identification of Aeromonas was performed by the conventional method and by PCR and species characterization was performed by identification key Aerokey II and by RFLP-PCR of 16S rDNA. 59 (98.3% samples of oysters and 15 (75% samples of water contaminated by Aeromonas bacteria were identified. Of the 74 isolates of Aeromonas spp. obtained by microbiological analysis, 53 (71.62%, 38 (65.51% oyster samples and 15 (100% of water samples confirmed the characterization of the genus by molecular technique. As to biochemical species identification, 59.3% (n = 35 and 40.6% (n = 24 of isolates from Aeromonas sp. obtained from oyster samples were rated as A. hydrophila and A. caviae, respectively; and from isolates obtained from water samples, 60% (n = 9 were classified as A. hydrophila and 40% (n = 6 as A. caviae; however, only the A. hydrophila was confirmed by genetic sequencing. Regarding the classification by RFLP-PCR 16S rDNA, patterns of nonspecific bands were obtained, making it impossible to identify the species by this technique. The large number of oyester samples contaminated with Aeromonas spp. and identification of A. hydrophila, demonstrate that this mollusk might present a risk to consumer health, mainly because it is consumed raw and is to a potentially pathogenic micro-organism to humans.

A rapid MALDI-TOF MS identification database at genospecies level for clinical and environmental Aeromonas strains.

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Cinzia Benagli

Full Text Available The genus Aeromonas has undergone a number of taxonomic and nomenclature revisions over the past 20 years, and new (subspecies and biogroups are continuously described. Standard identification methods such as biochemical characterization have deficiencies and do not allow clarification of the taxonomic position. This report describes the development of a matrix-assisted laser desorption/ionisation-time of flight mass spectrometry (MALDI-TOF MS identification database for a rapid identification of clinical and environmental Aeromonas isolates.

A prospective study on Aeromonas in outpatients with diarrhea in the central region of Rio Grande do Sul State

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Karoline de Campos Prediger

2012-09-01

Full Text Available Aeromonas spp. were identified in five (2,7% of 182 diarrheal stool cultures, A. caviae was predominant, resistant mainly to ampicillin and cephalotin. This is the first study showing the presence of Aeromonas spp. in diarrheal stools of outpatients in the central region of Rio Grande do Sul State, Brazil.

Chlamydial plasmids and bacteriophages.

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Pawlikowska-Warych, Małgorzata; Śliwa-Dominiak, Joanna; Deptuła, Wiesław

2015-01-01

Chlamydia are absolute pathogens of humans and animals; despite being rather well recognised, they are still open for discovery. One such discovery is the occurrence of extrachromosomal carriers of genetic information. In prokaryotes, such carriers include plasmids and bacteriophages, which are present only among some Chlamydia species. Plasmids were found exclusively in Chlamydia (C.) trachomatis, C. psittaci, C. pneumoniae, C. suis, C. felis, C. muridarum and C. caviae. In prokaryotic organisms, plasmids usually code for genes that facilitate survival of the bacteria in the environment (although they are not essential). In chlamydia, their role has not been definitely recognised, apart from the fact that they participate in the synthesis of glycogen and encode proteins responsible for their virulence. Furthermore, in C. suis it was evidenced that the plasmid is integrated in a genomic island and contains the tetracycline-resistance gene. Bacteriophages specific for chlamydia (chlamydiaphages) were detected only in six species: C. psittaci, C. abortus, C. felis, C. caviae C. pecorum and C. pneumoniae. These chlamydiaphages cause inhibition of the developmental cycle, and delay transformation of reticulate bodies (RBs) into elementary bodies (EBs), thus reducing the possibility of infecting other cells in time. Plasmids and bacteriophages can be used in the diagnostics of chlamydioses; although especially in the case of plasmids, they are already used for detection of chlamydial infections. In addition, bacteriophages could be used as therapeutic agents to replace antibiotics, potentially addressing the problem of increasing antibiotic-resistance among chlamydia.

Antibacterial efficacies of some plant extracts against Aeromonas and Pseudomonas diseases of farmed catfish (Heterobranchus longifilis

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Albert P. Ekanem

2011-11-01

Full Text Available Aeromonas and Pseudomonas diseases are responsible for mortalities of some farmed catfish in Nigeria. The objective of the study is to investigate the efficacies of extracts of some plants against Aeromonas and Pseudomonas diseases of Heterobranchus longifilis. Ethanol extracts of Phyllanthus amarus, Allium sativum, Artemisia annua, Citrus limon, Moringa oleifera, Allium cepa and Azadirachta indica were tested against Aeromonas hydrophila and Pseudomonas flourescens of H. longifilis by disc diffusion assay. Extracts of P. amarus, A. sativum, A. annua and C. limon were significantly (P<0.05 more sensitive to A. hydrophila and P. flourescens than M. oleifera, A. cepa and A. indica which were effective against P. flourescens. Minimum inhibitory concentrations (MIC of the extracts were 25mg/ml for P. amarus and A. annua; 25 and 100mg/ml for C. lemon and A. cepa respectively and 50mg/ml for A. indica.  Alkaloid was demonstrated in all plants except A. annua by qualitative methods. Moderate amount (++ of cardiac glycosides was demonstrated in A. sativum, M. oleifera and P. amarus. Saponin (+++ was present in M. oleifera and A. indica while, tannin (++ was present in M. oleifera, P. amarus and A. indica respectively. Phlobatanins and Anthraquinones (++ were present in P. amarus and M. oleifera respectively.  Extracts of aforementioned plants have potentials as therapy against Aeromonas hydrophila and Pseudomonas flourescens of farmed catfish.

Large-scale preparation of plasmid DNA.

Science.gov (United States)

Heilig, J S; Elbing, K L; Brent, R

2001-05-01

Although the need for large quantities of plasmid DNA has diminished as techniques for manipulating small quantities of DNA have improved, occasionally large amounts of high-quality plasmid DNA are desired. This unit describes the preparation of milligram quantities of highly purified plasmid DNA. The first part of the unit describes three methods for preparing crude lysates enriched in plasmid DNA from bacterial cells grown in liquid culture: alkaline lysis, boiling, and Triton lysis. The second part describes four methods for purifying plasmid DNA in such lysates away from contaminating RNA and protein: CsCl/ethidium bromide density gradient centrifugation, polyethylene glycol (PEG) precipitation, anion-exchange chromatography, and size-exclusion chromatography.

Plasmid and chromosome partitioning: surprises from phylogeny

DEFF Research Database (Denmark)

Gerdes, Kenn; Møller-Jensen, Jakob; Bugge Jensen, Rasmus

2000-01-01

Plasmids encode partitioning genes (par) that are required for faithful plasmid segregation at cell division. Initially, par loci were identified on plasmids, but more recently they were also found on bacterial chromosomes. We present here a phylogenetic analysis of par loci from plasmids and chr...

Conjugal properties of the Sinorhizobium meliloti plasmid mobilome.

Science.gov (United States)

Pistorio, Mariano; Giusti, María A; Del Papa, María F; Draghi, Walter O; Lozano, Mauricio J; Tejerizo, Gonzalo Torres; Lagares, Antonio

2008-09-01

The biology and biochemistry of plasmid transfer in soil bacteria is currently under active investigation because of its central role in prokaryote adaptation and evolution. In this work, we examined the conjugal properties of the cryptic plasmids present in a collection of the N(2)-fixing legume-symbiont Sinorhizobium meliloti. The study was performed on 65 S. meliloti isolates recovered from 25 humic soils of Argentina, which were grouped into 22 plasmid-profile types [i.e. plasmid operational taxonomic units (OTUs)]. The cumulative Shannon index calculated for the observed plasmid profiles showed a clear saturation plateau, thus indicating an adequate representation of the S. meliloti plasmid-profile types in the isolates studied. The results show that isolates of nearly 14% of the plasmid OTUs hosted transmissible plasmids and that isolates of 29% of the plasmid OTUs were able to retransfer the previously characterized mobilizable-cryptic plasmid pSmeLPU88b to a third recipient strain. It is noteworthy that isolates belonging to 14% of the plasmid OTUs proved to be refractory to the entrance of the model plasmid pSmeLPU88b, suggesting either the presence of surface exclusion phenomena or the occurrence of restriction incompatibility with the incoming replicon. Incompatibility for replication between resident plasmids and plasmid pSmeLPU88b was observed in c. 20% of the OTUs. The results reported here reveal a widespread compatibility among the conjugal functions of the cryptic plasmids in S. meliloti, and this fact, together with the observed high proportion of existing donor genotypes, points to the extrachromosomal compartment of the species as being an extremely active plasmid mobilome.

Expansion of the IncX plasmid family for improved identification and typing of novel plasmids in drug-resistant Enterobacteriaceae

DEFF Research Database (Denmark)

Johnson, Timothy J.; Bielak, Eliza Maria; Fortini, Daniela

2012-01-01

and biofilm formation. Previous plasmid-based replicon typing procedures have indicated that the prevalence of IncX plasmids is low among members of the Enterobacteriaceae. However, examination of a number of IncX-like plasmid sequences and their occurrence in various organisms suggests that IncX plasmid...

Draft genome sequences of three Aeromonas hybrophila isolates from catfish and tilapia

Science.gov (United States)

Aeromonas hydrophila is a Gram-negative bacteria that is particularly adapted to freshwater environments and can cause severe infections in fish and humans. Here we report the draft genomes of three A. hydrophila catfish and tilapia isolates....

Aeromonas molluscorum Av27 is a potential tributyltin (TBT) bioremediator: phenotypic and genotypic characterization indicates its safe application.

Science.gov (United States)

Cruz, Andreia; Areias, Dário; Duarte, Ana; Correia, António; Suzuki, Satoru; Mendo, Sónia

2013-09-01

Aeromonas molluscorum Av27 is an estuarine bacterium highly resistant to tributyltin (TBT). Also, the strain is able to degrade TBT into the less toxic compounds dibutyltin and monobutyltin. Therefore, this bacterium has potential to be employed in bioremediation processes. In this context, defining its biological safety is crucial. With that purpose a number of intrinsic characteristics, usually present/associated with virulent strains, were investigated. Few virulence factors were detected in strain Av27. For instance, a DNase gene is present, but it is not apparently expressed in vitro. Motility, adherence factor and phospholipase activity were also detected. Additionally, cytotoxicity to Vero cells was negative. Resistance to penicillin (10 μg ml(-1)), amoxicillin/clavulanic acid (30 μg ml(-1)) and cephalothin (30 μg ml(-1)) and also to the vibriostatic agent O/129 was observed. Five plasmids (4, 7, 10, 100 kb and one greater than 100 kb) were identified. No Class I and II integrons were detected. Study of the optimal growth conditions showed that Av27 easily adapts to different environmental conditions. Overall, the results suggest that A. molluscorum Av27 can be considered safe to use to bioremediate TBT in contaminated environments.

Necrotizing Fasciitis Secondary to Aeromonas Infection Presenting with Septic Shock

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Nikhil Bhatia

2017-01-01

Full Text Available This report describes a case of necrotizing fasciitis presenting with septic shock due to an Aeromonas infection. The patient cut his foot while mowing the lawn and then spent time in a pool with black mold. He began feeling ill and developed swelling and a quarter-sized black area on his right lower extremity. Despite being hemodynamically unstable with systolic blood pressure in the low 70s, the patient was transferred to our facility from outside hospital 100 miles away. Upon arriving to facility, the patient appeared to be septic and the infected area of skin had grown. Irrigation and debridement were performed and appropriate antibiotic therapy was given; however, the patient subsequently died on hospital day 8. On review of the literature, cases of necrotizing fasciitis due to Aeromonas infection have been treated successfully with the aforementioned therapy; however, there is high mortality associated with these infections, many times related to a delayed diagnosis. Our patient also had multiple poor prognostic factors including hepatic dysfunction and immunosuppression.

Antibiogram, Adhesive Characteristics, and Incidence of Class 1 Integron in Aeromonas Species Isolated from Two South African Rivers

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Isoken H. Igbinosa

2013-01-01

Full Text Available Aeromonas species are well distributed in freshwater environments, and their natural susceptibility to antimicrobials renders them interesting candidates for the survey of antimicrobial resistance in freshwater milieu. Water samples were collected from Kat and Tyume rivers in the Eastern Cape province of South Africa, and a total of 45 isolates identified as Aeromonas species were recovered from the two rivers. All Aeromonas isolates were resistant to oxacillin, penicillin, clindamycin, cephalothin, vancomycin, and rifamycin, while appreciable susceptibilities (89.3 : 94.1%, 82.1 : 94.1%, 85.7 : 88.2%, and 92.9 : 88.2% were observed against ciprofloxacin, chloramphenicol, nitrofurantoin, and gentamicin from Kat and Tyume rivers, respectively. Multiple antibiotic resistance (MAR indices ranged from 0.016 to 0.044 for the two rivers. Class 1 integron was detected in about 20% of the isolates, and all the isolates except one showed ability to produce biofilm in vitro as weak producers (53.33%, moderate producers (15.56%, and strong producers (28.9%. This investigation provides a baseline data on antibiotic resistance as well as the adhesive characteristics of Aeromonas isolates from Tyume and Kat rivers in the Eastern Cape province of South Africa.

Impact of co-carriage of IncA/C plasmids with additional plasmids on the transfer of antimicrobial resistance in Salmonella enterica isolates.

Science.gov (United States)

Han, Jing; Pendleton, Sean J; Deck, Joanna; Singh, Ruby; Gilbert, Jeffrey; Johnson, Timothy J; Sanad, Yasser M; Nayak, Rajesh; Foley, Steven L

2018-04-20

Antimicrobial resistance in Salmonella enterica is often plasmid encoded. A key resistance plasmid group is the incompatibility group (Inc) A/C plasmids that often carry multiple resistance determinants. Previous studies showed that IncA/C plasmids were often co-located with other plasmids. The current study was undertaken to evaluate the impact of plasmid co-carriage on antimicrobial resistance and plasmid transfer. A total of 1267 Salmonella isolates, representing multiple serotypes and sources were previously subjected to susceptibility testing and 251 isolates with resistance to at least 5 antimicrobial agents were identified for further study. Each isolate was subjected to PCR-based replicon typing, and those with IncA/C plasmids were selected for plasmid isolation, PCR-based mapping of IncA/C plasmid backbone genes, and conjugation assays to evaluate resistance plasmid transferability. Of the 87 identified IncA/C positive isolates, approximately 75% carried a plasmid with another identified replicon type, with the most common being I1 (39%), FIA, FIIA, FIB and HI2 (each 15%). PCR-based mapping indicated significant diversity in IncA/C backbone content, especially in regions encoding transfer-associated and hypothetical proteins. Conjugation experiments showed that nearly 68% of the isolates transferred resistance plasmids, with 90% containing additional identified plasmids or larger (>50 kb) non-typeable plasmids. The majority of IncA/C-positive strains were able to conjugally transfer antimicrobial resistance to the recipient, encoded by IncA/C and/or co-carried plasmids. These findings highlight the importance of co-located plasmids for resistance dissemination either by directly transferring resistance genes or by potentially providing the needed conjugation machinery for IncA/C plasmid transfer. Copyright © 2018. Published by Elsevier B.V.

An investigation of the bactericidal activity of selected essential oils to Aeromonas spp.

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Clifford E. Starliper

2015-01-01

Full Text Available Diseases of fishes caused by Aeromonas spp. are common, have broad host ranges and may cause high mortality. Treatments of captive-reared populations using antimicrobials are limited with concerns for bacterial resistance development and environmental dissemination. This study was done to determine whether selected plant-derived essential oils were bactericidal to Aeromonas spp. Initially, twelve essential oils were evaluated using a disk diffusion assay to an isolate of A. salmonicida subsp. salmonicida, cause of fish furunculosis. The greatest zones of inhibition were obtained with oils of cinnamon Cinnamomum cassia, oregano Origanum vulgare, lemongrass Cymbopogon citratus and thyme Thymus vulgaris. Minimum bactericidal concentrations (MBC’s were determined for these four oils, Allimed® (garlic extract, Allium sativum and colloidal silver to sixty-nine isolates representing nine Aeromonas spp. The lowest mean MBCs (0.02–0.04% were obtained with three different sources of cinnamon oil. MBCs for three sources of oregano and lemongrass oils ranged from 0.14% to 0.30% and 0.10% to 0.65%, respectively, and for two thyme oils were 2.11% and 2.22%. The highest concentration (5% of Allimed® tested resulted in MBCs to twelve isolates. A concentration of silver greater than 15 mg/L would be required to determine MBCs for all but one isolate.

[Role of Aeromonas in the monitoring of a hydroecosystem in the Volga-Caspian area].

Science.gov (United States)

Obukhova, O V; Lartseva, L V; Lisitskaia, I A

2011-01-01

The paper gives data obtained over many years on the quantity of bacteria of the genus Aeromonas in the hydroecosystems of the delta of the Volga and Caspian Sea and in commercial fishes (sturgeon (Acipenseridae), pike perch (Stizostedion), carp (Cyprinus carpio), silurus (Silurus glanis), etc.). It provides a detailed analysis of their seasonal trends and spatial distribution, markers of their pathogenicity, and antibiotic resistance. The findings suggest that Aeromonas is a causative agent of sapronoses and meets the criteria for natural focal infections. They show a wide range of tolerance to the abiotic factors of hydroecosystems, as well as mixotrophy and autrophic nutrition in the environment and they are of great sanitary and hygienic importance.

Characterization of new plasmids from methylotrophic bacteria.

Science.gov (United States)

Brenner, V; Holubová, I; Benada, O; Hubácek, J

1991-07-01

Several tens of methanol-utilizing bacterial strains isolated from soil were screened for the presence of plasmids. From the obligate methylotroph Methylomonas sp. strain R103a plasmid pIH36 (36 kb) was isolated and its restriction map was constructed. In pink-pigmented facultative methylotrophs (PPFM), belonging to the genus Methylobacterium four plasmids were detected: plasmids pIB200 (200 kb) and pIB14 (14 kb) in the strain R15d and plasmids pWU14 (14 kb) and pWU7 (7.8 kb) in the strain M17. Because of the small size and the presence of several unique REN sites (HindIII, EcoRI, NcoI), plasmid pWU7 was chosen for the construction of a vector for cloning in methylotrophs. Cointegrates pKWU7A and pKWU7B were formed between pWU7 and the E. coli plasmid pK19 Kmr, which were checked for conjugative transfer from E. coli into the methylotrophic host.

Explanatory chapter: how plasmid preparation kits work.

Science.gov (United States)

Koontz, Laura

2013-01-01

To isolate plasmid DNA from bacteria using a commercial plasmid miniprep kit (if interested, compare this protocol with Isolation of plasmid DNA from bacteria). Copyright © 2013 Elsevier Inc. All rights reserved.

Recovery of atypical Aeromonas salmonicida from ulcerated fish from the Baltic Sea

DEFF Research Database (Denmark)

Wiklund, T.; Tabolina, I; Bezgachina, T.V.

1999-01-01

Ulcerated fish of six different species were collected during the BMB/ICES Sea-going Workshop "Fish Diseases and Parasites in the Baltic Sea", 25 November to 8 December 1994, and examined for bacteriological infections. Atypical Aeromonas salmonicida strains were isolated from the majority...

Identification of IncA/C Plasmid Replication and Maintenance Genes and Development of a Plasmid Multilocus Sequence Typing Scheme.

Science.gov (United States)

Hancock, Steven J; Phan, Minh-Duy; Peters, Kate M; Forde, Brian M; Chong, Teik Min; Yin, Wai-Fong; Chan, Kok-Gan; Paterson, David L; Walsh, Timothy R; Beatson, Scott A; Schembri, Mark A

2017-02-01

Plasmids of incompatibility group A/C (IncA/C) are becoming increasingly prevalent within pathogenic Enterobacteriaceae They are associated with the dissemination of multiple clinically relevant resistance genes, including bla CMY and bla NDM Current typing methods for IncA/C plasmids offer limited resolution. In this study, we present the complete sequence of a bla NDM-1 -positive IncA/C plasmid, pMS6198A, isolated from a multidrug-resistant uropathogenic Escherichia coli strain. Hypersaturated transposon mutagenesis, coupled with transposon-directed insertion site sequencing (TraDIS), was employed to identify conserved genetic elements required for replication and maintenance of pMS6198A. Our analysis of TraDIS data identified roles for the replicon, including repA, a toxin-antitoxin system; two putative partitioning genes, parAB; and a putative gene, 053 Construction of mini-IncA/C plasmids and examination of their stability within E. coli confirmed that the region encompassing 053 contributes to the stable maintenance of IncA/C plasmids. Subsequently, the four major maintenance genes (repA, parAB, and 053) were used to construct a new plasmid multilocus sequence typing (PMLST) scheme for IncA/C plasmids. Application of this scheme to a database of 82 IncA/C plasmids identified 11 unique sequence types (STs), with two dominant STs. The majority of bla NDM -positive plasmids examined (15/17; 88%) fall into ST1, suggesting acquisition and subsequent expansion of this bla NDM -containing plasmid lineage. The IncA/C PMLST scheme represents a standardized tool to identify, track, and analyze the dissemination of important IncA/C plasmid lineages, particularly in the context of epidemiological studies. Copyright © 2017 American Society for Microbiology.

Plasmid-mediated UV-protection in Streptococcus lactis

Energy Technology Data Exchange (ETDEWEB)

Chopin, M.C.; Rouault, A. (Institut National de la Recherche Agronomique, Rennes (France). Lab. de Recherches de Technologie Laitiere); Moillo-Batt, A. (Institut National de la Sante et de la Recherche Medicale (INSERM), Hopital de Pontchaillon, 35 - Rennes (France))

1985-02-01

Streptococcus lactis strain IL594 contains 9 plasmids, designated pIL1 to pIL9. On the basis of protoplast-induced curing experiments the authors showed that derivatives containing pIL7 were resistant to UV-irradiation while derivatives lacking pIL7 were sensitive. The pIL7-determined UV-protection was confirmed by co-transfer of the plasmid and of the character into a plasmid-free derivative of S. lactis IL594. Moreover, prophage induction required higher UV-fluence in this derivative carrying pIL7 than in the plasmid-free strain. This is the first report of a plasmid-mediated UV-protection in group N streptococci.

Plasmid-mediated UV-protection in Streptococcus lactis

International Nuclear Information System (INIS)

Chopin, M.-C.; Rouault, A.

1985-01-01

Streptococcus lactis strain IL594 contains 9 plasmids, designated pIL1 to pIL9. On the basis of protoplast-induced curing experiments the authors showed that derivatives containing pIL7 were resistant to UV-irradiation while derivatives lacking pIL7 were sensitive. The pIL7-determined UV-protection was confirmed by cotransfer of the plasmid and of the character into a plasmid-free derivative of S. lactis IL594. Moreover, prophage induction required higher UV-fluence in this derivative carrying pIL7 than in the plasmid-free strain. This is the first report of a plasmid-mediated UV-protection in group N streptococci. (orig.)

Population dynamics and antimicrobial susceptibility of Aeromonas spp. along a salinity gradient in an urban estuary in Northeastern Brazil.

Science.gov (United States)

Silva, Camila Magalhães; Evangelista-Barreto, Norma Suely; Vieira, Regine Helena Silva Dos Fernandes; Mendonça, Kamila Vieira; Sousa, Oscarina Viana de

2014-12-15

The main objective of this study was to quantify population and identify culturable species of Aeromonas in sediment and surface water collected along a salinity gradient in an urban estuary in Northeastern Brazil. Thirty sediment samples and 30 water samples were collected from 3 sampling locations (A, B and C) between October 2007 and April 2008. The Aeromonas count was 10-7050CFU/mL (A), 25-38,500CFU/mL (B) andwater samples, and ∼100-37,500CFU/g (A), 1200-43,500CFU/g (B) andantibiotics tested. Resistance to erythromycin was mostly plasmidial. In conclusion, due to pollution, the Cocó River is contaminated by pathogenic strains of Aeromonas spp. with a high incidence of antibacterial resistance, posing a serious risk to human health. Copyright © 2014 Elsevier Ltd. All rights reserved.

Behavior of IncQ Plasmids in Agrobacterium tumefaciens

NARCIS (Netherlands)

Hille, Jacques; Schilperoort, Rob

1981-01-01

Inc-Q plasmids were introduced into Agrobacterium tumefuciens, by mobilization from Escherichia coli with an Inc-P plasmid, or by transformation with purified plasmid DNA. It was found that they were stably maintained. The presence of an Inc-Q plasmid did not influence tumorigenicity. These results

Persistence Mechanisms of Conjugative Plasmids

DEFF Research Database (Denmark)

Bahl, Martin Iain; Hansen, Lars H.; Sørensen, Søren Johannes

2009-01-01

Are plasmids selfish parasitic DNA molecules or an integrated part of the bacterial genome? This chapter reviews the current understanding of the persistence mechanisms of conjugative plasmids harbored by bacterial cells and populations. The diversity and intricacy of mechanisms affecting the suc...

Draft Genome Sequence of Fish Pathogen Aeromonas bestiarum GA97-22.

Science.gov (United States)

Kumru, Salih; Tekedar, Hasan C; Griffin, Matt J; Waldbieser, Geoffrey C; Liles, Mark R; Sonstegard, Tad; Schroeder, Steven G; Lawrence, Mark L; Karsi, Attila

2018-06-14

Aeromonas bestiarum is a Gram-negative mesophilic motile bacterium causing acute hemorrhagic septicemia or chronic skin ulcers in fish. Here, we report the draft genome sequence of A. bestiarum strain GA97-22, which was isolated from rainbow trout in 1997. This genome sequence will improve our understanding of the complex taxonomy of motile aeromonads.

Aeromonas caviae strain induces Th1 cytokine response in mouse intestinal tract

Energy Technology Data Exchange (ETDEWEB)

Hayes, S L; Lye, D J; McKinstry, Craig A.; Vesper, Sephen J.

2010-01-01

Aeromonas caviae has been associated with human gastrointestinal disease. Strains of this species typically lack virulence factors (VFs) such as enterotoxins and hemolysins that are produced by other human pathogens of the Aeromonas genus. Microarray profiling of murine small intestinal extracts, 24 hours after oral infection with an A. caviae strain, provides evidence of a Th1 type immune response. A large number of gamma-interferon (γ-IFN) induced genes are up-regulated as well as several tumor necrosis factor-alpha (TNF-α) transcripts. A. caviae has always been considered as opportunistic pathogen because it lacks obvious virulence factors. This current effort suggests that an A. caviae strain can colonize the murine intestinal tract and cause what has been described by others as a dysregulatory cytokine response. This response could explain why a number of diarrheal waterborne disease cases have been attributed to A. caviae even though it lacks obvious enteropathogenic properties.

Plasmid-mediated mineralization of 4-chlorobiphenyl

International Nuclear Information System (INIS)

Shields, M.S.; Hooper, S.W.; Sayler, G.S.

1985-01-01

Strains of Alcaligenes and Acinetobacter spp. were isolated from a mixed culture already proven to be proficient at complete mineralization of monohalogenated biphenyls. These strains were shown to harbor a 35 x 10(6)-dalton plasmid mediating a complete pathway for 4-chlorobiphenyl (4CB) oxidation. Subsequent plasmid curing of these bacteria resulted in the abolishment of the 4CB mineralization phenotype and loss of even early 4CB metabolism by Acinetobacter spp. Reestablishment of the Alcaligenes plasmid, denoted pSS50, in the cured Acinetobacter spp. via filter surface mating resulted in the restoration of 4CB mineralization abilities. 4CB mineralization, however, proved to be an unstable characteristic in some subcultured strains. Such loss was not found to coincide with any detectable alteration in plasmid size. Cultures capable of complete mineralization, as well as those limited to partial metabolism of 4CB, produced 4-chlorobenzoate as a metabolite. Demonstration of mineralization of a purified 14 C-labeled chlorobenzoate showed it to be a true intermediate in 4CB mineralization. Unlike the mineralization capability, the ability to produce a metabolite has proven to be stable on subculture. These results indicate the occurrence of a novel plasmid, or evolved catabolic plasmid, that mediates the complete mineralization of 4CB

Construction of Biologically Functional Bacterial Plasmids In Vitro

Science.gov (United States)

Cohen, Stanley N.; Chang, Annie C. Y.; Boyer, Herbert W.; Helling, Robert B.

1973-01-01

The construction of new plasmid DNA species by in vitro joining of restriction endonuclease-generated fragments of separate plasmids is described. Newly constructed plasmids that are inserted into Escherichia coli by transformation are shown to be biologically functional replicons that possess genetic properties and nucleotide base sequences from both of the parent DNA molecules. Functional plasmids can be obtained by reassociation of endonuclease-generated fragments of larger replicons, as well as by joining of plasmid DNA molecules of entirely different origins. Images PMID:4594039

Prevalence of plasmid-bearing and plasmid-free Chlamydia trachomatis infection among women who visited obstetrics and gynecology clinics in Malaysia.

Science.gov (United States)

Yeow, Tee Cian; Wong, Won Fen; Sabet, Negar Shafiei; Sulaiman, Sofiah; Shahhosseini, Fatemeh; Tan, Grace Min Yi; Movahed, Elaheh; Looi, Chung Yeng; Shankar, Esaki M; Gupta, Rishien; Arulanandam, Bernard P; Hassan, Jamiyah; Abu Bakar, Sazaly

2016-03-18

The 7.5 kb cryptic plasmid of Chlamydia trachomatis has been shown to be a virulence factor in animal models, but its significance in humans still remains unknown. The aim of this study was to investigate the prevalence and potential involvement of the C. trachomatis cryptic plasmid in causing various clinical manifestations; including infertility, reproductive tract disintegrity, menstrual disorder, and polycystic ovarian syndrome (PCOS) among genital C. trachomatis-infected patients. A total of 180 female patients of child bearing age (mean 30.9 years old, IQR:27-35) with gynecological complications and subfertility issues, who visited Obstetrics and Gynecology clinics in Kuala Lumpur, Malaysia were recruited for the study. Prevalence of genital chlamydial infection among these patients was alarmingly high at 51.1% (92/180). Of the 92 chlamydia-infected patients, 93.5% (86/92) were infected with plasmid-bearing (+) C. trachomatis while the remaining 6.5% (6/92) were caused by the plasmid-free (-) variant. Our data showed that genital C. trachomatis infection was associated with infertility issues, inflammation in the reproductive tract (mucopurulent cervicitis or endometriosis), irregular menstrual cycles and polycystic ovarian syndrome (PCOS). However, no statistical significance was detected among patients with plasmid (+) versus plasmid (-) C. trachomatis infection. Interestingly, plasmid (+) C. trachomatis was detected in all patients with PCOS, and the plasmid copy numbers were significantly higher among PCOS patients, relative to non-PCOS patients. Our findings show a high incidence of C. trachomatis infection among women with infertility or gynecological problems in Malaysia. However, due to the low number of plasmid (-) C. trachomatis cases, a significant role of the plasmid in causing virulence in human requires further investigation of a larger cohort.

Genetic characterization of plasmid pRJ5 of Staphylococcus aureus compared to plasmid pE194

International Nuclear Information System (INIS)

Oliveira, S.S. de; Freire Bastos, M.C. de

1993-01-01

The pRJ5, a naturally occurring constitutive macrolide, lincosamide and streptogramin B (MLS) resistance plasmid of Staphylococcus aureus, was compared to pE194, a plasmid that confers the inducible phenotype. pRJ5 was stable in all strains of S. aureus tested, even under growth at 43 O C, which distinguished it from pE194 which was shown to be thermo-sensitive for replication. pRJ5, like pE194, was highly unstable in Bacillus subtilis when the cells were grown in nonselective conditions. Multimeric forms of pRJ5 DNA were detected in the few cells of B. subtilis that retained this plasmid. pE194 was transduced by phages φ 11 and φ 443 at frequencies 400 and 20-fold higher, respectively, than pRJ5. Both plasmids were co-transduced with the plasmid pRJ4. pRJ5 was shown to be compatible with pE194. Therefore they belong to distinct Inc groups. Hybridization studies revealed that pRJ5 shares a 1.35 kb region of homology to pE194, which is limited to the erm gene, conferring MLS resistance. (author)

Plasmid fermentation process for DNA immunization applications.

Science.gov (United States)

Carnes, Aaron E; Williams, James A

2014-01-01

Plasmid DNA for immunization applications must be of the highest purity and quality. The ability of downstream purification to efficiently produce a pure final product is directly influenced by the performance of the upstream fermentation process. While several clinical manufacturing facilities already have validated fermentation processes in place to manufacture plasmid DNA for use in humans, a simple and inexpensive laboratory-scale fermentation process can be valuable for in-house production of plasmid DNA for use in animal efficacy studies. This chapter describes a simple fed-batch fermentation process for producing bacterial cell paste enriched with high-quality plasmid DNA. A constant feeding strategy results in a medium cell density culture with continuously increasing plasmid amplification towards the end of the process. Cell banking and seed culture preparation protocols, which can dramatically influence final product yield and quality, are also described. These protocols are suitable for production of research-grade plasmid DNA at the 100 mg-to-1.5 g scale from a typical 10 L laboratory benchtop fermentor.

Antimicrobial susceptibility pattern and plasmid-mediated ...

African Journals Online (AJOL)

negative Staphylococci (CoNS) were isolated from clinical samples and isolates subjected to antibiotic susceptibility testing, plasmid curing and plasmid DNA isolation. Result: The highest percentages isolates were recovered from urine samples and ...

JST Thesaurus Headwords and Synonyms: Aeromonas salmonicida [MeCab user dictionary for science technology term[Archive

Lifescience Database Archive (English)

Full Text Available MeCab user dictionary for science technology term Aeromonas salmonicida 名詞 一般 * * *... * Ａｅｒｏｍｏｎａｓ　ｓａｌｍｏｎｉｃｉｄａ Ａｅｒｏｍｏｎａｓ　ｓａｌｍｏｎｉｃｉｄａ エイイーアールオーエムオーエヌエイエス　エスエイエルエムオーエヌアイシーアイディーエイ Thesaurus2015 200906081596351600 C LS07 UNKNOWN_2 Aeromonas salmonicida

Species Distribution and Prevalence of Putative Virulence Factors in Mesophilic Aeromonas spp. Isolated from Fresh Retail Sushi

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Sunniva Hoel

2017-05-01

Full Text Available Aeromonas spp. are ubiquitous bacteria that have received increasing attention as human pathogens because of their widespread occurrence in food, especially seafood and vegetables. The aim of this work was to assess the species identity and phylogenetic relationship of 118 Aeromonas strains isolated from fresh retail sushi from three producers, and to characterize the isolates with respect to genetic and phenotypic virulence factors. We also evaluate the potential hazard associated with their presence in ready-to-eat seafood not subjected to heat treatment. Mesophilic Aeromonas salmonicida was most prevalent (74%, followed by A. bestiarum (9%, A. dhakensis (5%, A. caviae (5%, A. media (4%, A. hydrophila (2%, and A. piscicola (1%. All isolates were considered potentially pathogenic due to the high prevalence of genes encoding hemolysin (hlyA (99%, aerolysin (aerA (98%, cytotoxic enterotoxin (act (86%, heat-labile cytotonic enterotoxin (alt (99%, and heat-stable cytotonic enterotoxin (ast (31%. The shiga-like toxins 1 and 2 (stx-1 and stx-2 were not detected. Moreover, there was heterogeneity in toxin gene distribution among the isolates, and the combination of act/alt/hlyA/aerA was most commonly detected (63%. β-hemolysis was species-dependent and observed in 91% of the isolates. All A. media and A. caviae strains were non-hemolytic. For isolates belonging to this group, lack of hemolysis was possibly related to the absence of the act gene. Swimming motility, linked to adhesion and host invasion, occurred in 65% of the isolates. Partial sequencing of the gyrB gene demonstrated its suitability as a genetic marker for Aeromonas species identification and for assessment of the phylogenetic relationship between the isolates. The gyrB sequence divergence within a given species ranged from 1.3 to 2.9%. A. bestiarum, A. salmonicida, and A. piscicola were the most closely related species; their sequences differed by 2.7–3.4%. The average gyrB sequence

Chlorinated and ultraviolet radiation -treated reclaimed irrigation water is the source of Aeromonas found in vegetables used for human consumption

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Latif-Eugenín, Fadua; Beaz-Hidalgo, Roxana; Silvera-Simón, Carolina [Unidad de Microbiología, Facultad de Medicina y Ciencias de la Salud, IISPV, Universidad Rovira i Virgili, Reus (Spain); Fernandez-Cassi, Xavi [Departamento de Microbiología, Facultad de Biología, Universidad de Barcelona, Barcelona (Spain); Figueras, María J., E-mail: mariajose.figueras@urv.cat [Unidad de Microbiología, Facultad de Medicina y Ciencias de la Salud, IISPV, Universidad Rovira i Virgili, Reus (Spain)

2017-04-15

Wastewater is increasingly being recognized as a key water resource, and reclaimed water (or treated wastewater) is used for irrigating vegetables destined for human consumption. The aim of the present study was to determine the diversity and prevalence of Aeromonas spp. both in reclaimed water used for irrigation and in the three types of vegetables irrigated with that water. Seven of the 11 (63.6%) samples of reclaimed water and all samples of vegetables were positive for the presence of Aeromonas. A total of 216 Aeromonas isolates were genotyped and corresponded to 132 different strains that after identification by sequencing the rpoD gene belonged to 10 different species. The prevalence of the species varied depending on the type of sample. In the secondary treated reclaimed water A. caviae and A. media dominated (91.4%) while A. salmonicida, A. media, A. allosaccharophila and A. popoffii represented 74.0% of the strains in the irrigation water. In vegetables, A. caviae (75.0%) was the most common species, among which a strain isolated from lettuce had the same genotype (ERIC pattern) as a strain recovered from the irrigation water. Furthermore, the same genotype of the species A. sanarellii was recovered from parsley and tomatoes demonstrating that irrigation water was the source of contamination and confirming the risk for public health. - Highlights: • Reclaimed water (= treated wastewater) is used for the irrigation of vegetables. • Aeromonas was found in reclaimed water and irrigated vegetables with this water. • The prevalence of Aeromonas spp. varied between irrigation water and vegetables. • Epidemiological relationships were found between irrigation water and vegetables. • The water was the source of contamination which means a risk for the public health.

Chlorinated and ultraviolet radiation -treated reclaimed irrigation water is the source of Aeromonas found in vegetables used for human consumption

International Nuclear Information System (INIS)

Latif-Eugenín, Fadua; Beaz-Hidalgo, Roxana; Silvera-Simón, Carolina; Fernandez-Cassi, Xavi; Figueras, María J.

2017-01-01

Wastewater is increasingly being recognized as a key water resource, and reclaimed water (or treated wastewater) is used for irrigating vegetables destined for human consumption. The aim of the present study was to determine the diversity and prevalence of Aeromonas spp. both in reclaimed water used for irrigation and in the three types of vegetables irrigated with that water. Seven of the 11 (63.6%) samples of reclaimed water and all samples of vegetables were positive for the presence of Aeromonas. A total of 216 Aeromonas isolates were genotyped and corresponded to 132 different strains that after identification by sequencing the rpoD gene belonged to 10 different species. The prevalence of the species varied depending on the type of sample. In the secondary treated reclaimed water A. caviae and A. media dominated (91.4%) while A. salmonicida, A. media, A. allosaccharophila and A. popoffii represented 74.0% of the strains in the irrigation water. In vegetables, A. caviae (75.0%) was the most common species, among which a strain isolated from lettuce had the same genotype (ERIC pattern) as a strain recovered from the irrigation water. Furthermore, the same genotype of the species A. sanarellii was recovered from parsley and tomatoes demonstrating that irrigation water was the source of contamination and confirming the risk for public health. - Highlights: • Reclaimed water (= treated wastewater) is used for the irrigation of vegetables. • Aeromonas was found in reclaimed water and irrigated vegetables with this water. • The prevalence of Aeromonas spp. varied between irrigation water and vegetables. • Epidemiological relationships were found between irrigation water and vegetables. • The water was the source of contamination which means a risk for the public health.

Presence of Vibrios and Aeromonas strains and total psychrotrophs in hexagonal spotted grouper and Spanish Mackerel Fish

International Nuclear Information System (INIS)

Al-Dagal, M.

2002-01-01

This work was conducted on different parts of hexagonal-spotted grouper and Spanish mackerel fish from 10 major fishery shops in Riyadh city to assess the presence of vibrios and aeromonas using the API20E and Biolog system. Also, pH and total psychotrophs were assessed as two indexes of quality. Similar data were obtained from both identification systems except for Aeromonas media-like and Vibrio anguillarum which are not included in the API20E database. Aeromonas hydrophila, A. media-like, V. alginolyticus, V.anguillarum, V. damsel and V. fluvialis were recovered from fish samples A. medial-like and V. damsel most predominant. Unexpectedly, V. cholera and V. parahemolyticus were not recovered. The numbers of skin samples of grouper having more than 7 log CFU/gm were much higher than that of mackerel skin samples. Similar psychrotrophic counts were noticed in gut samples of the two fish types, indicating similarly in growth habitat. Most of the grouper fish samples had a pH in the range of >6.40-7.02, whereas 95% of mackerel samples had a pH at 6.40 or below. (author)

Novel plasmids and resistance phenotypes in Yersinia pestis: unique plasmid inventory of strain Java 9 mediates high levels of arsenic resistance.

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Eppinger, Mark; Radnedge, Lyndsay; Andersen, Gary; Vietri, Nicholas; Severson, Grant; Mou, Sherry; Ravel, Jacques; Worsham, Patricia L

2012-01-01

Growing evidence suggests that the plasmid repertoire of Yersinia pestis is not restricted to the three classical virulence plasmids. The Java 9 strain of Y. pestis is a biovar Orientalis isolate obtained from a rat in Indonesia. Although it lacks the Y. pestis-specific plasmid pMT, which encodes the F1 capsule, it retains virulence in mouse and non-human primate animal models. While comparing diverse Y. pestis strains using subtractive hybridization, we identified sequences in Java 9 that were homologous to a Y. enterocolitica strain carrying the transposon Tn2502, which is known to encode arsenic resistance. Here we demonstrate that Java 9 exhibits high levels of arsenic and arsenite resistance mediated by a novel promiscuous class II transposon, named Tn2503. Arsenic resistance was self-transmissible from Java 9 to other Y. pestis strains via conjugation. Genomic analysis of the atypical plasmid inventory of Java 9 identified pCD and pPCP plasmids of atypical size and two previously uncharacterized cryptic plasmids. Unlike the Tn2502-mediated arsenic resistance encoded on the Y. enterocolitica virulence plasmid; the resistance loci in Java 9 are found on all four indigenous plasmids, including the two novel cryptic plasmids. This unique mobilome introduces more than 105 genes into the species gene pool. The majority of these are encoded by the two entirely novel self-transmissible plasmids, which show partial homology and synteny to other enterics. In contrast to the reductive evolution in Y. pestis, this study underlines the major impact of a dynamic mobilome and lateral acquisition in the genome evolution of the plague bacterium.

Novel plasmids and resistance phenotypes in Yersinia pestis: unique plasmid inventory of strain Java 9 mediates high levels of arsenic resistance.

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Mark Eppinger

Full Text Available Growing evidence suggests that the plasmid repertoire of Yersinia pestis is not restricted to the three classical virulence plasmids. The Java 9 strain of Y. pestis is a biovar Orientalis isolate obtained from a rat in Indonesia. Although it lacks the Y. pestis-specific plasmid pMT, which encodes the F1 capsule, it retains virulence in mouse and non-human primate animal models. While comparing diverse Y. pestis strains using subtractive hybridization, we identified sequences in Java 9 that were homologous to a Y. enterocolitica strain carrying the transposon Tn2502, which is known to encode arsenic resistance. Here we demonstrate that Java 9 exhibits high levels of arsenic and arsenite resistance mediated by a novel promiscuous class II transposon, named Tn2503. Arsenic resistance was self-transmissible from Java 9 to other Y. pestis strains via conjugation. Genomic analysis of the atypical plasmid inventory of Java 9 identified pCD and pPCP plasmids of atypical size and two previously uncharacterized cryptic plasmids. Unlike the Tn2502-mediated arsenic resistance encoded on the Y. enterocolitica virulence plasmid; the resistance loci in Java 9 are found on all four indigenous plasmids, including the two novel cryptic plasmids. This unique mobilome introduces more than 105 genes into the species gene pool. The majority of these are encoded by the two entirely novel self-transmissible plasmids, which show partial homology and synteny to other enterics. In contrast to the reductive evolution in Y. pestis, this study underlines the major impact of a dynamic mobilome and lateral acquisition in the genome evolution of the plague bacterium.

Multilocus sequence typing of IncN plasmids

DEFF Research Database (Denmark)

García-Fernández, Aurora; Villa, Laura; Moodley, Arshnee

2011-01-01

that spread and persistence of this particular IncN-carrying blaVIM-1 lineage in Greece. CONCLUSIONS: This study proposes the use of pMLST as a suitable and rapid method for identification of IncN epidemic plasmid lineages. The recent spread of blaCTX-M-1 among humans and animals seems to be associated......OBJECTIVES: Incompatibility group N (IncN) plasmids have been associated with the dissemination of antimicrobial resistance and are a major vehicle for the spread of blaVIM-1 in humans and blaCTX-M-1 in animals. A plasmid multilocus sequence typing (pMLST) scheme was developed for rapid...... in different countries from both animals and humans belonged to ST1, suggesting dissemination of an epidemic plasmid through the food chain. Fifteen of 17 plasmids carrying blaVIM-1 from Klebsiella pneumoniae and Escherichia coli, isolated during a 5year period in Greece were assigned to ST10, suggesting...

Selfish restriction modification genes: resistance of a resident R/M plasmid to displacement by an incompatible plasmid mediated by host killing.

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Naito, Y; Naito, T; Kobayashi, I

1998-01-01

Previous work from this laboratory demonstrated that plasmids carrying a type II restriction-modification gene complex are not easily lost from their bacterial host because plasmid-free segregant cells are killed through chromosome cleavage. Here, we have followed the course of events that takes place when an Escherichia coli rec BC sbcA strain carrying a plasmid coding for the PaeR7I restriction-modification (R/M) gene complex is transformed by a plasmid with an identical origin of replication. The number of transformants that appeared was far fewer than with the restriction-minus (r-) control. Most of the transformants were very small. After prolonged incubation, the number and the size of the colonies increased, but this increase never attained the level of the r- control. Most of the transformed colonies retained the drug-resistance of the resident, r+ m+ plasmid. These results indicate that post-segregational host killing occurs when a plasmid bearing an R/M gene complex is displaced by an incompatible plasmid. Such cell killing eliminates the competitor plasmid along with the host and, thus, would allow persistence of the R/M plasmid in the neighboring, clonal host cells in nature. This phenomenon is reminiscent of mammalian apoptosis and other forms of altruistic cell death strategy against infection. This type of resistance to displacement was also studied in a wild type Escherichia coli strain that was normal for homologous recombination (rec+). A number of differences between the recBC sbcA strain and the rec+ strain were observed and these will be discussed.

Characterization of pLAC1, a cryptic plasmid isolated from Lactobacillus acidipiscis and comparative analysis with its related plasmids.

Science.gov (United States)

Asteri, Ioanna-Areti; Papadimitriou, Konstantinos; Boutou, Effrossyni; Anastasiou, Rania; Pot, Bruno; Vorgias, Constantinos E; Tsakalidou, Effie

2010-07-15

The pLAC1 plasmid of Lactobacillus acidipiscis ACA-DC 1533, a strain isolated from traditional Kopanisti cheese, was characterised. Nucleotide sequence analysis revealed a circular molecule of 3478bp with a G+C content of 37.2%. Ab initio annotation indicated four putative open reading frames (orfs). orf1 and orf4 were found to encode a replication initiation protein (Rep) and a mobilization protein (Mob), respectively. The deduced products of orf2 and orf3 revealed no significant homology to other known proteins. However, in silico examination of the plasmid sequence supported the existence of a novel operon that includes rep, orf2 and orf3 in pLAC1 and that this operon is highly conserved also in plasmids pLB925A02, pSMA23, pLC88 and pC7. RT-PCR experiments allowed us to verify that these three genes are co-transcribed as a single polycistronic mRNA species. Furthermore, phylogenetic analysis of pLAC1 Rep and Mob proteins demonstrated that they may have derived from different plasmid origins, suggesting that pLAC1 is a product of a modular evolution process. Comparative analysis of full length nucleotide sequences of pLAC1 and related Lactobacillus plasmids showed that pLAC1 shares a very similar replication backbone with pLB925A02, pSMA23 and pLC88. In contrast, mob of pLAC1 was almost identical with the respective gene of plasmids pLAB1000, pLB4 and pPB1. These findings lead to the conclusion that pLAC1 acquired mob probably via an ancestral recombination event. Our overall work highlights the importance of characterizing plasmids deriving from non-starter 'wild' isolates in order to better appreciate plasmid divergence and evolution of lactic acid bacteria. 2010 Elsevier B.V. All rights reserved.

Role of pH in oxidase variability of Aeromonas hydrophila.

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Hunt, L K; Overman, T L; Otero, R B

1981-01-01

Some strains of Aeromonas hydrophila may be oxidase negative or only weakly oxidase positive by the Kovacs method taken from the surface of a differential medium, such as MacConkey agar. Six strains of A. hydrophila, two oxidase variable, one oxidase constant, and three weakly oxidase positive on MacConkey agar, were studied to determine the cause of oxidase variability. The bacteriostatic dyes in MacConkey agar were considered possible inhibitors of the oxidase reaction. The concentration of...

Compatibility and entry exclusion of IncA and IncC plasmids revisited: IncA and IncC plasmids are compatible.

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Ambrose, Stephanie J; Harmer, Christopher J; Hall, Ruth M

2018-02-24

In an early study, IncA and IncC plasmids that were reported to be compatible were grouped as the "A-C complex" based on similarities and on strong entry exclusion. However, recently, the term IncA/C has been used frequently to describe plasmids belonging to both of these two groups. Granted that the supporting data was not included in the original reports and that the consensus iteron sequences have since been shown to be essentially identical, we have addressed the question again. The original IncA plasmid, RA1, and the IncC plasmid pRMH760, were introduced into the same cell by transformation, and were found to be maintained stably for over 100 generations in the absence of selection for either plasmid, i.e. they were compatible. We conclude that use of the term IncA/C for this important plasmid group is indeed incorrect and it causes unnecessary confusion. Granted the importance of IncC plasmids in the spread of antibiotic resistance genes, we recommend that use of the misleading terms IncA/C, IncA/C 1 and IncA/C 2 should cease. In addition, RA1 and pRMH760 were shown to each completely prevent entry of the other via conjugative transfer into the cell they reside in. Copyright © 2018 Elsevier Inc. All rights reserved.

Ecological and genetic determinants of plasmid distribution in Escherichia coli.

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Medaney, Frances; Ellis, Richard J; Raymond, Ben

2016-11-01

Bacterial plasmids are important carriers of virulence and antibiotic resistance genes. Nevertheless, little is known of the determinants of plasmid distribution in bacterial populations. Here the factors affecting the diversity and distribution of the large plasmids of Escherichia coli were explored in cattle grazing on semi-natural grassland, a set of populations with low frequencies of antibiotic resistance genes. Critically, the population genetic structure of bacterial hosts was chararacterized. This revealed structured E. coli populations with high diversity between sites and individuals but low diversity within cattle hosts. Plasmid profiles, however, varied considerably within the same E. coli genotype. Both ecological and genetic factors affected plasmid distribution: plasmid profiles were affected by site, E. coli diversity, E. coli genotype and the presence of other large plasmids. Notably 3/26 E. coli serotypes accounted for half the observed plasmid-free isolates indicating that within species variation can substantially affect carriage of the major conjugative plasmids. The observed population structure suggest that most of the opportunities for within species plasmid transfer occur between different individuals of the same genotype and support recent experimental work indicating that plasmid-host coevolution, and epistatic interactions on fitness costs are likely to be important in determining occupancy. © 2016 The Authors. Environmental Microbiology published by Society for Applied Microbiology and John Wiley & Sons Ltd.

The characteristics of micrococcus (deinococcus) radiodurans sark plasmids

International Nuclear Information System (INIS)

Sjarief, Sri Hariani; Kikuchi, Masahiro; Watanabe, Hiroshi.

1994-01-01

The characterization of micrococcus (deinococcus) radiodurans sark plasmids. This bacterium has been classified as a new genus deinococcus radiodurans which is resistant to gamma-rays. It can repair itself completely almost all of DNA damages including double strand breaks induced by gamma-rays up to about 5 KGy. To reveal the repair mechanism, several investigations had been done to develop a cloning vector available for the genetic analysis. For this purpose D. radiodurans Sark are to be prepared as a vector by studying the characteristics of its plasmid. Plasmids were isolated by electrophoresis using 0.6% low-melting-temperature agarose in TAE and run for 5.5 hours, followed by the identification. An antibiotic marker was also carried out in this experiment to identify its location in the genetic materials of the cell, beside making a restriction map of the plasmid. Results have shown that D. radiodurans Sark has 4 plasmids (P1, P2, P3, and P4) and the refampicin resistant genes were not found in the plasmid. (authors). 14 refs; 4 figs

Resistance of Salmonds Against Aeromonas Salmonicida

DEFF Research Database (Denmark)

Holten-Andersen, Lars; Dalsgaard, Inger; Buchmann, Kurt

2011-01-01

Furunculosis, caused by Aeromonas salmonicida, continues to be a health problem for the growing salmonid aquaculture. Despite effective vaccination programs regular outbreaks occur at Danish trout farms calling for repeated antibiotic treatment. We hypothesized that a difference in natural...... over a 30-day period post challenge and the results were summarized in mortality curves. A. salmonicida was recovered from mortalities during the entire test period. At day 30 the survival was 6.2 % and 34.0 % for rainbow trout and Baltic salmon, respectively. Significant differences in susceptibility...... to A. salmonicida were demonstrated between the two salmonids and hazard ratio estimation between rainbow trout and Baltic salmon showed a 3.36 higher risk of dying from the infection in the former. The finding that Baltic salmon carries a high level of natural resistance to furunculosis might raise...

The broad-host-range plasmid pSFA231 isolated from petroleum-contaminated sediment represents a new member of the PromA plasmid family.

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Li, Xiaobin; Top, Eva M; Wang, Yafei; Brown, Celeste J; Yao, Fei; Yang, Shan; Jiang, Yong; Li, Hui

2014-01-01

A self-transmissible broad-host-range (BHR) plasmid pSFA231 was isolated from petroleum-contaminated sediment in Shen-fu wastewater irrigation zone, China, using the triparental mating exogenous plasmid capture method. Based on its complete sequence the plasmid has a size of 41.5 kb and codes for 50 putative open reading frames (orfs), 29 of which represent genes involved in replication, partitioning and transfer functions of the plasmid. Phylogenetic analysis grouped pSFA231 into the newly defined PromA plasmid family, which currently includes five members. Further comparative genomic analysis shows that pSFA231 shares the common backbone regions with the other PromA plasmids, i.e., genes involved in replication, maintenance and control, and conjugative transfer. Nevertheless, phylogenetic divergence was found in specific gene products. We propose to divide the PromA group into two subgroups, PromA-α (pMRAD02, pSB102) and PromA-β (pMOL98, pIPO2T, pSFA231, pTer331), based on the splits network analysis of the RepA protein. Interestingly, a cluster of hypothetical orfs located between parA and traA of pSFA231 shows high similarity with the corresponding regions on pMOL98, pIPO2T, and pTer331, suggesting these hypothetical orfs may represent "essential" plasmid backbone genes for the PromA-β subgroup. Alternatively, they may also be accessory genes that were first acquired and then stayed as the plasmid diverged. Our study increases the available collection of complete genome sequences of BHR plasmids, and since pSFA231 is the only characterized PromA plasmid from China, our findings also enhance our understanding of the genetic diversity of this plasmid group in different parts of the world.

The broad-host-range plasmid pSFA231 isolated from petroleum-contaminated sediment represents a new member of the PromA plasmid family

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Xiaobin eLi

2015-01-01

Full Text Available A self-transmissible broad-host-range (BHR plasmid pSFA231 was isolated from petroleum-contaminated sediment in Shen-fu wastewater irrigation zone, China, using the triparental mating exogenous plasmid capture method. Based on its complete sequence the plasmid has a size of 41.5 kb and codes for 50 putative open reading frames (orfs, 28 of which represent genes involved in replication, partitioning and transfer functions of the plasmid. Phylogenetic analysis grouped pSFA231 into the newly defined PromA plasmid family, which currently includes five members. Further comparative genomic analysis shows that pSFA231 shares the common backbone regions with the other PromA plasmids, i.e., genes involved in replication, maintenance and control, and conjugative transfer. Nevertheless, phylogenetic divergence was found in specific gene products. We propose to divide the PromA group into two subgroups, PromA-α (pMRAD02, pSB102 and PromA-β (pMOL98, pIPO2T, pSFA231, pTer331, based on the splits network analysis of the RepA protein. Interestingly, a cluster of hypothetical orfs located between parA and traA of pSFA231 shows high similarity with the corresponding regions on pMOL98, pIPO2T and pTer331, suggesting these hypothetical orfs may represent ‘‘essential’’ plasmid backbone genes for the PromA-β subgroup. Alternatively, they may also be accessory genes that were first acquired and then stayed as the plasmid diverged. Our study increases the available collection of complete genome sequences of BHR plasmids, and since pSFA231 is the only characterized PromA plasmid from China, our findings also enhance our understanding of the genetic diversity of this plasmid group in different parts of the world.

Multifocal Aeromonas Osteomyelitis in a Child with Leukemia

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Dimitrios Doganis

2016-01-01

Full Text Available Aeromonas hydrophila is a Gram negative organism causing both intestinal and extraintestinal disease. The case of a 14-year-old girl with underlying immunodeficiency and leukemia who developed systemic A. hydrophila infection is described in this report. While in deep bone marrow aplasia she developed fever, severe pain in the lower extremities, and swelling of the left femur. Blood culture showed Escherichia coli and A. hydrophila whereas pus culture from the soft tissue swelling showed the presence of A. hydrophila. Imaging studies showed diffuse osteolytic lesions. Patient received 5 months of intravenous and oral antibiotics and she improved clinically whereas the radiology findings persisted.

Detection and quantification of Aeromonas salmonicida in fish tissue by real-time PCR

DEFF Research Database (Denmark)

Bartkova, Simona; Kokotovic, Branco; Skall, H. F.

2017-01-01

Furunculosis, a septicaemic infection caused by the bacterium Aeromonas salmonicida subsp. salmonicida, currently causes problems in Danish seawater rainbow trout production. Detection has mainly been achieved by bacterial culture, but more rapid and sensitive methods are needed. A previously...

Plasmids foster diversification and adaptation of bacterial populations in soil.

Science.gov (United States)

Heuer, Holger; Smalla, Kornelia

2012-11-01

It is increasingly being recognized that the transfer of conjugative plasmids across species boundaries plays a vital role in the adaptability of bacterial populations in soil. There are specific driving forces and constraints of plasmid transfer within bacterial communities in soils. Plasmid-mediated genetic variation allows bacteria to respond rapidly with adaptive responses to challenges such as irregular antibiotic or metal concentrations, or opportunities such as the utilization of xenobiotic compounds. Cultivation-independent detection and capture of plasmids from soil bacteria, and complete sequencing have provided new insights into the role and ecology of plasmids. Broad host range plasmids such as those belonging to IncP-1 transfer a wealth of accessory functions which are carried by similar plasmid backbones. Plasmids with a narrower host range can be more specifically adapted to particular species and often transfer genes which complement chromosomally encoded functions. Plasmids seem to be an ancient and successful strategy to ensure survival of a soil population in spatial and temporal heterogeneous conditions with various environmental stresses or opportunities that occur irregularly or as a novel challenge in soil. © 2012 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

Producción de ácido indol-3-acético por Pseudomonas veronii R4 y formación de raíces en hojas de vid “Thompson seedless” in vitro

OpenAIRE

Maria Peñafiel Jaramillo; Alexandra Elizabeth Barrera Álvarez; Emma Danielly Torres Navarrete; Hayron Fabricio Canchignia Martínez; Humberto Prieto-Encalada; Jaime Morante Carriel

2016-01-01

Rizobacterias con actividad antagonista son empleadas a problemas patológicos y promueven el desarrollo de tejido radicular de especies vegetales El objetivo del estudio fue evaluar la capacidad en síntesis de ácido indol-3-acetico (AIA) y la formación de raíces en hojas de vid “Thompson Seedless”, por el empleo de Pseudomonas veronii R4 in vitro. La bacteria, fue incubada en medio mínimo M9 y se verificó la producción de AIA a 24, 48 y 72 h de muestreo, los sobrenadantes fueron analizandos p...

Antibiotic resistance profiling and phenotyping of Aeromonas species isolated from aquatic sources

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Olumide A. Odeyemi

2017-01-01

Full Text Available This study aimed to investigate antibiotics resistance pattern and phenotyping of Aeromonas species isolated from different aquatic sources in Melaka, Malaysia. A total of 53 Aeromonas species were isolated from the following sources: sediment (n = 13, bivalve (n = 10, sea cucumber (n = 16 and sea water (n = 14 and resistance to 12 antibiotics – Tetracycline (30 μg, Kanamycin (30 μg, Oxytetracycline (30 μg, Ampicillin (10 μg, Streptomycin (10 μg, Gentamicin (10 μg, Sulphamethoxazole (25 μg, Nalixidic acid (30 μg, Trimethoprim (1.25 μg, Novobiocin (5 μg, Penicilin (10 μg and Chloramphenicol (10 μg was tested. The results obtained from this study reveal multi drug resistance pattern among the isolates. All the isolates were completely resistant to Ampicillin, Novobiocin, Sulphamethoxazole and Trimethoprim, respectively but susceptible to Tetracycline (100%, Kanamycin (5.7%, Gentamicin (5.7% and Oxytetracycline (24.5%. Antibiotics phenotyping of the bacteria revealed 21 different phenotypes among the isolates.

Mutation in ESBL Plasmid from Escherichia coli O104:H4 Leads Autoagglutination and Enhanced Plasmid Dissemination

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Mickaël Poidevin

2018-02-01

Full Text Available Conjugative plasmids are one of the main driving force of wide-spreading of multidrug resistance (MDR bacteria. They are self-transmittable via conjugation as carrying the required set of genes and cis-acting DNA locus for direct cell-to-cell transfer. IncI incompatibility plasmids are nowadays often associated with extended-spectrum beta-lactamases producing Enterobacteria in clinic and environment. pESBL-EA11 was isolated from Escherichia coli O104:H4 outbreak strain in Germany in 2011. During the previous study identifying transfer genes of pESBL-EA11, it was shown that transposon insertion at certain DNA region of the plasmid, referred to as Hft, resulted in great enhancement of transfer ability. This suggested that genetic modifications can enhance dissemination of MDR plasmids. Such ‘superspreader’ mutations have attracted little attention so far despite their high potential to worsen MDR spreading. Present study aimed to gain our understanding on regulatory elements that involved pESBL transfer. While previous studies of IncI plasmids indicated that immediate downstream gene of Hft, traA, is not essential for conjugative transfer, here we showed that overexpression of TraA in host cell elevated transfer rate of pESBL-EA11. Transposon insertion or certain nucleotide substitutions in Hft led strong TraA overexpression which resulted in activation of essential regulator TraB and likely overexpression of conjugative pili. Atmospheric Scanning Electron Microscopy observation suggested that IncI pili are distinct from other types of conjugative pili (such as long filamentous F-type pili and rather expressed throughout the cell surface. High transfer efficiency in the mutant pESBL-EA11 was involved with hyperpiliation which facilitates cell-to-cell adhesion, including autoagglutination. The capability of plasmids to evolve to highly transmissible mutant is alarming, particularly it might also have adverse effect on host pathogenicity.

Aeromonas hydrophila as cause of hemorrhagic septicemia in a ground-hornbill (Bucorvus abyssinicus).

Science.gov (United States)

Ocholi, R A; Kalejaiye, J O

1990-01-01

An acute hemorrhagic septicemia in a captive ground-hornbill (Bucorvus abyssinicus) is reported. Aeromonas hydrophila was isolated from lungs, liver, kidney, and intestines. Postmortem lesions were characterized by hemorrhages in the internal organs. Microscopically, necrotic lesions were found in the liver, lungs, and kidney. Factors that might have contributed to the clinical disease condition are discussed.

THE PREVALENCE OF Salmonella sp., Listeria sp. AND Aeromonas spp. IN CATFISH (CLARIAS (Clarias gariepinus AND TILAPIA (Tilapia mossambica BY PELLETING METHOD

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Titik Budiati

2013-06-01

Full Text Available The aim of this study was to modify the isolation methods of Aeromonas sp., Salmonella spp., and Listeria sp. in catfish (Clarias gariepinus and tilapia (Tilapia mossambica obtained from wet markets and ponds in Malaysia by pelleting the sample. A total of 108 samples (32 catfish intestines, 32 tilapia intestines, and 44 water samples were obtained from nine wet markets and eight ponds. The modified method was employed by pelleting the samples and followed by either implementing pre-enrichment or without pre-enrichment on the isolation of Salmonella and Listeria spp. The modified method (by pelleting the sample in combination with pre-enrichment was the most efficient for Salmonella and Listeria isolation. The sensitivity of the modified Salmonella isolation method was 0.53 and 0.73 for fish and water samples, respectively. The sensitivity of the modified Listeria method was 1 and 0.92 for fish and water samples, respectively. However, the sensitivity of the method by pelleting the sample was similar to those of non-pelleting the sample on Aeromonas isolation. Five species of Aeromonas spp., seven serovars of Salmonella sp., and four species of Listeria sp. were observed in catfish, tilapia and water samples. Overall, by pelleting the sample offered the beneficial to isolate Aeromonas spp., Salmonella sp. and Listeria spp. in catfish, tilapia and water.

Plasmid-associated sensitivity of Bacillus thuringiensis to UV light

International Nuclear Information System (INIS)

Benoit, T.G.; Wilson, G.R.; Bull, D.L.; Aronson, A.I.

1990-01-01

Spores and vegetative cells of Bacillus thuringiensis were more sensitive to UV light than were spores or cells of plasmid-cured B. thuringiensis strains or of the closely related Bacillus cereus. Introduction of B. thuringiensis plasmids into B. cereus by cell mating increased the UV sensitivity of the cells and spores. Protoxins encoded by one or more B. thuringiensis plasmids were not involved in spore sensitivity, since a B. thuringiensis strain conditional for protoxin accumulation was equally sensitive at the permissive and nonpermissive temperatures. In addition, introduction of either a cloned protoxin gene, the cloning vector, or another plasmid not containing a protoxin gene into a plasmid-cured strain of B. thuringiensis all increased the UV sensitivity of the spores. Although the variety of small, acid-soluble proteins was the same in the spores of all strains examined, the quantity of dipicolinic acid was about twice as high in the plasmid-containing strains, and this may account for the differences in UV sensitivity of the spores. The cells of some strains harboring only B. thuringiensis plasmids were much more sensitive than cells of any of the other strains, and the differences were much greater than observed with spores

Diarrea del viajero asociada a Aeromonas hydrophila Traveller's diarrohea caused by Aeromonas hydrophila

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M. L. Pita Toledo

2001-06-01

Full Text Available Aeromonas hydrophila es una bacteria que se encuentra frecuentemente en aguas dulces y salobres. Desde hace varios años se conoce que determinadas cepas de la especie pueden causar enfermedad en pescados y en anfibios, existiendo cierta controversia sobre su patogeneicidad en humanos. No obstante, puede dar lugar a infección en personas, que la adquieren bien a través de heridas abiertas o bien por ingestión de alimentos o agua contaminados. Sin embargo, en prácticamente la totalidad de las publicaciones se hace referencia a casos aislados más que a brotes producidos por esta bacteria. Generalmente la infección por A. hydrophila da lugar a gastroenteritis en personas sanas, pudiendo generar una septicemia en individuos inmunodeprimidos.En 1998 se produjo una alarma en el sector hotelero por un incremento considerable de los casos de gastroenteritis entre los turistas que acudían durante sus vacaciones a determinadas zonas costeras de la isla de Tenerife.Tras tener conocimiento de la situación, la Dirección General de Salud Pública inició una investigación epidemiológica con el objetivo de conocer la magnitud real del problema detectado e identificar los factores asociados a la misma, para poner en marcha las medidas correctoras y de control necesarias. El análisis inicial permitió determinar que se trataba de un proceso de gran magnitud en su extensión aunque de carácter leve, que afectaba únicamente a los turistas en una zona costera en concreto, compatible por lo tanto con la diarrea del viajero, planteándose un origen probablemente hídrico.Aeromonas hydrophila is a bacteria frequently found in fresh water and saline water. Certain strains of the species have been known to cause disease in fish and amphibians for several years, although some controversy exists about its ability to cause illness in humans. Nevertheless, either through open wounds or contaminated food or water, it can give rise to infection. However, almost

Plasmid-Mediated Antimicrobial Resistance in Staphylococci and Other Firmicutes.

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Schwarz, Stefan; Shen, Jianzhong; Wendlandt, Sarah; Fessler, Andrea T; Wang, Yang; Kadlec, Kristina; Wu, Cong-Ming

2014-12-01

In staphylococci and other Firmicutes, resistance to numerous classes of antimicrobial agents, which are commonly used in human and veterinary medicine, is mediated by genes that are associated with mobile genetic elements. The gene products of some of these antimicrobial resistance genes confer resistance to only specific members of a certain class of antimicrobial agents, whereas others confer resistance to the entire class or even to members of different classes of antimicrobial agents. The resistance mechanisms specified by the resistance genes fall into any of three major categories: active efflux, enzymatic inactivation, and modification/replacement/protection of the target sites of the antimicrobial agents. Among the mobile genetic elements that carry such resistance genes, plasmids play an important role as carriers of primarily plasmid-borne resistance genes, but also as vectors for nonconjugative and conjugative transposons that harbor resistance genes. Plasmids can be exchanged by horizontal gene transfer between members of the same species but also between bacteria belonging to different species and genera. Plasmids are highly flexible elements, and various mechanisms exist by which plasmids can recombine, form cointegrates, or become integrated in part or in toto into the chromosomal DNA or into other plasmids. As such, plasmids play a key role in the dissemination of antimicrobial resistance genes within the gene pool to which staphylococci and other Firmicutes have access. This chapter is intended to provide an overview of the current knowledge of plasmid-mediated antimicrobial resistance in staphylococci and other Firmicutes.

Microplastics as a vector for the transport of the bacterial fish pathogen species Aeromonas salmonicida.

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Viršek, Manca Kovač; Lovšin, Marija Nika; Koren, Špela; Kržan, Andrej; Peterlin, Monika

2017-12-15

Microplastics is widespread in the marine environment where it can cause numerous negative effects. It can provide space for the growth of organisms and serves as a vector for the long distance transfer of marine microorganisms. In this study, we examined the sea surface concentrations of microplastics in the North Adriatic and characterized bacterial communities living on the microplastics. DNA from microplastics particles was isolated by three different methods, followed by PCR amplification of 16S rDNA, clone libraries preparation and phylogenetic analysis. 28 bacterial species were identified on the microplastics particles including Aeromonas spp. and hydrocarbon-degrading bacterial species. Based on the 16S rDNA sequences the pathogenic fish bacteria Aeromonas salmonicida was identified for the first time on microplastics. Because A. salmonicida is responsible for illnesses in fish, it is crucial to get answers if and how microplastics pollution is responsible for spreading of diseases. Copyright © 2017 Elsevier Ltd. All rights reserved.

Frequency and diversity of small cryptic plasmids in the genus Rahnella

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Summers David K

2010-02-01

Full Text Available Abstract Background Rahnella is a widely distributed genus belonging to the Enterobacteriaceae and frequently present on vegetables. Although Rahnella has interesting agro-economical and industrial properties and several strains possess antibiotic resistances and toxin genes which might spread within microbial communities, little is known about plasmids of this genus. Thus, we isolated a number of Rahnella strains and investigated their complements of small plasmids. Results In total 53 strains were investigated and 11 plasmids observed. Seven belonged to the ColE1 family; one was ColE2-like and three shared homology to rolling circle plasmids. One of them belonged to the pC194/pUB110 family and two showed similarity to poorly characterised plasmid groups. The G+C content of two rolling circle plasmids deviated considerably from that of Rahnella, indicating that their usual hosts might belong to other genera. Most ColE1-like plasmids formed a subgroup within the ColE1 family that seems to be fairly specific for Rahnella. Intriguingly, the multimer resolution sites of all ColE1-like plasmids had the same orientation with respect to the origin of replication. This arrangement might be necessary to prevent inappropriate synthesis of a small regulatory RNA that regulates cell division. Although the ColE1-like plasmids did not possess any mobilisation system, they shared large parts with high sequence identity in coding and non-coding regions. In addition, highly homologous regions of plasmids isolated from Rahnella and the chromosomes of Erwinia tasmaniensis and Photorhabdus luminescens could be identified. Conclusions For the genus Rahnella we observed plasmid-containing isolates at a frequency of 19%, which is in the average range for Enterobacteriaceae. These plasmids belonged to diffent groups with members of the ColE1-family most frequently found. Regions of striking sequence homology of plasmids and bacterial chromosomes highlight the

Plasmid mediated enhancement of uv resistance in Streptococcus faecalis

International Nuclear Information System (INIS)

Miehl, R.; Miller, M.; Yasbin, R.E.

1980-01-01

A 38.5-Mdal plasmid of Streptococcus faecalis subdp. zymogenes has been shown to enhance survival following uv irradiation. In addition, the presence of this plasmid increases the mutation frequencies following uv irradiation and enhanced W-reactivation. The data presented indicate that S. faecalis has an inducible error-prone repair system and that the plasmid enhances these repair functions

A foodborne outbreak of Aeromonas hydrophila in a college, Xingyi City, Guizhou, China, 2012.

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Zhang, Qian; Shi, Guo-Qing; Tang, Guang-Peng; Zou, Zhi-Tin; Yao, Guang-Hai; Zeng, Guang

2012-10-01

On 12 May 2012, over 200 college students with acute diarrhoea were reported to the Guizhou Center for Disease Control and Prevention. We conducted an investigation to identify the agent and mode of transmission and to recommend control measures. A suspected case was a person at the college with onset of ≥ two of the following symptoms: diarrhoea (more than three loose stools in 24 hours), abdominal pain, vomiting or fever (> 37.5C) between 6 and 15 May 2012. A confirmed case also had a positive Aeromonas hydrophila culture from a stool sample. A retrospective-cohort study of 902 students compared attack rates (AR) by dining place, meals and food history. We reviewed the implicated premise, its processes and preparation of implicated food. We identified 349 suspected cases (AR = 14%) and isolated Aeromonas hydrophila from three stools of 15 cases. Students who ate in cafeteria A were more likely to be ill compared to those eating in other places (relative risk [RR]: 3.1, 95% confidence interval [CI]: 2.0-4.8). The cohort study implicated cold cucumber (RR: 2.6, 95% CI: 2.0-3.3) and houttuynia dishes (RR: 1.8, 95% CI: 1.4-2.3). Environmental investigation showed that vegetables were washed in polluted water from a tank close to the sewage ditch, then left at 30 °C for two hours before serving. The Escherichia coli count of the tank was well above the standard for drinking-water. This outbreak of Aeromonas hydrophila was most probably caused by salad ingredients washed in contaminated tank water. We recommended enhancing training of foodhandlers, ensuring tanks and sewerage systems comply with appropriate standards and adequate monitoring of drinking-water sources.

Functional genomic characterization of virulence factors from necrotizing fasciitis-causing strains of Aeromonas hydrophila.

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Grim, Christopher J; Kozlova, Elena V; Ponnusamy, Duraisamy; Fitts, Eric C; Sha, Jian; Kirtley, Michelle L; van Lier, Christina J; Tiner, Bethany L; Erova, Tatiana E; Joseph, Sandeep J; Read, Timothy D; Shak, Joshua R; Joseph, Sam W; Singletary, Ed; Felland, Tracy; Baze, Wallace B; Horneman, Amy J; Chopra, Ashok K

2014-07-01

The genomes of 10 Aeromonas isolates identified and designated Aeromonas hydrophila WI, Riv3, and NF1 to NF4; A. dhakensis SSU; A. jandaei Riv2; and A. caviae NM22 and NM33 were sequenced and annotated. Isolates NF1 to NF4 were from a patient with necrotizing fasciitis (NF). Two environmental isolates (Riv2 and -3) were from the river water from which the NF patient acquired the infection. While isolates NF2 to NF4 were clonal, NF1 was genetically distinct. Outside the conserved core genomes of these 10 isolates, several unique genomic features were identified. The most virulent strains possessed one of the following four virulence factors or a combination of them: cytotoxic enterotoxin, exotoxin A, and type 3 and 6 secretion system effectors AexU and Hcp. In a septicemic-mouse model, SSU, NF1, and Riv2 were the most virulent, while NF2 was moderately virulent. These data correlated with high motility and biofilm formation by the former three isolates. Conversely, in a mouse model of intramuscular infection, NF2 was much more virulent than NF1. Isolates NF2, SSU, and Riv2 disseminated in high numbers from the muscular tissue to the visceral organs of mice, while NF1 reached the liver and spleen in relatively lower numbers on the basis of colony counting and tracking of bioluminescent strains in real time by in vivo imaging. Histopathologically, degeneration of myofibers with significant infiltration of polymorphonuclear cells due to the highly virulent strains was noted. Functional genomic analysis provided data that allowed us to correlate the highly infectious nature of Aeromonas pathotypes belonging to several different species with virulence signatures and their potential ability to cause NF. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

A foodborne outbreak of Aeromonas hydrophila in a college, Xingyi City, Guizhou, China, 2012

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Guang Zeng

2012-12-01

Full Text Available Background: On 12 May 2012, over 200 college students with acute diarrhoea were reported to the Guizhou Center for Disease Control and Prevention. We conducted an investigation to identify the agent and mode of transmission and to recommend control measures.Methods: A suspected case was a person at the college with onset of more than two of the following symptoms: diarrhoea (more than three loose stools in 24 hours, abdominal pain, vomiting or fever (> 37.5C between 6 and 15 May 2012. A confirmed case also had a positive Aeromonas hydrophila culture from a stool sample. A retrospective-cohort study of 902 students compared attack rates (AR by dining place, meals and food history. We reviewed the implicated premise, its processes and preparation of implicated food.Results: We identified 349 suspected cases (AR = 14% and isolated Aeromonas hydrophila from three stools of 15 cases. Students who ate in cafeteria A were more likely to be ill compared to those eating in other places (relative risk [RR]: 3.1, 95% confidence interval [CI]: 2.0–4.8. The cohort study implicated cold cucumber (RR: 2.6, 95% CI: 2.0–3.3 and houttuynia dishes (RR: 1.8, 95% CI: 1.4–2.3. Environmental investigation showed that vegetables were washed in polluted water from a tank close to the sewage ditch, then left at 30°C for two hours before serving. The Escherichia coli count of the tank was well above the standard for drinking water.Conclusion: This outbreak of Aeromonas hydrophila was most probably caused by salad ingredients washed in contaminated tank water. We recommended enhancing training of foodhandlers, ensuring tanks and sewerage systems comply with appropriate standards and adequate monitoring of drinking water sources.

Multiple drug resistant carbapenemases producing Acinetobacter baumannii isolates harbours multiple R-plasmids

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Rajagopalan Saranathan

2014-01-01

Full Text Available Background & objectives: The nosocomial human pathogen Acinetobacter baumannii has high propensity to develop resistance to antimicrobials and to become multidrug resistant (MDR, consequently complicating the treatment. This study was carried out to investigate the presence of resistant plasmids (R-plasmids among the clinical isolates of A. baumannii. In addition, the study was performed to check the presence of common β-lactamases encoding genes on these plasmids. Methods: A total of 55 clinical isolates of A. baumannii were included in the study and all were subjected to plasmid DNA isolation, followed by PCR to check the presence of resistance gene determinants such as blaOXA-23 , blaOXA-51, blaOXA-58 and blaIMP-1 on these plasmids that encode for oxacillinase (OXA and metallo-β-lactamase (MBL type of carbapenemases. Plasmid curing experiments were carried out on selected isolates using ethidium bromide and acridine orange as curing agents and the antibiotic resistance profiles were evaluated before and after curing. Results: All the isolates were identified as A. baumannii by 16SrDNA amplification and sequencing. Plasmid DNA isolated from these isolates showed the occurrence of multiple plasmids with size ranging from 500bp to ≥ 25 kb. The percentage of blaOXA-51 and blaOXA-23 on plasmids were found to be 78 and 42 per cent, respectively and 20 isolates (36% carried blaIMP-1 gene on plasmids. Significant difference was observed in the antibiograms of plasmid cured isolates when compared to their parental ones. The clinical isolates became susceptible to more than two antibiotic classes after curing of plasmids indicating plasmid borne resistance. Interpretation & conclusions: Our study determined the plasmid mediated resistance mechanisms and occurrence of different resistance genes on various plasmids isolated from MDR A. baumannii. The present findings showed the evidence for antibiotic resistance mediated through multiple plasmids in

Movement and equipositioning of plasmids by ParA filament disassembly

DEFF Research Database (Denmark)

Ringgaard, Simon; van Zon, Jeroen; Howard, Martin

2009-01-01

, plasmids consistently migrate behind disassembling ParA cytoskeletal structures, suggesting that ParA filaments pull plasmids by depolymerization. The perpetual cycles of ParA assembly and disassembly result in continuous relocation of plasmids, which, on time averaging, results in equidistribution...

Restriction Fragment Length Polymorphisms of Virulence Plasmids in Rhodococcus equi

Science.gov (United States)

Takai, Shinji; Shoda, Masato; Sasaki, Yukako; Tsubaki, Shiro; Fortier, Guillaume; Pronost, Stephane; Rahal, Karim; Becu, Teotimo; Begg, Angela; Browning, Glenn; Nicholson, Vivian M.; Prescott, John F.

1999-01-01

Virulent Rhodococcus equi, which is a well-known cause of pyogranulomatous pneumonia in foals, possesses a large plasmid encoding virulence-associated 15- to 17-kDa antigens. Foal and soil isolates from five countries—Argentina, Australia, Canada, France, and Japan—were investigated for the presence of 15- to 17-kDa antigens by colony blotting, using the monoclonal antibody 10G5, and the gene coding for 15- to 17-kDa antigens by PCR. Plasmid DNAs extracted from positive isolates were digested with restriction endonucleases BamHI, EcoRI, EcoT22I, and HindIII, and the digestion patterns that resulted divided the plasmids of virulent isolates into five closely related types. Three of the five types had already been reported in Canadian and Japanese isolates, and the two new types had been found in French and Japanese isolates. Therefore, we tentatively designated these five types 85-kb type I (pREAT701), 85-kb type II (a new type), 87-kb type I (EcoRI and BamHI type 2 [V. M. Nicholson and J. F. Prescott, J. Clin. Microbiol. 35:738–740, 1997]), 87-kb type II (a new type), and 90-kb (pREL1) plasmids. The 85-kb type I plasmid was found in isolates from Argentina, Australia, Canada, and France. Plasmid 87-kb type I was isolated in specimens from Argentina, Canada, and France. The 85-kb type II plasmid appeared in isolates from France. On the other hand, plasmids 87-kb type II and 90-kb were found only in isolates from Japan. These results revealed geographic differences in the distribution of the virulence plasmids found in the five countries and suggested that the restriction fragment length polymorphism of virulence plasmids might be useful to elucidate the molecular epidemiology of virulent R. equi in the world. PMID:10488224

Plasmid DNA Delivery: Nanotopography Matters.

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Song, Hao; Yu, Meihua; Lu, Yao; Gu, Zhengying; Yang, Yannan; Zhang, Min; Fu, Jianye; Yu, Chengzhong

2017-12-20

Plasmid DNA molecules with unique loop structures have widespread bioapplications, in many cases relying heavily on delivery vehicles to introduce them into cells and achieve their functions. Herein, we demonstrate that control over delicate nanotopography of silica nanoparticles as plasmid DNA vectors has significant impact on the transfection efficacy. For silica nanoparticles with rambutan-, raspberry-, and flower-like morphologies composed of spike-, hemisphere-, and bowl-type subunit nanotopographies, respectively, the rambutan-like nanoparticles with spiky surfaces demonstrate the highest plasmid DNA binding capability and transfection efficacy of 88%, higher than those reported for silica-based nanovectors. Moreover, it is shown that the surface spikes of rambutan nanoparticles provide a continuous open space to bind DNA chains via multivalent interactions and protect the gene molecules sheltered in the spiky layer against nuclease degradation, exhibiting no significant transfection decay. This unique protection feature is in great contrast to a commercial transfection agent with similar transfection performance but poor protection capability against enzymatic cleavage. Our study provides new understandings in the rational design of nonviral vectors for efficient gene delivery.

Multilocus genetics to reconstruct aeromonad evolution

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Roger Frédéric

2012-04-01

Full Text Available Abstract Background Aeromonas spp. are versatile bacteria that exhibit a wide variety of lifestyles. In an attempt to improve the understanding of human aeromonosis, we investigated whether clinical isolates displayed specific characteristics in terms of genetic diversity, population structure and mode of evolution among Aeromonas spp. A collection of 195 Aeromonas isolates from human, animal and environmental sources was therefore genotyped using multilocus sequence analysis (MLSA based on the dnaK, gltA, gyrB, radA, rpoB, tsf and zipA genes. Results The MLSA showed a high level of genetic diversity among the population, and multilocus-based phylogenetic analysis (MLPA revealed 3 major clades: the A. veronii, A. hydrophila and A. caviae clades, among the eleven clades detected. Lower genetic diversity was observed within the A. caviae clade as well as among clinical isolates compared to environmental isolates. Clonal complexes, each of which included a limited number of strains, mainly corresponded to host-associated subsclusters of strains, i.e., a fish-associated subset within A. salmonicida and 11 human-associated subsets, 9 of which included only disease-associated strains. The population structure was shown to be clonal, with modes of evolution that involved mutations in general and recombination events locally. Recombination was detected in 5 genes in the MLSA scheme and concerned approximately 50% of the STs. Therefore, these recombination events could explain the observed phylogenetic incongruities and low robustness. However, the MLPA globally confirmed the current systematics of the genus Aeromonas. Conclusions Evolution in the genus Aeromonas has resulted in exceptionally high genetic diversity. Emerging from this diversity, subsets of strains appeared to be host adapted and/or “disease specialized” while the A. caviae clade displayed an atypical tempo of evolution among aeromonads. Considering that A. salmonicida has been

DNA sequence analysis of plasmids from multidrug resistant Salmonella enterica serotype Heidelberg isolates.

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Jing Han

Full Text Available Salmonella enterica serovar Heidelberg is among the most detected serovars in swine and poultry, ranks among the top five serotypes associated with human salmonellosis and is disproportionately associated with invasive infections and mortality in humans. Salmonella are known to carry plasmids associated with antimicrobial resistance and virulence. To identify plasmid-associated genes in multidrug resistant S. enterica serovar Heidelberg, antimicrobial resistance plasmids from five isolates were sequenced using the 454 LifeSciences pyrosequencing technology. Four of the isolates contained incompatibility group (Inc A/C multidrug resistance plasmids harboring at least eight antimicrobial resistance genes. Each of these strains also carried a second resistance plasmid including two IncFIB, an IncHI2 and a plasmid lacking an identified Inc group. The fifth isolate contained an IncI1 plasmid, encoding resistance to gentamicin, streptomycin and sulfonamides. Some of the IncA/C plasmids lacked the full concert of transfer genes and yet were able to be conjugally transferred, likely due to the transfer genes carried on the companion plasmids in the strains. Several non-IncA/C resistance plasmids also carried putative virulence genes. When the sequences were compared to previously sequenced plasmids, it was found that while all plasmids demonstrated some similarity to other plasmids, they were unique, often due to differences in mobile genetic elements in the plasmids. Our study suggests that Salmonella Heidelberg isolates harbor plasmids that co-select for antimicrobial resistance and virulence, along with genes that can mediate the transfer of plasmids within and among other bacterial isolates. Prevalence of such plasmids can complicate efforts to control the spread of S. enterica serovar Heidelberg in food animal and human populations.

Simple method for identification of plasmid-coded proteins

International Nuclear Information System (INIS)

Sancar, A.; Hack, A.M.; Rupp, W.D.

1979-01-01

Proteins encoded by plasmid DNA are specifically labeled in uv-irradiated cells of Escherichia coli carrying recA and uvrA mutations because extensive degradation of the chromosome DNA occurs concurrently with amplification of plasmid DNA

Presence and analysis of plasmids in human and animal associated arcobacter species.

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Laid Douidah

Full Text Available In this study, we report the screening of four Arcobacter species for the presence of small and large plasmids. Plasmids were present in 9.9% of the 273 examined strains. One Arcobacter cryaerophilus and four Arcobacter butzleri plasmids were selected for further sequencing. The size of three small plasmids isolated from A. butzleri and the one from A. cryaerophilus strains ranged between 4.8 and 5.1 kb, and the size of the large plasmid, isolated from A. butzleri, was 27.4 kbp. The G+C content of all plasmids ranged between 25.4% and 26.2%. A total of 95% of the large plasmid sequence represents coding information, which contrasts to the 20 to 30% for the small plasmids. Some of the open reading frames showed a high homology to putative conserved domains found in other related organisms, such as replication, mobilization and genes involved in type IV secretion system. The large plasmid carried 35 coding sequences, including seven genes in a contiguous region of 11.6 kbp that encodes an orthologous type IV secretion system found in the Wolinella succinogenes genome, Helicobacter pylori and Campylobacter jejuni plasmids, which makes this plasmid interesting for further exploration.

Application of methylation in improving plasmid transformation into Helicobacter pylori.

Science.gov (United States)

Zhao, Huilin; Xu, Linlin; Rong, Qianyu; Xu, Zheng; Ding, Yunfei; Zhang, Ying; Wu, Yulong; Li, Boqing; Ji, Xiaofei

2018-05-23

Helicobacter pylori is an important gastrointestinal pathogen. Its strains possess different levels of powerful restriction modification systems, which are significant barriers to genetic tools used for studying the role of functional genes in its pathogenesis. Methylating vectors in vitro was reported as an alternative to overcome this barrier in several bacteria. In this study we used two H. pylori-E. coli shuttle plasmids and several single/double-crossover homologous recombination gene-targeting plasmids, to test the role of methylation in H. pylori transformation. According to our results, transformants could be obtained only after shuttle plasmids were methylated before transformation. It is helpful in gene complementation and over-expression although at a low frequency. The frequency of gene-targeting transformation was also increased after methylation, especially for the single-crossover recombination plasmids, the transformants of which could only be obtained after methylation. For the double-crossover recombination targeting plasmids, the initial yield of transformants was 0.3-0.8 × 10 2 CFUs per microgram plasmid DNA. With the help of methylation, the yield was increased to 0.4-1.3 × 10 2 CFUs per microgram plasmid DNA. These results suggest that in vitro methylation can improve H. pylori transformation by different plasmids, which will benefit the pathogenic mechanism research. Copyright © 2018. Published by Elsevier B.V.

Plasmid marker rescue transformation proceeds by breakage-reunion in Bacillus subtilis

International Nuclear Information System (INIS)

Weinrauch, Y.; Dubnau, D.

1987-01-01

Bacillus subtilis carrying a plasmid which replicates with a copy number of about 1 was transformed with linearized homologous plasmid DNA labeled with the heavy isotopes 2 H and 15 N, in the presence of 32 Pi and 6-(p-hydroxyphenylazo)-uracil to inhibit DNA replication. Plasmid DNA was isolated from the transformed culture and fractionated in cesium chloride density gradients. The distribution of total and donor plasmid DNA was examined, using specific hybridization probes. The synthesis of new DNA, associated with the integration of donor moiety, was also monitored. Donor-specific sequences were present at a density intermediate between that of light and hybrid DNA. This recombinant DNA represented 1.4% of total plasmid DNA. The latter value corresponded well with the transforming activity (1.7%) obtained for the donor marker. Newly synthesized material associated with plasmid DNA at the recombinant density amounted to a minor portion of the recombinant plasmid DNA. These data suggest that, like chromosomal transformation, plasmid marker rescue transformation does not require replication for the integration of donor markers and, also like chromosomal transformation, proceeds by a breakage-reunion mechanism. The extent of donor DNA replacement of recipient DNA per plasmid molecule of 54 kilobases (27 kilobase pairs) was estimated as 16 kilobases

THE ENDOGENOUS BACILLUS-SUBTILIS (NATTO) PLASMIDS PTA1015 AND PTA1040 CONTAIN SIGNAL PEPTIDASE-ENCODING GENES - IDENTIFICATION OF A NEW STRUCTURAL MODULE ON CRYPTIC PLASMIDS

NARCIS (Netherlands)

MEIJER, WJJ; DEJONG, A; BEA, G; WISMAN, A; TJALSMA, H; VENEMA, G; BRON, S; MAARTEN, J; VANDIJL, JM

Various strains of Bacillus subtilis (natto) contain small cryptic plasmids that replicate via the rolling-circle mechanism. Like plasmids from other Gram-positive bacteria, these plasmids are composed of several distinct structural modules. A new structural module was identified on the B. subtilis

Investigation of diversity of plasmids carrying the blaTEM-52 gene

DEFF Research Database (Denmark)

Bielak, Eliza Maria; Bergenholtz, Rikke D.; Jørgensen, Mikael Skaanning

2011-01-01

OBJECTIVES: To investigate the diversity of plasmids that carry blaTEM-52 genes among Escherichia coli and Salmonella enterica originating from animals, meat products and humans. METHODS: A collection of 22 blaTEM-52-encoding plasmids was characterized by restriction fragment length polymorphism...... of self-transfer to a plasmid-free E. coli recipient. CONCLUSIONS: The blaTEM-52 gene found in humans could have been transmitted on transferable plasmids originating from animal sources. Some of the blaTEM-52 plasmids carry replicons that differ from the classical ones. Two novel replicons were detected...

Conjugative plasmid pAW63 brings new insights into the genesis of the Bacillus anthracis virulence plasmid pXO2 and of the Bacillus thuringiensis plasmid pBT9727

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Mahillon Jacques

2005-07-01

Full Text Available Abstract Background Bacillus cereus, Bacillus anthracis and Bacillus thuringiensis belong to the genetically close-knit Bacillus cereus sensu lato group, a family of rod-shaped Gram-positive bacteria. pAW63 is the first conjugative plasmid from the B. cereus group to be completely sequenced. Results The 71,777 bp nucleotide sequence of pAW63 reveals a modular structure, including a 42 kb tra region encoding homologs of the Type IV secretion systems components VirB11, VirB4 and VirD4, as well as homologs of Gram-positive conjugation genes from Enterococcus, Lactococcus, Listeria, Streptococcus and Staphylococcus species. It also firmly establishes the existence of a common backbone between pAW63, pXO2 from Bacillus anthracis and pBT9727 from the pathogenic Bacillus thuringiensis serovar konkukian strain 97-27. The alignment of these three plasmids highlights the presence of well conserved segments, in contrast to distinct regions of high sequence plasticity. The study of their specific differences has provided a three-point reference framework that can be exploited to formulate solid hypotheses concerning the functionalities and the molecular evolution of these three closely related plasmids. This has provided insight into the chronology of their divergence, and led to the discovery of two Type II introns on pAW63, matching copies of the mobile element IS231L in different loci of pXO2 and pBT9727, and the identification on pXO2 of a 37 kb pathogenicity island (PAI containing the anthrax capsule genes. Conclusion The complete sequence determination of pAW63 has led to a functional map of the plasmid yielding insights into its conjugative apparatus, which includes T4SS-like components, as well as its resemblance to other large plasmids of Gram-positive bacteria. Of particular interest is the extensive homology shared between pAW63 and pXO2, the second virulence plasmid of B. anthracis, as well as pBT9727 from the pathogenic strain B. thuringiensis

Permissiveness of soil microbial communities towards broad host range plasmids

DEFF Research Database (Denmark)

Klümper, Uli

. Plasmids are implicated in the rapid spread of antibiotic resistance and the emergence of multi-resistant pathogenic bacteria, making it crucial to be able to quantify, understand, and, ideally, control plasmid transfer in mixed microbial communities. The fate of plasmids in microbial communities...... of microbial communities may be directly interconnected through transfer of BHR plasmids at a so far unrecognized level. The developed method furthermore enabled me to explore how agronomic practices may affect gene transfer in soil microbial communities. I compared bacterial communities extracted from plots...

Drug resistance plasmids in Lactobacillus acidophilus and Lactobacillus reuteri.

OpenAIRE

Vescovo, M; Morelli, L; Bottazzi, V

1982-01-01

Sixteen strains of Lactobacillus reuteri and 20 strains of Lactobacillus acidophilus were tested for resistance to 22 antibiotics by using commercially available sensitivity disks. Evidence suggesting linkage of these resistances to plasmids was obtained by "curing" experiments with acridine dyes and high growth temperatures. Examination of plasmid patterns of agarose gel electrophoresis provided further evidence of loss in plasmid DNA under curing conditions in some of the strains examined.

Plasmid construction using recombination activity in the fission yeast Schizosaccharomyces pombe.

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Ayako Chino

Full Text Available BACKGROUND: Construction of plasmids is crucial in modern genetic manipulation. As of now, the common method for constructing plasmids is to digest specific DNA sequences with restriction enzymes and to ligate the resulting DNA fragments with DNA ligase. Another potent method to construct plasmids, known as gap-repair cloning (GRC, is commonly used in the budding yeast Saccharomyces cerevisiae. GRC makes use of the homologous recombination activity that occurs within the yeast cells. Due to its flexible design and efficiency, GRC has been frequently used for constructing plasmids with complex structures as well as genome-wide plasmid collections. Although there have been reports indicating GRC feasibility in the fission yeast Schizosaccharomyces pombe, this species is not commonly used for GRC as systematic studies of reporting GRC efficiency in S. pombe have not been performed till date. METHODOLOGY/PRINCIPAL FINDINGS: We investigated GRC efficiency in S. pombe in this study. We first showed that GRC was feasible in S. pombe by constructing a plasmid that contained the LEU2 auxotrophic marker gene in vivo and showed sufficient efficiency with short homology sequences (>25 bp. No preference was shown for the sequence length from the cut site in the vector plasmid. We next showed that plasmids could be constructed in a proper way using 3 DNA fragments with 70% efficiency without any specific selections being made. The GRC efficiency with 3 DNA fragments was dramatically increased >95% in lig4Delta mutant cell, where non-homologous end joining is deficient. Following this approach, we successfully constructed plasmid vectors with leu1+, ade6+, his5+, and lys1+ markers with the low-copy stable plasmid pDblet as a backbone by applying GRC in S. pombe. CONCLUSIONS/SIGNIFICANCE: We concluded that GRC was sufficiently feasible in S. pombe for genome-wide gene functional analysis as well as for regular plasmid construction. Plasmids with different

Brownian Ratchet Mechanism for Faithful Segregation of Low-Copy-Number Plasmids.

Science.gov (United States)

Hu, Longhua; Vecchiarelli, Anthony G; Mizuuchi, Kiyoshi; Neuman, Keir C; Liu, Jian

2017-04-11

Bacterial plasmids are extrachromosomal DNA that provides selective advantages for bacterial survival. Plasmid partitioning can be remarkably robust. For high-copy-number plasmids, diffusion ensures that both daughter cells inherit plasmids after cell division. In contrast, most low-copy-number plasmids need to be actively partitioned by a conserved tripartite ParA-type system. ParA is an ATPase that binds to chromosomal DNA; ParB is the stimulator of the ParA ATPase and specifically binds to the plasmid at a centromere-like site, parS. ParB stimulation of the ParA ATPase releases ParA from the bacterial chromosome, after which it takes a long time to reset its DNA-binding affinity. We previously demonstrated in vitro that the ParA system can exploit this biochemical asymmetry for directed cargo transport. Multiple ParA-ParB bonds can bridge a parS-coated cargo to a DNA carpet, and they can work collectively as a Brownian ratchet that directs persistent cargo movement with a ParA-depletion zone trailing behind. By extending this model, we suggest that a similar Brownian ratchet mechanism recapitulates the full range of actively segregated plasmid motilities observed in vivo. We demonstrate that plasmid motility is tuned as the replenishment rate of the ParA-depletion zone progressively increases relative to the cargo speed, evolving from diffusion to pole-to-pole oscillation, local excursions, and, finally, immobility. When the plasmid replicates, the daughters largely display motilities similar to that of their mother, except that when the single-focus progenitor is locally excursive, the daughter foci undergo directed segregation. We show that directed segregation maximizes the fidelity of plasmid partition. Given that local excursion and directed segregation are the most commonly observed modes of plasmid motility in vivo, we suggest that the operation of the ParA-type partition system has been shaped by evolution for high fidelity of plasmid segregation

Plasmid P1 replication: negative control by repeated DNA sequences.

OpenAIRE

Chattoraj, D; Cordes, K; Abeles, A

1984-01-01

The incompatibility locus, incA, of the unit-copy plasmid P1 is contained within a fragment that is essentially a set of nine 19-base-pair repeats. One or more copies of the fragment destabilizes the plasmid when present in trans. Here we show that extra copies of incA interfere with plasmid DNA replication and that a deletion of most of incA increases plasmid copy number. Thus, incA is not essential for replication but is required for its control. When cloned in a high-copy-number vector, pi...

Necrotizing Fasciitis Caused by Inconspicuous Infection of Aeromonas hydrophila in an Immunocompromised Host

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Kuo-Chun Liao

2010-09-01

Full Text Available We present a case of serious necrotizing fasciitis due to Aeromonas hydrophila without a suggestive history of routes of pathogen invasion in a 60-year-old male. Despite prompt broad-spectrum antibiotic and extensive surgical therapies, the patient died within 72 hours following initial presentation. Our experience suggests clinicians be highly alert to the disease when an immunocompromised patient featured fulminant soft-tissue infection in the endemic area.

Antibiotic resistance plasmids of Staphylococcus aureus and their clinical importance

International Nuclear Information System (INIS)

Lacey, R.W.

1975-01-01

A variety of plasmids were isolated physically, and most antibiotic resistance is thought to be plasmid mediated. A number of characters (e.g., resistance to erythromycin or methicillin, and production of pigment) are determined by genes that do not give clear indications of either plasmid or chromosomal location. Although the formation of a particular plasmid is probably, even in bacterial terms, a very rare event, once formed such an element can spread rapidly among the bacterial population. The spectacular increase in the incidence of penicillinase-producing hospital strains in the late 1940's could have been due in part to this process. Evidence is stronger, however, for the intercell transfer of recently isolated plasmids coding for resistance to fusidic acid (and penicillinase production), or for neomycin, or for tetracycline resistance. Study of bacterial plasmids can resolve fundamental biochemical problems, and give some insight into the life of the cell at the molecular level. But the immediate application of the study of staphylococcal plasmids may be directed towards improving the effectiveness of antibiotic therapy. The most important aspect of future anti-staphylococcal chemotherapy should thus be the limitation of the use of antibiotics, particularly for application to the skin and nose. (U.S.)

Characterization of a Large Antibiotic Resistance Plasmid Found in Enteropathogenic Escherichia coli Strain B171 and Its Relatedness to Plasmids of Diverse E. coli and Shigella Strains.

Science.gov (United States)

Hazen, Tracy H; Michalski, Jane; Nagaraj, Sushma; Okeke, Iruka N; Rasko, David A

2017-09-01

Enteropathogenic Escherichia coli (EPEC) is a leading cause of severe infantile diarrhea in developing countries. Previous research has focused on the diversity of the EPEC virulence plasmid, whereas less is known regarding the genetic content and distribution of antibiotic resistance plasmids carried by EPEC. A previous study demonstrated that in addition to the virulence plasmid, reference EPEC strain B171 harbors a second, larger plasmid that confers antibiotic resistance. To further understand the genetic diversity and dissemination of antibiotic resistance plasmids among EPEC strains, we describe the complete sequence of an antibiotic resistance plasmid from EPEC strain B171. The resistance plasmid, pB171_90, has a completed sequence length of 90,229 bp, a GC content of 54.55%, and carries protein-encoding genes involved in conjugative transfer, resistance to tetracycline ( tetA ), sulfonamides ( sulI ), and mercury, as well as several virulence-associated genes, including the transcriptional regulator hha and the putative calcium sequestration inhibitor ( csi ). In silico detection of the pB171_90 genes among 4,798 publicly available E. coli genome assemblies indicates that the unique genes of pB171_90 ( csi and traI ) are primarily restricted to genomes identified as EPEC or enterotoxigenic E. coli However, conserved regions of the pB171_90 plasmid containing genes involved in replication, stability, and antibiotic resistance were identified among diverse E. coli pathotypes. Interestingly, pB171_90 also exhibited significant similarity with a sequenced plasmid from Shigella dysenteriae type I. Our findings demonstrate the mosaic nature of EPEC antibiotic resistance plasmids and highlight the need for additional sequence-based characterization of antibiotic resistance plasmids harbored by pathogenic E. coli . Copyright © 2017 American Society for Microbiology.

In Vivo Transmission of an IncA/C Plasmid in Escherichia coli Depends on Tetracycline Concentration, and Acquisition of the Plasmid Results in a Variable Cost of Fitness.

Science.gov (United States)

Johnson, Timothy J; Singer, Randall S; Isaacson, Richard E; Danzeisen, Jessica L; Lang, Kevin; Kobluk, Kristi; Rivet, Bernadette; Borewicz, Klaudyna; Frye, Jonathan G; Englen, Mark; Anderson, Janet; Davies, Peter R

2015-05-15

IncA/C plasmids are broad-host-range plasmids enabling multidrug resistance that have emerged worldwide among bacterial pathogens of humans and animals. Although antibiotic usage is suspected to be a driving force in the emergence of such strains, few studies have examined the impact of different types of antibiotic administration on the selection of plasmid-containing multidrug resistant isolates. In this study, chlortetracycline treatment at different concentrations in pig feed was examined for its impact on selection and dissemination of an IncA/C plasmid introduced orally via a commensal Escherichia coli host. Continuous low-dose administration of chlortetracycline at 50 g per ton had no observable impact on the proportions of IncA/C plasmid-containing E. coli from pig feces over the course of 35 days. In contrast, high-dose administration of chlortetracycline at 350 g per ton significantly increased IncA/C plasmid-containing E. coli in pig feces (P IncA/C plasmid to other indigenous E. coli hosts. There was no evidence of conjugal transfer of the IncA/C plasmid to bacterial species other than E. coli. In vitro competition assays demonstrated that bacterial host background substantially impacted the cost of IncA/C plasmid carriage in E. coli and Salmonella. In vitro transfer and selection experiments demonstrated that tetracycline at 32 μg/ml was necessary to enhance IncA/C plasmid conjugative transfer, while subinhibitory concentrations of tetracycline in vitro strongly selected for IncA/C plasmid-containing E. coli. Together, these experiments improve our knowledge on the impact of differing concentrations of tetracycline on the selection of IncA/C-type plasmids. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

Plasmid-Mediated Quinolone Resistance in Shigella flexneri Isolated From Macaques

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Anthony J. Mannion

2018-03-01

Full Text Available Non-human primates (NHPs for biomedical research are commonly infected with Shigella spp. that can cause acute dysentery or chronic episodic diarrhea. These animals are often prophylactically and clinically treated with quinolone antibiotics to eradicate these possible infections. However, chromosomally- and plasmid-mediated antibiotic resistance has become an emerging concern for species in the family Enterobacteriaceae. In this study, five individual isolates of multi-drug resistant Shigella flexneri were isolated from the feces of three macaques. Antibiotic susceptibility testing confirmed resistance or decreased susceptibility to ampicillin, amoxicillin-clavulanic acid, cephalosporins, gentamicin, tetracycline, ciprofloxacin, enrofloxacin, levofloxacin, and nalidixic acid. S. flexneri isolates were susceptible to trimethoprim-sulfamethoxazole, and this drug was used to eradicate infection in two of the macaques. Plasmid DNA from all isolates was positive for the plasmid-encoded quinolone resistance gene qnrS, but not qnrA and qnrB. Conjugation and transformation of plasmid DNA from several S. flexneri isolates into antibiotic-susceptible Escherichia coli strains conferred the recipients with resistance or decreased susceptibility to quinolones and beta-lactams. Genome sequencing of two representative S. flexneri isolates identified the qnrS gene on a plasmid-like contig. These contigs showed >99% homology to plasmid sequences previously characterized from quinolone-resistant Shigella flexneri 2a and Salmonella enterica strains. Other antibiotic resistance genes and virulence factor genes were also identified in chromosome and plasmid sequences in these genomes. The findings from this study indicate macaques harbor pathogenic S. flexneri strains with chromosomally- and plasmid-encoded antibiotic resistance genes. To our knowledge, this is the first report of plasmid-mediated quinolone resistance in S. flexneri isolated from NHPs and warrants

Complete sequencing of IncI1 sequence type 2 plasmid pJIE512b indicates mobilization of blaCMY-2 from an IncA/C plasmid.

Science.gov (United States)

Tagg, Kaitlin A; Iredell, Jonathan R; Partridge, Sally R

2014-08-01

Sequencing of pJIE512b, a 92.3-kb IncI1 sequence type 2 (ST2) plasmid carrying bla(CMY-2), revealed a bla(CMY-2) context that appeared to have been mobilized from an IncA/C plasmid by the insertion sequence IS1294. A comparison with published plasmids suggests that bla(CMY-2) has been mobilized from IncA/C to IncI1 plasmids more than once by IS1294-like elements. Alignment of pJIE512b with the only other available IncI1 ST2 plasmid revealed differences across the backbones, indicating variability within this sequence type. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Novel assay to measure the plasmid mobilizing potential of mixed microbial communities

DEFF Research Database (Denmark)

Klümper, Uli; Droumpali, Ariadni; Dechesne, Arnaud

2014-01-01

Mobilizable plasmids lack necessary genes for complete conjugation and are therefore non-self-transmissible. Instead, they rely on the conjugation system of conjugal plasmids to be horizontally transferred to new recipients. While community permissiveness, the fraction of a mixed microbial...... community that can receive self-transmissible conjugal plasmids, has been studied, the intrinsic ability of a community to mobilize plasmids that lack conjugation systems is unexplored. Here, we present a novel framework and experimental method to estimate the mobilization potential of mixed communities. We...... of the donors receiving the conjugal plasmid in the first step. Further work is needed to establish how plasmid mobilization potential varies within and across microbial communities....

Development of a self-replicating plasmid system for Mycoplasma hyopneumoniae.

Science.gov (United States)

Maglennon, Gareth A; Cook, Beth S; Matthews, Dominic; Deeney, Alannah S; Bossé, Janine T; Langford, Paul R; Maskell, Duncan J; Tucker, Alexander W; Wren, Brendan W; Rycroft, Andrew N

2013-07-29

Mycoplasma hyopneumoniae is a prevalent swine respiratory pathogen that is a major cause of economic loss to pig producers. Control is achieved by a combination of antimicrobials, vaccination and management practices, but current vaccines offer only partial control and there is a need for improved preventative strategies. A major barrier to advances in understanding the pathogenesis of M. hyopneumoniae and in developing new vaccines is the lack of tools to genetically manipulate the organism. We describe the development and optimisation of the first successful plasmid-based system for the genetic manipulation of M. hyopneumoniae. Our artificial plasmids contain the origin of replication (oriC) of M. hyopneumoniae along with tetM, conferring resistance to tetracycline. With these plasmids, we have successfully transformed M. hyopneumoniae strain 232 by electroporation, generating tetracycline resistant organisms. The persistence of extrachromosomal plasmid and maintenance of plasmid DNA over serial passages shows that these artificial plasmids are capable of self-replication in M. hyopneumoniae. In addition to demonstrating the amenability of M. hyopneumoniae to genetic manipulation and in optimising the conditions necessary for successful transformation, we have used this system to determine the minimum functional oriC of M. hyopneumoniae. In doing so, we have developed a plasmid with a small oriC that is stably maintained over multiple passages that may be useful in generating targeted gene disruptions. In conclusion, we have generated a set of plasmids that will be valuable in studies of M. hyopneumoniae pathogenesis and provide a major step forward in the study of this important swine pathogen.

Production and pharmaceutical formulation of plasmid DNA vaccines

NARCIS (Netherlands)

van der Heijden, I.

2013-01-01

Research leading to the thesis ‘Production and pharmaceutical formulation of plasmid DNA vaccines‘ can be divided into two parts. The first part describes the development of a Good Manufacturing Practice (GMP) compliant plasmid DNA production process of pDNA vaccines for the treatment of Human

Photoinduced silver nanoparticles/nanorings on plasmid DNA scaffolds.

Science.gov (United States)

Liu, Jianhua; Zhang, Xiaoliang; Yu, Mei; Li, Songmei; Zhang, Jindan

2012-01-23

Biological scaffolds are being actively explored for the synthesis of nanomaterials with novel structures and unexpected properties. Toroidal plasmid DNA separated from the Bacillus host is applied as a sacrificial mold for the synthesis of silver nanoparticles and nanorings. The photoirradiation method is applied to reduce Ag(I) on the plasmid. The nanoparticles are obtained by varying the concentration of the Ag(I) ion solution and the exposure time of the plasmid-Ag(I) complex under UV light at 254 nm and room temperature. It is found that the plasmid serves not only as a template but also as a reductant to drive the silver nucleation and deposition. The resulting nanoparticles have a face-centered cubic (fcc) crystal structure and 20-30 nm average diameter. The detailed mechanism is discussed, and other metals or alloys could also be synthesized with this method. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Total protein electrophoresis and RAPD fingerprinting analysis for the identification of Aeromonas at the species level Análise eletroforética de proteínas totais e marcadores de RAPD na identificação de Aeromonas ao nível de espécie

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Ana Paula Longaray Delamare

2002-12-01

Full Text Available Fifteen well-defined strains of Aeromonas of thirteen species were analyzed by SDS protein electrophoretic analysis (SDS-PAGE and random amplified polymorphic DNA analysis (RAPD. The comparison between the patterns obtained by both methods allowed differentiating all the strains. Clusters formed by the unweighted pair group method with arithmetic averages applied to protein data correlates with the genetic and biochemical information about the species. The results show that protein fingerprinting has the potential to differentiate Aeromonas species, but the low qualitative variation indicates that this technique is not efficient for the characterization of strains within a species. Conversely, RAPD fingerprinting allows the identification of strains but the high variability limits its potential as an aiding method for species identification.Quinze linhagens de Aeromonas pertencentes a treze espécies foram avaliadas através de eletroforese de proteínas totais (SDS-PAGE e segmentos de DNA amplificados ao acaso (RAPD. A comparação entre os padrões obtidos por ambos métodos permitiu diferenciar todas as linhagens. Agrupamentos formados com base nos dados protéicos mostraram relação com informações bioquímicas e genéticas a respeito das espécies. Os resultados mostraram que análises protéicas têm potencial para diferenciar espécies de Aeromonas, mas a baixa variação qualitativa indica que esta técnica não é eficiente para a caracterização entre linhagens dentro de espécies. Ao contrário, marcadores de RAPD permitem identificar linhagens, mas a alta variabilidade limita seu potencial como método auxiliar na identificação de espécies.

Plasmids and rickettsial evolution: insight from Rickettsia felis.

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Joseph J Gillespie

2007-03-01

Full Text Available The genome sequence of Rickettsia felis revealed a number of rickettsial genetic anomalies that likely contribute not only to a large genome size relative to other rickettsiae, but also to phenotypic oddities that have confounded the categorization of R. felis as either typhus group (TG or spotted fever group (SFG rickettsiae. Most intriguing was the first report from rickettsiae of a conjugative plasmid (pRF that contains 68 putative open reading frames, several of which are predicted to encode proteins with high similarity to conjugative machinery in other plasmid-containing bacteria.Using phylogeny estimation, we determined the mode of inheritance of pRF genes relative to conserved rickettsial chromosomal genes. Phylogenies of chromosomal genes were in agreement with other published rickettsial trees. However, phylogenies including pRF genes yielded different topologies and suggest a close relationship between pRF and ancestral group (AG rickettsiae, including the recently completed genome of R. bellii str. RML369-C. This relatedness is further supported by the distribution of pRF genes across other rickettsiae, as 10 pRF genes (or inactive derivatives also occur in AG (but not SFG rickettsiae, with five of these genes characteristic of typical plasmids. Detailed characterization of pRF genes resulted in two novel findings: the identification of oriV and replication termination regions, and the likelihood that a second proposed plasmid, pRFdelta, is an artifact of the original genome assembly.Altogether, we propose a new rickettsial classification scheme with the addition of a fourth lineage, transitional group (TRG rickettsiae, that is unique from TG and SFG rickettsiae and harbors genes from possible exchanges with AG rickettsiae via conjugation. We offer insight into the evolution of a plastic plasmid system in rickettsiae, including the role plasmids may have played in the acquirement of virulence traits in pathogenic strains, and the

Processing of Nonconjugative Resistance Plasmids by Conjugation Nicking Enzyme of Staphylococci

Energy Technology Data Exchange (ETDEWEB)

Pollet, Rebecca M.; Ingle, James D.; Hymes, Jeff P.; Eakes, Thomas C.; Eto, Karina Yui; Kwong, Stephen M.; Ramsay, Joshua P.; Firth, Neville; Redinbo, Matthew R. (Curtin U.); (Sydney); (UNC)

2016-01-04

Antimicrobial resistance inStaphylococcus aureuspresents an increasing threat to human health. This resistance is often encoded on mobile plasmids, such as pSK41; however, the mechanism of transfer of these plasmids is not well understood. In this study, we first examine key protein-DNA interactions formed by the relaxase enzyme, NES, which initiates and terminates the transfer of the multidrug resistance plasmid pSK41. Two loops on the NES protein, hairpin loops 1 and 2, form extensive contacts with the DNA hairpin formed at theoriTregion of pSK41, and here we establish that these contacts are essential for proper DNA cleavage and religation by the full 665-residue NES proteinin vitro. Second, pSK156 and pCA347 are nonconjugativeStaphylococcus aureusplasmids that contain sequences similar to theoriTregion of pSK41 but differ in the sequence predicted to form a DNA hairpin. We show that pSK41-encoded NES is able to bind, cleave, and religate theoriTsequences of these nonconjugative plasmidsin vitro. Although pSK41 could mobilize a coresident plasmid harboring its cognateoriT, it was unable to mobilize plasmids containing the pSK156 and pCA347 variantoriTmimics, suggesting that an accessory protein like that previously shown to confer specificity in the pWBG749 system may also be involved in transmission of plasmids containing a pSK41-likeoriT. These data indicate that the conjugative relaxase intransmechanism recently described for the pWBG749 family of plasmids also applies to the pSK41 family of plasmids, further heightening the potential significance of this mechanism in the horizontal transfer of staphylococcal plasmids.

IMPORTANCEUnderstanding the

Characterisation of potential virulence markers in Aeromonas caviae isolated from polluted and unpolluted aquatic environments in Morocco

DEFF Research Database (Denmark)

Imziln, Boujama; Krovacek, Karel; Baloda, Suraj B.

1998-01-01

A total of 100 Aeromonas caviae strains isolated from river waters (38 isolates), raw sewage (30 isolates) and effluents of stabilisation ponds (i.e. treated sewage; 32 isolates) in Marrakech, Morocco, were tested for the presence of putative virulence factors to delineate differences, if any...

Mechanisms of Evolution in High-Consequence Drug Resistance Plasmids.

Science.gov (United States)

He, Susu; Chandler, Michael; Varani, Alessandro M; Hickman, Alison B; Dekker, John P; Dyda, Fred

2016-12-06

The dissemination of resistance among bacteria has been facilitated by the fact that resistance genes are usually located on a diverse and evolving set of transmissible plasmids. However, the mechanisms generating diversity and enabling adaptation within highly successful resistance plasmids have remained obscure, despite their profound clinical significance. To understand these mechanisms, we have performed a detailed analysis of the mobilome (the entire mobile genetic element content) of a set of previously sequenced carbapenemase-producing Enterobacteriaceae (CPE) from the National Institutes of Health Clinical Center. This analysis revealed that plasmid reorganizations occurring in the natural context of colonization of human hosts were overwhelmingly driven by genetic rearrangements carried out by replicative transposons working in concert with the process of homologous recombination. A more complete understanding of the molecular mechanisms and evolutionary forces driving rearrangements in resistance plasmids may lead to fundamentally new strategies to address the problem of antibiotic resistance. The spread of antibiotic resistance among Gram-negative bacteria is a serious public health threat, as it can critically limit the types of drugs that can be used to treat infected patients. In particular, carbapenem-resistant members of the Enterobacteriaceae family are responsible for a significant and growing burden of morbidity and mortality. Here, we report on the mechanisms underlying the evolution of several plasmids carried by previously sequenced clinical Enterobacteriaceae isolates from the National Institutes of Health Clinical Center (NIH CC). Our ability to track genetic rearrangements that occurred within resistance plasmids was dependent on accurate annotation of the mobile genetic elements within the plasmids, which was greatly aided by access to long-read DNA sequencing data and knowledge of their mechanisms. Mobile genetic elements such as

Type 3 Fimbriae Encoded on Plasmids Are Expressed from a Unique Promoter without Affecting Host Motility, Facilitating an Exceptional Phenotype That Enhances Conjugal Plasmid Transfer

DEFF Research Database (Denmark)

Madsen, Jonas Stenlokke; Riber, Leise; Kot, Witold

2016-01-01

Horizontal gene transfer (HGT), the transmission of genetic material to a recipient that is not the progeny of the donor, is fundamental in bacterial evolution. HGT is often mediated by mobile genetic elements such as conjugative plasmids, which may be in conflict with the chromosomal elements...... of the genome because they are independent replicons that may petition their own evolutionary strategy. Here we study differences between type 3 fimbriae encoded on wild type plasmids and in chromosomes. Using known and newly characterized plasmids we show that the expression of type 3 fimbriae encoded...... on plasmids is systematically different, as MrkH, a c-di-GMP dependent transcriptional activator is not needed for strong expression of the fimbriae. MrkH is required for expression of type 3 fimbriae of the Klebsiella pneumoniae chromosome, wherefrom the fimbriae operon (mrkABCDF) of plasmids is believed...

Resistant plasmid profile analysis of multidrug resistant Escherichia ...

African Journals Online (AJOL)

Multiple drug resistance isolates causing UTI has seri- ous implications for the empiric therapy against patho- genic isolates and for the possible co-selection of antimicrobial resistant mediated by multi drug resistant plasmids21,22. E. coli from clinical isolates are known to harbour plasmids of different molecular sizes23.

Candidate nematicidal proteins in a new Pseudomonas veronii isolate identified by its antagonistic properties against Xiphinema index.

Science.gov (United States)

Canchignia, Hayron; Altimira, Fabiola; Montes, Christian; Sánchez, Evelyn; Tapia, Eduardo; Miccono, María; Espinoza, Daniel; Aguirre, Carlos; Seeger, Michael; Prieto, Humberto

2017-03-17

The nematode Xiphinema index affects grape vines and transmits important viruses associated with fanleaf degeneration. Pseudomonas spp. are an extensive bacterial group in which important biodegradation and/or biocontrol properties can occur for several strains in the group. The aim of this study was to identify new Pseudomonas isolates with antagonist activity against X. index. Forty bacterial isolates were obtained from soil and root samples from Chilean vineyards. Thirteen new fluorescent pseudomonads were found and assessed for their antagonistic capability. The nematicide Pseudomonas protegens CHA0 was used as a control. Challenges of nematode individuals in King's B semi-solid agar Petri dishes facilitated the identification of the Pseudomonas veronii isolate R4, as determined by a 16S rRNA sequence comparison. This isolate was as effective as CHA0 as an antagonist of X. index, although it had a different lethality kinetic. Milk-induced R4 cultures exhibited protease and lipase activities in cell supernatants using both gelatin/tributyrin Petri dish assays and zymograms. Three proteins with these activities were isolated and subjected to mass spectrometry. Amino acid partial sequences enabled the identification of a 49-kDa protease similar to metalloprotease AprA and two lipases of 50 kDa and 69 kDa similar to LipA and ExoU, respectively. Electron microscopy analyses of challenged nematodes revealed degraded cuticle after R4 supernatant treatment. These results represent a new and unexplored property in this species associated with the presence of secretable lipases and protease, similar to characterized enzymes present in biocontrol pseudomonads.

Comparative evaluation of infection methods and environmental factors on challenge success: Aeromonas salmonicida infection in vaccinated rainbow trout

DEFF Research Database (Denmark)

Chettri, Jiwan Kumar; Skov, Jakob; Jaafar, Rzgar M.

2015-01-01

When testing vaccine-induced protection an effective and reliable challenge method is a basic requirement and we here present a comparative study on different challenge methods used for infection of rainbow trout Oncorhynchus mykiss with Aeromonas salmonicida, a bacterial pathogen eliciting...

IncA/C plasmids: An emerging threat to human and animal health?

Science.gov (United States)

Johnson, Timothy J; Lang, Kevin S

2012-01-01

Incompatibility group IncA/C plasmids are large, low copy, theta-replicating plasmids that have been described in the literature for over 40 years. However, they have only recently been intensively studied on the genomic level because of their associations with the emergence of multidrug resistance in enteric pathogens of humans and animals. These plasmids are unique among other enterobacterial plasmids in many aspects, including their modular structure and gene content. While the IncA/C plasmid genome structure has now been well defined, many questions remain pertaining to their basic biological mechanisms of dissemination and regulation. Here, we discuss the history of IncA/C plasmids in light of our recent understanding of their population distribution, genomics, and effects on host bacteria.

Draft genome sequence of Pseudomonas mosselii Gil3, isolated from catfish and antagonistic against hypervirulent Aeromonas hydrophila

Science.gov (United States)

Pseudomonas mosselii Gil3 was isolated from a catfish that survived from lethal challenge with hypervirulent Aeromonas hydrophila (vAh). When assayed in vitro, the bacterium showed antagonism against vAh. Sequence analysis revealed that the genome of P. mosselii Gil3 encodes numerous aromatic metabo...

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African Journals Online (AJOL)

yakoub@AHMED

Aeromonas spp in diřřerent řood sources and human inřections. Thirty řive .... Plasmid Isolation: LB broth plus appropriate antibioticsin culture tubes with each ... [50 mM Tris (pH 8.0); 20 mM Nacl and 5 mM EDTA] plus digestion oř RNA using.

AAVS1-Targeted Plasmid Integration in AAV Producer Cell Lines.

Science.gov (United States)

Luo, Yuxia; Frederick, Amy; Martin, John M; Scaria, Abraham; Cheng, Seng H; Armentano, Donna; Wadsworth, Samuel C; Vincent, Karen A

2017-06-01

Adeno-associated virus (AAV) producer cell lines are created via transfection of HeLaS3 cells with a single plasmid containing three components (the vector sequence, the AAV rep and cap genes, and a selectable marker gene). As this plasmid contains both the cis (Rep binding sites) and trans (Rep protein encoded by the rep gene) elements required for site-specific integration, it was predicted that plasmid integration might occur within the AAVS1 locus on human chromosome 19 (chr19). The objective of this study was to investigate whether integration in AAVS1 might be correlated with vector yield. Plasmid integration sites within several independent cell lines were assessed via Southern, fluorescence in situ hybridization (FISH) and PCR analyses. In the Southern analyses, the presence of fragments detected by both rep- and AAVS1-specific probes suggested that for several mid- and high-producing lines, plasmid DNA had integrated into the AAVS1 locus. Analysis with puroR and AAVS1-specific probes suggested that integration in AAVS1 was a more widespread phenomenon. High-producing AAV2-secreted alkaline phosphatase (SEAP) lines (masterwell 82 [MW82] and MW278) were evaluated via FISH using probes specific for the plasmid, AAVS1, and a chr19 marker. FISH analysis detected two plasmid integration sites in MW278 (neither in AAVS1), while a total of three sites were identified in MW82 (two in AAVS1). An inverse PCR assay confirmed integration within AAVS1 for several mid- and high-producing lines. In summary, the FISH, Southern, and PCR data provide evidence of site-specific integration of the plasmid within AAVS1 in several AAV producer cell lines. The data also suggest that integration in AAVS1 is a general phenomenon that is not necessarily restricted to high producers. The results also suggest that plasmid integration within the AAVS1 locus is not an absolute requirement for a high vector yield.

Functional analysis of three plasmids from Lactobacillus plantarum

NARCIS (Netherlands)

Kranenburg, R. van; Golic, N.; Bongers, R.; Leer, R.J.; Vos, W.M. de; Siezen, R.J.; Kleerebezem, M.

2005-01-01

Lactobacillus plantarum WCFS1 harbors three plasmids, pWCFS101, pWCFS102, and pWCFS103, with sizes of 1,917, 2,365, and 36,069 bp, respectively. The two smaller plasmids are of unknown function and contain replication genes that are likely to function via the rolling-circle replication mechanism.

The technology of large-scale pharmaceutical plasmid purification ...

African Journals Online (AJOL)

Further test demonstrated that the pcDNAlacZ purified with CTAB and authoritative endotoxin-free plasmid Kit had the similar transfection efficiency in vivo and in vitro. CTAB can be used for plasmid purification; the main advantages of the DNAs purified with CTAB include the avoidance of animal-derived enzymes, toxic ...

Molecular Phylogenetics and Temporal Diversification in the Genus Aeromonas Based on the Sequences of Five Housekeeping Genes

Science.gov (United States)

Lorén, J. Gaspar; Farfán, Maribel; Fusté, M. Carmen

2014-01-01

Several approaches have been developed to estimate both the relative and absolute rates of speciation and extinction within clades based on molecular phylogenetic reconstructions of evolutionary relationships, according to an underlying model of diversification. However, the macroevolutionary models established for eukaryotes have scarcely been used with prokaryotes. We have investigated the rate and pattern of cladogenesis in the genus Aeromonas (γ-Proteobacteria, Proteobacteria, Bacteria) using the sequences of five housekeeping genes and an uncorrelated relaxed-clock approach. To our knowledge, until now this analysis has never been applied to all the species described in a bacterial genus and thus opens up the possibility of establishing models of speciation from sequence data commonly used in phylogenetic studies of prokaryotes. Our results suggest that the genus Aeromonas began to diverge between 248 and 266 million years ago, exhibiting a constant divergence rate through the Phanerozoic, which could be described as a pure birth process. PMID:24586399

Role of plasmids in Lactobacillus brevis BSO 464 hop tolerance and beer spoilage.

Science.gov (United States)

Bergsveinson, Jordyn; Baecker, Nina; Pittet, Vanessa; Ziola, Barry

2015-02-01

Specific isolates of lactic acid bacteria (LAB) can grow in the harsh beer environment, thus posing a threat to brew quality and the economic success of breweries worldwide. Plasmid-localized genes, such as horA, horC, and hitA, have been suggested to confer hop tolerance, a trait required for LAB survival in beer. The presence and expression of these genes among LAB, however, do not universally correlate with the ability to grow in beer. Genome sequencing of the virulent beer spoilage organism Lactobacillus brevis BSO 464 revealed the presence of eight plasmids, with plasmids 1, 2, and 3 containing horA, horC, and hitA, respectively. To investigate the roles that these and the other five plasmids play in L. brevis BSO 464 growth in beer, plasmid curing with novobiocin was used to derive 10 plasmid variants. Multiplex PCRs were utilized to determine the presence or absence of each plasmid, and how plasmid loss affected hop tolerance and growth in degassed (noncarbonated) beer was assessed. Loss of three of the eight plasmids was found to affect hop tolerance and growth in beer. Loss of plasmid 2 (horC and 28 other genes) had the most dramatic effect, with loss of plasmid 4 (120 genes) and plasmid 8 (47 genes) having significant, but smaller, impacts. These results support the contention that genes on mobile genetic elements are essential for bacterial growth in beer and that beer spoilage ability is not dependent solely on the three previously described hop tolerance genes or on the chromosome of a beer spoilage LAB isolate.

Isolation and Identification of Aeromonas hydrophila and Saprolegnia sp. on Catfish (Clarias gariepinus) in Floating cages in Bozem Moro Krembangan Surabaya

Science.gov (United States)

Kusdarwati, Rahayu; Kismiyati; Sudarno; Kurniawan, Hendi; Teguh Prayogi, Yudha

2017-02-01

Catfish (Clarias gariepinus) is one of the familiar freshwater fish cultured in Indonesia farmer. One of the reason is the high mortality of the catfish infected by Aeromonas hydrophila and Saprolegnia sp. Motile Aeromonas septicemia (MAS) is a common bacterial disease, caused by Aeromonas hydrophila, which affects freshwater fish. In Southeast Asia, the outbreak of this disease was firstly reported from West Java in 1980, when a total of 82.5 tons a month of catfish were lost, while in Central Java in 1984, the total loss was 1.6 tons. Saprolegniosis can cause economic loss due to high mortality from its case reaching 10% to 50%. This research aimed to identify and determine the percentage of A. hydrophila and Saprolegnia sp. the catfish farmed in bozem Moro Krembangan, Surabaya, East Java. Meanwhile, a supporting parameter in this research is the value of water quality parameter including pH, temperature, ammonia and dissolved oxygen that were measured during sampling. The results showed that of the 20 samples taken from the two cages, 19 fish were positively infected by A. drophila. percentage of infections of A. hydrophila that infect umbo catfish in Moro Krembangan, was 95%, while the percentage Saprolegnia sp. was 90%.

Transformation of Saccharomyces cerevisiae with UV-irradiated single-stranded plasmid.

Science.gov (United States)

Zgaga, Z

1991-08-01

UV-irradiated single-stranded replicative plasmids were used to transform different yeast strains. The low doses of UV used in this study (10-75 J/m2) caused a significant decrease in the transforming efficiency of plasmid DNA in the Rad+ strain, while they had no effect on transformation with double-stranded plasmids of comparable size. Neither the rev3 mutation, nor the rad18 or rad52 mutations influenced the efficiency of transformation with irradiated single-stranded plasmid. However, it was found to be decreased in the double rev3 rad52 mutant. Extracellular irradiation of plasmid that contains both URA3 and LEU2 genes (psLU) gave rise to up to 5% Leu- transformants among selected Ura+ ones in the repair-proficient strain. Induction of Leu- transformants was dose-dependent and only partially depressed in the rev3 mutant. These results suggest that both mutagenic and recombinational repair processes operate on UV-damaged single-stranded DNA in yeast.

Thin-film fixed-bed reactor for solar photocatalytic inactivation of Aeromonas hydrophila: influence of water quality

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Khan Sadia J

2012-11-01

Full Text Available Abstract Background Controlling fish disease is one of the major concerns in contemporary aquaculture. The use of antibiotics or chemical disinfection cannot provide a healthy aquaculture system without residual effects. Water quality is also important in determining the success or failure of fish production. Several solar photocatalytic reactors have been used to treat drinking water or waste water without leaving chemical residues. This study has investigated the impact of several key aspects of water quality on the inactivation of the pathogenic bacterium Aeromonas hydrophila using a pilot-scale thin-film fixed-bed reactor (TFFBR system. Results The level of inactivation of Aeromonas hydrophila ATCC 35654 was determined using a TFFBR with a photocatalytic area of 0.47 m2 under the influence of various water quality variables (pH, conductivity, turbidity and colour under high solar irradiance conditions (980–1100 W m-2, at a flow rate of 4.8 L h-1 through the reactor. Bacterial enumeration were obtained through conventional plate count using trypticase soy agar media, cultured in conventional aerobic conditions to detect healthy cells and under ROS-neutralised conditions to detect both healthy and sub-lethally injured (oxygen-sensitive cells. The results showed that turbidity has a major influence on solar photocatalytic inactivation of A. hydrophila. Humic acids appear to decrease TiO2 effectiveness under full sunlight and reduce microbial inactivation. pH in the range 7–9 and salinity both have no major effect on the extent of photoinactivation or sub-lethal injury. Conclusions This study demonstrates the effectiveness of the TFFBR in the inactivation of Aeromonas hydrophila under the influence of several water quality variables at high solar irradiance, providing an opportunity for the application of solar photocatalysis in aquaculture systems, as long as turbidity remains low.

Comparative Sequence Analysis of Multidrug-Resistant IncA/C Plasmids from Salmonella enterica.

Science.gov (United States)

Hoffmann, Maria; Pettengill, James B; Gonzalez-Escalona, Narjol; Miller, John; Ayers, Sherry L; Zhao, Shaohua; Allard, Marc W; McDermott, Patrick F; Brown, Eric W; Monday, Steven R

2017-01-01

Determinants of multidrug resistance (MDR) are often encoded on mobile elements, such as plasmids, transposons, and integrons, which have the potential to transfer among foodborne pathogens, as well as to other virulent pathogens, increasing the threats these traits pose to human and veterinary health. Our understanding of MDR among Salmonella has been limited by the lack of closed plasmid genomes for comparisons across resistance phenotypes, due to difficulties in effectively separating the DNA of these high-molecular weight, low-copy-number plasmids from chromosomal DNA. To resolve this problem, we demonstrate an efficient protocol for isolating, sequencing and closing IncA/C plasmids from Salmonella sp. using single molecule real-time sequencing on a Pacific Biosciences (Pacbio) RS II Sequencer. We obtained six Salmonella enterica isolates from poultry, representing six different serovars, each exhibiting the MDR-Ampc resistance profile. Salmonella plasmids were obtained using a modified mini preparation and transformed with Escherichia coli DH10Br. A Qiagen Large-Construct kit™ was used to recover highly concentrated and purified plasmid DNA that was sequenced using PacBio technology. These six closed IncA/C plasmids ranged in size from 104 to 191 kb and shared a stable, conserved backbone containing 98 core genes, with only six differences among those core genes. The plasmids encoded a number of antimicrobial resistance genes, including those for quaternary ammonium compounds and mercury. We then compared our six IncA/C plasmid sequences: first with 14 IncA/C plasmids derived from S. enterica available at the National Center for Biotechnology Information (NCBI), and then with an additional 38 IncA/C plasmids derived from different taxa. These comparisons allowed us to build an evolutionary picture of how antimicrobial resistance may be mediated by this common plasmid backbone. Our project provides detailed genetic information about resistance genes in

Comparative Sequence Analysis of Multidrug-Resistant IncA/C Plasmids from Salmonella enterica

Directory of Open Access Journals (Sweden)

Maria Hoffmann

2017-08-01

Full Text Available Determinants of multidrug resistance (MDR are often encoded on mobile elements, such as plasmids, transposons, and integrons, which have the potential to transfer among foodborne pathogens, as well as to other virulent pathogens, increasing the threats these traits pose to human and veterinary health. Our understanding of MDR among Salmonella has been limited by the lack of closed plasmid genomes for comparisons across resistance phenotypes, due to difficulties in effectively separating the DNA of these high-molecular weight, low-copy-number plasmids from chromosomal DNA. To resolve this problem, we demonstrate an efficient protocol for isolating, sequencing and closing IncA/C plasmids from Salmonella sp. using single molecule real-time sequencing on a Pacific Biosciences (Pacbio RS II Sequencer. We obtained six Salmonella enterica isolates from poultry, representing six different serovars, each exhibiting the MDR-Ampc resistance profile. Salmonella plasmids were obtained using a modified mini preparation and transformed with Escherichia coli DH10Br. A Qiagen Large-Construct kit™ was used to recover highly concentrated and purified plasmid DNA that was sequenced using PacBio technology. These six closed IncA/C plasmids ranged in size from 104 to 191 kb and shared a stable, conserved backbone containing 98 core genes, with only six differences among those core genes. The plasmids encoded a number of antimicrobial resistance genes, including those for quaternary ammonium compounds and mercury. We then compared our six IncA/C plasmid sequences: first with 14 IncA/C plasmids derived from S. enterica available at the National Center for Biotechnology Information (NCBI, and then with an additional 38 IncA/C plasmids derived from different taxa. These comparisons allowed us to build an evolutionary picture of how antimicrobial resistance may be mediated by this common plasmid backbone. Our project provides detailed genetic information about

Long- term manure exposure increases soil bacterial community potential for plasmid uptake

DEFF Research Database (Denmark)

Musovic, Sanin; Klümper, Uli; Dechesne, Arnaud

2014-01-01

Microbial communities derived from soils subject to different agronomic treatments were challenged with three broad host range plasmids, RP4, pIPO2tet and pRO101, via solid surface filter matings to assess their permissiveness. Approximately 1 in 10 000 soil bacterial cells could receive and main......Microbial communities derived from soils subject to different agronomic treatments were challenged with three broad host range plasmids, RP4, pIPO2tet and pRO101, via solid surface filter matings to assess their permissiveness. Approximately 1 in 10 000 soil bacterial cells could receive...... and maintain the plasmids. The community permissiveness increased up to 100% in communities derived from manured soil. While the plasmid transfer frequency was significantly influenced by both the type of plasmid and the agronomic treatment, the diversity of the transconjugal pools was purely plasmid dependent...

Inventarisatie van Aeromonas spp. in het drinkwater van 21 pompstations in de periode september 1985-december 1986 (deel I)

NARCIS (Netherlands)

Versteegh JFM; During M; Havelaar AH

1987-01-01

In de periode september 1985-december 1986 is in samenwerking met een aantal drinkwaterbedrijven een inventariserend onderzoek uitgevoerd naar het voorkomen van Aeromonas-bacterien in verschillende typen drinkwater geproduceerd op 21 drinkwaterpompstations. Nadat in de loop van het onderzoek

Inventarisatie van Aeromonas spp. in het drinkwater van 21 pompstations in de periode september 1985-december 1986 (deel II)

NARCIS (Netherlands)

Versteegh JFM; During M; Havelaar AH

1987-01-01

In de periode september 1985-december 1986 is in samenwerking met een aantal drinkwaterbedrijven een inventariserend onderzoek uitgevoerd naar het voorkomen van Aeromonas-bacterien in verschillende typen drinkwater geproduceerd op 21 drinkwaterpompstations. Nadat in de loop van het onderzoek

Antibiotic and heavy metal resistance of Aeromonas hydrophila and Edwardsiella tarda isolated from red hybrid tilapia (Oreochromis spp. coinfected with motile aeromonas septicemia and edwardsiellosis

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S. W. Lee

2017-07-01

Full Text Available Aim: The aim of this study is to identify antibiogram and heavy metal resistance pattern of Aeromonas hydrophila and Edwardsiella tarda isolated from red hybrid tilapia (Oreochromis spp. coinfected with motile aeromonas septicemia and edwardsiellosis in four commercial fish farms. Materials and Methods: A. hydrophila and E. tarda were isolated using glutamate starch phenol red and xylose lysine deoxycholate (Merck, Germany as a selective medium, respectively. All the suspected bacterial colonies were identified using conventional biochemical tests and commercial identification kit (BBL Crystal, USA. Susceptibility testing of present bacterial isolates to 16 types of antibiotics (nalidixic acid, oxolinic acid, compound sulfonamides, doxycycline, tetracycline, novobiocin, chloramphenicol, kanamycin, sulfamethoxazole, flumequine, erythromycin, ampicillin, spiramycin, oxytetracycline, amoxicillin, and fosfomycin and four types of heavy metals (mercury, chromium, copper, and zinc were carried out using disk diffusion and two-fold agar dilution method, respectively. Results: Three hundred isolates of A. hydrophila and E. tarda were successfully identified by biochemical tests. Antibiotic susceptibility testing results showed that 42.2% of the bacterial isolates were sensitive to compound sulfonamides, sulfamethoxazole, flumequine, oxytetracycline, doxycycline, and oxolinic acid. On the other hand, 41.6% of these isolates were resistant to novobiocin, ampicillin, spiramycin, and chloramphenicol, which resulted for multiple antibiotic resistance index values 0.416. Among tested heavy metals, bacterial isolates exhibited resistant pattern of Zn2+ > Cr6+ > Cu2+ > Hg2+. Conclusion: Results from this study indicated that A. hydrophila and E. tarda isolated from coinfected farmed red hybrid tilapia were multi-resistant to antibiotics and heavy metals. These resistant profiles could be useful information to fish farmers to avoid unnecessary use of

Prevalence of plasmid-bearing and plasmid-free Chlamydia trachomatis infection among women who visited obstetrics and gynecology clinics in Malaysia

OpenAIRE

Yeow, Tee Cian; Wong, Won Fen; Sabet, Negar Shafiei; Sulaiman, Sofiah; Shahhosseini, Fatemeh; Tan, Grace Min Yi; Movahed, Elaheh; Looi, Chung Yeng; Shankar, Esaki M.; Gupta, Rishien; Arulanandam, Bernard P.; Hassan, Jamiyah; Abu Bakar, Sazaly

2016-01-01

Background The 7.5?kb cryptic plasmid of Chlamydia trachomatis has been shown to be a virulence factor in animal models, but its significance in humans still remains unknown. The aim of this study was to investigate the prevalence and potential involvement of the C. trachomatis cryptic plasmid in causing various clinical manifestations; including infertility, reproductive tract disintegrity, menstrual disorder, and polycystic ovarian syndrome (PCOS) among genital C. trachomatis?infected patie...

Genome Stability of Lyme Disease Spirochetes: Comparative Genomics of Borrelia burgdorferi Plasmids

Energy Technology Data Exchange (ETDEWEB)

Casjens S. R.; Dunn J.; Mongodin, E. F.; Qiu, W.-G.; Luft, B. J.; Schutzer, S. E.; Gilcrease, E. B.; Huang, W. M.; Vujadinovic, M.; Aron, J. K.; Vargas, L. C.; Freeman, S.; Radune, D.; Weidman, J. F.; Dimitrov, G. I.; Khouri, H. M.; Sosa, J. E.; Halpin, R. A.; Fraser, C. M.

2012-03-14

Lyme disease is the most common tick-borne human illness in North America. In order to understand the molecular pathogenesis, natural diversity, population structure and epizootic spread of the North American Lyme agent, Borrelia burgdorferi sensu stricto, a much better understanding of the natural diversity of its genome will be required. Towards this end we present a comparative analysis of the nucleotide sequences of the numerous plasmids of B. burgdorferi isolates B31, N40, JD1 and 297. These strains were chosen because they include the three most commonly studied laboratory strains, and because they represent different major genetic lineages and so are informative regarding the genetic diversity and evolution of this organism. A unique feature of Borrelia genomes is that they carry a large number of linear and circular plasmids, and this work shows that strains N40, JD1, 297 and B31 carry related but non-identical sets of 16, 20, 19 and 21 plasmids, respectively, that comprise 33-40% of their genomes. We deduce that there are at least 28 plasmid compatibility types among the four strains. The B. burgdorferi {approx}900 Kbp linear chromosomes are evolutionarily exceptionally stable, except for a short {le}20 Kbp plasmid-like section at the right end. A few of the plasmids, including the linear lp54 and circular cp26, are also very stable. We show here that the other plasmids, especially the linear ones, are considerably more variable. Nearly all of the linear plasmids have undergone one or more substantial inter-plasmid rearrangements since their last common ancestor. In spite of these rearrangements and differences in plasmid contents, the overall gene complement of the different isolates has remained relatively constant.

Plasmid Conjugation in E. coli and Drug Resistance | Igwe ...

African Journals Online (AJOL)

This study aimed at determining the antibiotics susceptibility pattern of E. coli isolates claimed to be multidrug resistance using disc diffusion method. It also determined the presence of transferable resistance plasmids through conjugation and evaluated the medical significance of plasmid encoding E. coli and drug ...

Prevalência de Aeromonas ssp em fezes diarréicas de crianças menores de 5 anos de idade na cidade de Goiânia, Goiás, no biênio 1995 - 1996

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Idalina Thiomi Inumaru Nojimoto

1997-10-01

Full Text Available Foram analisadas 163 amostras de fezes de crianças com idade abaixo de 5 anos no período de 1995 a 1996, sendo 91 de fezes diarréicas e 72 de fezes não diarréicas. O material foi coletado em meio para transporte e submetido ao processo de enriquecimento a 4oC por 7 dias. Para o isolamento primário foi utilizado ágar amido ampicilina e incubado a 35oC por 18 a 24 horas. Foram isoladas 20 (21,9% das seguintes espécies: Aeromonas A. caviae (7,7%, A. salmonicida salmonicida (6,6%, A. sobria (4,3%, A. hydrophila (2,2% e Salmonicida achromogenes (1,1%. Nenhuma Aeromonas spp foi isolada dos 72 pacientes-controles. A susceptibilidade das amostras de Aeromonas spp aos antimicrobianos foi maior com a ciprofloxacina, diminuindo gradativamente com cloranfenicol, gentamicina, ampicilina e eritromicina.From 1995 through 1996, 163 fecal specimens of children aged under 5 years were analysed, 91 being from diarrhea feces and 72 without diarrhea. The material was collected in transport medium and submitted to the enrichment procedure at 4oC for 7 days. For the primary isolation starch ampicillin agar was used and incubated at 35oC for 18 to 24 hours. Twenty (20.9% from the following specimens were isolated: Aeromonas A. caviae (7.7%, A. salmonicida salmonicida (6.6%, A. sobria (4.3%, A. hydrophila (2.2% e Salmonicida achromogenes (1.1%. No Aeromonas spp was isolated from the 72 control subjects. The Aeromonas spp susceptibility to antimicrobian was greater with ciprofloxacin, being this susceptibility gradually diminished with chloranphenicol, gentamicin, ampicillin and erythromycin.

Mechanisms of Evolution in High-Consequence Drug Resistance Plasmids

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Susu He

2016-12-01

Full Text Available The dissemination of resistance among bacteria has been facilitated by the fact that resistance genes are usually located on a diverse and evolving set of transmissible plasmids. However, the mechanisms generating diversity and enabling adaptation within highly successful resistance plasmids have remained obscure, despite their profound clinical significance. To understand these mechanisms, we have performed a detailed analysis of the mobilome (the entire mobile genetic element content of a set of previously sequenced carbapenemase-producing Enterobacteriaceae (CPE from the National Institutes of Health Clinical Center. This analysis revealed that plasmid reorganizations occurring in the natural context of colonization of human hosts were overwhelmingly driven by genetic rearrangements carried out by replicative transposons working in concert with the process of homologous recombination. A more complete understanding of the molecular mechanisms and evolutionary forces driving rearrangements in resistance plasmids may lead to fundamentally new strategies to address the problem of antibiotic resistance.

Plasmids of Staphylococcus cohnii isolated from the intensive-care unit.

Science.gov (United States)

Szewczyk, E M; Rózalska, M; Cieślikowski, T; Nowak, T

2004-01-01

Numerous isolates of both subspecies of Staphylococcus cohnii were found in the environment of the intensive-care unit of a pediatric hospital. These isolates carried in their cells many plasmids, up to fourteen, of a wide range of sizes ( 56 kb). Striking was the occurrence of large plasmids not very common in staphylococci. These were present in > 80% of S. cohnii isolates. Fifty-two different plasmid profiles were found in 79 investigated isolates belonging to S. cohnii ssp. cohnii and S. cohnii ssp. urealyticus. Isolates similar in plasmid profiles were grouped in antibiotic-resistance clusters established for 9 antibiotics (gentamicin, ciprofloxacin, clindamycin, erythromycin, tetracycline, chloramphenicol, mupirocin, trimethoprim-sulfamethoxazole, vancomycin) using the method of unweighted pair group mathematical averages (UPGMA). Many isolates were multiresistant to antibiotics and produced bacteriocins.

Construction of Stable Fluorescent Reporter Plasmids for Use in Staphylococcus aureus

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Michelle D. Rodriguez

2017-12-01

Full Text Available Here, the genes encoding three different fluorescent proteins were cloned into the stably maintained Staphylococcus aureus shuttle vector pKK30. The resulting plasmids were transformed into two S. aureus strains; SH1000 and RN4220. Stability assays illustrated that the three recombinant plasmids retained near 100% maintenance in vitro for 160 generations. S. aureus strain SH1000 expressing green fluorescent protein was then inoculated in an ovine model and in vivo stability for 6 days was demonstrated. In essence, these reporter plasmids represent a useful set of tools for dynamic imaging studies in S. aureus. These three reporter plasmids are available through BEI Resources.

Construction of Stable Fluorescent Reporter Plasmids for Use in Staphylococcus aureus.

Science.gov (United States)

Rodriguez, Michelle D; Paul, Zubin; Wood, Charles E; Rice, Kelly C; Triplett, Eric W

2017-01-01

Here, the genes encoding three different fluorescent proteins were cloned into the stably maintained Staphylococcus aureus shuttle vector pKK30. The resulting plasmids were transformed into two S. aureus strains; SH1000 and RN4220. Stability assays illustrated that the three recombinant plasmids retained near 100% maintenance in vitro for 160 generations. S. aureus strain SH1000 expressing green fluorescent protein was then inoculated in an ovine model and in vivo stability for 6 days was demonstrated. In essence, these reporter plasmids represent a useful set of tools for dynamic imaging studies in S. aureus . These three reporter plasmids are available through BEI Resources.

Fast and efficient three-step target-specific curing of a virulence plasmid in Salmonella enterica.

Science.gov (United States)

de Moraes, Marcos H; Teplitski, Max

2015-12-01

Virulence plasmids borne by serovars of Salmonella enterica carry genes involved in its pathogenicity, as well as other functions. Characterization of phenotypes associated with virulence plasmids requires a system for efficiently curing strains of their virulence plasmids. Here, we developed a 3-step protocol for targeted curing of virulence plasmids. The protocol involves insertion of an I-SecI restriction site linked to an antibiotic resistance gene into the target plasmid using λ-Red mutagenesis, followed by the transformation with a temperature-sensitive auxiliary plasmid which carries I-SecI nuclease expressed from a tetracycline-inducible promoter. Finally, the auxiliary plasmid is removed by incubation at 42 °C and the plasmid-less strains are verified on antibiotic-containing media. This method is fast and very efficient: over 90 % of recovered colonies lacked their virulence plasmid.

Quantification bias caused by plasmid DNA conformation in quantitative real-time PCR assay.

Science.gov (United States)

Lin, Chih-Hui; Chen, Yu-Chieh; Pan, Tzu-Ming

2011-01-01

Quantitative real-time PCR (qPCR) is the gold standard for the quantification of specific nucleic acid sequences. However, a serious concern has been revealed in a recent report: supercoiled plasmid standards cause significant over-estimation in qPCR quantification. In this study, we investigated the effect of plasmid DNA conformation on the quantification of DNA and the efficiency of qPCR. Our results suggest that plasmid DNA conformation has significant impact on the accuracy of absolute quantification by qPCR. DNA standard curves shifted significantly among plasmid standards with different DNA conformations. Moreover, the choice of DNA measurement method and plasmid DNA conformation may also contribute to the measurement error of DNA standard curves. Due to the multiple effects of plasmid DNA conformation on the accuracy of qPCR, efforts should be made to assure the highest consistency of plasmid standards for qPCR. Thus, we suggest that the conformation, preparation, quantification, purification, handling, and storage of standard plasmid DNA should be described and defined in the Minimum Information for Publication of Quantitative Real-Time PCR Experiments (MIQE) to assure the reproducibility and accuracy of qPCR absolute quantification.

Broad host range plasmids can invade an unexpectedly diverse fraction of a soil bacterial community

DEFF Research Database (Denmark)

Klümper, Uli; Riber, Leise; Dechesne, Arnaud

2014-01-01

and Actinobacteria suggests that inter-Gram plasmid transfer of IncP-1 and IncPromA-type plasmids is a frequent phenomenon. While the plasmid receiving fractions of the community were both plasmid- and donor- dependent, we identified a core super-permissive fraction that could take up different plasmids from diverse...

Plasmids in Vibrio parahemolyticus strains isolated in Japan and Bangladesh with special reference to different distributions.

Science.gov (United States)

Arai, T; Ando, T; Kusakabe, A; Ullah, M A

1983-01-01

We surveyed plasmids in naturally occurring Vibrio parahemolyticus strains isolated in Japan and Bangladesh. Among the strains isolated in Japan, about half of the strains isolated from stools of patients of domestic diarrhea outbreaks as well as of travelers returning from East Asia were found to have plasmids, but no strains from foods had plasmids. In contrast, among the strains isolated in Bangladesh, none of the four strains isolated from patients had plasmids, but two out of eight strains isolated from water had plasmids, suggesting that plasmids are common in strains from the water in Bangladesh. All plasmids so far reported in V. parahemolyticus were detected in strains isolated from stools of patients. Incidences of plasmids in this organism were not so high in either area. In Japan, all plasmids were detected in strains from human intestines at 37 C, but in Bangladesh, where the temperature is around 30-40 C, the plasmids were detected in strains from the natural environment. These results suggested the possibility that these plasmids can come from different bacteria under rather high temperatures and that incidences of plasmids are influenced by the incidences of plasmids in bacteria present in the vicinity of V. parahemolyticus strains. None of these plasmids were found to have any relation to the biological characters tested.

Quorum sensing signals are produced by Aeromonas salmonicida and quorum sensing inhibitors can reduce production of a potential virulence factor

DEFF Research Database (Denmark)

Rasch, Maria; Kastbjerg, Vicky Gaedt; Bruhn, Jesper Bartholin

2007-01-01

Many pathogens control production of virulence factors by self-produced signals in a process called quorum sensing (QS). We demonstrate that acyl homoserine lactone (AHL) signals, which enable bacteria to express certain phenotypes in relation to cell density, are produced by a wide spectrum...... of Aeromonas salmonicida strains. All 31 typical strains were AHL producers as were 21 of 26 atypical strains, but on a strain population basis, production of virulence factors such as protease, lipase, A-layer or pigment did not correlate with the production and accumulation of AHLs in the growth medium...... of Aeromonas salmonicida. The most efficient compound N-(heptylsulfanylacetyl)-L-homoserine lactone (HepS-AHL), reduced protease production by a factor of 10. Five extracellular proteases were detected on gelatin-containing sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) gels and 3...

Characterization of Plasmid pPO1 from the Hyperacidophile Picrophilus oshimae

Directory of Open Access Journals (Sweden)

Angel Angelov

2011-01-01

Full Text Available Picrophilus oshimae and Picrophilus torridus are free-living, moderately thermophilic and acidophilic organisms from the lineage of Euryarchaeota. With a pH optimum of growth at pH 0.7 and the ability to even withstand molar concentrations of sulphuric acid, these organisms represent the most extreme acidophiles known. So far, nothing is known about plasmid biology in these hyperacidophiles. Also, there are no genetic tools available for this genus. We have mobilized the 7.6 Kbp plasmid from P. oshimae in E. coli by introducing origin-containing transposons and described the plasmid in terms of its nucleotide sequence, copy number in the native host, mode of replication, and transcriptional start sites of the encoded ORFs. Plasmid pPO1 may encode a restriction/modification system in addition to its replication functions. The information gained from the pPO1 plasmid may prove useful in developing a cloning system for this group of extreme acidophiles.

Sequential acquisition of R-plasmids in vivo by Salmonella typhimurium.

Science.gov (United States)

Platt, D J; Sommerville, J S; Gribben, J

1984-01-01

Salmonella typhimurium, resistant only to trimethoprim and sulphamethoxazole, was isolated from the faeces and blood of a chronic alcoholic patient in acute renal failure. The isolates harboured an 18 Md non-conjugative plasmid. He was dialysed peritoneally and treated with ampicillin; four days later there was no clinical improvement and his peritoneal dialysis fluid (PDF) had become infected. Salm. typhimurium was isolated from faeces and PDF. Both isolates were additionally resistant to ampicillin and contained two plasmids (55 Md and 18 Md). Therapy was changed to chloramphenicol and gentamicin was added to the PDF. Two weeks later Salm. typhimurium was again isolated from PDF and faeces. The PDF isolate was unchanged but 4% of the colonies isolated from this faecal specimen were resistant to chloramphenicol and had acquired an additional 62 Md plasmid. From all PDF and faecal specimens two different strains of Escherichia coli and one strain of Klebsiella pneumoniae were isolated which contained plasmids indistinguishable, on the basis of molecular weight and transferable resistance markers, from those acquired by Salm. typhimurium. The transferability of these plasmids in vitro to E. coli K12 and to the patient's initial Salm. typhimurium was studied and the results discussed.

Positive correlation between Aeromonas salmonicida vaccine antigen concentration and protection in vaccinated rainbow trout Oncorhynchus mykiss evaluated by a tail fin infection model

DEFF Research Database (Denmark)

Marana, M. H.; Skov, J.; Chettri, Jiwan Kumar

2017-01-01

Rainbow trout, Oncorhynchus mykiss (Walbaum), are able to raise a protective immune response against Aeromonas salmonicida subsp. salmonicida (AS) following injection vaccination with commercial vaccines containing formalin-killed bacteria, but the protection is often suboptimal under Danish...... mariculture conditions. We elucidated whether protection can be improved by increasing the concentration of antigen (formalin-killed bacteria) in the vaccine. Rainbow trout juveniles were vaccinated by intraperitoneal (i.p.) injection with a bacterin of Aeromonas salmonicida subsp. salmonicida strain 090710...... bacteria. The infection method proved to be efficient and could differentiate efficacies of different vaccines. It was shown that protection and antibody production in exposed fish were positively correlated to the AS antigen concentration in the vaccine....

Characterization of plasmids in a human clinical strain of Lactococcus garvieae.

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Mónica Aguado-Urda

Full Text Available The present work describes the molecular characterization of five circular plasmids found in the human clinical strain Lactococcus garvieae 21881. The plasmids were designated pGL1-pGL5, with molecular sizes of 4,536 bp, 4,572 bp, 12,948 bp, 14,006 bp and 68,798 bp, respectively. Based on detailed sequence analysis, some of these plasmids appear to be mosaics composed of DNA obtained by modular exchange between different species of lactic acid bacteria. Based on sequence data and the derived presence of certain genes and proteins, the plasmid pGL2 appears to replicate via a rolling-circle mechanism, while the other four plasmids appear to belong to the group of lactococcal theta-type replicons. The plasmids pGL1, pGL2 and pGL5 encode putative proteins related with bacteriocin synthesis and bacteriocin secretion and immunity. The plasmid pGL5 harbors genes (txn, orf5 and orf25 encoding proteins that could be considered putative virulence factors. The gene txn encodes a protein with an enzymatic domain corresponding to the family actin-ADP-ribosyltransferases toxins, which are known to play a key role in pathogenesis of a variety of bacterial pathogens. The genes orf5 and orf25 encode two putative surface proteins containing the cell wall-sorting motif LPXTG, with mucin-binding and collagen-binding protein domains, respectively. These proteins could be involved in the adherence of L. garvieae to mucus from the intestine, facilitating further interaction with intestinal epithelial cells and to collagenous tissues such as the collagen-rich heart valves. To our knowledge, this is the first report on the characterization of plasmids in a human clinical strain of this pathogen.

Broad-Host-Range IncP-1 plasmids and their resistance potential

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Magdalena ePopowska

2013-03-01

Full Text Available The plasmids of the incompatibility group IncP-1, also called IncP, as extrachromosomal genetic elements can transfer and replicate virtually in all Gram-negative bacteria. They are composed of backbone genes that encode a variety of essential functions and accessory genes that have implications for human health and environmental bioremediation. Broad-host-range IncP plasmids are known to spread genes between distinct phylogenetic groups of bacteria. These genes often code for resistances to a broad spectrum of antibiotics, heavy metals and quaternary ammonium compounds used as disinfectants. The backbone of these plasmids carries modules that enable them to effectively replicate, move to a new host via conjugative transfer and to be stably maintained in bacterial cells. The adaptive, resistance and virulence genes are mainly located on mobile genetic elements integrated between the functional plasmid backbone modules. Environmental studies have demonstrated the wide distribution of IncP-like replicons in manure, soils and wastewater treatment plants. They also are present in strains of pathogenic or opportunistic bacteria, which can be a cause for concern, because they may encode multiresistance. Their broad distribution suggests that IncP plasmids play a crucial role in bacterial adaptation by utilizing horizontal gene transfer. This review summarizes the variety of genetic information and physiological functions carried by IncP plasmids, which can contribute to the spread of antibiotic and heavy metal resistance while also mediating the process of bioremediation of pollutants. Due to the location of the resistance genes on plasmids with a broad host range and the presence of transposons carrying these genes it seems that the spread of these genes would be possible and quite hazardous in infection control. Future studies are required to determine the level of risk of the spread of resistance genes located on these plasmids.

Non-additive costs and interactions alter the competitive dynamics of co-occurring ecologically distinct plasmids.

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Morton, Elise R; Platt, Thomas G; Fuqua, Clay; Bever, James D

2014-03-22

Plasmids play an important role in shaping bacterial evolution and adaptation to heterogeneous environments. As modular genetic elements that are often conjugative, the selective pressures that act on plasmid-borne genes are distinct from those that act on the chromosome. Many bacteria are co-infected by multiple plasmids that impart niche-specific phenotypes. Thus, in addition to host-plasmid dynamics, interactions between co-infecting plasmids are likely to be important drivers of plasmid population dynamics, evolution and ecology. Agrobacterium tumefaciens is a facultative plant pathogen that commonly harbours two distinct megaplasmids. Virulence depends on the presence of the tumour-inducing (Ti) plasmid, with benefits that are primarily restricted to the disease environment. Here, we demonstrate that a second megaplasmid, the At plasmid, confers a competitive advantage in the rhizosphere. To assess the individual and interactive costs of these plasmids, we generated four isogenic derivatives: plasmidless, pAt only, pTi only and pAtpTi, and performed pairwise competitions under carbon-limiting conditions. These studies reveal a low cost to the virulence plasmid when outside of the disease environment, and a strikingly high cost to the At plasmid. In addition, the costs of pAt and pTi in the same host were significantly lower than predicted based on single plasmid costs, signifying the first demonstration of non-additivity between naturally occurring co-resident plasmids. Based on these empirically demonstrated costs and benefits, we developed a resource-consumer model to generate predictions about the frequencies of these genotypes in relevant environments, showing that non-additivity between co-residing plasmids allows for their stable coexistence across environments.

Reconstructing the complex evolutionary history of mobile plasmids in red algal genomes

Science.gov (United States)

Lee, JunMo; Kim, Kyeong Mi; Yang, Eun Chan; Miller, Kathy Ann; Boo, Sung Min; Bhattacharya, Debashish; Yoon, Hwan Su

2016-01-01

The integration of foreign DNA into algal and plant plastid genomes is a rare event, with only a few known examples of horizontal gene transfer (HGT). Plasmids, which are well-studied drivers of HGT in prokaryotes, have been reported previously in red algae (Rhodophyta). However, the distribution of these mobile DNA elements and their sites of integration into the plastid (ptDNA), mitochondrial (mtDNA), and nuclear genomes of Rhodophyta remain unknown. Here we reconstructed the complex evolutionary history of plasmid-derived DNAs in red algae. Comparative analysis of 21 rhodophyte ptDNAs, including new genome data for 5 species, turned up 22 plasmid-derived open reading frames (ORFs) that showed syntenic and copy number variation among species, but were conserved within different individuals in three lineages. Several plasmid-derived homologs were found not only in ptDNA but also in mtDNA and in the nuclear genome of green plants, stramenopiles, and rhizarians. Phylogenetic and plasmid-derived ORF analyses showed that the majority of plasmid DNAs originated within red algae, whereas others were derived from cyanobacteria, other bacteria, and viruses. Our results elucidate the evolution of plasmid DNAs in red algae and suggest that they spread as parasitic genetic elements. This hypothesis is consistent with their sporadic distribution within Rhodophyta. PMID:27030297

Epidemiology of Danish Aeromonas salmonicida subsp salmonicida in Fish Farms Using Whole Genome Sequencing

DEFF Research Database (Denmark)

Bartkova, Simona; Leekitcharoenphon, Pimlapas; Aarestrup, Frank Møller

2017-01-01

transmission of the bacterium could have been from seawater to freshwater or vice versa, and most minor clades include a mixture of strains from different fresh- and seawater farms. Genomic variation of A. salmonicida subsp. salmonicida mostly appeared to be associated with their plasmids and plasmid encoded...

Plasmid-derived DNA Strand Displacement Gates for Implementing Chemical Reaction Networks.

Science.gov (United States)

Chen, Yuan-Jyue; Rao, Sundipta D; Seelig, Georg

2015-11-25

DNA nanotechnology requires large amounts of highly pure DNA as an engineering material. Plasmid DNA could meet this need since it is replicated with high fidelity, is readily amplified through bacterial culture and can be stored indefinitely in the form of bacterial glycerol stocks. However, the double-stranded nature of plasmid DNA has so far hindered its efficient use for construction of DNA nanostructures or devices that typically contain single-stranded or branched domains. In recent work, it was found that nicked double stranded DNA (ndsDNA) strand displacement gates could be sourced from plasmid DNA. The following is a protocol that details how these ndsDNA gates can be efficiently encoded in plasmids and can be derived from the plasmids through a small number of enzymatic processing steps. Also given is a protocol for testing ndsDNA gates using fluorescence kinetics measurements. NdsDNA gates can be used to implement arbitrary chemical reaction networks (CRNs) and thus provide a pathway towards the use of the CRN formalism as a prescriptive molecular programming language. To demonstrate this technology, a multi-step reaction cascade with catalytic kinetics is constructed. Further it is shown that plasmid-derived components perform better than identical components assembled from synthetic DNA.

A DNA biosensor for molecular diagnosis of Aeromonas hydrophila using zinc sulfide nanospheres

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M. Negahdary

2017-07-01

Full Text Available Today, identification of pathogenic bacteria using modern and accurate methods is inevitable. Integration in electrochemical measurements with nanotechnology has led to the design of efficient and sensitive DNA biosensors against bacterial agents. Here, efforts were made to detect Aeromonas hydrophila using aptamers as probes and zinc sulfide (ZnS nanospheres as signal enhancers and electron transfer facilitators. After modification of the working electrode area (in a screen-printed electrode with ZnS nanospheres through electrodeposition, the coated surface of a modified electrode with ZnS nanospheres was investigated through scanning electron microscopy (SEM. The size of synthesized ZnS nanospheres was estimated at about 20–50 nm and their shape was in the form of porous plates in microscopic observations. All electrochemical measurements were performed using cyclic voltammetry (CV, electrochemical impedance spectroscopy (EIS, and constant potential amperometry (CPA techniques. The designed DNA biosensor was able to detect deoxyribonucleic acid (DNA of Aeromonas hydrophila in the range 1.0  ×  10−4 to 1.0  ×  10−9 mol L−1; the limit of detection (LOD in this study was 1  ×  10−13 mol L−1. This DNA biosensor showed satisfactory thermal and pH stability. Reproducibility for this DNA biosensor was measured and the relative standard deviation (RSD of the performance of this DNA biosensor was calculated as 5 % during 42 days.

Strategies and approaches in plasmidome studies—uncovering plasmid diversity disregarding of linear elements?

Science.gov (United States)

Dib, Julián R.; Wagenknecht, Martin; Farías, María E.; Meinhardt, Friedhelm

2015-01-01

The term plasmid was originally coined for circular, extrachromosomal genetic elements. Today, plasmids are widely recognized not only as important factors facilitating genome restructuring but also as vehicles for the dissemination of beneficial characters within bacterial communities. Plasmid diversity has been uncovered by means of culture-dependent or -independent approaches, such as endogenous or exogenous plasmid isolation as well as PCR-based detection or transposon-aided capture, respectively. High-throughput-sequencing made possible to cover total plasmid populations in a given environment, i.e., the plasmidome, and allowed to address the quality and significance of self-replicating genetic elements. Since such efforts were and still are rather restricted to circular molecules, here we put equal emphasis on the linear plasmids which—despite their frequent occurrence in a large number of bacteria—are largely neglected in prevalent plasmidome conceptions. PMID:26074886

Natural plasmid transformation in a high-frequency-of transformation marine Vibrio strain

International Nuclear Information System (INIS)

Frischer, M.E.; Thurmond, J.M.; Paul, J.H.

1990-01-01

The estuarine bacterium Vibrio strain DI-9 has been shown to be naturally transformable with both broad host range plasmid multimers and homologous chromosomal DNA at average frequencies of 3.5 x 10 -9 and 3.4 x 10 -7 transformants per recipient, respectively. Growth of plasmid transformants in nonselective medium resulted in cured strains that transformed 6 to 42,857 times more frequently than the parental strain, depending on the type of transforming DNA. These high-frequency-of-transformation (HfT) strains were transformed at frequencies ranging from 1.1 x 10 -8 to 1.3 x 10 -4 transformants per recipient with plasmid DNA and at an average frequency of 8.3 x 10 -5 transformants per recipient with homologous chromosomal DNA. The highest transformation frequencies were observed by using multimers of an R1162 derivative carrying the transposon Tn5 (pQSR50). Probing of total DNA preparations from one of the cured strains demonstrated that no plasmid DNA remained in the cured strains which may have provided homology to the transforming DNA. All transformants and cured strains could be differentiated from the parental strains by colony morphology. DNA binding studies indicated that late-log-phase HfT strains bound [ 3 H]bacteriophage lambda DNA 2.1 times more rapidly than the parental strain. These results suggest that the original plasmid transformation event of strain DI-9 was the result of uptake and expression of plasmid DNA by a competent mutant (HfT strain). Additionally, it was found that a strain of Vibrio parahaemolyticus, USFS 3420, could be naturally transformed with plasmid DNA. Natural plasmid transformation by high-transforming mutants may be a means of plasmid acquisition by natural aquatic bacterial populations

Repair promoted by plasmid pKM101 is different from SOS repair

International Nuclear Information System (INIS)

Goze, A.; Devoret, R.

1979-01-01

In E. coli K12 bacteria carrying plasmid pKM101, prophage lambda was induced at UV doses higher than in plasmid-less parental bacteria. UV-induced reactivation per se was less effective. Bacteria with pKM101 showed no alteration in their division cycle. Plasmid PKM101 coded for a constitutive error-prone repair different from the inducible error-prone repair called SOS repair. Plasmid pKM101 protected E. coli bacteria from UV damage but slightly sensitized them to X-ray lesions. Protection against UV damage was effective in mutant bacteria deficient in DNA excision-repair provided that the recA, lexA and uvrE genes were functional. Survival of phages lambda and S13 after UV irradiation was enhanced in bacteria carrying plasmid pKM101; phage lambda mutagenesis was also increased. Plasmid pKM101 repaired potentially lethal DNA lesions, although Wild-type DNA sequences may not necessarily be restored; hence the mutations observed are the traces of the original DNA lesions. (Auth.)

sugE: A gene involved in tributyltin (TBT) resistance of Aeromonas molluscorum Av27.

Science.gov (United States)

Cruz, Andreia; Micaelo, Nuno; Félix, Vitor; Song, Jun-Young; Kitamura, Shin-Ichi; Suzuki, Satoru; Mendo, Sónia

2013-01-01

The mechanism of bacterial resistance to tributyltin (TBT) is still unclear. The results herein presented contribute to clarify that mechanism in the TBT-resistant bacterium Aeromonas molluscorum Av27. We have identified and cloned a new gene that is involved in TBT resistance in this strain. The gene is highly homologous (84%) to the Aeromonas hydrophila-sugE gene belonging to the small multidrug resistance gene family (SMR), which includes genes involved in the transport of lipophilic drugs. In Av27, expression of the Av27-sugE was observed at the early logarithmic growth phase in the presence of a high TBT concentration (500 μM), thus suggesting the contribution of this gene for TBT resistance. E. coli cells transformed with Av27-sugE become resistant to ethidium bromide (EtBr), chloramphenicol (CP) and tetracycline (TE), besides TBT. According to the Moriguchi logP (miLogP) values, EtBr, CP and TE have similar properties and are substrates for the sugE-efflux system. Despite the different miLogP of TBT, E. coli cells transformed with Av27-sugE become resistant to this compound. So it seems that TBT is also a substrate for the SugE protein. The modelling studies performed also support this hypothesis. The data herein presented clearly indicate that sugE is involved in TBT resistance of this bacterium.

The complete sequence and comparative analysis of a multidrug- resistance and virulence multireplicon IncFII plasmid pEC302/04 from an extraintestinal pathogenic Escherichia coli EC302/04 indicate extensive diversity of IncFII plasmids

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Wing Sze eHo

2016-01-01

Full Text Available Extraintestinal pathogenic Escherichia coli (ExPEC that causes extraintestinal infections often harbor plasmids encoding fitness traits such as resistance and virulence determinants that are of clinical importance. We determined the complete nucleotide sequence of plasmid pEC302/04 from a multidrug-resistant E. coli EC302/04 which was isolated from the tracheal aspirate of a patient in Malaysia. In addition, we also performed comparative sequence analyses of 18 related IncFIIA plasmids to determine the phylogenetic relationship and diversity of these plasmids. The 140,232 bp pEC302/04 is a multireplicon plasmid that bears three replication systems (FII, FIA and FIB with subtype of F2:A1:B1. The plasmid is self-transmissible with a complete transfer region. pEC302/04 also carries antibiotic resistance genes such as blaTEM-1 and a class I integron containing sul1, cml and aadA resistance genes, conferring multidrug resistance (MDR to its host, E. coli EC302/04. Besides, two iron acquisition systems (SitABCD and IutA-IucABCD which are the conserved virulence determinants of ExPEC-colicin V or B and M (ColV/ColBM-producing plasmids were identified in pEC302/04. Multiple toxin-antitoxin (TA-based addiction systems (i.e., PemI/PemK, VagC/VagD, CcdA/CcdB, and Hok/Sok and a plasmid partitioning system, ParAB and PsiAB, which are important for plasmid maintenance were also found.Comparative plasmid analysis revealed only one conserved gene, the repA1 as the core genome, showing that there is an extensive diversity among the IncFIIA plasmids. The phylogenetic relationship of 18 IncF plasmids based on the core regions revealed that ColV/ColBM-plasmids and non-ColV/ColBM plasmids were separated into two distinct groups. These plasmids, which carry highly diverse genetic contents, are also mosaic in nature. The atypical combination of genetic materials, i.e., the MDR- and ColV/ColBM-plasmid-virulence encoding regions in a single ExPEC plasmid is rare but of

The Complete Sequence and Comparative Analysis of a Multidrug-Resistance and Virulence Multireplicon IncFII Plasmid pEC302/04 from an Extraintestinal Pathogenic Escherichia coli EC302/04 Indicate Extensive Diversity of IncFII Plasmids.

Science.gov (United States)

Ho, Wing Sze; Yap, Kien-Pong; Yeo, Chew Chieng; Rajasekaram, Ganeswrie; Thong, Kwai Lin

2015-01-01

Extraintestinal pathogenic Escherichia coli (ExPEC) that causes extraintestinal infections often harbor plasmids encoding fitness traits such as resistance and virulence determinants that are of clinical importance. We determined the complete nucleotide sequence of plasmid pEC302/04 from a multidrug-resistant E. coli EC302/04 which was isolated from the tracheal aspirate of a patient in Malaysia. In addition, we also performed comparative sequence analyses of 18 related IncFIIA plasmids to determine the phylogenetic relationship and diversity of these plasmids. The 140,232 bp pEC302/04 is a multireplicon plasmid that bears three replication systems (FII, FIA, and FIB) with subtype of F2:A1:B1. The plasmid is self-transmissible with a complete transfer region. pEC302/04 also carries antibiotic resistance genes such as bla TEM-1 and a class I integron containing sul1, cml and aadA resistance genes, conferring multidrug resistance (MDR) to its host, E. coli EC302/04. Besides, two iron acquisition systems (SitABCD and IutA-IucABCD) which are the conserved virulence determinants of ExPEC-colicin V or B and M (ColV/ColBM)-producing plasmids were identified in pEC302/04. Multiple toxin-antitoxin (TA)-based addiction systems (i.e., PemI/PemK, VagC/VagD, CcdA/CcdB, and Hok/Sok) and a plasmid partitioning system, ParAB, and PsiAB, which are important for plasmid maintenance were also found. Comparative plasmid analysis revealed only one conserved gene, the repA1 as the core genome, showing that there is an extensive diversity among the IncFIIA plasmids. The phylogenetic relationship of 18 IncF plasmids based on the core regions revealed that ColV/ColBM-plasmids and non-ColV/ColBM plasmids were separated into two distinct groups. These plasmids, which carry highly diverse genetic contents, are also mosaic in nature. The atypical combination of genetic materials, i.e., the MDR- and ColV/ColBM-plasmid-virulence encoding regions in a single ExPEC plasmid is rare but of clinical

Novel archaeal plasmid pAH1 and its interactions with the lipothrixvirus AFV1

DEFF Research Database (Denmark)

Basta, Tamara; Smyth, John; Forterre, Patrick

2009-01-01

. Although nucleotide sequence comparisons revealed extensive intergenomic exchange during the evolution of archaeal conjugative plasmids, pAH1 was shown to be stably maintained suggesting that the host system is suitable for studying plasmid-virus interactions. AFV1 infection and propagation leads to a loss...... of the circular form of pAH1 and this effect correlates positively with the increase in the intracellular quantity of AFV1 DNA. We infer that the virus inhibits plasmid replication since no pAH1 degradation was observed. This mechanism of archaeal viral inhibition of plasmid propagation is not observed...... in bacteria where relevant bacteriophages either are dependent on a conjugative plasmid for successful infection or are excluded by a resident plasmid....

Antibiotic resistence of Aeromonas hydrophila isolated from Piaractus mesopotamicus (Holmberg, 1887) and Oreochromis niloticus (Linnaeus, 1758)

OpenAIRE

Belém-Costa,Andréa; Cyrino,José Eurico Possebon

2006-01-01

One of the most important problems involving treatments with antibiotics against Aeromonas hydrophila isolated from fishes is that antibiotic resistance develops readily. The antimicrobial activity of chemotherapeutants in isolates from pacu Piaractus mesopotamicus (Holmberg, 1887) and tilapia Oreochromis niloticus (Linnaeus, 1758) was tested by the Kirby-Bauer disk method, over Mueller-Hinton surface agar previously inoculated with 100 µL of bacterial suspensions. After regular incubation, i...

Prevalence and diversity of Aeromonas and Vibrio spp. in coastal waters of Southern Italy

DEFF Research Database (Denmark)

Dumontet, S.; Krovacek, K.; Svenson, S.B.

2000-01-01

% of samples were positive for Vibrio spp. It was interesting to note that 38% of the positive stations for both Aeromonas and Vibrio spp. showed a fecal coliform contamination of water at ... coliforms) do not always satisfactorily reflect the hygienic quality of water. The presence of Vibrionaceae on copepods was also investigated. Copepods were sampled at a station located inside the harbour of the city of Naples and were found contaminated by V. cholerae non-Ol, V. alginolyticus, V. fluvialis...

DIFFERENTIATION OF AEROMONAS ISOLATES OBTAINED FROM DRINKING WATER DISTRIBUTION SYSTEM USING MATRIX-ASSISTED LASER DESCRIPTION/IONIZATION-MASS SPECTROMETRY (MALDI-MS)

Science.gov (United States)

The genus Aeromonas is one of several medically significant genera that have gained prominence due to their evolving taxonomy and controversial role in human diseases. In this study, matrix-assisted laser desorption/ionization-mass spectrometry (MALDI-MS) was used to analyze the...

Comparative metagenomic analysis of plasmid encoded functions in the human gut microbiome

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Marchesi Julian R

2010-01-01

Full Text Available Abstract Background Little is known regarding the pool of mobile genetic elements associated with the human gut microbiome. In this study we employed the culture independent TRACA system to isolate novel plasmids from the human gut microbiota, and a comparative metagenomic analysis to investigate the distribution and relative abundance of functions encoded by these plasmids in the human gut microbiome. Results Novel plasmids were acquired from the human gut microbiome, and homologous nucleotide sequences with high identity (>90% to two plasmids (pTRACA10 and pTRACA22 were identified in the multiple human gut microbiomes analysed here. However, no homologous nucleotide sequences to these plasmids were identified in the murine gut or environmental metagenomes. Functions encoded by the plasmids pTRACA10 and pTRACA22 were found to be more prevalent in the human gut microbiome when compared to microbial communities from other environments. Among the most prevalent functions identified was a putative RelBE toxin-antitoxin (TA addiction module, and subsequent analysis revealed that this was most closely related to putative TA modules from gut associated bacteria belonging to the Firmicutes. A broad phylogenetic distribution of RelE toxin genes was observed in gut associated bacterial species (Firmicutes, Bacteroidetes, Actinobacteria and Proteobacteria, but no RelE homologues were identified in gut associated archaeal species. We also provide indirect evidence for the horizontal transfer of these genes between bacterial species belonging to disparate phylogenetic divisions, namely Gram negative Proteobacteria and Gram positive species from the Firmicutes division. Conclusions The application of a culture independent system to capture novel plasmids from the human gut mobile metagenome, coupled with subsequent comparative metagenomic analysis, highlighted the unexpected prevalence of plasmid encoded functions in the gut microbial ecosystem. In

POTENSI TUMBUHAN BANGKAL (Nauclea Orientalis UNTUK PENGENDALIAN BAKTERI Aeromonas Hydrophila (POTENTIAL PLANT BANGKAL (Nauclea orientalis FOR CONTROL Aeromonas Hydrophila

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Siti Aisiah

2017-02-01

Full Text Available Tujuan penelitian ini adalah didapatkan metode pengendalian penyakit yang disebabkan oleh bakteri Aeromonas hydrophila pada budi daya ikan yang ramah lingkungan. Dalam penelitian ini dilakukan uji sensitivitas terhadap bakteri A. hydrophila, uji minimal konsentrasi menghambat  bakteri A. hydrophila (uji MIC dan uji toksisitas terhadap ikan nila. Rancangan  yang digunakan untuk  uji toksisitas  adalah rancangan acak lengkap (RAL, dengan 4 perlakuan yaitu A  = Ikan disuntik dengan ekstrak bangkal konsentrasi 20%, B  = Ikan disuntik dengan ekstrak bangkal konsentrasi 40%,  C  = Ikan disuntik dengan ekstrak bangkal konsentrasi 80%, dan D  = Kontrol (ikan tidak disuntik, diulang sebanyak 3 kali. Perlakuan ini didapat dari hasil uji sensitivitas antibakteri bangkal yang mempunyai daya hambat dan daya bunuh paling besar terhadap bakteri A. hydrophila yaitu ekstrak daun bangkal dengan pelarut akuades. Pengujian MIC menunjukkan bahwa ekstrak bangkal-akuades memiliki daya hambat minimal  20 % terhadap aktivitas bakteri A. hydrophila. Hasil uji toksisitas yang dilakukan terhadap ikan nila dengan konsentrasi 20%, 40% dan 80%  mortalitas ikan nila dibawah 50 %. Pengamatan hematologis yaitu eretrosit, leokosit, plasma darah, hematokrit dan leokokrit pada masing-masing perlakuan sebagian besar masih berada dalam kisaran yang normal. Parameter kualitas air yaitu, kadar oksigen terlarut,  pH, amoniak, CO2 dan suhu masih dapat mendukung kehidupan normal ikan nila. The purpose of this study was obtained method of controlling diseases caused by Aeromonas hydrophila in fish farming is environmentally friendly. In this study the sensitivity of the test  A. hydrophila, a minimum test konsentari inhibiting A. hydrophila (MIC test and toxicity test on  tilapia. The design used for toxicity tests is completely randomized design with 4 treatments it A = Fish injected with extracts bangkal concentration of 20 %,  B = Fish injected with extracts bangkal

Plant-inducible virulence promoter of the Agrobacterium tumefaciens Ti plasmid

NARCIS (Netherlands)

Okker, Robert J.H.; Spaink, Herman; Hille, Jacques; Brussel, Ton A.N. van; Lugtenberg, Ben; Schilperoort, Rob A.

1984-01-01

Agrobacterium tumefaciens is the causative agent of crown gall, a plant tumour that can arise on most species of dicotyledonous plants. The tumour-inducing capacity of the bacterium requires the presence of a large plasmid, designated the Ti plasmid, which itself contains two regions essential for

Genetic characterization of blaNDM-harboring plasmids in carbapenem-resistant Escherichia coli from Myanmar.

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Yo Sugawara

Full Text Available The bacterial enzyme New Delhi metallo-β-lactamase hydrolyzes almost all β-lactam antibiotics, including carbapenems, which are drugs of last resort for severe bacterial infections. The spread of carbapenem-resistant Enterobacteriaceae that carry the New Delhi metallo-β-lactamase gene, blaNDM, poses a serious threat to public health. In this study, we genetically characterized eight carbapenem-resistant Escherichia coli isolates from a tertiary care hospital in Yangon, Myanmar. The eight isolates belonged to five multilocus-sequence types and harbored multiple antimicrobial-resistance genes, resulting in resistance against nearly all of the antimicrobial agents tested, except colistin and fosfomycin. Nine plasmids harboring blaNDM genes were identified from these isolates. Multiple blaNDM genes were found in the distinct Inc-replicon types of the following plasmids: an IncA/C2 plasmid harboring blaNDM-1 (n = 1, IncX3 plasmids harboring blaNDM-4 (n = 2 or blaNDM-7 (n = 1, IncFII plasmids harboring blaNDM-4 (n = 1 or blaNDM-5 (n = 3, and a multireplicon F plasmid harboring blaNDM-5 (n = 1. Comparative analysis highlighted the diversity of the blaNDM-harboring plasmids and their distinct characteristics, which depended on plasmid replicon types. The results indicate circulation of phylogenetically distinct strains of carbapenem-resistant E. coli with various plasmids harboring blaNDM genes in the hospital.

Evaluating virulence of waterborne and clinical Aeromonas isolates using gene expression and mortality in neonatal mice followed by assessing cell culture’s ability to predict virulence based on transcriptional response

Energy Technology Data Exchange (ETDEWEB)

Hayes, S L; Rodgers, M R; Lye, D J; Stelma, G N; McKinstry, Craig A.; Malard, Joel M.; Vesper, Sephen J.

2007-10-01

Aims: To assess the virulence of Aeromonas spp. using two models, a neonatal mouse assay and a mouse intestinal cell culture. Methods and Results: After artificial infection with a variety of Aeromonas spp., mRNA extracts from the two models were processed and hydridized to murine microarrays to determine host gene response. Definition of virulence was determined based on host mRNA production in murine neonatal intestinal tissue and mortality of infected animals. Infections of mouse intestinal cell cultures were then performed to determine whether this simpler model system’s mRNA responses correlated to neonatal results and therefore be predictive of virulence of Aeromonas spp. Virulent aeromonads up-regulated transcripts in both models including multiple host defense gene products (chemokines, regulation of transcription and apoptosis and cell signalling). Avirulent species exhibited little or no host response in neonates. Mortality results correlated well with both bacterial dose and average fold change of up-regulated transcripts in the neonatal mice. Conclusions: Cell culture results were less discriminating but showed promise as potentially being able to be predictive of virulence. Jun oncogene up-regulation in murine cell culture is potentially predictive of Aeromonas virulence. Significance and Impact of the Study: Having the ability to determine virulence of waterborne pathogens quickly would potentially assist public health officials to rapidly assess exposure risks.

Concentração inibitória mínima de oxitetraciclina para isolados de Aeromonas Hydrophila obtidos de diferentes fontes Minimal inhibitory concentration to oxitetracycline in Aeromonas Hydrophila strains isolated from different sources

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Delton José Pereira Júnior

2006-12-01

Full Text Available Objetivou-se com este trabalho determinar a concentração inibitória mínima (MIC de oxitetraciclina para isolados de Aeromonas hydrophila obtidos de pescado, água de cultivo de peixes e casos de septicemia hemorrágica em peixes. Foi determinado MIC de 100 isolados de A. hydrophila, oriundos de 12 pisciculturas localizadas nos Estados de Minas Gerais, Rio de Janeiro e Rio Grande do Sul, utilizando a técnica de macrodiluição em caldo. Os resultados demonstraram que 14 isolados apresentaram MIC>100 µg/mL (resistentes e 86 apresentaram MICThe aim of this paper was to determine the minimal inhibitory concentration (MIC to oxitetracycline in Aeromonas hydrophila strains isolated from marketed fish, pond water of piscicultures and fish suffering hemorrhagic septicemia. These strains were obtained from 12 different piscicultures from Minas Gerais, Rio de Janeiro e Rio Grande do Sul states. It was determined the MIC to 100 strains, using the broth macrodilution method, and the results showed that 86 strains shown value of MIC100µg/mL (classified as resistant. No differences were observed among strains isolated from marketed fish, pond water and disease outbreaks. I was concluded that the variation detected may represent a risk of selection of resistant bacterial strains in aquatic environments under use of oxitetracycline.

Effects of different replicons in conjugative plasmids on transformation efficiency, plasmid stability, gene expression and n-butanol biosynthesis in Clostridium tyrobutyricum

Energy Technology Data Exchange (ETDEWEB)

Yu, Mingrui; Du, Yinming; Jiang, Wenyan; Chang, Wei-Lun; Yang, Shang-Tian [Ohio State Univ., Columbus, OH (United States). William G. Lowrie Dept. of Chemical and Biomolecular Engineering; Tang, I-Ching [Bioprocessing Innovative Company, Dublin, OH (United States)

2012-01-15

Clostridium tyrobutyricum ATCC 25755 can produce butyric acid, acetic acid, and hydrogen as the main products from various carbon sources. In this study, C. tyrobutyricum was used as a host to produce n-butanol by expressing adhE2 gene under the control of a native thiolase promoter using four different conjugative plasmids (pMTL82151, 83151, 84151, and 85151) each with a different replicon (pBP1 from C. botulinum NCTC2916, pCB102 from C. butyricum, pCD6 from Clostridium difficile, and pIM13 from Bacillus subtilis). The effects of different replicons on transformation efficiency, plasmid stability, adhE2 expression and aldehyde/alcohol dehydrogenase activities, and butanol production by different mutants of C. tyrobutyricum were investigated. Among the four plasmids and replicons studied, pMTL82151 with pBP1 gave the highest transformation efficiency, plasmid stability, gene expression, and butanol biosynthesis. Butanol production from various substrates, including glucose, xylose, mannose, and mannitol were then investigated with the best mutant strain harboring adhE2 in pMTL82151. A high butanol titer of 20.5 g/L with 0.33 g/g yield and 0.32 g/L h productivity was obtained with mannitol as the substrate in batch fermentation with pH controlled at {proportional_to}6.0. (orig.)

Decolorisation of Congo Red by Aeromonas hydrophila Under Microaerophilic Conditions

International Nuclear Information System (INIS)

El Gizawy, S.; Refae, R.A.; Abd El Kareem, H.; Gomaa, O.M.; Hamed, H.

2009-01-01

Among 22 local bacterial isolates, Aeromonas hydrophila isolated from Bolti fish showed a remarkable ability to decolorize congo red under microaerophilic conditions (98.8% in 48 hrs) without prior adaptation. The bacterium had the ability to grow and decolorized high concentrations of congo red which varied from 50 to 1000 mg/l , the decolorisation was irrelevant to bacterial growth. The strain was capable of decolorizing congo red under a wide range of temperatures (20-40 degree C), ph (3-8), NaCl (0-200 mg/l) and also had the ability to decolorized mono, di and poly azo dyes. This bacterium is notable in its ability to decolorized the diazo congo red under extreme conditions of temperature, ph, salinity and high dye concentrations which makes it suitable for decolorisation under extreme industrial conditions

Expression, purification, crystallization and preliminary X-ray analysis of Aeromonas hydrophilia metallo-[beta]-lactamase

Energy Technology Data Exchange (ETDEWEB)

Sharma, N.; Toney, J.H.; Fitzgerald, P.M.D. (Merck)

2010-07-20

The CphA metallo-{beta}-lactamase from Aeromonas hydrophilia has been expressed, purified and crystallized by the hanging-drop vapor-diffusion method using ammonium sulfate as the precipitant. The crystals exhibit orthorhombic symmetry (P2{sub 1}2{sub 1}2), with unit-cell parameters a = 40.75, b = 42.05, c = 128.88 {angstrom}. There is one monomer in the asymmetric unit and the solvent content is estimated to be 44% by volume. A data set extending to 1.8 {angstrom} has been measured.

Genome Sequence of the Melanin-Producing Extremophile Aeromonas salmonicida subsp. pectinolytica Strain 34melT

OpenAIRE

Pavan, María Elisa; Pavan, Esteban E.; López, Nancy Irene; Levin, Laura Noemí; Pettinari, María Julia

2017-01-01

The genome of Aeromonas salmonicida subsp. pectinolytica strain 34melT, isolated from a heavily polluted river, contains several genomic islands and putative virulence genes. The identification of genes involved in resistance to different kinds of stress sheds light on the mechanisms used by this strain to thrive in an extreme environment. Fil: Pavan, María Elisa. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Departamento de Química Biológica; Argentina Fil: Pav...

Insights into dynamics of mobile genetic elements in hyperthermophilic environments from five new Thermococcus plasmids.

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Mart Krupovic

Full Text Available Mobilome of hyperthermophilic archaea dwelling in deep-sea hydrothermal vents is poorly characterized. To gain insight into genetic diversity and dynamics of mobile genetic elements in these environments we have sequenced five new plasmids from different Thermococcus strains that have been isolated from geographically remote hydrothermal vents. The plasmids were ascribed to two subfamilies, pTN2-like and pEXT9a-like. Gene content and phylogenetic analyses illuminated a robust connection between pTN2-like plasmids and Pyrococcus abyssi virus 1 (PAV1, with roughly half of the viral genome being composed of genes that have homologues in plasmids. Unexpectedly, pEXT9a-like plasmids were found to be closely related to the previously sequenced plasmid pMETVU01 from Methanocaldococcus vulcanius M7. Our data suggests that the latter observation is most compatible with an unprecedented horizontal transfer of a pEXT9a-like plasmid from Thermococcales to Methanococcales. Gene content analysis revealed that thermococcal plasmids encode Hfq-like proteins and toxin-antitoxin (TA systems of two different families, VapBC and RelBE. Notably, although abundant in archaeal genomes, to our knowledge, TA and hfq-like genes have not been previously found in archaeal plasmids or viruses. Finally, the plasmids described here might prove to be useful in developing new genetic tools for hyperthermophiles.

Two novel conjugative plasmids from a single strain of Sulfolobus

NARCIS (Netherlands)

Erauso, G.; Stedman, K.M.; Werken, van de H.J.G.; Zillig, W.; Oost, van der J.

2006-01-01

Two conjugative plasmids (CPs) were isolated and characterized from the same 'Sulfolobus islandicus' strain, SOG2/4, The plasmids were separated from each other and transferred into Sulfolobus soltataricus. One has a high copy number and is not stable (pSOG1) whereas the other has a low copy number

Bacteremia due to Aeromonas hydrophila in Acute Lymphoblastic Leukemia

International Nuclear Information System (INIS)

Fatima, A.; Afridi, F.I.; Farooqi, B.J.; Qureshi, A.; Hussain, A.

2013-01-01

Aeromonas hydrophila (A. hydrophila) is a low virulent organism but may cause devastating fatal infections in immunocompromised host especially in liver cirrhosis. It is rarely reported to cause septicemia in a patient with Acute Lymphoblastic Leukemia (ALL). The mortality rate of septicemia due to A. hydrophila is 29% to 73%. We report a case of 59-year-old female patient who was a known case of ALL, presented with the complaints of fever, lethargy and generalized weakness for one month. After taking blood samples for investigations, empirical antimicrobial therapy was started. She did not improve after 48 hours of therapy. Meanwhile blood culture revealed pure growth of A. hydrophila. After sensitivity report was available, ciprofloxacin was started. Patient became afebrile after 48 hours of treatment with ciprofloxacin. It is very vital to correctly identified and treat bacteremia due to A. hydrophila especially in the underlying leukemic patient. (author)

PEMBERIAN PROBIOTIK LACTOBACILLUS BREVIS DAN PREBIOTIK OLIGOSAKARIDA PADA BENIH PATIN SIAM (Pangasionodon hypophthalmus YANG DIINFEKSI Aeromonas hydrophila

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Yuke Eliyani

2013-08-01

Lactobacillus brevis, prebiotik oligosakarida dan sinbiotiknya terhadap jumlah bakteri Lactobacillus sp. dan total bakteri dalam usus, total eritrosit, total leukosit, diferensial leukosit, aktivitas fagositik, sintasan, tingkat pertumbuhan, serta FCR benih ikan patin siam yang diinfeksi Aeromonas hydrophila. Hasil uji karakteristik menunjukkan bahwa jenis probiotik dan patogen adalah Lactobacillus sp. dan Aeromonas hydrophila. Pada uji in vivo digunakan lima perlakuan yang terdiri atas K(+, K(-, probiotik (pro, prebiotik (pre serta sinbiotik (sin. Bakteri Lactobacillus sp. ditemukan di usus pada perlakuan probiotik dan sinbiotik dengan kisaran jumlah sekitar 101 sampai 106 (CFU/g. Total eritrosit, total leukosit, aktivitas fagositik berbeda nyata (P<0,05 dengan kontrol pada beberapa waktu pengamatan. Tingkat sintasan terendah diperoleh pada perlakuan K(+ sebesar 43,33±11,55; sedangkan empat perlakuan lainnya memperoleh nilai 100%. Tingkat pertumbuhan harian berbeda nyata antar perlakuan, nilai terbaik dicapai pada perlakuan pemberian sinbiotik sebesar 3,370±0,14. Nilai FCR perlakuan probiotik, prebiotik dan sinbiotik menunjukkan beda nyata dengan kontrol. Perlakuan sin, pre, pro memberikan nilai yang lebih baik pada total eritrosit, total leukosit, aktivitas fagositik, sintasan, pertumbuhan, dan FCR dibandingkan kontrol.

Mitochondrial pAL2-1 plasmid homologs are senescence factors in Podospora anserina independent of intrinsic senescence

NARCIS (Netherlands)

Diepeningen, van A.D.; Debets, A.J.M.; Slakhorst-Wandel, S.M.; Hoekstra, R.F.

2008-01-01

Since the first description of a linear mitochondrial plasmid in Podospora anserina, pAL2-1, and homologous plasmids have gone from being considered beneficial longevity plasmids, via neutral genetic elements, toward mutator plasmids causing senescence. The plasmid has an invertron structure, with

Mitochondrial pAL2-1 plasmid homologs are senescence factors in Podospora anserina independent of intrinsic senescence

NARCIS (Netherlands)

van Diepeningen, Anne D; Debets, Alfons J M; Slakhorst, S Marijke; Hoekstra, Rolf F

Since the first description of a linear mitochondrial plasmid in Podospora anserina, pAL2-1, and homologous plasmids have gone from being considered beneficial longevity plasmids, via neutral genetic elements, toward mutator plasmids causing senescence. The plasmid has an invertron structure, with

Insight into the mobilome of Aeromonas strains

OpenAIRE

Piotrowska, Marta; Popowska, Magdalena

2015-01-01

The mobilome is a pool of genes located within mobile genetic elements (MGE), such as plasmids, IS elements, transposons, genomic/pathogenicity islands, and integron-associated gene cassettes. These genes are often referred to as ?flexible? and may encode virulence factors, toxic compounds as well as resistance to antibiotics. The phenomenon of MGE transfer between bacteria, known as horizontal gene transfer (HGT), is well documented. The genes present on MGE are subject to continuous process...

Development of highly sensitive electrochemical genosensor based on multiwalled carbon nanotubes-chitosan-bismuth and lead sulfide nanoparticles for the detection of pathogenic Aeromonas.

Science.gov (United States)

Fernandes, António Maximiano; Abdalhai, Mandour H; Ji, Jian; Xi, Bing-Wen; Xie, Jun; Sun, Jiadi; Noeline, Rasoamandrary; Lee, Byong H; Sun, Xiulan

2015-01-15

In this paper, we reported the construction of new high sensitive electrochemical genosensor based on multiwalled carbon nanotubes-chitosan-bismuth complex (MWCNT-Chi-Bi) and lead sulfide nanoparticles for the detection of pathogenic Aeromonas. Lead sulfide nanoparticles capped with 5'-(NH2) oligonucleotides thought amide bond was used as signalizing probe DNA (sz-DNA) and thiol-modified oligonucleotides sequence was used as fixing probe DNA (fDNA). The two probes hybridize with target Aeromonas DNA (tDNA) sequence (fDNA-tDNA-szDNA). The signal of hybridization is detected by differential pulse voltammetry (DPV) after electrodeposition of released lead nanoparticles (PbS) from sz-DNA on the surface of glass carbon electrode decorated with MWCNT-Chi-Bi, which improves the deposition and traducing electrical signal. The optimization of incubation time, hybridization temperature, deposition potential, deposition time and the specificity of the probes were investigated. Our results showed the highest sensibility to detect the target gene when compared with related biosensors and polymerase chain reaction (PCR). The detection limit for this biosensor was 1.0×10(-14) M. We could detect lower than 10(2) CFU mL(-1) of Aeromonas in spiked tap water. This method is rapid and sensitive for the detection of pathogenic bacteria and would become a potential application in biomedical diagnosis, food safety and environmental monitoring. Copyright © 2014 Elsevier B.V. All rights reserved.

Plasmid profiles and antibiotic susceptibility patterns of Staphylococcus aureus isolates from Nigeria.

Science.gov (United States)

Olukoya, D K; Asielue, J O; Olasupo, N A; Ikea, J K

1995-06-01

In an investigation into the problems of infections due to Staphylococcus aureus in Nigeria, 100 strains were isolated from various hospitals in Lagos. The strains were screened for the presence of plasmids and for susceptibility to antimicrobial agents. Plasmids were extracted by modification of the method of Takahashi and Nagono[1]. The plasmids were diverse in nature. The strains were found to be highly resistant to commonly prescribed antibiotics.

Computational design and characterization of a temperature-sensitive plasmid replicon for gram positive thermophiles

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Olson Daniel G

2012-05-01

Full Text Available Abstract Background Temperature-sensitive (Ts plasmids are useful tools for genetic engineering, but there are currently none compatible with the gram positive, thermophilic, obligate anaerobe, Clostridium thermocellum. Traditional mutagenesis techniques yield Ts mutants at a low frequency, and therefore requires the development of high-throughput screening protocols, which are also not available for this organism. Recently there has been progress in the development of computer algorithms which can predict Ts mutations. Most plasmids currently used for genetic modification of C. thermocellum are based on the replicon of plasmid pNW33N, which replicates using the RepB replication protein. To address this problem, we set out to create a Ts plasmid by mutating the gene coding for the RepB replication protein using an algorithm designed by Varadarajan et al. (1996 for predicting Ts mutants based on the amino-acid sequence of the protein. Results A library of 34 mutant plasmids was designed, synthesized and screened, resulting in 6 mutants which exhibited a Ts phenotype. Of these 6, the one with the most temperature-sensitive phenotype (M166A was compared with the original plasmid. It exhibited lower stability at 48°C and was completely unable to replicate at 55°C. Conclusions The plasmid described in this work could be useful in future efforts to genetically engineer C. thermocellum, and the method used to generate this plasmid may be useful for others trying to make Ts plasmids.

Giant linear plasmids in Streptomyces: a treasure trove of antibiotic biosynthetic clusters.

Science.gov (United States)

Kinashi, Haruyasu

2011-01-01

Many giant linear plasmids have been isolated from Streptomyces by using pulsed-field gel electrophoresis and some of them were found to carry an antibiotic biosynthetic cluster(s); SCP1 carries biosynthetic genes for methylenomycin, pSLA2-L for lankacidin and lankamycin, and pKSL for lasalocid and echinomycin. Accumulated data suggest that giant linear plasmids have played critical roles in genome evolution and horizontal transfer of secondary metabolism. In this review, I summarize typical examples of giant linear plasmids whose involvement in antibiotic production has been studied in some detail, emphasizing their finding processes and interaction with the host chromosomes. A hypothesis on horizontal transfer of secondary metabolism involving giant linear plasmids is proposed at the end.

Using the CRISPR/Cas9 system to eliminate native plasmids of Zymomonas mobilis ZM4.

Science.gov (United States)

Cao, Qing-Hua; Shao, Huan-Huan; Qiu, Hui; Li, Tao; Zhang, Yi-Zheng; Tan, Xue-Mei

2017-03-01

The CRISPR/Cas system can be used to simply and efficiently edit the genomes of various species, including animals, plants, and microbes. Zymomonas mobilis ZM4 is a highly efficient, ethanol-producing bacterium that contains five native plasmids. Here, we constructed the pSUZM2a-Cas9 plasmid and a single-guide RNA expression plasmid. The pSUZM2a-Cas9 plasmid was used to express the Cas9 gene cloned from Streptococcus pyogenes CICC 10464. The single-guide RNA expression plasmid pUC-T7sgRNA, with a T7 promoter, can be used for the in vitro synthesis of single-guide RNAs. This system was successfully employed to knockout the upp gene of Escherichia coli and the replicase genes of native Z. mobilis plasmids. This is the first study to apply the CRISPR/Cas9 system of S. pyogenes to eliminate native plasmids in Z. mobilis. It provides a new method for plasmid curing and paves the way for the genomic engineering of Z. mobilis.

Transfer of conjugative plasmids among bacteria under environmentally relevant conditions

DEFF Research Database (Denmark)

Musovic, Sanin

Mobile genetiske elementer (f.eks. plasmider), der ofte bærer ekstra funktioner såsom antibiotikaresistens, eller kataboliske- og xenobiotiske nedbrydnings gener, antages at have en meget vigtigt evolutionær rolle for bakterier. I denne PhD afhandling undersøgte jeg størrelsen af plasmid overførs...

Characterization of Endogenous Plasmids from Lactobacillus salivarius UCC118▿ †

OpenAIRE

Fang, Fang; Flynn, Sarah; Li, Yin; Claesson, Marcus J.; van Pijkeren, Jan-Peter; Collins, J. Kevin; van Sinderen, Douwe; O'Toole, Paul W.

2008-01-01

The genome of Lactobacillus salivarius UCC118 comprises a 1.83-Mb chromosome, a 242-kb megaplasmid (pMP118), and two smaller plasmids of 20 kb (pSF118-20) and 44 kb (pSF118-44). Annotation and bioinformatic analyses suggest that both of the smaller plasmids replicate by a theta replication mechanism. Furthermore, it appears that they are transmissible, although neither possesses a complete set of conjugation genes. Plasmid pSF118-20 encodes a toxin-antitoxin system composed of pemI and pemK h...

Vaccination in Nile tilapia broodstock with whole cell vaccine and disease resistance in its fry against Aeromonas hydrophila

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Sukenda Sukenda

2017-07-01

Full Text Available ABSTRACT The aim of this study was to analyze the effectivity of vaccination in Nile tilapia broodstock with whole cell vaccine and disease resistance in fry tilapia against Aeromonas hydrophila. Tilapia Nirwana strain that used for this had average body weight of 185±13.23 g and were maintained in ponds sizing of (2.5×2.5×1 m3. Vaccinations that has been done through intraperitoneal injection using dose of 0.1 mL/fish, meanwhile the fish for control was injected by phosphate buffered saline (PBS. This study used complete randomized design with two treatments and three replications. Antibody level was measured by using indirect enzyme-linked immunosorbent assay (ELISA method in the broodstock, egg, and fry.  Challenge test in fry tilapia performed at the age of 5, 10, and 15 days. The results showed that vaccination in tilapia broodstock delivered a significant antibody level in broodstock, eggs, and fry (P<0.05 compared to the control. Relative percent survival of offspring at 5, 10, and 15 days were 78.26%, 70.59%, and 65.52%, respectively.  As a conclusion, vaccination in tilapia broodstock was effective to improve specific and non-specific immunity, and protect fry tilapia from A. hydrophila infection through maternal immunity. Keywords: vaccination, antibody, maternal immunity, tilapia, Aeromonas hydrophila  ABSTRAK Penelitian ini bertujuan untuk menganalisis efikasi vaksinasi pada induk nila dengan vaksin sel utuh dan ketahanan benih yang dihasilkan terhadap Aeromonas hydrophila. Ikan nila stain Nirwana yang digunakan dalam penelitian memiliki bobot rata-rata 185±13,23 g dan ikan dipelihara dalam kolam (2,5×2,5×1 m3. vaksinasi dilakukan melalui penyuntikan intraperitoneal dengan dosis 0,1 mL/ikan, sementara itu ikan kontrol disuntik dengan phosphate buffered saline (PBS. Penelitian ini menggunakan rancangan acak lengkap dengan dua perlakuan dan tiga ulangan. Tingkat antibodi diukur dengan menggunakan metode indirect enzyme

Isolation and properties of plasmids from Deinococcus radiodurans Sark

International Nuclear Information System (INIS)

Sjarief, S.H.; Kikuchi, Masahiro; Kurita, Hiromi; Kitayama, Shigeru; Watanabe, Hiroshi.

1990-05-01

Radioresistant bacterium, Deinococcus radiodurans, can repair completely almost all of DNA damages including double strand breaks induced by gamma-rays up to about 5 kGy. In order to reveal the repair mechanism, it is necessary to develop a cloning vector available for the genetic analysis. We tried to isolate plasmids from D.radiodurans Sark strain. In the present paper the isolation and properties of plasmids were described. (author)

PEMBERIAN TOTAL FENOL TERIPANG PASIR (Holothuria scabra UNTUK MENINGKATKAN LEUKOSIT DAN DIFERENSIAL LEUKOSIT IKAN MAS (Cyprinus carpio YANG DIINFEKSI BAKTERI Aeromonas Hydrophila

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Achmad Suhermanto

2011-10-01

Full Text Available Freshwater fishery commodities are most likely to be increased production of carp (Cyprinus carpio. Intensification of cultivation which raises new problems with fish disease outbreaks caused by Aeromonas hydrophila. Providing of immunostimulatory bioactive compounds of sea cucumbers (Holothuria scabra can enhance non-specific immune responses in the goldfish as a mechanism of defense against disease. The purpose of this study is to determine the role and optimal dose of total phenols sea cucumber in enhancing non-specific immune response seen from the hematology parameters Extraction of bioactive components from sea cucumber prepared by using methanol and fractionated with ethyl acetate solvent (v/v. Identification of total phenols in ethyl acetate fraction performed using UV-Vis spectrophotometer and infrared. Total phenol produced was tested on carp with intraperitonial injection, the concentration of 0.09, 0.18 and 0.27 mg phenol/kg fish. Challenge test was done by using the Aeromonas hydrophila (107 cells/ml through the immersion method. The observations included hematological parameters and total plasma proteins.The observations of hematological parameters that Leukocytes, Neutrophils pre-and post-infection were significantly increased. Lymphocyte pre infection was increased significantly and post-bacterial infection was decreased significantly. Eosinophils, Monocytes pre-and post-bacterial infection were not differ significantly between treatment. The use of phenolic compounds at 0.09 mg / kg can be increase of non-specific immune response in carp (Cyprinus carpio. Key Words : Total phenol, Aeromonas hydrophila, Cyprinus carpio, nonspecific immune response 

Prevalence of listeria, Aeromonas, and Vibrio species in fish used for human consumption in Turkey.

Science.gov (United States)

Yücel, Nihal; Balci, Senay

2010-02-01

A total of 78 raw retail fish samples from 30 freshwater and 48 marine fish were examined for the presence of Listeria, Aeromonas, and Vibrio species. The overall incidence of Listeria spp. was 30% in freshwater samples and 10.4% in marine fish samples. Listeria monocytogenes (44.5%) was the most commonly isolated species in freshwater fish, and Listeria murrayi (83.5%) was the most commonly isolated species in marine fish samples. Motile aeromonads were more common in marine fish samples (93.7%) than in freshwater fish samples (10%). Vibrio alginolyticus, Vibrio fluvialis, and Vibrio damsela were isolated only in marine fish samples, representing 40.9, 38.6, and 36.3% of Vibrio isolates, respectively. In freshwater and marine fish, the highest incidences of Listeria and Aeromonas were found in skin samples; the highest incidence of Vibrio in marine fish was found in gill samples. The location of Listeria spp. and L. monocytogenes in a fish was significantly different among freshwater fish. A high incidence of these bacterial pathogens was found in the brown trout (Salmo trutta) and horse mackerel (Trachurus trachurus). Handling of contaminated fish, cross-contamination, or eating raw fish might pose a health hazard, especially in immunosuppressed individuals, elderly people, and children. This study highlights the importance of bacterial pathogens in fish intended for human consumption, but more study is needed.

Molecular processes as basis for plasmid-mediated bacterial UV-light resistance and mutagenesis

International Nuclear Information System (INIS)

Aleshkin, G.I.; Brukhanskij, G.V.; Skavronskaya, A.G.

1985-01-01

The increase of UV-resistance and UV-induced mutagenesis by lambda 1 pint intmid as well as molecular-genetic mechanisms of plasmid participation in reparation and DNA replication and its degradation after UV-irradiation in plasmid cells on pKM101 plasmid model have been investigated. Data testifying to the necessity of intmid integration in chromosome as obligatory stage of intmid participation in increasing UV-resistance of bacterial cells are obtained. It has been found that intmid raises UV-resistance of cells and increases respectively the UV-induced reverants efficiency. On the basis of the experiment data the conclusion is drawn that the intmid capacity to raise UV-resistance and, possibly, mutagenesis is bound not only with its integration into chromosome but also with pol A + chromosome replication by dependendent imtmid replication complex. It is shown that pKM101 plasmid ensures functioning in E coli cells of inducible, chloroamphenicol-resistant DNA replication, highly resistant to UV-light harmful effect and that the volume of excision reparation in E. coli cells carrying pKM101 plasmid is increased as compared with the volume of reparation in plasmid legs cells. The combination of the data obtained gives grounds to the authors to assume that inducible replication, inducible reparation of DNA and inducible decrease of DNA degradation determined by pKM101 plasmid may serve as recA + lexA + basis dependent increase of UV-resistance and mutagenesis and that these processes provide the possibility of functioning of integrative replication mechanism of plasmid participation in ensuring UV-resistance and mutagenesis of plants

Analysis of plasmid profiling as a method for rapid differentiation of food-associated Clostridium perfringens strains.

Science.gov (United States)

Jones, M K; Iwanejko, L A; Longden, M S

1989-09-01

Plasmid analysis of over 120 strains of Clostridium perfringens, isolated during food-poisoning incidents and from animal carcasses and food constituents with no association with food poisoning, showed the potential of plasmid profiling as a means of differentiating epidemiologically related strains. On average 65% of freshly isolated strains contained one or more plasmids which could be used in the analysis. Comparison of profiles of strains from unrelated sources or unrelated strains from the same source showed a particularly wide variety of plasmid profiles. Thus the possibility that epidemiologically-unrelated strains might possess similar profiles appears to be very low in this organism. Analysis of serologically-related strains from the same source revealed similar plasmid profiles in all the plasmid-bearing strains examined. A high proportion (71%) of fresh and well-characterized food-poisoning strains possessed plasmids of 6.2 kb in size (compared with 19% of non-food-poisoning strains). The possible role of these plasmids is discussed, since the structural gene encoding the enterotoxin type A was not present on any of the plasmids in the food-poisoning strains tested.

Presence of Glycopeptide-Encoding Plasmids in Enterococcal Isolates from Food and Humans in Denmark

DEFF Research Database (Denmark)

Migura, Lourdes Garcia; Valenzuela, Antonio Jesus Sanchez; Jensen, Lars Bogø

2011-01-01

developed techniques for classification of plasmids. Replicons associated with sex pheromone-inducible plasmids were detected in all GR E. faecalis, whereas GR Enterococcus faecium contained plasmids known to be widely distributed among enterococci. vanA resistance is common in E. faecium isolates from meat...... and animals in Europe and is rarely found in E. faecalis. This article describes the first characterization of MGE from vanA mediated E. faecalis, thus linking this resistance genotype to pheromone responding plasmids....

Infectious alphavirus production from a simple plasmid transfection+

Directory of Open Access Journals (Sweden)

Olson Ken E

2011-07-01

Full Text Available Abstract We have developed a new method for producing infectious double subgenomic alphaviruses from plasmids transfected into mammalian cells. A double subgenomic Sindbis virus (TE3'2J was transcribed from a cytomegalovirus PolII promoter, which results in the production of infectious virus. Transfection of as little as 125 ng of plasmid is able to produce 1 × 108 plaque forming units/ml (PFU/ml of infectious virus 48 hours post-transfection. This system represents a more efficient method for producing recombinant Sindbis viruses.

Pancarditis in a patient with tropical pyomyositis due to Aeromonas infection

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Nikhil Gupta

2015-01-01

Full Text Available Tropical pyomyositis is a suppurative disease of the skeletal muscles. The most common site of the infection being muscles of the thigh. Staphylococcus aureus is the most common organism isolated. Aeromonas is one of the rarest organisms described as the etiologic agent for this disease. Rarely, cardiac involvement in pyomyositis has been described in the form of myocarditis and pyopericardium. Pancarditis is a very rare event in the natural course of pyomyositis. To the best of our knowledge, there is a single case report in world literature regarding involvement of all the layers of the heart in pyomyositis. We report a case of a 30-year-old immunocompetent male who had pyomyositis and developed pancarditis, which was managed successfully with conservative management.

Conjugal plasmid transfer (pAM beta 1) in Lactobacillus plantarum.

OpenAIRE

Shrago, A W; Chassy, B M; Dobrogosz, W J

1986-01-01

The streptococcal plasmid pAM beta 1 (erythromycin resistance) was transferred via conjugation from Streptococcus faecalis to Lactobacillus plantarum and was transferred among L. plantarum strains. Streptococcus sanguis Challis was transformed with pAM beta 1 isolated from these transconjugants, and transformants harboring intact pAM beta 1 could conjugate the plasmid back to L. plantarum.

Plasmid profiling of bacterial isolates from confined environments

Science.gov (United States)

van Houdt, Rob; Provoost, Ann; Coninx, Ilse; Leys, Natalie; Mergeay, Max

Plasmid profiling of bacterial isolates from confined environments R. Van Houdt, I. Coninx, A. Provoost, N. Leys, and M. Mergeay Expertise group for Molecular and Cellular Biology, Institute for Environment, Health and Safety, Belgian Nuclear Research Centre (SCK•CEN), Boeretang 200, B-2400 Mol, Belgium. Human exploration of extreme and isolated hostile environments such as space requires special confined small volume habitats to protect and house the crew. However, human confinement in such small volume habitats has restrictions on waste disposal and personal hygiene and inevitably generates a particular community of microorganisms within the habitat. These microorganisms are mainly originating from the crew (skin, mucous membranes, upper respiratory tract, mouth, and gastrointestinal tract) but also include the residing environmental microorganisms. Earth-based confined habitats such as the Antarctic Research Station Concordia are used as test beds for long-duration spaceflights to study the physiologic and psychological adaptation to isolated environments. The dynamics of the environmental microbial population in such a test bed could render additional insights in assessing the potential health risks in long-duration space missions. Not only total bacterial contamination levels are important, but it is essential to identify also the predominant microbial taxa and their mobile genetic elements (MGE). These MGEs could be exchanged between bacteria by horizontal gene transfer and may alter the pathogenic potential since they often carry antibiotic resistance or more in general adaptation-enhancing traits. In this study several bacterial strains isolated in the Concordia research station were examined for their plasmid content. An optimized protocol for extraction of large plasmids showed the present of at least one plasmid in 50% of the strains. For all strains the minimal inhibitory concentration of a range of antibiotics was determined indicating resistance to

Survival and evolution of a large multidrug resistance plasmid in new clinical bacterial hosts

DEFF Research Database (Denmark)

Porse, Andreas; Schønning, Kristian; Munck, Christian

2016-01-01

sequencing to show that the long-term persistence and molecular integrity of the plasmid is highly influenced by multiple factors within a 25 kb plasmid region constituting a host-dependent burden. In the E. coli hosts investigated here, improved plasmid stability readily evolves via IS26 mediated deletions...... consistently followed by all evolved E. coli lineages exposes a trade-off between horizontal and vertical transmission that may ultimately limit the dissemination potential of clinical multidrug resistance plasmids in these hosts....

Repair of UV-irradiated plasmid DNA in excision repair deficient mutants of Saccharomyces cerevisiae

International Nuclear Information System (INIS)

Ikai, K.; Tano, K.; Ohnishi, T.; Nozu, K.

1985-01-01

The repair of UV-irradiated DNA of plasmid YEp13 was studied in the incision defective strains by measurement of cell transformation frequency. In Saccharomyces cerevisiae, rad1,2,3 and 4 mutants could repair UV-damaged plasmid DNA. In Escherichia coli, uvrA mutant was unable to repair UV-damaged plasmid DNA; however, pretreatment of the plasmid with Micrococcus luteus endonuclease increased repair. It was concluded that all the mutations of yeast were probably limited only to the nuclear DNA. (author)

Hematologia e sinais clínicos de Piaractus mesopotamicus infectados experimentalmente com Aeromonas hydrophila = Hematology and clinical signs of Piaractus mesopotamicus experimentally infected with Aeromonas hydrophila

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Flávio Ruas Moraes

2009-01-01

Full Text Available Este ensaio teve como objetivo avaliar as respostas hematológicas e a ocorrência de sinais clínico-patológicos de Piaractus mesopotamicus infectados experimentalmente por Aeromonas hydrophila. Foram utilizados 324 pacus, P. mesopotamicus, com peso de 102,84 ±27,1 g, distribuídos em 27 caixas de 300 L de capacidade, sendo 14 peixes por caixa. Os peixes foram mantidos nas caixas durante um mês, recebendo dieta balanceada, período em que se evitou qualquer tipo de manejo estressante. Passado esse período, foram infectadoscom 6 x 106 UFC de A. hydrophila, injetada via intraperitoneal. As coletas e análises de sangue foram realizadas 24h antes da infecção experimental e 24h após a infecção. Os resultados permitem concluir que a infecção por A. hydrophila em P. mesopotamicus écaracterizada por escurecimento da derme e sinais clínicos-patológicos relacionados à hemorragia, anemia normocítica-hipocrômica, redução nos níveis de proteínas, globulinasplasmáticas e eosinófilos, leucopenia, linfopenia, trombocitopenia, neutrofilia e monocitose. The purpose of this study was to evaluate the hematological response and clinical sign of Piaractus mesopotamicus infected byAeromonas hydrophila. Were used 324 pacus, P. mesopotamicus weighing 102.84 ± 27.1 g distributed in 27 water tanks with 300 L of capacity, 14 fish per tank. The fish were kept in the water tanks during one month, receiving appropriate diet. In this period was avoidedstressing management. After this period, the fish were infected with 6 × 108 cfu of A. hydrophila fish-1, injected intraperitoneally. The blood collection was carried 24h before experimental infection and 24h after its. The A. hydrophila infection in P. mesopotamicus ischaracterized by dark skin and clinical signs related to hemorrhage, hypochromic normocytic anemia, decrease on plasmatic proteins and globulins levels, leucopenia, lymphopenia, thrombocytopenia, eosinophilia, neutrophilia and monocytosis.

Plasmid DNA Analysis of Pasteurella multocida Serotype B isolated from Haemorrhagic Septicaemia outbreaks in Malaysia

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Jamal, H.

2005-01-01

Full Text Available A total of 150 purified isolates of Pasteurella multocida serotype B were used (Salmah, 2004 for plasmid DNA curing experiment to determine hyaluronidase activity, antibiotic resistance pattern (ARP and mice lethality test (LD50 for their role of pathogenicity. A plasmid curing experiment was carried out by using the intercalating agent; ethidium bromide and rifampicin, where it was found all the plasmids had been cured (plasmidless from Pasteurella multocida. All of these plasmidless isolates maintained their phenotypic characteristics. They showed the same antibiotic resistancepattern as before curing, produced hyaluronidase and possessed lethality activity in mice when injected intraperitoneally(i.p. Based on this observation, the antibiotic resistance, hyaluronidase activity and mice virulence could probably be chromosomal-mediated. Plasmids were detected 100% in all P. multocida isolates with identical profile of 2 plasmids size 3.0 and 5.5 kb. No large plasmids could be detected in all isolates. Since all the isolates appeared to have identicalplasmid profiles, they were subjected to restriction enzyme(RE analysis. From RE analysis results obtained, it can be concluded that the plasmid DNA in serotype B isolates are identical. Only 4 of 32 REs were found to cleave these plasmids with identical restriction fingerprints; BglII, HaeIII, RsaI and SspI. From RE analysis results, it can be concluded that the plasmid DNA isolates are identical. This plasmid might not played any role in pathogenicity of Pasteurella multocida serotype B, however this information is important for the construction of shuttle vectors in genetic studies of the pathogenicity of haemorrhagic septicaemia(HS.

Plasmid ColE1 as a Molecular Vehicle for Cloning and Amplification of DNA

Science.gov (United States)

Hershfield, Vickers; Boyer, Herbert W.; Yanofsky, Charles; Lovett, Michael A.; Helinski, Donald R.

1974-01-01

DNA fragments obtained from EcoRI endonuclease digestion of bacteriophage ϕ80pt190 (trp+) and the plasmid ColE1 were covalently joined with polynucleotide ligase. Transformation of Escherichia coli trp- strains to tryptophan independence with the recombined DNA selected for reconstituted ColE1 plasmids containing the tryptophan operon and the ϕ80 immunity region. Similarly, an EcoRI endonuclease generated fragment of plasmid pSC105 DNA containing the genetic determinant of kanamycin resistance was inserted into the ColE1 plasmid and recovered in E. coli. The plasmids containing the trp operon (ColE1-trp) and the kanamycin resistance gene were maintained under logarithmic growth conditions at a level of 25-30 copies per cell and accumulate to the extent of several hundred copies per cell in the presence of chloramphenicol. Cells carrying the ColE1-trp plasmid determined the production of highly elevated levels of trp operon-specific mRNA and tryptophan biosynthetic enzymes. Images PMID:4610576

Centromere pairing by a plasmid-encoded type I ParB protein

DEFF Research Database (Denmark)

Ringgaard, Simon; Löwe, Jan; Gerdes, Kenn

2007-01-01

The par2 locus of Escherichia coli plasmid pB171 encodes two trans-acting proteins, ParA and ParB, and two cis-acting sites, parC1 and parC2, to which ParB binds cooperatively. ParA is related to MinD and oscillates in helical structures and thereby positions ParB/parC-carrying plasmids regularly......, hence identifying the N terminus of ParB as a requirement for ParB-mediated centromere pairing. These observations suggest that centromere pairing is an important intermediate step in plasmid partitioning mediated by the common type I loci....

An Enterobacter plasmid as a new genetic background for the transposon Tn1331

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Alavi MR

2011-11-01

Full Text Available Mohammad R Alavi1,2, Vlado Antonic2, Adrien Ravizee1, Peter J Weina3, Mina Izadjoo1,2, Alexander Stojadinovic21Division of Wound Biology and Translational Research, Armed Forces Institute of Pathology and American Registry of Pathology, Washington DC, 2Combat Wound Initiative Program, Walter Reed Army Medical Center, Washington DC, 3The Walter Reed Army Institute of Research, Silver Spring, MD, USABackground: Genus Enterobacter includes important opportunistic nosocomial pathogens that could infect complex wounds. The presence of antibiotic resistance genes in these microorganisms represents a challenging clinical problem in the treatment of these wounds. In the authors’ screening of antibiotic-resistant bacteria from complex wounds, an Enterobacter species was isolated that harbors antibiotic-resistant plasmids conferring resistance to Escherichia coli. The aim of this study was to identify the resistance genes carried by one of these plasmids.Methods: The plasmids from the Enterobacter isolate were propagated in E. coli and one of the plasmids, designated as pR23, was sequenced by the Sanger method using fluorescent dye-terminator chemistry on a genetic analyzer. The assembled sequence was annotated by search of the GenBank database.Results: Plasmid pR23 is composed of the transposon Tn1331 and a backbone plasmid that is identical to the plasmid pPIGDM1 from Enterobacter agglomerans. The multidrug-resistance transposon Tn1331, which confers resistance to aminoglycoside and beta lactam antibiotics, has been previously isolated only from Klebsiella. The Enterobacter plasmid pPIGDM1, which carries a ColE1-like origin of replication and has no apparent selective marker, appears to provide a backbone for propagation of Tn1331 in Enterobacter. The recognition sequence of Tn1331 transposase for insertion into pPIGDM1 is the pentanucleotide TATTA, which occurs only once throughout the length of this plasmid.Conclusion: Transposition of Tn1331 into

Quorum-Dependent Mannopine-Inducible Conjugative Transfer of an Agrobacterium Opine-Catabolic Plasmid

Science.gov (United States)

Wetzel, Margaret E.; Kim, Kun-Soo; Miller, Marilyn; Olsen, Gary J.

2014-01-01

The Ti plasmid in Agrobacterium tumefaciens strain 15955 carries two alleles of traR that regulate conjugative transfer. The first is a functional allele, called traR, that is transcriptionally induced by the opine octopine. The second, trlR, is a nonfunctional, dominant-negative mutant located in an operon that is inducible by the opine mannopine (MOP). Based on these findings, we predicted that there exist wild-type agrobacterial strains harboring plasmids in which MOP induces a functional traR and, hence, conjugation. We analyzed 11 MOP-utilizing field isolates and found five where MOP induced transfer of the MOP-catabolic element and increased production of the acyl-homoserine lactone (acyl-HSL) quormone. The transmissible elements in these five strains represent a set of highly related plasmids. Sequence analysis of one such plasmid, pAoF64/95, revealed that the 176-kb element is not a Ti plasmid but carries genes for catabolism of MOP, mannopinic acid (MOA), agropinic acid (AGA), and the agrocinopines. The plasmid additionally carries all of the genes required for conjugative transfer, including the regulatory genes traR, traI, and traM. The traR gene, however, is not located in the MOP catabolism region. The gene, instead, is monocistronic and located within the tra-trb-rep gene cluster. A traR mutant failed to transfer the plasmid and produced little to no quormone even when grown with MOP, indicating that TraRpAoF64/95 is the activator of the tra regulon. A traM mutant was constitutive for transfer and acyl-HSL production, indicating that the anti-activator function of TraM is conserved. PMID:24363349

Plasmids which make their host bacteria mutable as well as resistant to ultraviolet irradiation

International Nuclear Information System (INIS)

Arai, Toshihiko; Ando, Takao

1980-01-01

Some of the naturally occurring Iα, I zeta, M, N, O and T group plasmids increase both the mutability and UV resistance of their host bacteria, while group H and S plasmids only increase mutability. This suggests that these two plasmid-mediated repair functions are separable. The two functions have no direct relation to their restriction-modification systems and nitrofuran resistant functions. In addition, the close linking between the restriction-modification genes and these repair function genes was suggested in group N plasmids. (author)

Antibiotic resistance and plasmid carriage among Escherichia coli isolates from chicken meat in Malaysia

International Nuclear Information System (INIS)

Tin Tin Myaing; Saleha, A.A.; Arifah, A.K.; Raha, A.R.

2005-01-01

Escherichia coli isolates from 131 raw chicken meat samples were tested for susceptibility to 12 antibiotics. Plasmids were isolated from many samples and their DNA molecular weight calculated. An 81.7% plasmid occurrence rate was observed among the isolates, ranging from 0 to 8 in number and with sizes from 1.2 to 118.6 MDa. Plasmids were detected in 93.8% of E. coIi isolates resistant to all 12 antibiotics, and in 90.5% of E. coli isolates resistant to 11. Three (2.8%) isolates harboured 8 plasmids and were resistant to all 12 antibiotics. Antibiotic resistant genes in bacteria are usually carried in extrachromosomal DNA and it is postulated that E. coli with a high number of plasmids possesses wider resistance to antibiotics. (author)

Expansion of a plasmid classification system for Gram-positive bacteria and determination of the diversity of plasmids in Staphylococcus aureus strains of human, animal, and food origins

DEFF Research Database (Denmark)

Lozano, C.; Garcia-Migura, L.; Aspiroz, C.

2012-01-01

An expansion of a previously described plasmid classification was performed and used to reveal the plasmid content of a collection of 92 Staphylococcus aureus strains of different origins. rep genes of other genera were detected in Staphylococcus. S1 pulsed-field gel electrophoresis (PFGE) hybrid...

Specific structural probing of plasmid-coded ribosomal RNAs from Escherichia coli

DEFF Research Database (Denmark)

Aagaard, C; Rosendahl, G; Dam, M

1991-01-01

The preferred method for construction and in vivo expression of mutagenised Escherichia coli ribosomal RNAs (rRNAs) is via high copy number plasmids. Transcription of wild-type rRNA from the seven chromosomal rrn operons in strains harbouring plasmid-coded mutant rRNAs leads to a heterogeneous...

Novel Plasmid Transformation Method Mediated by Chrysotile, Sliding Friction, and Elastic Body Exposure

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Naoto Yoshida

2007-01-01

Full Text Available Escherichia coli as a plasmid recipient cell was dispersed in a chrysotile colloidal solution, containing chrysotile adsorbed to plasmid DNA (chrysotile-plasmid cell mixture. Following this, the chrysotile-plasmid cell mixture was dropped onto the surface of an elastic body, such as agarose, and treated physically by sliding a polystyrene streak bar over the elastic body to create friction. Plasmid DNA was easily incorporated into E. coli, and antibiotic resistance was conferred by transformation. The transformation efficiency of E. coli cultured in solid medium was greater than that of E. coli cultured in broth. To obtain greater transformation efficiency, we attempted to determine optimal transformation conditions. The following conditions resulted in the greatest transformation efficiency: the recipient cell concentration within the chrysotileplasmid cell mixture had an optical density greater than or equal to 2 at 550 nm, the vertical reaction force applied to the streak bar was greater than or equal to 40 g, and the rotation speed of the elastic body was greater than or equal to 34 rpm. Under these conditions, we observed a transformation efficiency of 107 per μg plasmid DNA. The advantage of achieving bacterial transformation using the elastic body exposure method is that competent cell preparation of the recipient cell is not required. In addition to E. coli, other Gram negative bacteria are able to acquire plasmid DNA using the elastic body exposure method.

Plasmid Transfer in the Ocean – A Case Study from the Roseobacter Group

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Jörn Petersen

2017-07-01

Full Text Available Plasmid mediated horizontal gene transfer (HGT has been speculated to be one of the prime mechanisms for the adaptation of roseobacters (Rhodobacteraceae to their ecological niches in the marine habitat. Their plasmids contain ecologically crucial functional modules of up to ∼40-kb in size, e.g., for aerobic anoxygenic photosynthesis, flagellar formation and the biosynthesis of the antibiotic tropodithietic acid. Furthermore, the widely present type four secretion system (T4SS of roseobacters has been shown to mediate conjugation across genus barriers, albeit in the laboratory. Here we discovered that Confluentimicrobium naphthalenivorans NS6T, a tidal flat bacterium isolated in Korea, carries a 185-kb plasmid, which exhibits a long-range synteny with the conjugative 126-kb plasmid of Dinoroseobacter shibae DFL12T. Both replicons are stably maintained by RepABC operons of the same compatibility group (-2 and they harbor a homologous T4SS. Principal component analysis of the codon usage shows a large similarity between the two plasmids, while the chromosomes are very distinct, showing that neither of the two bacterial species represents the original host of those RepABC-2 type plasmids. The two species do not share a common habitat today and they are phylogenetically only distantly related. Our finding demonstrates the first clear-cut evidence for conjugational plasmid transfer across biogeographical and phylogenetic barriers in Rhodobacteraceae and documents the importance of conjugative HGT in the ocean.

Plasmid mediated quinolone resistance in Enterobacteriaceae

NARCIS (Netherlands)

Veldman, K.T.; LS Klinisch Onderzoek Wagenaar

2014-01-01

This thesis describes the occurrence of Plasmid Mediated Quinolone Resistance (PMQR) in Salmonella and E. coli from The Netherlands and other European countries. Furthermore, the genetic background of these genes was characterized. Fluoroquinolones are widely used antibiotics in both human and

Plasmid and chromosome segregation in prokaryotes

DEFF Research Database (Denmark)

Møller-Jensen, Jakob; Bugge Jensen, Rasmus; Gerdes, Kenn

2000-01-01

Recent major advances in the understanding of prokaryotic DNA segregation have been achieved by using fluorescence microscopy to visualize the localization of cellular components. Plasmids and bacterial chromosomes are partitioned in a highly dynamic fashion, suggesting the presence of a mitotic...

Frequent conjugative transfer accelerates adaptation of a broad-host-range plasmid to an unfavorable Pseudomonas putida host.

Science.gov (United States)

Heuer, Holger; Fox, Randal E; Top, Eva M

2007-03-01

IncP-1 plasmids are known to be promiscuous, but it is not understood if they are equally well adapted to various species within their host range. Moreover, little is known about their fate in bacterial communities. We determined if the IncP-1beta plasmid pB10 was unstable in some Proteobacteria, and whether plasmid stability was enhanced after long-term carriage in a single host and when regularly switched between isogenic hosts. Plasmid pB10 was found to be very unstable in Pseudomonas putida H2, and conferred a high cost (c. 20% decrease in fitness relative to the plasmid-free host). H2(pB10) was then evolved under conditions that selected for plasmid maintenance, with or without regular plasmid transfer (host-switching). When tested in the ancestral host, the evolved plasmids were more stable and their cost was significantly reduced (9% and 16% for plasmids from host-switched and nonswitched lineages, respectively). Our findings suggest that IncP-1 plasmids can rapidly adapt to an unfavorable host by improving their overall stability, and that regular conjugative transfer accelerates this process.

Effectiveness of ambon banana stem juice as immunostimulatory against Aeromonas hydrophila infections in catfish Clarias gariepinus

OpenAIRE

Qorie Astria; Sri Nuryati; Kukuh Nirmala; Alimuddin Alimuddin

2017-01-01

ABSTRACT Outbreaks of infectious diseases due to Aeromonas hydrophila in catfish can cause high death rates (80–100%). Fish disease control can be done using phytopharmaceutical to prevent or treat diseases of fish. One of the phytopharmaceutical that known to prevent the fish diseases is ambon banana stem Musa cavendishii var. dwarf Paxton. This study was conducted to test the effectiveness of catfish immersion using banana stem juice as an immunostimulant against bacterial infections A. hyd...

Degenerate primer MOB typing of multiresistant clinical isolates of E. coli uncovers new plasmid backbones.

Science.gov (United States)

Garcillán-Barcia, M Pilar; Ruiz del Castillo, Belén; Alvarado, Andrés; de la Cruz, Fernando; Martínez-Martínez, Luis

2015-01-01

Degenerate Primer MOB Typing is a PCR-based protocol for the classification of γ-proteobacterial transmissible plasmids in five phylogenetic relaxase MOB families. It was applied to a multiresistant E. coli collection, previously characterized by PCR-based replicon-typing, in order to compare both methods. Plasmids from 32 clinical isolates of multiresistant E. coli (19 extended spectrum beta-lactamase producers and 13 non producers) and their transconjugants were analyzed. A total of 95 relaxases were detected, at least one per isolate, underscoring the high potential of these strains for antibiotic-resistance transmission. MOBP12 and MOBF12 plasmids were the most abundant. Most MOB subfamilies detected were present in both subsets of the collection, indicating a shared mobilome among multiresistant E. coli. The plasmid profile obtained by both methods was compared, which provided useful data upon which decisions related to the implementation of detection methods in the clinic could be based. The phylogenetic depth at which replicon and MOB-typing classify plasmids is different. While replicon-typing aims at plasmid replication regions with non-degenerate primers, MOB-typing classifies plasmids into relaxase subfamilies using degenerate primers. As a result, MOB-typing provides a deeper phylogenetic depth than replicon-typing and new plasmid groups are uncovered. Significantly, MOB typing identified 17 plasmids and an integrative and conjugative element, which were not detected by replicon-typing. Four of these backbones were different from previously reported elements. Copyright © 2014 Elsevier Inc. All rights reserved.

Structural analysis of the ParR/parC plasmid partition complex

DEFF Research Database (Denmark)

Møller-Jensen, Jakob; Ringgaard, Simon; Mercogliano, Christopher P

2007-01-01

Accurate DNA partition at cell division is vital to all living organisms. In bacteria, this process can involve partition loci, which are found on both chromosomes and plasmids. The initial step in Escherichia coli plasmid R1 partition involves the formation of a partition complex between the DNA...

Cefotaxime resistant Escherichia coli collected from a healthy volunteer; characterisation and the effect of plasmid loss.

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Miranda Kirchner

Full Text Available In this study 6 CTX-M positive E. coli isolates collected during a clinical study examining the effect of antibiotic use in a human trial were analysed. The aim of the study was to analyse these isolates and assess the effect of full or partial loss of plasmid genes on bacterial fitness and pathogenicity. A DNA array was utilised to assess resistance and virulence gene carriage. Plasmids were characterised by PCR-based replicon typing and addiction system multiplex PCR. A phenotypic array and insect virulence model were utilised to assess the effect of plasmid-loss in E. coli of a large multi-resistance plasmid. All six E. coli carrying bla CTX-M-14 were detected from a single participant and were identical by pulse field gel electrophoresis and MLST. Plasmid profiling and arrays indicated absence of a large multi-drug resistance (MDR F-replicon plasmid carrying blaTEM, aadA4, strA, strB, dfrA17/19, sul1, and tetB from one isolate. Although this isolate partially retained the plasmid it showed altered fitness characteristics e.g. inability to respire in presence of antiseptics, similar to a plasmid-cured strain. However, unlike the plasmid-cured or plasmid harbouring strains, the survival rate for Galleria mellonella infected by the former strain was approximately 5-times lower, indicating other possible changes accompanying partial plasmid loss. In conclusion, our results demonstrated that an apparently healthy individual can harbour bla CTX-M-14 E. coli strains. In one such strain, isolated from the same individual, partial absence of a large MDR plasmid resulted in altered fitness and virulence characteristics, which may have implications in the ability of this strain to infect and any subsequent treatment.

Complete sequences of IncHI1 plasmids carrying bla_CTX-M-1 and qnrS1 in equine Escherichia coli provide new insights into plasmid evolution

DEFF Research Database (Denmark)

Dolejska, Monika; Villa, Laura; Minoia, Marco

2014-01-01

OBJECTIVES: To determine the structure of two multidrug-resistant IncHI1 plasmids carrying blaCTX-M-1 in Escherichia coli isolates disseminated in an equine clinic in the Czech Republic. METHODS: A complete nucleotide sequencing of 239 kb IncHI1 (pEQ1) and 287 kb IncHI1/X1 (pEQ2) plasmids was per...... highlight the structure and evolution of IncHI1 from equine E. coli. A plasmid-mediated sugar metabolic element could play a key role in strain fitness, contributing to the successful dissemination and maintenance of these plasmids in the intestinal microflora of horses....

A conjugative 38 kB plasmid is present in multiple subspecies of Xylella fastidiosa.

Science.gov (United States)

Rogers, Elizabeth E; Stenger, Drake C

2012-01-01

A ≈ 38kB plasmid (pXF-RIV5) was present in the Riv5 strain of Xylella fastidiosa subsp. multiplex isolated from ornamental plum in southern California. The complete nucleotide sequence of pXF-RIV5 is almost identical to that of pXFAS01 from X. fastidiosa subsp. fastidiosa strain M23; the two plasmids vary at only 6 nucleotide positions. BLAST searches and phylogenetic analyses indicate pXF-RIV5 and pXFAS01 share some similarity to chromosomal and plasmid (pXF51) sequences of X. fastidiosa subsp. pauca strain 9a5c and more distant similarity to plasmids from a wide variety of bacteria. Both pXF-RIV5 and pXFAS01 encode homologues of a complete Type IV secretion system involved in conjugation and DNA transfer among bacteria. Mating pair formation proteins (Trb) from Yersinia pseudotuberculosis IP31758 are the mostly closely related non-X. fastidiosa proteins to most of the Trb proteins encoded by pXF-RIV5 and pXFAS01. Unlike many bacterial conjugative plasmids, pXF-RIV5 and pXFAS01 do not carry homologues of known accessory modules that confer selective advantage on host bacteria. However, both plasmids encode seven hypothetical proteins of unknown function and possess a small transposon-associated region encoding a putative transposase and associated factor. Vegetative replication of pXF-RIV5 and pXFAS01 appears to be under control of RepA protein and both plasmids have an origin of DNA replication (oriV) similar to that of pRP4 and pR751 from Escherichia coli. In contrast, conjugative plasmids commonly encode TrfA and have an oriV similar to those found in IncP-1 incompatibility group plasmids. The presence of nearly identical plasmids in single strains from two distinct subspecies of X. fastidiosa is indicative of recent horizontal transfer, probably subsequent to the introduction of subspecies fastidiosa to the United States in the late 19(th) century.

A conjugative 38 kB plasmid is present in multiple subspecies of Xylella fastidiosa.

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Elizabeth E Rogers

Full Text Available A ≈ 38kB plasmid (pXF-RIV5 was present in the Riv5 strain of Xylella fastidiosa subsp. multiplex isolated from ornamental plum in southern California. The complete nucleotide sequence of pXF-RIV5 is almost identical to that of pXFAS01 from X. fastidiosa subsp. fastidiosa strain M23; the two plasmids vary at only 6 nucleotide positions. BLAST searches and phylogenetic analyses indicate pXF-RIV5 and pXFAS01 share some similarity to chromosomal and plasmid (pXF51 sequences of X. fastidiosa subsp. pauca strain 9a5c and more distant similarity to plasmids from a wide variety of bacteria. Both pXF-RIV5 and pXFAS01 encode homologues of a complete Type IV secretion system involved in conjugation and DNA transfer among bacteria. Mating pair formation proteins (Trb from Yersinia pseudotuberculosis IP31758 are the mostly closely related non-X. fastidiosa proteins to most of the Trb proteins encoded by pXF-RIV5 and pXFAS01. Unlike many bacterial conjugative plasmids, pXF-RIV5 and pXFAS01 do not carry homologues of known accessory modules that confer selective advantage on host bacteria. However, both plasmids encode seven hypothetical proteins of unknown function and possess a small transposon-associated region encoding a putative transposase and associated factor. Vegetative replication of pXF-RIV5 and pXFAS01 appears to be under control of RepA protein and both plasmids have an origin of DNA replication (oriV similar to that of pRP4 and pR751 from Escherichia coli. In contrast, conjugative plasmids commonly encode TrfA and have an oriV similar to those found in IncP-1 incompatibility group plasmids. The presence of nearly identical plasmids in single strains from two distinct subspecies of X. fastidiosa is indicative of recent horizontal transfer, probably subsequent to the introduction of subspecies fastidiosa to the United States in the late 19(th century.

Fitness Advantage of mcr-1–Bearing IncI2 and IncX4 Plasmids in Vitro

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Renjie Wu

2018-02-01

Full Text Available The objective of this study was to assess the impact of diverse plasmids bearing colistin resistance gene mcr-1 on host fitness. Forty-seven commensal E. coli isolates recovered from the pig farm where mcr-1 was first identified were screened for mcr-1. mcr-1-bearing plasmids were characterized by sequencing. The fitness impact of mcr-1-bearing plasmids was evaluated by in vitro competition assays. Twenty-seven (57.5% E. coli isolates were positive for mcr-1. The mcr-1 genes were mainly located on plasmids belonging to IncI2 (n = 5, IncX4 (n = 11, IncHI2/ST3 (n = 8, IncFII (n = 2, and IncY (n = 2. InHI2 plasmids also carried other resistance genes (floR, blaCTX−M, and fosA3 and were only detected in isolates from nursery pigs. Sequences of the representative mcr-1–bearing plasmids were almost identical to those of the corresponding plasmid types reported previously. An increase in the fitness of IncI2- and IncX4-carrying strains was observed, while the presence of IncHI2, IncFII and IncY plasmids showed a fitness cost although an insignificant fitness increase was initially observed in IncFII or IncY plasmids-containing strains. Acquisition of IncI2-type plasmid was more beneficial for host E. coli DH5α than either IncHI2 or IncX4 plasmid, while transformants with IncHI2-type plasmid presented a competitive disadvantage against IncI2 or IncX4 plasmid containing strains. In conclusion, IncI2, IncX4, and IncHI2 were the major plasmid types driving the dissemination of mcr-1 in this farm. Increased fitness or co-selection by other antimicrobials might contribute to the further dissemination of the three epidemic mcr-1–positive plasmids (IncI2, IncX4, and IncHI2 in this farm and worldwide.

Imipenem-resistance in Serratia marcescens is mediated by plasmid expression of KPC-2.

Science.gov (United States)

Su, W-Q; Zhu, Y-Q; Deng, N-M; Li, L

2017-04-01

Imipenem is a broad-spectrum carbapenem antibiotic with applications against severe bacterial infections. Here, we describe the identification of imipenem-resistant Serratia marcescens in our hospital and the role of plasmid-mediated KPC-2 expression in imipenem resistance. We used the modified Hodge test to detect carbapenemase produced in imipenem-resistant strains. His resistance can be transferred to E. coli in co-culture tests, which implicates the plasmid in imipenem resistance. PCR amplification from the plasmid identified two products consistent with KPC-2 of 583 and 1050 bp that were also present in E. coli after co-culture. The restriction pattern for both plasmids was identical, supporting the transfer from the S. marcescens isolate to E. coli. Finally, gene sequencing confirmed KPC-2 in the plasmid. Due to the presence of KPC-2 in the imipenem-resistant S. marcescens, we propose that KPC-2 mediates antibiotic resistance in the S. marcescens isolate.

Effect of the atmospheric pressure nonequilibrium plasmas on the conformational changes of plasmid DNA

International Nuclear Information System (INIS)

Yan Xu; He Guangyuan; Shi Mengjun; Gao Xuan; Li Yin; Ma Fengyun; Yu Men; Wang Changdong; Wang Yuesheng; Yang Guangxiao; Zou Fei; Lu Xinpei; Xiong Qing; Xiong Zilan

2009-01-01

The cold atmospheric pressure plasma, which has been widely used for biomedical applications, may potentially affect the conformation of DNA. In this letter, an atmospheric pressure plasma plume is used to investigate its effects on the conformational changes of DNA of plasmid pAHC25. It is found that the plasma plume could cause plasmid DNA topology alteration, resulting in the percentage of the supercoiled plasmid DNA form decreased while that of the open circular and linearized form of plasmid DNA increased as detected by agrose gel electrophoresis. On the other hand, further investigation by using polymerase chain reaction method shows that the atmospheric pressure plasma jet treatments under proper conditions does not affect the genes of the plasmid DNA, which may have potential application in increasing the transformation frequency by genetic engineering.

White Mulberry (Morus alba Foliage Methanolic Extract Can Alleviate Aeromonas hydrophila Infection in African Catfish (Clarias gariepinus

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Atefeh Sheikhlar

2014-01-01

Full Text Available Two experiments were simultaneously conducted with Morus alba (white mulberry foliage extract (MFE as a growth promoter and treatment of Aeromonas hydrophila infection in separate 60 and 30 days trail (Experiments 1 and 2, resp. in African catfish (Clarias gariepinus. In Experiment 1, four diets, control and control supplemented with 2, 5, or 7 g MFE/kg dry matter (DM of diet, were used. In Experiment 2, fish were intraperitoneally infected with Aeromonas hydrophila and fed the same diets as experiment 1 plus additional two diets with or without antibiotic. Results of experiment 1 showed that growth was unaffected by dietary levels of MFE. Treatments with the inclusion of MFE at the levels of 5 and 7 g/Kg DM had no mortality. Red blood cells (RBC, albumin, and total protein were all higher for the treatments fed MFE (5 and 7 g/Kg DM. Results of experiment 2 showed RBC, hemoglobin, hematocrit, globulin, albumin, and total protein improved with the increase in MFE in the infected fish. The dietary MFE at the level of 7 g/kg DM reduced mortality rate. In conclusion, MFE at the level of 7 g/kg DM could be a valuable dietary supplement to cure the infected fish.

First isolation of Aeromonas salmonicida subspecies salmonicida from diseased sea bass, Dicentrarchus labrax (L., cultured in Spain

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Clara Fernández-Álvarez

2016-11-01

Full Text Available This work represents the first description of Aeromonas salmonicida subsp. salmonicida as causative agent of furunculosis in cultured sea bass, Dicentrarchus labrax (L.. Cumulative mortality in affected fish from two floating cages in the Mediterranean coast of Spain was 3.8%. Affected sea bass did not show the typical external signs of furunculosis in the first stages of the disease, however, when the disease progressed, open ulcers appeared on the skin and muscle. Internally, splenomegaly was the only pathological sign observed. Samples from diseased fish were subjected to standardized assays for pathogens screening. Negative results were obtained for parasites and fish viruses. A Gram-stain-negative rod-shaped bacterium was observed in smears from liver, kidney and spleen of all analysed fish. Pure bacterial cultures were recovered from liver, kidney and spleen of all diseased fish sampled during the two different outbreaks. Bacteriological, serological, molecular and chemotaxonomic analysis allowed the identification of the causative agent of sea bass mortalities as Aeromonas salmonicida subsp. salmonicida. The bacterial strains were susceptible to most of antimicrobial agents usually employed in aquaculture except to oxytetracycline. Pathogenicity assays demonstrated that the isolated bacteria were virulent for sea bass, turbot and rainbow trout.

White Mulberry (Morus alba) Foliage Methanolic Extract Can Alleviate Aeromonas hydrophila Infection in African Catfish (Clarias gariepinus)

Science.gov (United States)

Sheikhlar, Atefeh; Alimon, Abd Razk; Daud, Hassan; Saad, Chee R.; Webster, Carl D.; Meng, Goh Yong

2014-01-01

Two experiments were simultaneously conducted with Morus alba (white mulberry) foliage extract (MFE) as a growth promoter and treatment of Aeromonas hydrophila infection in separate 60 and 30 days trail (Experiments 1 and 2, resp.) in African catfish (Clarias gariepinus). In Experiment 1, four diets, control and control supplemented with 2, 5, or 7 g MFE/kg dry matter (DM) of diet, were used. In Experiment 2, fish were intraperitoneally infected with Aeromonas hydrophila and fed the same diets as experiment 1 plus additional two diets with or without antibiotic. Results of experiment 1 showed that growth was unaffected by dietary levels of MFE. Treatments with the inclusion of MFE at the levels of 5 and 7 g/Kg DM had no mortality. Red blood cells (RBC), albumin, and total protein were all higher for the treatments fed MFE (5 and 7 g/Kg DM). Results of experiment 2 showed RBC, hemoglobin, hematocrit, globulin, albumin, and total protein improved with the increase in MFE in the infected fish. The dietary MFE at the level of 7 g/kg DM reduced mortality rate. In conclusion, MFE at the level of 7 g/kg DM could be a valuable dietary supplement to cure the infected fish. PMID:25574488

White mulberry (Morus alba) foliage methanolic extract can alleviate Aeromonas hydrophila infection in African catfish (Clarias gariepinus).

Science.gov (United States)

Sheikhlar, Atefeh; Alimon, Abd Razk; Daud, Hassan; Saad, Chee R; Webster, Carl D; Meng, Goh Yong; Ebrahimi, Mahdi

2014-01-01

Two experiments were simultaneously conducted with Morus alba (white mulberry) foliage extract (MFE) as a growth promoter and treatment of Aeromonas hydrophila infection in separate 60 and 30 days trail (Experiments 1 and 2, resp.) in African catfish (Clarias gariepinus). In Experiment 1, four diets, control and control supplemented with 2, 5, or 7 g MFE/kg dry matter (DM) of diet, were used. In Experiment 2, fish were intraperitoneally infected with Aeromonas hydrophila and fed the same diets as experiment 1 plus additional two diets with or without antibiotic. Results of experiment 1 showed that growth was unaffected by dietary levels of MFE. Treatments with the inclusion of MFE at the levels of 5 and 7 g/Kg DM had no mortality. Red blood cells (RBC), albumin, and total protein were all higher for the treatments fed MFE (5 and 7 g/Kg DM). Results of experiment 2 showed RBC, hemoglobin, hematocrit, globulin, albumin, and total protein improved with the increase in MFE in the infected fish. The dietary MFE at the level of 7 g/kg DM reduced mortality rate. In conclusion, MFE at the level of 7 g/kg DM could be a valuable dietary supplement to cure the infected fish.

3G vector-primer plasmid for constructing full-length-enriched cDNA libraries.

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Zheng, Dong; Zhou, Yanna; Zhang, Zidong; Li, Zaiyu; Liu, Xuedong

2008-09-01

We designed a 3G vector-primer plasmid for the generation of full-length-enriched complementary DNA (cDNA) libraries. By employing the terminal transferase activity of reverse transcriptase and the modified strand replacement method, this plasmid (assembled with a polydT end and a deoxyguanosine [dG] end) combines priming full-length cDNA strand synthesis and directional cDNA cloning. As a result, the number of steps involved in cDNA library preparation is decreased while simplifying downstream gene manipulation, sequencing, and subcloning. The 3G vector-primer plasmid method yields fully represented plasmid primed libraries that are equivalent to those made by the SMART (switching mechanism at 5' end of RNA transcript) approach.

Melanization and Pathogenicity in the Insect, Tenebrio molitor, and the Crustacean, Pacifastacus leniusculus, by Aeromonas hydrophila AH-3

Science.gov (United States)

Noonin, Chadanat; Jiravanichpaisal, Pikul; Söderhäll, Irene; Merino, Susana; Tomás, Juan M.; Söderhäll, Kenneth

2010-01-01

Aeromonas hydrophila is the most common Aeromonas species causing infections in human and other animals such as amphibians, reptiles, fish and crustaceans. Pathogenesis of Aeromonas species have been reported to be associated with virulence factors such as lipopolysaccharides (LPS), bacterial toxins, bacterial secretion systems, flagella, and other surface molecules. Several mutant strains of A. hydrophila AH-3 were initially used to study their virulence in two animal species, Pacifastacus leniusculus (crayfish) and Tenebrio molitor larvae (mealworm). The AH-3 strains used in this study have mutations in genes involving the synthesis of flagella, LPS structures, secretion systems, and some other factors, which have been reported to be involved in A. hydrophila pathogenicity. Our study shows that the LPS (O-antigen and external core) is the most determinant A. hydrophila AH-3 virulence factor in both animals. Furthermore, we studied the immune responses of these hosts to infection of virulent or non-virulent strains of A. hydrophila AH-3. The AH-3 wild type (WT) containing the complete LPS core is highly virulent and this bacterium strongly stimulated the prophenoloxidase activating system resulting in melanization in both crayfish and mealworm. In contrast, the ΔwaaE mutant which has LPS without O-antigen and external core was non-virulent and lost ability to stimulate this system and melanization in these two animals. The high phenoloxidase activity found in WT infected crayfish appears to result from a low expression of pacifastin, a prophenoloxidase activating enzyme inhibitor, and this gene expression was not changed in the ΔwaaE mutant infected animal and consequently phenoloxidase activity was not altered as compared to non-infected animals. Therefore we show that the virulence factors of A. hydrophila are the same regardless whether an insect or a crustacean is infected and the O-antigen and external core is essential for activation of the proPO system

Melanization and pathogenicity in the insect, Tenebrio molitor, and the crustacean, Pacifastacus leniusculus, by Aeromonas hydrophila AH-3.

Directory of Open Access Journals (Sweden)

Chadanat Noonin

Full Text Available Aeromonas hydrophila is the most common Aeromonas species causing infections in human and other animals such as amphibians, reptiles, fish and crustaceans. Pathogenesis of Aeromonas species have been reported to be associated with virulence factors such as lipopolysaccharides (LPS, bacterial toxins, bacterial secretion systems, flagella, and other surface molecules. Several mutant strains of A. hydrophila AH-3 were initially used to study their virulence in two animal species, Pacifastacus leniusculus (crayfish and Tenebrio molitor larvae (mealworm. The AH-3 strains used in this study have mutations in genes involving the synthesis of flagella, LPS structures, secretion systems, and some other factors, which have been reported to be involved in A. hydrophila pathogenicity. Our study shows that the LPS (O-antigen and external core is the most determinant A. hydrophila AH-3 virulence factor in both animals. Furthermore, we studied the immune responses of these hosts to infection of virulent or non-virulent strains of A. hydrophila AH-3. The AH-3 wild type (WT containing the complete LPS core is highly virulent and this bacterium strongly stimulated the prophenoloxidase activating system resulting in melanization in both crayfish and mealworm. In contrast, the ΔwaaE mutant which has LPS without O-antigen and external core was non-virulent and lost ability to stimulate this system and melanization in these two animals. The high phenoloxidase activity found in WT infected crayfish appears to result from a low expression of pacifastin, a prophenoloxidase activating enzyme inhibitor, and this gene expression was not changed in the ΔwaaE mutant infected animal and consequently phenoloxidase activity was not altered as compared to non-infected animals. Therefore we show that the virulence factors of A. hydrophila are the same regardless whether an insect or a crustacean is infected and the O-antigen and external core is essential for activation of the

Comparative Genomics of Rhodococcus equi Virulence Plasmids Indicates Host-Driven Evolution of the vap Pathogenicity Island.

Science.gov (United States)

MacArthur, Iain; Anastasi, Elisa; Alvarez, Sonsiray; Scortti, Mariela; Vázquez-Boland, José A

2017-05-01

The conjugative virulence plasmid is a key component of the Rhodococcus equi accessory genome essential for pathogenesis. Three host-associated virulence plasmid types have been identified the equine pVAPA and porcine pVAPB circular variants, and the linear pVAPN found in bovine (ruminant) isolates. We recently characterized the R. equi pangenome (Anastasi E, et al. 2016. Pangenome and phylogenomic analysis of the pathogenic actinobacterium Rhodococcus equi. Genome Biol Evol. 8:3140-3148.) and we report here the comparative analysis of the virulence plasmid genomes. Plasmids within each host-associated type were highly similar despite their diverse origins. Variation was accounted for by scattered single nucleotide polymorphisms and short nucleotide indels, while larger indels-mostly in the plasticity region near the vap pathogencity island (PAI)-defined plasmid genomic subtypes. Only one of the plasmids analyzed, of pVAPN type, was exceptionally divergent due to accumulation of indels in the housekeeping backbone. Each host-associated plasmid type carried a unique PAI differing in vap gene complement, suggesting animal host-specific evolution of the vap multigene family. Complete conservation of the vap PAI was observed within each host-associated plasmid type. Both diversity of host-associated plasmid types and clonality of specific chromosomal-plasmid genomic type combinations were observed within the same R. equi phylogenomic subclade. Our data indicate that the overall strong conservation of the R. equi host-associated virulence plasmids is the combined result of host-driven selection, lateral transfer between strains, and geographical spread due to international livestock exchanges. © The Author(s) 2017. Published by Oxford University Press on behalf of the Society for Molecular Biology and Evolution.

Characterization of Endogenous Plasmids from Lactobacillus salivarius UCC118▿ †

Science.gov (United States)

Fang, Fang; Flynn, Sarah; Li, Yin; Claesson, Marcus J.; van Pijkeren, Jan-Peter; Collins, J. Kevin; van Sinderen, Douwe; O'Toole, Paul W.

2008-01-01

The genome of Lactobacillus salivarius UCC118 comprises a 1.83-Mb chromosome, a 242-kb megaplasmid (pMP118), and two smaller plasmids of 20 kb (pSF118-20) and 44 kb (pSF118-44). Annotation and bioinformatic analyses suggest that both of the smaller plasmids replicate by a theta replication mechanism. Furthermore, it appears that they are transmissible, although neither possesses a complete set of conjugation genes. Plasmid pSF118-20 encodes a toxin-antitoxin system composed of pemI and pemK homologs, and this plasmid could be cured when PemI was produced in trans. The minimal replicon of pSF118-20 was determined by deletion analysis. Shuttle vector derivatives of pSF118-20 were generated that included the replication region (pLS203) and the replication region plus mobilization genes (pLS208). The plasmid pLS203 was stably maintained without selection in Lactobacillus plantarum, Lactobacillus fermentum, and the pSF118-20-cured derivative strain of L. salivarius UCC118 (strain LS201). Cloning in pLS203 of genes encoding luciferase and green fluorescent protein, and expression from a constitutive L. salivarius promoter, demonstrated the utility of this vector for the expression of heterologous genes in Lactobacillus. This study thus expands the knowledge base and vector repertoire of probiotic lactobacilli. PMID:18390685

Plasmid fingerprinting and virulence gene detection among indigenous strains of salmonella enterica serovar enteritidis

International Nuclear Information System (INIS)

Sajid, S.U.; Schwarz, S.

2009-01-01

Salmonella enterica serovar Enteritidis is an important frequently reported zoonotic pathogen and a common cause of human gastroenteritis worldwide. The highly conserved Serospecific plasmids (SSPs) and Salmonella plasmid virulence (Spv) genes have been shown to mediate extra-intestinal colonization and systemic infection. The objective of current study was to document the presence of SSPs and SpvB/SpvC genes prevailing in the indigenous population of serovar Enteritidis. A total of 48 epidemiologically unrelated strains of Salmonella enteritidis were included in the study. Preparation of plasmids DNA suitable for endonuclease digestion and separation of respective fragments by agarose gel electrophoresis followed previously described protocols. The plasmids of Escherichia coli V517, 1-kbp ladder, and lambda DNA HindIII fragments served as DNA size standards. Transfer of DNA fragments from agarose gels to nitrocellulose membranes was achieved by capillary blot procedure. An ECL labeled 3.6 kbp HindIII fragment of plasmid PRQ 51 was used as probe for SpvB/SpvC gene detection. Plasmid DNA fingerprinting revealed the presence of two different profiles of approximately 55 kbp and 90 kbp and were identified as virulence plasmids by DNA hybridization. The SpvB/SpvC genes were located on HindIII fragments of 3.6 kbp in each of the two types of virulence plasmids. The study confirms the presence of SSPs and SpvB/SpvC genes in indigenous strains of S. enteritidis isolated from Northern Punjab area of Pakistan and substantiate the previous data on such findings from other parts of the world. (author)

Differences in the stability of the plasmids of Yersinia pestis cultures in vitro: impact on virulence

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TC Leal-Balbino

2004-11-01

Full Text Available Plasmid and chromosomal genes encode determinants of virulence for Yersinia pestis, the causative agent of plague. However, in vitro, Y. pestis genome is very plastic and several changes have been described. To evaluate the alterations in the plasmid content of the cultures in vitro and the impact of the alterations to their pathogenicity, three Y. pestis isolates were submitted to serial subculture, analysis of the plasmid content, and testing for the presence of characteristic genes in each plasmid of colonies selected after subculture. Different results were obtained with each strain. The plasmid content of one of them was shown to be stable; no apparent alteration was produced through 32 subcultures. In the other two strains, several alterations were observed. LD50 in mice of the parental strains and the derived cultures with different plasmid content were compared. No changes in the virulence plasmid content could be specifically correlated with changes in the LD50.

Studies on the expression of plasmid-borne genes in the endosymbiotic state of Rhizobium leguminosarum

NARCIS (Netherlands)

Krol, A.J.M.

1982-01-01

The subject matter of the research reported in this thesis is the role of plasmid-borne genes of Rhizobium in symbiosis and nitrogen fixation. Plasmid DNA was isolated from Rhizobium leguminosarum strain PRE and the expression of plasmid DNA in nitrogen

Identification of a Novel Conjugative Plasmid in Mycobacteria That Requires Both Type IV and Type VII Secretion

KAUST Repository

Ummels, R.

2014-09-23

Conjugative plasmids have been identified in a wide variety of different bacteria, ranging from proteobacteria to firmicutes, and conjugation is one of the most efficient routes for horizontal gene transfer. The most widespread mechanism of plasmid conjugation relies on different variants of the type IV secretion pathway. Here, we describe the identification of a novel type of conjugative plasmid that seems to be unique for mycobacteria. Interestingly, while this plasmid is efficiently exchanged between different species of slow-growing mycobacteria, including Mycobacterium tuberculosis, it could not be transferred to any of the fast-growing mycobacteria tested. Genetic analysis of the conjugative plasmid showed the presence of a locus containing homologues of three type IV secretion system components and a relaxase. In addition, a new type VII secretion locus was present. Using transposon insertion mutagenesis, we show that in fact both these secretion systems are essential for conjugation, indicating that this plasmid represents a new class of conjugative plasmids requiring two secretion machineries. This plasmid could form a useful new tool to exchange or introduce DNA in slow-growing mycobacteria. IMPORTANCE: Conjugative plasmids play an important role in horizontal gene transfer between different bacteria and, as such, in their adaptation and evolution. This effect is most obvious in the spread of antibiotic resistance genes. Thus far, conjugation of natural plasmids has been described only rarely for mycobacterial species. In fact, it is generally accepted that M. tuberculosis does not show any recent sign of horizontal gene transfer. In this study, we describe the identification of a new widespread conjugative plasmid that can also be efficiently transferred to M. tuberculosis. This plasmid therefore poses both a threat and an opportunity. The threat is that, through the acquisition of antibiotic resistance markers, this plasmid could start a rapid spread of

TOL plasmid transfer during bacterial conjugation in vitro and rhizoremediation of oil compounds in vivo

International Nuclear Information System (INIS)

Jussila, Minna M.; Zhao, Ji; Suominen, Leena; Lindstroem, Kristina

2007-01-01

Molecular profiling methods for horizontal transfer of aromatics-degrading plasmids were developed and applied during rhizoremediation in vivo and conjugations in vitro. pWW0 was conjugated from Pseudomonas to Rhizobium. The xylE gene was detected both in Rhizobium galegae bv. officinalis and bv. orientalis, but it was neither stably maintained in orientalis nor functional in officinalis. TOL plasmids were a major group of catabolic plasmids among the bacterial strains isolated from the oil-contaminated rhizosphere of Galega orientalis. A new finding was that some Pseudomonas migulae and Pseudomonas oryzihabitans strains harbored a TOL plasmid with both pWW0- and pDK1-type xylE gene. P. oryzihabitans 29 had received the archetypal TOL plasmid pWW0 from Pseudomonas putida PaW85. As an application for environmental biotechnology, the biodegradation potential of oil-polluted soil and the success of bioremediation could be estimated by monitoring changes not only in the type and amount but also in transfer of degradation plasmids. - Horizontal transfer of degradation plasmids in the oil-contaminated rhizosphere reveals the dynamic nature of the intrinsic biodegradation potential

Recombinogenic engineering of conjugative plasmids with fluorescent marker cassettes

DEFF Research Database (Denmark)

Reisner, A.; Molin, Søren; Zechner, E.L.

2002-01-01

An efficient approach for the insertion of fluorescent marker genes with sequence specificity into conjugative plasmids in Escherichia coli is described. For this purpose, homologous recombination of linear double-stranded targeting DNA was mediated by the bacteriophage lambda recombination...... resistance genes and fluorescent markers. The choice of 5' non-homologous extensions in primer pairs used for amplifying the marker cassettes determines the site specificity of the targeting DNA. This methodology is applicable to the modification of all plasmids that replicate in E coli and is not restricted...

RepA and RepB exert plasmid incompatibility repressing the transcription of the repABC operon.

Science.gov (United States)

Pérez-Oseguera, Angeles; Cevallos, Miguel A

2013-11-01

Rhizobium etli CFN42 has a multipartite genome composed of one chromosome and six large plasmids with low copy numbers, all belonging to the repABC plasmid family. All elements essential for replication and segregation of these plasmids are encoded within the repABC operon. RepA and RepB direct plasmid segregation and are involved in the transcriptional regulation of the operon, and RepC is the initiator protein of the plasmid. Here we show that in addition to RepA (repressor) and RepB (corepressor), full transcriptional repression of the operon located in the symbiotic plasmid (pRetCFN42d) of this strain requires parS, the centromere-like sequence, and the operator sequence. However, the co-expression of RepA and RepB is sufficient to induce the displacement of the parental plasmid. RepA is a Walker-type ATPase that self associates in vivo and in vitro and binds specifically to the operator region in its RepA-ADP form. In contrast, RepA-ATP is capable of binding to non-specific DNA. RepA and RepB form high molecular weight DNA-protein complexes in the presence of ATP and ADP. RepA carrying ATP-pocket motif mutations induce full repression of the repABC operon without the participation of RepB and parS. These mutants specifically bind the operator sequence in their ATP or ADP bound forms. In addition, their expression in trans exerts plasmid incompatibility against the parental plasmid. RepA and RepB expressed in trans induce plasmid incompatibility because of their ability to repress the repABC operon and not only by their capacity to distort the plasmid segregation process. Copyright © 2013 Elsevier Inc. All rights reserved.

Enterococcus faecalis Sex Pheromone cCF10 Enhances Conjugative Plasmid Transfer In Vivo.

Science.gov (United States)

Hirt, Helmut; Greenwood-Quaintance, Kerryl E; Karau, Melissa J; Till, Lisa M; Kashyap, Purna C; Patel, Robin; Dunny, Gary M

2018-02-13

Cell-cell communication mediated by peptide pheromones (cCF10 [CF]) is essential for high-frequency plasmid transfer in vitro in Enterococcus faecalis To examine the role of pheromone signaling in vivo , we established either a CF-producing (CF+) recipient or a recipient producing a biologically inactive variant of CF (CF- recipient) in a germfree mouse model 3 days before donor inoculation and determined transfer frequencies of the pheromone-inducible plasmid pCF10. Plasmid transfer was detected in the upper and middle sections of the intestinal tract 5 h after donor inoculation and was highly efficient in the absence of antibiotic selection. The transconjugant/donor ratio reached a maximum level approaching 1 on day 4 in the upper intestinal tract. Plasmid transfer was significantly lower with the CF- recipient. While rescue of the CF- mating defect by coculture with CF+ recipients is easily accomplished in vitro , no extracellular complementation occurred in vivo This suggests that most pheromone signaling in the gut occurs between recipient and donor cells in very close proximity. Plasmid-bearing cells (donors plus transconjugants) steadily increased in the population from 0.1% after donor inoculation to about 10% at the conclusion of the experiments. This suggests a selective advantage of pCF10 carriage distinct from antibiotic resistance or bacteriocin production. Our results demonstrate that pheromone signaling is required for efficient pCF10 transfer in vivo In the absence of CF+ recipients, a low level of transfer to CF- recipients occurred in the gut. This may result from low-level host-mediated induction of the donors in the gastrointestinal (GI) tract, similar to that previously observed in serum. IMPORTANCE Horizontal gene transfer is a major factor in the biology of Enterococcus faecalis , an important nosocomial pathogen. Previous studies showing efficient conjugative plasmid transfer in the gastrointestinal (GI) tracts of experimental animals did

Standardized Cloning and Curing of Plasmids

DEFF Research Database (Denmark)

Lauritsen, Ida; Kim, Se Hyeuk; Porse, Andreas

2018-01-01

and exchange of genetic parts in the Standard European Vectors Architecture (SEVA) vector system. Additionally, to facilitate rapid testing and iterative bioengineering using different vector designs, we provide a one-step protocol for a universal CRISPR-Cas9-based plasmid curing system (pFREE) and demonstrate...

Characterization of a plasmid carrying cat, ermB and tetS genes in a foodborne Listeria monocytogenes strain and uptake of the plasmid by cariogenic Streptococcus mutans

DEFF Research Database (Denmark)

Li, Lili; Olsen, Rikke Heidemann; Shi, Lei

2016-01-01

A multi-drug resistant (MDR) Listeria monocytogenes isolate (serotype 1/2c) was recovered from a quick-frozen rice flour product collected from Langfang city in northern China. PCR screening identified the presence of cat, ermB and tetS genes. The plasmid profile of the strain showed the presence...... of an approximately 22.4-kb plasmid. Curing of this plasmid resulted in the loss of cat, ermB and tetS genes and increased susceptibility to several antibiotics, suggesting the involvement of the plasmid in multiple antibiotic resistances. Moreover, the plasmid was able to be uptaken by human oral pathogen...

Functionalized tetrapod-like ZnO nanostructures for plasmid DNA purification, polymerase chain reaction and delivery

International Nuclear Information System (INIS)

Nie Leng; Gao Lizeng; Yan Xiyun; Wang Taihong

2007-01-01

Functionalized tetrapodal ZnO nanostructures are tested in plasmid DNA experiments (1) as a solid-phase adsorbent for plasmid DNA purification (2) as improving reagents in a polymerase chain reaction (PCR) and (3) as novel carriers for gene delivery. The amino-modification, the tetrapod-like shape of the nanostructure and its high biocompatibility all contribute to measurements showing promise for applications. A sol-gel method is used for silica coating and amino-modification. Plasmid DNA is purified through reversible conjugations of amino-modified ZnO tetrapods with DNA. Also, as additional reagents, functionalized tetrapods are shown to improve the amount of PCR product. For transfection, ZnO tetrapods provide some protection against deoxyribonuclease cleavage of plasmid DNA and deliver plasmid DNA into cells with little cytotoxicity

Aeromonas salmonicida - Epidemiology, whole genome sequencing, detection and in vivo imaging

DEFF Research Database (Denmark)

Bartkova, Simona

causes problems in sea reared rainbow trout (Oncorhynchus mykiss) production. Outbreaks occur repeatedly during stressful conditions such as elevated temperatures, in spite of commercial vaccines being applied. Besides seemingly lacking adequate protection, the vaccines also produce undesirable side...... of the concerns regarding A. salmonicida. First, we focused on investigation of the route of entry and initial dissemination of A. salmonicida in fish. This was done by tracing the bacterium using in vivo bioluminescence imaging. A Danish strain was transformed with a plasmid vector containing a green...... was subsequently turned to finding a sensitive method for detecting A. salmonicida in infected and possible carrier fish. For this, a previously developed quantitative real-time polymerase chain reaction (real-time PCR) targeting the aopP gene located on A. salmonicida plasmid pAsal1 was assessed. The real...

A one-step miniprep for the isolation of plasmid DNA and lambda phage particles.

Directory of Open Access Journals (Sweden)

George Lezin

Full Text Available Plasmid DNA minipreps are fundamental techniques in molecular biology. Current plasmid DNA minipreps use alkali and the anionic detergent SDS in a three-solution format. In addition, alkali minipreps usually require additional column-based purification steps and cannot isolate other extra-chromosomal elements, such as bacteriophages. Non-ionic detergents (NIDs have been used occasionally as components of multiple-solution plasmid DNA minipreps, but a one-step approach has not been developed. Here, we have established a one-tube, one-solution NID plasmid DNA miniprep, and we show that this approach also isolates bacteriophage lambda particles. NID minipreps are more time-efficient than alkali minipreps, and NID plasmid DNA performs better than alkali DNA in many downstream applications. In fact, NID crude lysate DNA is sufficiently pure to be used in digestion and sequencing reactions. Microscopic analysis showed that the NID procedure fragments E. coli cells into small protoplast-like components, which may, at least in part, explain the effectiveness of this approach. This work demonstrates that one-step NID minipreps are a robust method to generate high quality plasmid DNA, and NID approaches can also isolate bacteriophage lambda particles, outperforming current standard alkali-based minipreps.

Autonomous replication of plasmids bearing monkey DNA origin-enriched sequences

International Nuclear Information System (INIS)

Frappier, L.; Zannis-Hadjopoulos, M.

1987-01-01

Twelve clones of origin-enriched sequences (ORS) isolated from early replicating monkey (CV-1) DNA were examined for transient episomal replication in transfected CV-1, COS-7, and HeLa cells. Plasmid DNA was isolated at time intervals after transfection and screened by the Dpn I resistance assay or by the bromodeoxyuridine substitution assay to differentiate between input and replicated DNA. The authors have identified four monkey ORS (ORS3, -8, -9, and -12) that can support plasmid replication in mammalian cells. This replication is carried out in a controlled and semiconservative manner characteristic of mammalian replicons. ORS replication was most efficient in HeLa cells. Electron microscopy showed ORS8 and ORS12 plasmids of the correct size with replication bubbles. Using a unique restriction site in ORS12, we have mapped the replication bubble within the monkey DNA sequence

Plasmids replicatable in Bacillus subtilis, E. coli and lactic acid streptococcus bacteria

NARCIS (Netherlands)

Kok, Jan; Maat, Jan; van der Vossen, Josephus Mauritius; Venema, Gerard

1997-01-01

The claimed invention is drawn to a recombinant plasmid which can replicate in Bacillus subtilis, Escherichia coli, and lactic acid Streptococcus bacteria comprising the replication of origin from Streptococcus cremoris plasmid pWV01 as its origin of replication, in addition to coding marker genes

Construction of pTM series plasmids for gene expression in Brucella species.

Science.gov (United States)

Tian, Mingxing; Qu, Jing; Bao, Yanqing; Gao, Jianpeng; Liu, Jiameng; Wang, Shaohui; Sun, Yingjie; Ding, Chan; Yu, Shengqing

2016-04-01

Brucellosis, the most common widespread zoonotic disease, is caused by Brucella spp., which are facultative, intracellular, Gram-negative bacteria. With the development of molecular biology techniques, more and more virulence-associated factors have been identified in Brucella spp. A suitable plasmid system is an important tool to study virulence genes in Brucella. In this study, we constructed three constitutive replication plasmids (pTM1-Cm, pTM2-Amp, and pTM3-Km) using the replication origin (rep) region derived from the pBBR1-MCS vector. Also, a DNA fragment containing multiple cloning sites (MCSs) and a terminator sequence derived from the pCold vector were produced for complementation of the deleted genes. Besides pGH-6×His, a plasmid containing the groE promoter of Brucella spp. was constructed to express exogenous proteins in Brucella with high efficiency. Furthermore, we constructed the inducible expression plasmid pZT-6×His, containing the tetracycline-inducible promoter pzt1, which can induce expression by the addition of tetracycline in the Brucella culture medium. The constructed pTM series plasmids will play an important role in the functional investigation of Brucella spp. Copyright © 2016 Elsevier B.V. All rights reserved.

Structural and functional analysis of the kid toxin protein from E. coli Plasmid R1

NARCIS (Netherlands)

Hargreaves, D.; Santos-Sierra, S.; Giraldo, R.; Sabariegos-Jareño, R.; de la Cueva-Méndez, G.; Boelens, R.|info:eu-repo/dai/nl/070151407; Díaz-Orejas, R.; Rafferty, J.B.

2002-01-01

We have determined the structure of Kid toxin protein from E. coli plasmid R1 involved in stable plasmid inheritance by postsegregational killing of plasmid-less daughter cells. Kid forms a two-component system with its antagonist, Kis antitoxin. Our 1.4 Å crystal structure of Kid reveals a 2-fold

Evaluation of the effect of non-B DNA structures on plasmid integrity via accelerated stability studies.

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Ribeiro, S C; Monteiro, G A; Prazeres, D M F

2009-04-01

Plasmid biopharmaceuticals are a new class of medicines with an enormous potential. Attempts to increase the physical stability of highly purified supercoiled (SC) plasmid DNA in pharmaceutical aqueous solutions have relied on: (i) changing the DNA sequence, (ii) improving manufacturing to reduce deleterious impurities and initial DNA damage, and (iii) controlling the storage medium characteristics. In this work we analyzed the role of secondary structures on the degradation of plasmid molecules. Accelerated stability experiments were performed with SC, open circular (OC) and linear (L) isoforms of three plasmids which differed only in the "single-strandlike" content of their polyadenylation (poly A) signals. We have proved that the presence of more altered or interrupted (non-B) DNA secondary structures did not directly translate into an easier strand scission of the SC isoforms. Rather, those unusual structures imposed a lower degree of SC in the plasmids, leading to an increase in their resistance to thermal degradation. However, this behavior was reversed when the relaxed or L isoforms were tested, in which case the absence of SC rendered the plasmids essentially double-stranded. Overall, this work suggests that plasmid DNA sequence and secondary structures should be taken into account in future investigations of plasmid stability during prolonged storage.

trans-Acting Virulence Functions of the Octopine Ti Plasmid from Agrobacterium tumefaciens

NARCIS (Netherlands)

Hille, Jacques; Kan, Jan van; Schilperoort, Rob

1984-01-01

All Ti plasmid-encoded virulence functions that were studied act in trans. An octopine Ti plasmid-specific vir operon, called vir-O, located on an EcoRI restriction fragment has been characterized. Sequences with promoter activity in Escherichia coli were identified for a second vir operon, called

Frozen White-Leg Shrimp (Litopenaeus vannamei) in Korean Markets as a Source of Aeromonas spp. Harboring Antibiotic and Heavy Metal Resistance Genes.

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De Silva, Benthotage C J; Hossain, Sabrina; Dahanayake, Pasan S; Heo, Gang-Joon

2018-05-24

As the most consumed shrimp variety, white-leg shrimp (Litopenaeus vannamei) owns a high market demand in Korea. This study sought to screen the frozen white-leg shrimp for Aeromonas spp. harboring antimicrobial and heavy metal resistance characteristics. A total of 44 Aeromonas spp. strains were isolated and tested for antibiotic susceptibility and heavy metal tolerance followed by PCR-based detection of resistance genes and integrons. It was observed that resistance to ampicillin and oxacillin was 100% among isolates. Besides, 95%, 89%, 86%, 80%, 66%, and 43% of the isolates were resistant to nalidixic acid, tetracycline, cephalothin, streptomycin, trimethoprim-sulfamethoxazole, and imipenem, respectively, and less resistance to other antibiotics was also observed. Cr resistance was the highest (91%) among five heavy metals tested, whereas 57%, 32%, 20%, and 9% of the isolates were tolerant to Cu, Pb, Cd, and Hg, respectively. The PCR assays implied the presence of qnrB, qnrS, tetA, tetE, aac(6')-Ib, and aphAI-IAB, and intI1 genes among 80%, 77%, 18%, 30%, 9%, 0.25%, and 82% of the isolates, respectively. There were 35 (80%) integron 1-positive isolates harboring qacE2, dfrA1, orfC, orfD, aadB, catB3, oxa-10, and aadA1 genes in varying combinations. In addition, heavy metal resistance genes, CopA, merA, and CzcA were positive in 9%, 7%, and 27% of the isolates, respectively. According to these outcomes, the frozen white-leg shrimp in Korean markets can be suggested as a source of multidrug and heavy metal-resistant Aeromonas spp. that carries genetic determinants.

Tn5-induced pBS286 plasmid mutations blocking early stages of napthalene oxidation

International Nuclear Information System (INIS)

Kosheleva, I.A.; Tsoi, T.V.; Ivashina, T.V.; Selifonov, S.A.; Starovoitov, I.I.; Boronin, A.M.

1988-01-01

The authors present data on the further analysis of the structural and functional organization of the nah region of plasmid pBS286 controlling the constitutive oxidation of naphthalene by Pseudomonas putida cells. They have studied Tn5-induced mutations blocking early stages of naphthalene oxidation. They present and discuss data providing evidence that, in contrast to plasmid NAH7, the mechanism of regulation of the nahl operon of plasmid NPL-1, the parent plasmid of plasmid pBS286, with inducible synthesis of naphthalene dioxygenase can include elements of a negative control with participation of the regulatory locus R, located proximal to the structural nah genes and closely linked to or overlapped by the inverted control DNA segment (4.2 kb). They also present data on the possibility of regulation of the activity of the catechol-splitting meta-pathway genes with the participation of products of early stages of naphthalene oxidation

Minimal and contributing sequence determinants of the cis-acting locus of transfer (clt) of streptomycete plasmid pIJ101 occur within an intrinsically curved plasmid region.

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Ducote, M J; Prakash, S; Pettis, G S

2000-12-01

Efficient interbacterial transfer of streptomycete plasmid pIJ101 requires the pIJ101 tra gene, as well as a cis-acting plasmid function known as clt. Here we show that the minimal pIJ101 clt locus consists of a sequence no greater than 54 bp in size that includes essential inverted-repeat and direct-repeat sequences and is located in close proximity to the 3' end of the korB regulatory gene. Evidence that sequences extending beyond the minimal locus and into the korB open reading frame influence clt transfer function and demonstration that clt-korB sequences are intrinsically curved raise the possibility that higher-order structuring of DNA and protein within this plasmid region may be an inherent feature of efficient pIJ101 transfer.

In vitro antimicrobial activity of ethanolic extracts obtained from Ficus spp. leaves against the fish pathogen Aeromonas hydrophila

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Tkachenko Halyna

2016-12-01

Full Text Available The main goal of this study was to determine in vitro antimicrobial activity of ethanolic extracts obtained from the leaves of various Ficus species against Aeromonas hydrophila isolated locally from infected rainbow trout (Oncorhynchus mykiss Walbaum with the aim of providing scientific rationale for the use of the plant in the treatment of bacterial infections induced by Aeromonas spp. in fish. Antimicrobial susceptibility testing was done on Muller-Hinton agar with the disc diffusion method. In the present study, most ethanolic extracts proved effective against the A. hydrophila tested, with 10-12 mm inhibition zones observed. A. hydrophila demonstrated the highest susceptibility to F. pumila. Among various species of Ficus with moderate activity against A. hydrophila, the highest antibacterial activities were noted for F. benghalensis, F. benjamina, F. deltoidea, F. hispida, and F. lyrata. Thus, Ficus can be used as a natural antiseptic and antimicrobial agent in veterinary practice. Further investigations need to be conducted to isolate and identify the bioactive compounds that can then be subjected to detailed pharmacological studies and the development of clinical applications. The alarming rate of increasing resistance in bacterial pathogens in aquaculture environments means that medicinal plants with antibacterial properties are very important as natural resources of new active compounds.

Cloning in Streptococcus lactis of plasmid-mediated UV resistance and effect on prophage stability

International Nuclear Information System (INIS)

Chopin, M.C.; Chopin, A.; Rouault, A.; Simon, D.

1986-01-01

Plasmid pIL7 (33 kilobases) from Streptococcus lactis enhances UV resistance and prophage stability. A 5.4-kilobase pIL7 fragment carrying genes coding for both characters was cloned into S. lactis, using plasmid pHV1301 as the cloning vector. The recombinant plasmid was subsequently transferred to three other S. lactis strains by transformation or protoplast fusion. Cloned genes were expressed in all tested strains

Plasmid DNA damage by heavy ions at spread-out Bragg peak energies

NARCIS (Netherlands)

Dang, H. M.; van Goethem, M. J.; van der Graaf, E. R.; Brandenburg, S.; Hoekstra, R.; Schlatholter, T.

2010-01-01

Interaction of ionizing radiation with plasmid DNA can lead to formation of single strand breaks, double strand breaks and clustered lesions. We have investigated the response of the synthetic plasmid pBR322 in aqueous solution upon irradiation with (12)C ions under spread-out Bragg peak conditions

Presence and analysis of plasmids in human and animal associated Arcobacter species

DEFF Research Database (Denmark)

Douidah, Laid; De Zutter, Lieven; Van Nieuwerburgh, Filip

2014-01-01

coding information, which contrasts to the 20 to 30% for the small plasmids. Some of the open reading frames showed a high homology to putative conserved domains found in other related organisms, such as replication, mobilization and genes involved in type IV secretion system. The large plasmid carried...

Virus-sized self-assembling lamellar complexes between plasmid DNA and cationic micelles promote gene transfer

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Pitard, Bruno; Aguerre, Olivier; Airiau, Marc; Lachagès, Anne-Marie; Boukhnikachvili, Tsiala; Byk, Gérardo; Dubertret, Catherine; Herviou, Christian; Scherman, Daniel; Mayaux, Jean-François; Crouzet, Joël

1997-01-01

Gene therapy is based on the vectorization of genes to target cells and their subsequent expression. Cationic amphiphile-mediated delivery of plasmid DNA is the nonviral gene transfer method most often used. We examined the supramolecular structure of lipopolyamine/plasmid DNA complexes under various condensing conditions. Plasmid DNA complexation with lipopolyamine micelles whose mean diameter was 5 nm revealed three domains, depending on the lipopolyamine/plasmid DNA ratio. These domains respectively corresponded to negatively, neutrally, and positively charged complexes. Transmission electron microscopy and x-ray scattering experiments on complexes originating from these three domains showed that although their morphology depends on the lipopolyamine/plasmid DNA ratio, their particle structure consists of ordered domains characterized by even spacing of 80 Å, irrespective of the lipid/DNA ratio. The most active lipopolyamine/DNA complexes for gene transfer were positively charged. They were characterized by fully condensed DNA inside spherical particles (diameter: 50 nm) sandwiched between lipid bilayers. These results show that supercoiled plasmid DNA is able to transform lipopolyamine micelles into a supramolecular organization characterized by ordered lamellar domains. PMID:9405626

Sequence analysis and characterization of rolling-circle replicating plasmid pVCM01 from Salmonella enterica

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Penido, A. F. B.

2013-12-01

Full Text Available Aims: Characterization of cryptic plasmid pVCM01 (accession number JX133088 isolated from Salmonella enterica Enteritidis. Methodology and results: The complete sequence of pVCM01 was obtained. This plasmid possesses 1981 bp, with G+C content of 57% in agreement of the range of Salmonella genomic DNA. pVCM01 has a high degree of similarity to pB and pJ plasmids. It possesses six main open reading frames, only one have a very high degree of amino acid identity with protein involved in the rolling-circle-like replication (RCR. Based on the sequence similarities, pVCM01 plasmid belonged to the pC194/pUB110 rolling-circle replicating plasmid family. The Rep pVCM01 possesses the motifs: FLTLTVRN, HPHFHTL, SGDGYVKHERW, which were present in all Rep proteins. Conclusion, significance and impact of study: The small size of pVCM01 plasmid and its stability in E. coli cells, make it an attractive candidate to develop new vectors, such as cloning and/or expression vector.

The large universal Pantoea plasmid LPP-1 plays a major role in biological and ecological diversification

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De Maayer Pieter

2012-11-01

Full Text Available Abstract Background Pantoea spp. are frequently isolated from a wide range of ecological niches and have various biological roles, as plant epi- or endophytes, biocontrol agents, plant-growth promoters or as pathogens of both plant and animal hosts. This suggests that members of this genus have undergone extensive genotypic diversification. One means by which this occurs among bacteria is through the acquisition and maintenance of plasmids. Here, we have analyzed and compared the sequences of a large plasmid common to all sequenced Pantoea spp. Results and discussion The Large PantoeaPlasmids (LPP-1 of twenty strains encompassing seven different Pantoea species, including pathogens and endo-/epiphytes of a wide range of plant hosts as well as insect-associated strains, were compared. The LPP-1 plasmid sequences range in size from ~281 to 794 kb and carry between 238 and 750 protein coding sequences (CDS. A core set of 46 proteins, encompassing 2.2% of the total pan-plasmid (2,095 CDS, conserved among all LPP-1 plasmid sequences, includes those required for thiamine and pigment biosynthesis. Phylogenetic analysis reveals that these plasmids have arisen from an ancestral plasmid, which has undergone extensive diversification. Analysis of the proteins encoded on LPP-1 also showed that these plasmids contribute to a wide range of Pantoea phenotypes, including the transport and catabolism of various substrates, inorganic ion assimilation, resistance to antibiotics and heavy metals, colonization and persistence in the host and environment, pathogenesis and antibiosis. Conclusions LPP-1 is universal to all Pantoea spp. whose genomes have been sequenced to date and is derived from an ancestral plasmid. LPP-1 encodes a large array of proteins that have played a major role in the adaptation of the different Pantoea spp. to their various ecological niches and their specialization as pathogens, biocontrol agents or benign saprophytes found in many diverse

[Isolation and characterization of petroleum catabolic broad-host-range plasmids from Shen-Fu wastewater irrigation zone].

Science.gov (United States)

Wang, Ya-Fei; Wang, Ya-Fei; Li, Hui; Li, Xiao-Bin

2013-11-01

Based on triparental mating, we isolated a total of eight broad host range (BHR) petroleum hydrocarbon catabolic plasmids from the soils, sediments, and wastewater samples in the Shen-Fu irrigation zone. The antibiotic resistance of the plasmids was tested, and then, the plasmids were transferred to Escherichia coli EC100. The plasmids carrying no antibiotic resistance were tagged by miniTn5 transposon consisting of antibiotic resistant genes. The PCR-based incompatibility test revealed that the pS3-2C and pS4-6G belonged to Inc P group, the pS3-2G, pW22-3G, and pA15-7G belonged to Inc N group, the pS7-2G was identified as Inc W plasmid, and the pA23-1G and pA10-1C were placed into Inc Q group. By adopting the reported PCR amplification methods of petroleum hydrocarbon-degrading catabolic genes, the petroleum-degrading capability of these BHR plasmids were preliminarily analyzed. The plasmids pS3-2G, pS7-2G, pA23-1G, pW22-3G, and pA10-1C carried aromatic ring- hydroxylating dioxygenase gene phdA and toluene monooxygenase gene touA; the plasmid pA15-7G carried touA and toluene dioxygenase gene tod; the plasmid pS3-2C carried ben, phdA, and tod; whereas the pS4-6G only carried ben. The host range test showed that all the isolated plasmids except pS3-2C could be transferred and maintained stably in the representative strains Agrobacterium tumefaciens C58, Cupriavidus necator JMP228, and E. coli EC100 of the alpha-, beta-, and gamma-Proteobacteria, respectively.

Identification of Two Pathogenic Aeromonas Species Isolated during Production Related Epizootics from Juvenile Burbot Lota lota maculosa.

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Terrazas, Marc M; Anderson, Cort L; Jacobs, Sarah J; Cain, Kenneth D

2018-05-25

In response to population declines of Burbot Lota lota maculosa, conservation aquaculture methods have been developed for this species. In general, Burbot are relatively resistant to many salmonid pathogens; however, cultured juvenile Burbot have experienced periodic epizootic disease outbreaks during production. A series of trials were conducted to determine the virulence of select bacteria isolated from juvenile Burbot following outbreaks that occurred in 2012 and 2013 at the University of Idaho's Aquaculture Research Institute. Initial clinical diagnostics and sampling resulted in the isolation of numerous putative bacterial pathogens. To determine which bacteria were the most likely causative agents contributing to these epizootics, juvenile Burbot were injectied intraperitoneally (IP) with select bacteria in log phase growth. Mortality associated with specific isolates was recorded, and more comprehensive challenges followed this initial screening. These challenges used side-by-side IP and immersion methods to expose Burbot to potential pathogens. The challenges resulted in significantly higher mortalities in fish following IP injection of two Aeromonas sp. isolates compared to controls (P ≤ 0.01), but no difference in mortality for immersion challenged groups was observed (P = 0.42). Results demonstrate that two isolates (Aeromonas sp.) cultured from the epizootics are virulent to Burbot. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

Vibrios and Aeromonas.

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Holmberg, S D

1988-09-01

There are many similarities in the Vibrionaceae that cause human illness in the United States (see Table 1). Vibrios are characteristically indigenous to marine, estuarine, and brackish environments. They are distributed mainly in Gulf of Mexico coastal water, and these organisms "bloom" when the water is warm. Outbreaks of disease in humans frequently occur in summer, coinciding with multiplication of vibrios in warm water. Sporadic cases and small outbreaks of cholera continue to occur in persons living on or near the Gulf of Mexico, but infection in most persons is unrecognized. In fact, more serious and frequent illnesses result from V. vulnificus wound infections and from gastroenteritis caused by vibrios other than V. cholerae 01. Underlying hepatic or neoplastic disease (especially leukemia) apparently increases the likelihood and severity of illnesses caused by V. vulnificus and Aeromonas. Some Vibrionaceae produce clinical illness by means of enterotoxins identical or similar to cholera toxin. For many others, hemolysins, cytotoxins, and other exotoxins are necessary to produce disease; the importance of these virulence factors often is not known or the importance of these virulence factors often is not known or is of doubtful significance. Also, purported pathogenicity as demonstrated by animal models, such as fluid accumulation in ligated ileal loops, is quite nonspecific and needs to be interpreted cautiously. For Plesiomonas, a mode of pathogenesis has not been discovered. Eating raw shellfish (frequently raw oysters) has been linked epidemiologically to enteric infections with most of these bacteria; foreign travel and exposure to seawater are other frequently observed epidemiologic associations with infection. Foreign travel, particularly to the Yucatan Peninsula of Mexico, has been strongly associated with the acquisition of non-01 V. cholerae and Plesiomonas organisms. Most Vibrionaceae in the United States are susceptible in vitro--and illnesses

Transformation of UV-hypersensitive Chinese hamster ovary cell mutants with UV-irradiated plasmids

International Nuclear Information System (INIS)

Nairn, R.S.; Humphrey, R.M.; Adair, G.M.

1988-01-01

Transfection of UV-hypersensitive, DNA repair-deficient Chinese hamster ovary (CHO) cell lines and parental, repair-proficient CHO cells with UV-irradiated pHaprt-1 or pSV2gpt plasmids resulted in different responses by recipient cell lines to UV damage in transfected DNA. Unlike results reported for human cells, UV irradiation of transfecting DNA did not stimulate genetic transformation of CHO recipient cells. In repair-deficient CHO cells, proportionally fewer transformants were produced with increasing UV damage than in repair-proficient cells in transfections with UV-irradiated hamster adenine phosphoribosyltransferase (APRT) gene contained in plasmid pHaprt-1. Transfection of CHO cells with UV-irradiated pSV2gpt resulted in neither decline in transformation frequencies in repair-deficient cell lines relative to repair-proficient cells nor stimulation of genetic transformation by UV damage in the plasmid. Blot hybridization analysis of DNA samples isolated from transformed cells showed no dramatic changes in copy number or arrangement of transfected plasmid DNA with increasing UV dose. The authors conclude responses of recipient cells to UV-damaged transfecting plasmids depend on type of recipient cell and characteristics of the genetic sequence used for transfection. (author)

Structures of actin-like ParM filaments show architecture of plasmid-segregating spindles.

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Bharat, Tanmay A M; Murshudov, Garib N; Sachse, Carsten; Löwe, Jan

2015-07-02

Active segregation of Escherichia coli low-copy-number plasmid R1 involves formation of a bipolar spindle made of left-handed double-helical actin-like ParM filaments. ParR links the filaments with centromeric parC plasmid DNA, while facilitating the addition of subunits to ParM filaments. Growing ParMRC spindles push sister plasmids to the cell poles. Here, using modern electron cryomicroscopy methods, we investigate the structures and arrangements of ParM filaments in vitro and in cells, revealing at near-atomic resolution how subunits and filaments come together to produce the simplest known mitotic machinery. To understand the mechanism of dynamic instability, we determine structures of ParM filaments in different nucleotide states. The structure of filaments bound to the ATP analogue AMPPNP is determined at 4.3 Å resolution and refined. The ParM filament structure shows strong longitudinal interfaces and weaker lateral interactions. Also using electron cryomicroscopy, we reconstruct ParM doublets forming antiparallel spindles. Finally, with whole-cell electron cryotomography, we show that doublets are abundant in bacterial cells containing low-copy-number plasmids with the ParMRC locus, leading to an asynchronous model of R1 plasmid segregation.

Two highly divergent lineages of exfoliative toxin B-encoding plasmids revealed in impetigo strains of Staphylococcus aureus.

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Botka, Tibor; Růžičková, Vladislava; Svobodová, Karla; Pantůček, Roman; Petráš, Petr; Čejková, Darina; Doškař, Jiří

2017-09-01

Exfoliative toxin B (ETB) encoded by some large plasmids plays a crucial role in epidermolytic diseases caused by Staphylococcus aureus. We have found as yet unknown types of etb gene-positive plasmids isolated from a set of impetigo strains implicated in outbreaks of pemphigus neonatorum in Czech maternity hospitals. Plasmids from the strains of clonal complex CC121 were related to archetypal plasmid pETB TY4 . Sharing a 33-kb core sequence including virulence genes for ETB, EDIN C, and lantibiotics, they were assigned to a stand-alone lineage, named pETB TY4 -based plasmids. Differing from each other in the content of variable DNA regions, they formed four sequence types. In addition to them, a novel unique plasmid pETB608 isolated from a strain of ST130 was described. Carrying conjugative cluster genes, as well as new variants of etb and edinA genes, pETB608 could be regarded as a source of a new lineage of ETB plasmids. We have designed a helpful detection assay, which facilitates the precise identification of the all described types of ETB plasmids. Copyright © 2017 Elsevier GmbH. All rights reserved.

Growth dependence of conjugation explains limited plasmid invasion in biofilms: an individual‐based modelling study

DEFF Research Database (Denmark)

Merkey, Brian; Lardon, Laurent; Seoane, Jose Miguel

2011-01-01

Plasmid invasion in biofilms is often surprisingly limited in spite of the close contact of cells in a biofilm. We hypothesized that this poor plasmid spread into deeper biofilm layers is caused by a dependence of conjugation on the growth rate (relative to the maximum growth rate) of the donor......, we find that invasion of a resident biofilm is indeed limited when plasmid transfer depends on growth, but not so in the absence of growth dependence. Using sensitivity analysis we also find that parameters related to timing (i.e. a lag before the transconjugant can transfer, transfer proficiency...... and scan speed) and spatial reach (EPS yield, conjugal pilus length) are more important for successful plasmid invasion than the recipients' growth rate or the probability of segregational loss. While this study identifies one factor that can limit plasmid invasion in biofilms, the new individual...

Development and application of a general plasmid reference material for GMO screening.

Science.gov (United States)

Wu, Yuhua; Li, Jun; Wang, Yulei; Li, Xiaofei; Li, Yunjing; Zhu, Li; Li, Jun; Wu, Gang

The use of analytical controls is essential when performing GMO detection through screening tests. Additionally, the presence of taxon-specific sequences is analyzed mostly for quality control during GMO detection. In this study, 11 commonly used genetic elements involving three promoters (P-35S, P-FMV35S and P-NOS), four marker genes (Bar, NPTII, HPT and Pmi), and four terminators (T-NOS, T-35S, T-g7 and T-e9), together with the reference gene fragments from six major crops of maize, soybean, rapeseed, rice, cotton and wheat, were co-integrated into the same single plasmid to construct a general reference plasmid pBI121-Screening. The suitability test of pBI121-Screening plasmid as reference material indicated that the non-target sequence on the pBI121-Screening plasmid did not affect the PCR amplification efficiencies of screening methods and taxon-specific methods. The sensitivity of screening and taxon-specific assays ranged from 5 to 10 copies of pBI121-Screening plasmid, meeting the sensitivity requirement of GMO detection. The construction of pBI121-Screening solves the lack of a general positive control for screening tests, thereby reducing the workload and cost of preparing a plurality of the positive control. Copyright © 2016 Elsevier B.V. All rights reserved.

[Construction and identification of eukaryotic plasmid pGC-silencer-U6/Neo/GFP/ABCG2].

Science.gov (United States)

Yu, Yanping; Zhang, Song; Kong, Weijia

2010-09-01

To construct three short hairpin RNA (shRNA) interference expression plasmid vectors of human ABCG2 gene, to assay the expression of ABCG2 in a human nasopharyngeal carcinoma (NPC) cell line, CEN-2 cell line, and to detect the RNAi effect of shRNA. Targeting ABCG2 gene sequence, three plasmid expression vectors coding for shRNA and a control vector containing random DNA fragment were constructed. The recombinant plasmids were amplified in Ecoli. DH5 and then identified by restriction digestion, PCR and sequencing. The recombinant plasmids were transfected into CEN-2 cells. ABCG2 expression was assayed by real-time quantitative PCR and Western blot. The construction of pGC-silencer-U6/Neo/GFP/ABCG2 was succeed. The shRNA plasmids significantly down-regulated the ABCG2 expression in CEN-2 cells, at both mRNA level and protein level. Recombinant plasmid 1 had the strongest effect compared with plasmids 2 and 3 (P < 0.05), with an inhibition ratio of 75% at the mRNA level and 68% at the protein level. pGC-silencer-U6/Neo/GFP/ABCG2 has been successfully constructed and it can down-regulate ABCG2 expression after transfected into CEN-2 cells, which could help further studies of ABCG2 functions CEN-2 cell line and contribute to the NPC gene therapy.

Bacterial mitosis: Partitioning protein ParA oscillates in spiral-shaped structures and positions plasmids at mid-cell

DEFF Research Database (Denmark)

Ebersbach, G.; Gerdes, Kenn

2004-01-01

The par2 locus of Escherichia coli plasmid pB171 encodes oscillating ATPase ParA, DNA binding protein ParB and two cis-acting DNA regions to which ParB binds (parC1 and parC2). Three independent techniques were used to investigate the subcellular localization of plasmids carrying par2. In cells......A-GFP oscillated in spiral-shaped structures. Amino acid substitutions in ParA simultaneously abolished ParA spiral formation, oscillation and either plasmid localization or plasmid separation at mid-cell. Therefore, our results suggest that ParA spirals position plasmids at the middle of the bacterial nucleoid...

Antimicrobial activity of some of the south-Indian spices against serotypes of Escherichia coli, Salmonella, Listeria monocytogenes and Aeromonas hydrophila Atividade antimicrobiana de condimentos do sul da India sobre Escherichia coli, Salmonella, Listeria monocytogenes e Aeromonas hydrophila

Directory of Open Access Journals (Sweden)

M.N. Indu

2006-06-01

Full Text Available Antibacterial activity of extracts of Allium sativum (garlic, Myristica fragrans (nutmeg, Zingiber officinale (ginger, Allium cepa (onion and Piper nigrum (pepper has been evaluated against 20 different serogroups of Escherichia coli, 8 serotypes of Salmonella, Listeria monocytogenes and Aeromonas hydrophila. Garlic extract showed excellent antibacterial activity against all the test organisms, except L. monocytogenes. Nutmeg showed good anti-listerial activity, although activity against E. coli and Salmonella were serotype dependent. Both garlic and nutmeg extracts were effective against A. hydrophila. Extracts of ginger showed inhibitory activity against two serogroups of E. coli: as O8 (enterotoxigenic E. coli and O88 only. Extracts of onion and pepper did not show any antibacterial activity against the test organisms.Avaliou-se a atividade antimicrobiana de extratos de alho (Allium sativum, noz-moscada (Mysritica frangrans, gengibre (Zingiber officinale cebola (Allium cepa e pimenta do reino (Piper nigrum sobre 20 sorotipos de Escherichia coli, 8 sorotipos de Salmonella, Listeria monocytogenes e Aeromonas hydrophila. O alho apresentou atividade antimicrobiana excelente sobre todos os microrganismos testados, excepto L. monocytogenes. A noz-moscada apresentou boa atividade antilisteria, emboara atividade sobre E. coli e Salmonella tenha sido sorotipo-dependente. Tanto alho como noz-moscada foram eficientes contra A. hydrophila. O extrato de gengibre apresentou atividade inibitória sobre dois sorotipos de E. coli: 08 (enterotoxigenico e 088. Os extratos de cebola e pimenta do reino não apresentaram nenhuma atividade contra os microrganismos testados.

Plasmid Complement of Lactococcus lactis NCDO712 Reveals a Novel Pilus Gene Cluster.

Science.gov (United States)

Tarazanova, Mariya; Beerthuyzen, Marke; Siezen, Roland; Fernandez-Gutierrez, Marcela M; de Jong, Anne; van der Meulen, Sjoerd; Kok, Jan; Bachmann, Herwig

2016-01-01

Lactococcus lactis MG1363 is an important gram-positive model organism. It is a plasmid-free and phage-cured derivative of strain NCDO712. Plasmid-cured strains facilitate studies on molecular biological aspects, but many properties which make L. lactis an important organism in the dairy industry are plasmid encoded. We sequenced the total DNA of strain NCDO712 and, contrary to earlier reports, revealed that the strain carries 6 rather than 5 plasmids. A new 50-kb plasmid, designated pNZ712, encodes functional nisin immunity (nisCIP) and copper resistance (lcoRSABC). The copper resistance could be used as a marker for the conjugation of pNZ712 to L. lactis MG1614. A genome comparison with the plasmid cured daughter strain MG1363 showed that the number of single nucleotide polymorphisms that accumulated in the laboratory since the strains diverted more than 30 years ago is limited to 11 of which only 5 lead to amino acid changes. The 16-kb plasmid pSH74 was found to contain a novel 8-kb pilus gene cluster spaCB-spaA-srtC1-srtC2, which is predicted to encode a pilin tip protein SpaC, a pilus basal subunit SpaB, and a pilus backbone protein SpaA. The sortases SrtC1/SrtC2 are most likely involved in pilus polymerization while the chromosomally encoded SrtA could act to anchor the pilus to peptidoglycan in the cell wall. Overexpression of the pilus gene cluster from a multi-copy plasmid in L. lactis MG1363 resulted in cell chaining, aggregation, rapid sedimentation and increased conjugation efficiency of the cells. Electron microscopy showed that the over-expression of the pilus gene cluster leads to appendices on the cell surfaces. A deletion of the gene encoding the putative basal protein spaB, by truncating spaCB, led to more pilus-like structures on the cell surface, but cell aggregation and cell chaining were no longer observed. This is consistent with the prediction that spaB is involved in the anchoring of the pili to the cell.

Characterization and plasmid elimination of NDM-1-producing Acinetobacter calcoaceticus from China.

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Yang Sun

Full Text Available The presence of multidrug-resistant bacterial pathogens in the environment poses a serious threat to public health. The opportunistic Acinetobacter spp. are among the most prevalent causes of nosocomial infections. Here, we performed complete genome sequencing of the Acinetobacter calcoaceticus strain XM1570, which was originally cultivated from the sputum of a patient diagnosed with pneumonia in Xiamen in 2010. We identified carbapenem resistance associated gene bla(NDM-1 located on a 47.3-kb plasmid. Three methods--natural reproduction, sodium dodecyl sulfate treatment and nalidixic acid treatment--were used to eliminate the bla(NDM-1-encoding plasmid, which achieved elimination rates of 3.32% (10/301, 83.78% (278/332, and 84.17% (298/354, respectively. Plasmid elimination dramatically increased antibiotic sensitivity, reducing the minimum bacteriostatic concentration of meropenem from 256 µg/ml in the clinical strain to 0.125 µg/ml in the plasmid-eliminated strain. Conjugation transfer assays showed that the bla(NDM-1-containing plasmid could be transferred into Escherichia coli DH5α:pBR322 in vitro as well as in vivo in mice. The bla(NDM-1 genetic environment was in accordance with that of other bla(NDM-1 genes identified from India, Japan, and Hong-Kong. The multilocus sequence type of the isolate was identified as ST-70. Two novel genes encoding intrinsic OXA and ADC were identified and named as OXA-417 and ADC-72. The finding of bla(NDM-1 in species like A. calcoaceticus demonstrates the wide spread of this gene in gram-negative bacteria which is possible by conjugative plasmid transfer. The results of this study may help in the development of a treatment strategy for controlling NDM-1 bacterial infection and transmission.

Identification of dfrA14 in two distinct plasmids conferring trimethoprim resistance in Actinobacillus pleuropneumoniae.

Science.gov (United States)

Bossé, Janine T; Li, Yanwen; Walker, Stephanie; Atherton, Tom; Fernandez Crespo, Roberto; Williamson, Susanna M; Rogers, Jon; Chaudhuri, Roy R; Weinert, Lucy A; Oshota, Olusegun; Holden, Matt T G; Maskell, Duncan J; Tucker, Alexander W; Wren, Brendan W; Rycroft, Andrew N; Langford, Paul R

2015-08-01

The objective of this study was to determine the distribution and genetic basis of trimethoprim resistance in Actinobacillus pleuropneumoniae isolates from pigs in England. Clinical isolates collected between 1998 and 2011 were tested for resistance to trimethoprim and sulphonamide. The genetic basis of trimethoprim resistance was determined by shotgun WGS analysis and the subsequent isolation and sequencing of plasmids. A total of 16 (out of 106) A. pleuropneumoniae isolates were resistant to both trimethoprim (MIC >32 mg/L) and sulfisoxazole (MIC ≥256 mg/L), and a further 32 were resistant only to sulfisoxazole (MIC ≥256 mg/L). Genome sequence data for the trimethoprim-resistant isolates revealed the presence of the dfrA14 dihydrofolate reductase gene. The distribution of plasmid sequences in multiple contigs suggested the presence of two distinct dfrA14-containing plasmids in different isolates, which was confirmed by plasmid isolation and sequencing. Both plasmids encoded mobilization genes, the sulphonamide resistance gene sul2, as well as dfrA14 inserted into strA, a streptomycin-resistance-associated gene, although the gene order differed between the two plasmids. One of the plasmids further encoded the strB streptomycin-resistance-associated gene. This is the first description of mobilizable plasmids conferring trimethoprim resistance in A. pleuropneumoniae and, to our knowledge, the first report of dfrA14 in any member of the Pasteurellaceae. The identification of dfrA14 conferring trimethoprim resistance in A. pleuropneumoniae isolates will facilitate PCR screens for resistance to this important antimicrobial. © The Author 2015. Published by Oxford University Press on behalf of the British Society for Antimicrobial Chemotherapy.

Aeromonas salmonicida subsp. salmonicida strains isolated from Chinese freshwater fish contain a novel genomic island and possible regional-specific mobile genetic elements profiles

DEFF Research Database (Denmark)

Long, Meng; Nielsen, Tue K; Leisner, Jørgen J

2016-01-01

Two strains of Aeromonas salmonicida, YK and BG, were isolated from largemouth bronze gudgeon and northern whitefish in China, and identified as A. salmonicida subsp. salmonicida based on phylogenetic analysis of vapA and 16S rRNA gene sequences. YK and BG originated from freshwater fish, one...

Protein-Nanocrystal Conjugates Support a Single Filament Polymerization Model in R1 Plasmid Segregation

Energy Technology Data Exchange (ETDEWEB)

Choi, Charina L.; Claridge, Shelley A.; Garner, Ethan C.; Alivisatos, A. Paul; Mullins, R. Dyche

2008-07-15

To ensure inheritance by daughter cells, many low-copy number bacterial plasmids, including the R1 drug-resistance plasmid, encode their own DNA segregation systems. The par operon of plasmid R1 directs construction of a simple spindle structure that converts free energy of polymerization of an actin-like protein, ParM, into work required to move sister plasmids to opposite poles of rod-shaped cells. The structures of individual components have been solved, but little is known about the ultrastructure of the R1 spindle. To determine the number of ParM filaments in a minimal R1 spindle, we used DNA-gold nanocrystal conjugates as mimics of the R1 plasmid. Wefound that each end of a single polar ParM filament binds to a single ParR/parC-gold complex, consistent with the idea that ParM filaments bind in the hollow core of the ParR/parC ring complex. Our results further suggest that multifilament spindles observed in vivo are associated with clusters of plasmidssegregating as a unit.

Effectiveness of ambon banana stem juice as immunostimulatory against Aeromonas hydrophila infections in catfish Clarias gariepinus

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Qorie Astria

2017-07-01

Full Text Available ABSTRACT Outbreaks of infectious diseases due to Aeromonas hydrophila in catfish can cause high death rates (80–100%. Fish disease control can be done using phytopharmaceutical to prevent or treat diseases of fish. One of the phytopharmaceutical that known to prevent the fish diseases is ambon banana stem Musa cavendishii var. dwarf Paxton. This study was conducted to test the effectiveness of catfish immersion using banana stem juice as an immunostimulant against bacterial infections A. hydrophila. The observed parameters were a total performance of production, hematological test, and water quality. Immersion of catfish seeds with stem juice was performed at a concentration of 5 mL/L, 13 mL/L, and 21 mL/L for 30 minutes. Each treatment consisted of three replications. A  total of 15 fishes were immersed in 1.5 L water. At day-9 after immersion, fish was infected by A. hydrophila bacteria at a dose of 104 cfu/mL. The results showed that fish treated with banana stem juice at a concentration of 13 mL/L had the survival rate of 53.33±6.67% which is higher than positive control (33.33±6.67%. Based on hematology observations on the 3rd day post-challenge test (H12 with A. hydrophila, total erythrocytes, hemoglobin, total leukocytes, phagocytic activity, differential leukocyte, and lysozyme activity was highest in treatment13 mL/L. Lower feed conversion ratio (1.08±0.04 were also obtained in treatment 13 mL/L. Thus Immersion of seeds in stem juice can boost the immune system against infections A. hydrophila. Keywords: Aeromonas hydrophila, ambon banana stem juice, soaking, catfish, immune system  ABSTRAK Wabah penyakit akibat infeksi Aeromonas hydrophila pada ikan lele dapat menyebabkan tingkat kematian yang tinggi (80–100%. Penanggulangan penyakit ikan dapat dilakukan menggunakan fitofarmaka untuk mencegah ataupun mengobati penyakit ikan. Salah satu fitofarmaka yang dapat digunakan dalam upaya pencegahan penyakit ikan adalah batang

Protein Structure Initiative Material Repository: an open shared public resource of structural genomics plasmids for the biological community

Science.gov (United States)

Cormier, Catherine Y.; Mohr, Stephanie E.; Zuo, Dongmei; Hu, Yanhui; Rolfs, Andreas; Kramer, Jason; Taycher, Elena; Kelley, Fontina; Fiacco, Michael; Turnbull, Greggory; LaBaer, Joshua

2010-01-01

The Protein Structure Initiative Material Repository (PSI-MR; http://psimr.asu.edu) provides centralized storage and distribution for the protein expression plasmids created by PSI researchers. These plasmids are a resource that allows the research community to dissect the biological function of proteins whose structures have been identified by the PSI. The plasmid annotation, which includes the full length sequence, vector information and associated publications, is stored in a freely available, searchable database called DNASU (http://dnasu.asu.edu). Each PSI plasmid is also linked to a variety of additional resources, which facilitates cross-referencing of a particular plasmid to protein annotations and experimental data. Plasmid samples can be requested directly through the website. We have also developed a novel strategy to avoid the most common concern encountered when distributing plasmids namely, the complexity of material transfer agreement (MTA) processing and the resulting delays this causes. The Expedited Process MTA, in which we created a network of institutions that agree to the terms of transfer in advance of a material request, eliminates these delays. Our hope is that by creating a repository of expression-ready plasmids and expediting the process for receiving these plasmids, we will help accelerate the accessibility and pace of scientific discovery. PMID:19906724

Spontaneous mutability and light-induced mutagenesis in Salmonella typhimurium: effects of an R-plasmid

International Nuclear Information System (INIS)

Valdivia, L.

1979-01-01

The UV-protecting plasmid R46 was transferred by conjugation to a genetically marked mouse-virulent Salmonella typhimurium strain, not derived from LT2; in this host the plasmid conferred UV protection and enhanced UV mutagenesis just as it does in LT2 lines. Tra - derivatives of R46 encountered during transduction retained UV-protecting and mutagenesis-enhancing ability. Stored strains carrying the R46-derived plasmids with strong mutator effect but not UV-protecting had lost most of their original streptomycin resistance but were slightly resistant to spectinomycin; attempts to transfer such plasmids failed. R46 enhanced the weak mutagenic effect of visible light on several his and trp mutants of strain LT2, including some whose frequency of spontaneous reversion was not increased by the plasmid. A mutagenic effect was produced by visible-light irradiation of hisG46(R46), either growing cells or nonmultiplying (histidine-deprived cells at 10 0 C). Presence of catalase or cyanide during irradiation did not prevent mutagenesis, which excludes some hypothetical mechanisms. Visible-light irradiation of hisG46 or hisG46(R46) under strict anaerobiosis had little or no mutagenic effect (controls showed that revertants if produced would have been detected). This is as expected if visible-light irradiation in air causes photodynamic damage to DNA and mutations are produced during error-prone, plasmid-enhanced repair

Isolation of a minireplicon of the plasmid pG6303 of Lactobacillus ...

Indian Academy of Sciences (India)

is a new mode of plasmid replication. [Fan J., Xi X., ... coli using the BioTeKe plasmid extraction kit (BioTeKe, Beijing, China) according .... media and incubated at 37◦C for three days. The methods of ..... Each experiment was repeated five times. Journal of ..... Cold Spring Harbor Laboratory Press, New York, USA. Soler N.

Unraveling the regulatory network of IncA/C plasmid mobilization: When genomic islands hijack conjugative elements.

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Carraro, Nicolas; Matteau, Dominick; Burrus, Vincent; Rodrigue, Sébastien

2015-01-01

Conjugative plasmids of the A/C incompatibility group (IncA/C) have become substantial players in the dissemination of multidrug resistance. These large conjugative plasmids are characterized by their broad host-range, extended spectrum of antimicrobials resistance, and prevalence in enteric bacteria recovered from both environmental and clinical settings. Until recently, relatively little was known about the basic biology of IncA/C plasmids, mostly because of the hindrance of multidrug resistance for molecular biology experiments. To circumvent this issue, we previously developed pVCR94ΔX, a convenient prototype that codes for a reduced set of antibiotic resistances. Using pVCR94ΔX, we then characterized the regulatory pathway governing IncA/C plasmid dissemination. We found that the expression of roughly 2 thirds of the genes encoded by this plasmid, including large operons involved in the conjugation process, depends on an FlhCD-like master activator called AcaCD. Beyond the mobility of IncA/C plasmids, AcaCD was also shown to play a key role in the mobilization of different classes of genomic islands (GIs) identified in various pathogenic bacteria. By doing so, IncA/C plasmids can have a considerable impact on bacterial genomes plasticity and evolution.

Characterization of Plasmid DNA Location within Chitosan/PLGA/pDNA Nanoparticle Complexes Designed for Gene Delivery

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Hali Bordelon

2011-01-01

Full Text Available Poly(D,L-lactide-co-glycolide- (PLGA-chitosan nanoparticles are becoming an increasingly common choice for the delivery of nucleic acids to cells for various genetic manipulation techniques. These particles are biocompatible, with tunable size and surface properties, possessing an overall positive charge that promotes complex formation with negatively charged nucleic acids. This study examines properties of the PLGA-chitosan nanoparticle/plasmid DNA complex after formation. Specifically, the study aims to determine the optimal ratio of plasmid DNA:nanoparticles for nucleic acid delivery purposes and to elucidate the location of the pDNA within these complexes. Such characterization will be necessary for the adoption of these formulations in a clinical setting. The ability of PLGA-chitosan nanoparticles to form complexes with pDNA was evaluated by using the fluorescent intercalating due OliGreen to label free plasmid DNA. By monitoring the fluorescence at different plasmid: nanoparticle ratios, the ideal plasmid:nanoparticle ration for complete complexation of plasmid was determined to be 1:50. Surface-Enhanced Raman Spectroscopy and gel digest studies suggested that even at these optimal complexation ratios, a portion of the plasmid DNA was located on the outer complex surface. This knowledge will facilitate future investigations into the functionality of the system in vitro and in vivo.

STUDY REGARDING EFFICIENCY OF INDUCED GENETIC TRANSFORMATION IN BACILLUS LICHENIFORMIS WITH PLASMID DNA

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T. VINTILĂ

2007-05-01

Full Text Available A strain of Bacillus licheniformis was subject to genetic transformation with plasmid vectors (pLC1 and pNC61, using electroporation technique, protoplast transformation and bivalent cations (CaCl2 mediated transformation. In the case of transformation by electroporation of Bacillus licheniformis B40, the highest number of transformed colonies (3 were obtained only after a 1,79 KV electric shock, for 2,2 milliseconds. Using this transformation technique we have obtained six kanamycin resistant transformants. The frequency of Bacillus licheniformis B40 protoplasts transformation using pLC1 and pNC61 plasmid vectors is approximately 10% (TF = 10%. As a result of pLC1 plasmid integration in Bacillus licheniformis protoplasts, six kanamycin resistant transformants were obtained. The pNC61 plasmid, which confers trimethoprim resistance, does not integrate in receiver cells by protoplast transformation. The direct genetic transformation in the presence of bivalent cations (CaCl2, mediated by pLC1 and pNC61 plasmid vectors, produce a low transformation frequency. Using this technique, we have obtained three trimethoprim resistant colonies and four kanamycin resistant colonies. The chemical way of transformation is the only technique, which realizes the integration of pNC61 in B. licheniformis B40 cells.

Sanitary evaluation of domestic water supply facilities with storage tanks and detection of Aeromonas, enteric and related bacteria in domestic water facilities in Okinawa Prefecture of Japan.

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Miyagi, Kazufumi; Sano, Kouichi; Hirai, Itaru

2017-08-01

To provide for temporary restrictions of the public water supply system, storage tanks are commonly installed in the domestic water systems of houses and apartment buildings in Okinawa Prefecture of Japan. To learn more about the sanitary condition and management of these water supply facilities with storage tanks (hereafter called "storage tank water systems") and the extent of bacterial contamination of water from these facilities, we investigated their usage and the existence of Aeromonas, enteric and related bacteria. Verbal interviews concerning the use and management of the storage tank water systems were carried out in each randomly sampled household. A total of 54 water samples were collected for bacteriological and physicochemical examinations. Conventional methods were used for total viable count, fecal coliforms, identification of bacteria such as Aeromonas, Enterobacteriaceae and non-fermentative Gram-negative rods (NF-GNR), and measurement of residual chlorine. On Aeromonas species, tests for putative virulence factor and an identification using 16S rRNA and rpoB genes were also performed. Water from the water storage systems was reported to be consumed directly without boiling in 22 of the 54 houses (40.7%). 31 of the sampled houses had installed water storage tanks of more than 1 cubic meter (m 3 ) per inhabitant, and in 21 of the sampled houses, the tank had never been cleaned. In all samples, the total viable count and fecal coliforms did not exceed quality levels prescribed by Japanese waterworks law. Although the quantity of bacteria detected was not high, 23 NF-GNR, 14 Enterobacteriaceae and 5 Aeromonas were isolated in 42.6%, 7.4% and 3.7% of samples respectively. One isolated A. hydrophila and four A. caviae possessed various putative virulence factors, especially A. hydrophila which had diverse putative pathogenic genes such as aer, hlyA, act, alt, ast, ser, and dam. Many bacteria were isolated when the concentration of residual chlorine

Dynamics in copy numbers of five plasmids of a dairy Lactococcus lactis in dairy-related conditions including near-zero growth rates.

Science.gov (United States)

van Mastrigt, Oscar; Lommers, Marcel M A N; de Vries, Yorick C; Abee, Tjakko; Smid, Eddy J

2018-03-23

Lactic acid bacteria can carry multiple plasmids affecting their performance in dairy fermentations. The expression of plasmid-encoded genes and the activity of the corresponding proteins is severely affected by changes in the number of plasmid copies. We studied the impact of growth rate on dynamics of plasmid copy numbers at high growth rates in chemostat cultures and down to near-zero growth rates in retentostat cultures. Five plasmids of the dairy strain Lactococcus lactis FM03-V1 were selected which varied in size (3 to 39 kb), in replication mechanism (theta or rolling-circle) and in putative (dairy-associated) functions. Copy numbers ranged from 1.5 to 40.5 and the copy number of theta-type replicating plasmids were negatively correlated to the plasmid size. Despite the extremely wide range of growth rates (0.0003 h -1 to 0.6 h -1 ), copy numbers of the five plasmids were stable and only slightly increased at near-zero growth rates showing that the plasmid replication rate was strictly controlled. One low-copy number plasmid, carrying a large exopolysaccharide gene cluster, was segregationally unstable during retentostat cultivations reflected in complete loss of the plasmid in one of the retentostat cultures. The copy number of the five plasmids was also hardly affected by varying the pH value, nutrient limitation or presence of citrate (maximum 2.2-fold) signifying the stability in copy number of the plasmids. Importance Lactococcus lactis is extensively used in starter cultures for dairy fermentations. Important traits for growth and survival of L. lactis in dairy fermentations are encoded by genes located on plasmids, such as genes involved in lactose and citrate metabolism, protein degradation and oligopeptide uptake and bacteriophage resistance. Because the number of plasmid copies could affect the expression of plasmid-encoded genes, it is important to know the factors that influence the plasmid copy numbers. We monitored plasmid copy numbers of L

Plasmid transfer by conjugation in Xylella fastidiosa.

Science.gov (United States)

Recombination and horizontal gene transfer have been implicated in the adaption of Xylella fastidiosa (Xf) to infect a wide variety of different plant species. There is evidence that certain strains of Xf carry native plasmids equipped with transfer and mobilization genes, suggesting conjugation as ...

Resveratrol production in bioreactor: Assessment of cell physiological states and plasmid segregational stability

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Margarida S. Afonso

2015-03-01

Full Text Available Resveratrol is a plant secondary metabolite commonly found in peanuts and grapevines with significant health benefits. Recombinant organisms can produce large amounts of resveratrol and, in this work, Escherichia coli BW27784 was used to produce resveratrol in bioreactors while monitoring cell physiology and plasmid stability through flow cytometry and real-time qPCR, respectively. Initially, the influence of culture conditions and precursor addition was evaluated in screening assays and the data gathered was used to perform the bioreactor assays, allowing the production of 160 μg/mL of resveratrol. Cellular physiology and plasmid instability affected the final resveratrol production, with lower viability and plasmid copy numbers associated with lower yields. In sum, this study describes new tools to monitor the bioprocess, evaluating the effect of culture conditions, and its correlation with cell physiology and plasmid segregational stability, in order to define a viable and scalable bioprocess to fulfill the need for larger quantities of resveratrol.

Identification of a Novel Conjugative Plasmid in Mycobacteria That Requires Both Type IV and Type VII Secretion

KAUST Repository

Ummels, R.; Abdallah, A. M.; Kuiper, V.; Aajoud, A.; Sparrius, M.; Naeem, R.; Spaink, H. P.; van Soolingen, D.; Pain, Arnab; Bitter, W.

2014-01-01

Conjugative plasmids play an important role in horizontal gene transfer between different bacteria and, as such, in their adaptation and evolution. This effect is most obvious in the spread of antibiotic resistance genes. Thus far, conjugation of natural plasmids has been described only rarely for mycobacterial species. In fact, it is generally accepted that M. tuberculosis does not show any recent sign of horizontal gene transfer. In this study, we describe the identification of a new widespread conjugative plasmid that can also be efficiently transferred to M. tuberculosis. This plasmid therefore poses both a threat and an opportunity. The threat is that, through the acquisition of antibiotic resistance markers, this plasmid could start a rapid spread of antibiotic resistance genes between pathogenic mycobacteria. The opportunity is that we could use this plasmid to generate new tools for the efficient introduction of foreign DNA in slow-growing mycobacteria.

Co-evolution of genomes and plasmids within Chlamydia trachomatis and the emergence in Sweden of a new variant strain

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Skilton Rachel J

2009-05-01

Full Text Available Abstract Background Chlamydia trachomatis is the most common cause of sexually transmitted infections globally and the leading cause of preventable blindness in the developing world. There are two biovariants of C. trachomatis: 'trachoma', causing ocular and genital tract infections, and the invasive 'lymphogranuloma venereum' strains. Recently, a new variant of the genital tract C. trachomatis emerged in Sweden. This variant escaped routine diagnostic tests because it carries a plasmid with a deletion. Failure to detect this strain has meant it has spread rapidly across the country provoking a worldwide alert. In addition to being a key diagnostic target, the plasmid has been linked to chlamydial virulence. Analysis of chlamydial plasmids and their cognate chromosomes was undertaken to provide insights into the evolutionary relationship between chromosome and plasmid. This is essential knowledge if the plasmid is to be continued to be relied on as a key diagnostic marker, and for an understanding of the evolution of Chlamydia trachomatis. Results The genomes of two new C. trachomatis strains were sequenced, together with plasmids from six C. trachomatis isolates, including the new variant strain from Sweden. The plasmid from the new Swedish variant has a 377 bp deletion in the first predicted coding sequence, abolishing the site used for PCR detection, resulting in negative diagnosis. In addition, the variant plasmid has a 44 bp duplication downstream of the deletion. The region containing the second predicted coding sequence is the most highly conserved region of the plasmids investigated. Phylogenetic analysis of the plasmids and chromosomes are fully congruent. Moreover this analysis also shows that ocular and genital strains diverged from a common C. trachomatis progenitor. Conclusion The evolutionary pathways of the chlamydial genome and plasmid imply that inheritance of the plasmid is tightly linked with its cognate chromosome. These data

Development and Host Compatibility of Plasmids for Two Important Ruminant Pathogens, Mycoplasma bovis and Mycoplasma agalactiae

Science.gov (United States)

Sharma, Shukriti; Citti, Chistine; Sagné, Eveline; Marenda, Marc S.

2015-01-01

Mycoplasma bovis is a cause of pneumonia, mastitis, arthritis and otitis media in cattle throughout the world. However, despite its clinical significance, there is a paucity of tools to genetically manipulate it, impeding our capacity to further explore the molecular basis of its virulence. To address this limitation, we developed a series of homologous and heterologous replicable plasmids from M. bovis and M. agalactiae. The shortest replicable oriC plasmid based on the region downstream of dnaA in M. bovis was 247 bp and contained two DnaA boxes, while oriC plasmids based on the region downstream of dnaA in M. agalactiae strains 5632 and PG2 were 219 bp and 217 bp in length, respectively, and contained only a single DnaA box. The efficiency of transformation in M. bovis and M. agalactiae was inversely correlated with the size of the oriC region in the construct, and, in general, homologous oriC plasmids had a higher transformation efficiency than heterologous oriC plasmids. The larger pWholeoriC45 and pMM21-7 plasmids integrated into the genomic oriC region of M. bovis, while the smaller oriC plasmids remained extrachromosomal for up to 20 serial passages in selective media. Although specific gene disruptions were not be achieved in M. bovis in this study, the oriC plasmids developed here could still be useful as tools in complementation studies and for expression of exogenous genes in both M. bovis and M. agalactiae. PMID:25746296

Development and host compatibility of plasmids for two important ruminant pathogens, Mycoplasma bovis and Mycoplasma agalactiae.

Directory of Open Access Journals (Sweden)

Shukriti Sharma

Full Text Available Mycoplasma bovis is a cause of pneumonia, mastitis, arthritis and otitis media in cattle throughout the world. However, despite its clinical significance, there is a paucity of tools to genetically manipulate it, impeding our capacity to further explore the molecular basis of its virulence. To address this limitation, we developed a series of homologous and heterologous replicable plasmids from M. bovis and M. agalactiae. The shortest replicable oriC plasmid based on the region downstream of dnaA in M. bovis was 247 bp and contained two DnaA boxes, while oriC plasmids based on the region downstream of dnaA in M. agalactiae strains 5632 and PG2 were 219 bp and 217 bp in length, respectively, and contained only a single DnaA box. The efficiency of transformation in M. bovis and M. agalactiae was inversely correlated with the size of the oriC region in the construct, and, in general, homologous oriC plasmids had a higher transformation efficiency than heterologous oriC plasmids. The larger pWholeoriC45 and pMM21-7 plasmids integrated into the genomic oriC region of M. bovis, while the smaller oriC plasmids remained extrachromosomal for up to 20 serial passages in selective media. Although specific gene disruptions were not be achieved in M. bovis in this study, the oriC plasmids developed here could still be useful as tools in complementation studies and for expression of exogenous genes in both M. bovis and M. agalactiae.

Plasmid Vectors for Xylella fastidiosa Utilizing a Toxin-Antitoxin System for Stability in the Absence of Antibiotic Selection.

Science.gov (United States)

Burbank, Lindsey P; Stenger, Drake C

2016-08-01

The phytopathogen Xylella fastidiosa causes disease in a variety of important crop and landscape plants. Functional genetic studies have led to a broader understanding of virulence mechanisms used by this pathogen in the grapevine host. Plasmid shuttle vectors are important tools in studies of bacterial genetics but there are only a limited number of plasmid vectors available that replicate in X. fastidiosa, and even fewer that are retained without antibiotic selection. Two plasmids are described here that show stable replication in X. fastidiosa and are effective for gene complementation both in vitro and in planta. Plasmid maintenance is facilitated by incorporation of the PemI/PemK plasmid addiction system, consisting of PemK, an endoribonuclease toxin, and its cognate antitoxin, PemI. Vector pXf20pemIK utilizes a native X. fastidiosa replication origin as well as a high-copy-number pUC origin for propagation in Escherichia coli cloning strains. Broad-host-range vector pBBR5pemIK is a medium- to low-copy-number plasmid based on the pBBR1 backbone. Both plasmids are maintained for extended periods of time in the absence of antibiotic selection, as well as up to 14 weeks in grapevine, without affecting bacterial fitness. These plasmids present an alternative to traditional complementation and expression vectors which rely on antibiotic selection for plasmid retention.

Therapeutic effects of marshmallow (Althaea officinalis L.) extract on plasma biochemical parameters of common carp infected with Aeromonas hydrophila

OpenAIRE

Banaee, Mahdi; Soleimany, Vahid; Nematdoost Haghi, Behzad

2017-01-01

This study evaluated preclinical and clinical safety of marshmallow (Althaea officinalis L.) extract as a naturopathic medicine in common carp deliberately infected with Aeromonas hydrophila. The fish were fed 0 (control), 2.50, 5.00 and 10.00 g of marshmallow extract for 60 days in a preclinical experiment and then, challenged with A. hydrophila for a 10-day experiment. Significant increases were observed in aspartate aminotransferase (AST), lactate dehydrogenase (LDH), alkaline phosphatase ...

VAKSINASI IKAN TILAPIA (Oreochromis niloticus MENGGUNAKAN VAKSIN MONOVALEN DAN BIVALEN UNTUK PENCEGAHAN PENYAKIT MOTILE AEROMONAS SEPTICEMIA DAN STREPTOCOCCOSIS

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Desy Sugiani

2013-08-01

Full Text Available Peningkatan respon antibodi pascavaksinasi dengan antigen tunggal dan campuran dari bakterin Aeromonas hydrophila and Streptococcus agalactiae diharapkan dapat meningkatkan daya tahan ikan tilapia (Oreochromis niloticus terhadap penyakit Motile Aeromonas Septicemia/MAS dan Streptococcosis. Sediaan vaksin disiapkan dengan metode pembuatan dan formula yang berbeda, proses inaktifasi dilakukan dengan menambahkan 3% Neutral Buffer Formalin (NBF 10% pada biakan bakteri dalam media tumbuh BHI dan TSB. Vaksinasi diberikan melalui injeksi intraperitoneal dengan sediaan vaksin monovalen A. hydrophila, monovalen S. agalactiae, dan bivalen A. hydrophila + S. agalactiae (Sel utuh, produk ektraselular/ECP, crude supernatan, campuran sel utuh + ECP, dan broth. Uji tantang dilakukan menggunakan dosis LD50 infeksi tunggal maupun ko-infeksi dari bakteri A. hydrophila dan S. agalactiae. Efektivitas dan keampuhan vaksin tersebut dihitung berdasarkan nilai RPS (Relative Percent Survival dan hasil respon hematologi. Titer antibodi dapat terdeteksi setelah satu minggu pemeliharaan pasca vaksinasi. Nilai titer antar perlakuan vaksin bivalen berbeda nyata (P<0.05 dengan vaksin monovalen dan kontrol. Nilai RPS vaksin bivalen (campuran sel utuh + ECP mencapai 100 untuk uji tantang dengan A. hydrophila dan 56,7 pada uji tantang ko-infeksi. Vaksin monovalen A. hydrophila maupun S. agalactiae hanya mampu memproteksi terhadap bakteri homolog, tidak terjadi proteksi silang di antara keduanya.

UJI AKTIVITAS ANTIBAKTERI EKSTRAK RUMPUT LAUT Kappaphycus alvarezii DAN Eucheuma denticullatum TERHADAP BAKTERI Aeromonas hydrophila DAN Vibrio harveyii

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Dwi Budi Wiyanto

2010-04-01

Full Text Available Penelitian tentang Uji Aktivitas Antibakteri Ekstrak Rumput Laut Kappaphycus alvarezii dan Eucheuma denticullatum Terhadap Bakteri Aeromonas hydrophila dan Vibrio harveyii dilakukan, mengingat banyak dijumpai  penyakit pada usaha budidaya ikan dan udang, terutama bakteri Aeromonas hydrophila dan Vibrio harveyii. Penelitian ini bertujuan untuk mengetahui efektifitas senyawa bioaktif rumput laut K. alvarezii dan E. denticullatum yang diekstrak menggunakan pelarut metanol dan etanol sebagai antibakteri terhadap A. hydrophila dan V. harveyii.  Penelitian dilakukan sebanyak dua tahap, yaitu: (1 Uji aktivitas antibakteri ekstrak rumput laut; dan (2 Analisa senyawa bioaktif yang terdapat pada ekstrak rumput laut, dimana masing-masing tahapan dianalisis menggunakan rancangan acak lengkap faktorial. Hasil penelitian menunjukkan, dua jenis ekstrak rumput laut dengan pelarut metanol dan etanol, mempunyai daya antibakteri terhadap A. hydrophila dan V. harveyii. Ekstrak E. denticullatum dengan pelarut metanol memiliki daya hambat lebih luas dibanding ekstrak K. alvarezii dengan pelarut metanol terhadap A. hydrophila (19.43±0,55 mm. Ekstrak E. denticullatum dengan pelarut metanol memiliki daya hambat lebih luas dibanding ekastrak K. alvarezii dengan pelarut metanol terhadap V. harveyii (19.85±0,23 mm. Asam heksadekanoat merupakan senyawa paling dominan dijumpai pada ekstrak rumput laut K. alvarezii, dan E. denticullatum yang diekstrak menggunakan pelarut metanol. Kata Kunci : Aktivitas Antibakteri, Rumput laut K. alvarezii dan E. denticullatum,  Bakteri A.  hydrophila dan V. harveyii. 

A genetic study of a Staphylococus aureus plasmid involving cure and transference

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Ana Lúcia Costa Darini

Full Text Available High frequency transfer and elimination of drug resistance may indicate an extrachromosomal inheritance of genetic determinants. This study shows the cure and transfer of a small plasmid and tetracycline resistance in Staphylococcus aureus 1030 (55TetR strains. Several methods are available for plasmid elimination. We used ethidium bromide, an agent that binds to DNA, and thus inhibits DNA polymerase. This caused a high frequency of loss of the small plasmid and resistance to tetracycline. Transfer of tetracycline resistance was done in a mixed culture at a frequency of 10-6. This type of study is very important to physicians and epidemiology investigators and provides better knowledge on antibiotic-resistance mechanisms that may occur in vivo in a hospital environment.

Regular cellular distribution of plasmids by oscillating and filament-forming ParA ATPase of plasmid pB171

DEFF Research Database (Denmark)

Ebersbach, Gitte; Ringgaard, Simon; Møller-Jensen, Jakob

2006-01-01

with each other in a bacterial two-hybrid assay but do not interact with FtsZ, eight other essential cell division proteins or MreB actin. Based on these observations, we propose a simple model for how oscillating ParA filaments can mediate regular cellular distribution of plasmids. The model functions...

Sequencing of IncX-plasmids suggests ubiquity of mobile forms of a biofilm-promoting gene cassette recruited from Klebsiella pneumoniae.

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Mette Burmølle

Full Text Available Plasmids are a highly effective means with which genetic traits that influence human health, such as virulence and antibiotic resistance, are disseminated through bacterial populations. The IncX-family is a hitherto sparsely populated group of plasmids that are able to thrive within Enterobacteriaceae. In this study, a replicon-centric screening method was used to locate strains from wastewater sludge containing plasmids belonging to the IncX-family. A transposon aided plasmid capture method was then employed to transport IncX-plasmids from their original hosts (and co-hosted plasmids into a laboratory strain (Escherichia coli Genehogs® for further study. The nucleotide sequences of the three newly isolated IncX-plasmids (pLN126_33, pMO17_54, pMO440_54 and the hitherto un-sequenced type-plasmid R485 revealed a remarkable occurrence of whole or partial gene cassettes that promote biofilm-formation in Klebsiella pneumonia or E. coli, in all four instances. Two of the plasmids (R485 and pLN126_33 were shown to directly induce biofilm formation in a crystal violet retention assay in E. coli. Sequence comparison revealed that all plasmid-borne forms of the type 3 fimbriae encoding gene cassette mrkABCDF were variations of a composite transposon Tn6011 first described in the E. coli IncX plasmid pOLA52. In conclusion, IncX-plasmids isolated from Enterobacteriaceae over almost 40 years and on three different continents have all been shown to carry a type 3 fimbriae gene cassette mrkABCDF stemming from pathogenic K. pneumoniae. Apart from contributing general knowledge about IncX-plasmids, this study also suggests an apparent ubiquity of a mobile form of an important virulence factor and is an illuminating example of the recruitment, evolution and dissemination of genetic traits through plasmid-mediated horizontal gene transfer.

Sequencing of IncX-plasmids suggests ubiquity of mobile forms of a biofilm-promoting gene cassette recruited from Klebsiella pneumoniae.

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Burmølle, Mette; Norman, Anders; Sørensen, Søren J; Hansen, Lars Hestbjerg

2012-01-01

Plasmids are a highly effective means with which genetic traits that influence human health, such as virulence and antibiotic resistance, are disseminated through bacterial populations. The IncX-family is a hitherto sparsely populated group of plasmids that are able to thrive within Enterobacteriaceae. In this study, a replicon-centric screening method was used to locate strains from wastewater sludge containing plasmids belonging to the IncX-family. A transposon aided plasmid capture method was then employed to transport IncX-plasmids from their original hosts (and co-hosted plasmids) into a laboratory strain (Escherichia coli Genehogs®) for further study. The nucleotide sequences of the three newly isolated IncX-plasmids (pLN126_33, pMO17_54, pMO440_54) and the hitherto un-sequenced type-plasmid R485 revealed a remarkable occurrence of whole or partial gene cassettes that promote biofilm-formation in Klebsiella pneumonia or E. coli, in all four instances. Two of the plasmids (R485 and pLN126_33) were shown to directly induce biofilm formation in a crystal violet retention assay in E. coli. Sequence comparison revealed that all plasmid-borne forms of the type 3 fimbriae encoding gene cassette mrkABCDF were variations of a composite transposon Tn6011 first described in the E. coli IncX plasmid pOLA52. In conclusion, IncX-plasmids isolated from Enterobacteriaceae over almost 40 years and on three different continents have all been shown to carry a type 3 fimbriae gene cassette mrkABCDF stemming from pathogenic K. pneumoniae. Apart from contributing general knowledge about IncX-plasmids, this study also suggests an apparent ubiquity of a mobile form of an important virulence factor and is an illuminating example of the recruitment, evolution and dissemination of genetic traits through plasmid-mediated horizontal gene transfer.

Ordering the mob: Insights into replicon and MOB typing schemes from analysis of a curated dataset of publicly available plasmids.

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Orlek, Alex; Phan, Hang; Sheppard, Anna E; Doumith, Michel; Ellington, Matthew; Peto, Tim; Crook, Derrick; Walker, A Sarah; Woodford, Neil; Anjum, Muna F; Stoesser, Nicole

2017-05-01

Plasmid typing can provide insights into the epidemiology and transmission of plasmid-mediated antibiotic resistance. The principal plasmid typing schemes are replicon typing and MOB typing, which utilize variation in replication loci and relaxase proteins respectively. Previous studies investigating the proportion of plasmids assigned a type by these schemes ('typeability') have yielded conflicting results; moreover, thousands of plasmid sequences have been added to NCBI in recent years, without consistent annotation to indicate which sequences represent complete plasmids. Here, a curated dataset of complete Enterobacteriaceae plasmids from NCBI was compiled, and used to assess the typeability and concordance of in silico replicon and MOB typing schemes. Concordance was assessed at hierarchical replicon type resolutions, from replicon family-level to plasmid multilocus sequence type (pMLST)-level, where available. We found that 85% and 65% of the curated plasmids could be replicon and MOB typed, respectively. Overall, plasmid size and the number of resistance genes were significant independent predictors of replicon and MOB typing success. We found some degree of non-concordance between replicon families and MOB types, which was only partly resolved when partitioning plasmids into finer-resolution groups (replicon and pMLST types). In some cases, non-concordance was attributed to ambiguous boundaries between MOBP and MOBQ types; in other cases, backbone mosaicism was considered a more plausible explanation. β-lactamase resistance genes tended not to show fidelity to a particular plasmid type, though some previously reported associations were supported. Overall, replicon and MOB typing schemes are likely to continue playing an important role in plasmid analysis, but their performance is constrained by the diverse and dynamic nature of plasmid genomes. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

Comparative assessment of plasmid DNA delivery by encapsulation ...

African Journals Online (AJOL)

Tropical Journal of Pharmaceutical Research January 2018; 17 (1): 1-10 ... Purpose: To compare the gene delivery effectiveness of plasmid DNA (pDNA) ..... Intramuscular delivery of DNA ... copolymeric system for gene delivery in complete.

Protection from ischemic heart injury by a vigilant heme oxygenase-1 plasmid system.

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Tang, Yao Liang; Tang, Yi; Zhang, Y Clare; Qian, Keping; Shen, Leping; Phillips, M Ian

2004-04-01

Although human heme oxygenase-1 (hHO-1) could provide a useful approach for cellular protection in the ischemic heart, constitutive overexpression of hHO-1 may lead to unwanted side effects. To avoid this, we designed a hypoxia-regulated hHO-1 gene therapy system that can be switched on and off. This vigilant plasmid system is composed of myosin light chain-2v promoter and a gene switch that is based on an oxygen-dependent degradation domain from the hypoxia inducible factor-1-alpha. The vector can sense ischemia and switch on the hHO-1 gene system, specifically in the heart. In an in vivo experiment, the vigilant hHO-1 plasmid or saline was injected intramyocardially into myocardial infarction mice or sham operation mice. After gene transfer, expression of hHO-1 was only detected in the ischemic heart treated with vigilant hHO-1 plasmids. Masson trichrome staining showed significantly fewer fibrotic areas in vigilant hHO-1 plasmids-treated mice compared with saline control (43.0%+/-4.8% versus 62.5%+/-3.3%, PhHO-1 expression in peri-infarct border areas, concomitant with higher Bcl-2 levels and lower Bax, Bak, and caspase 3 levels in the ischemic myocardium compared with saline control. By use of a cardiac catheter, heart from vigilant hHO-1 plasmids-treated mice showed improved recovery of contractile and diastolic performance after myocardial infarction compared with saline control. This study documents the beneficial regulation and therapeutic potential of vigilant plasmid-mediated hHO-1 gene transfer. This novel gene transfer strategy can provide cardiac-specific protection from future repeated bouts of ischemic injury.

Plasmid vectors for Xylella fastidiosa utilizing a toxin-antitoxin system for plasmid stability in the absence of antibiotic selection

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The phytopathogen Xylella fastidiosa causes disease in a variety of important crop and landscape plants. Functional genetic studies have led to a broader understanding of virulence mechanisms used by this pathogen in the grapevine host. Plasmid shuttle vectors are important tools in studies of bacte...

Prevalence and characterization of plasmids carrying sulfonamide resistance genes among Escherichia coli from pigs, pig carcasses and human.

Science.gov (United States)

Wu, Shuyu; Dalsgaard, Anders; Hammerum, Anette M; Porsbo, Lone J; Jensen, Lars B

2010-07-30

Sulfonamide resistance is very common in Escherichia coli. The aim of this study was to characterize plasmids carrying sulfonamide resistance genes (sul1, sul2 and sul3) in E. coli isolated from pigs and humans with a specific objective to assess the genetic diversity of plasmids involved in the mobility of sul genes. A total of 501 E. coli isolates from pig feces, pig carcasses and human stools were tested for their susceptibility to selected antimicrobial. Multiplex PCR was conducted to detect the presence of three sul genes among the sulfonamide-resistant E. coli isolates. Fifty-seven sulfonamide-resistant E. coli were selected based on presence of sul resistance genes and subjected to conjugation and/or transformation experiments. S1 nuclease digestion followed by pulsed-field gel electrophoresis was used to visualize and determine the size of plasmids. Plasmids carrying sul genes were characterized by PCR-based replicon typing to allow a comparison of the types of sul genes, the reservoir and plasmid present. A total of 109/501 isolates exhibited sulfonamide resistance. The relative prevalences of sul genes from the three reservoirs (pigs, pig carcasses and humans) were 65%, 45% and 12% for sul2, sul1, and sul3, respectively. Transfer of resistance through conjugation was observed in 42/57 isolates. Resistances to streptomycin, ampicillin and trimethoprim were co-transferred in most strains. Class 1 integrons were present in 80% of sul1-carrying plasmids and 100% of sul3-carrying plasmids, but only in 5% of sul2-carrying plasmids. The sul plasmids ranged from 33 to 160-kb in size and belonged to nine different incompatibility (Inc) groups: FII, FIB, I1, FIA, B/O, FIC, N, HI1 and X1. IncFII was the dominant type in sul2-carrying plasmids (52%), while IncI1 was the most common type in sul1 and sul3-carrying plasmids (33% and 45%, respectively). Multireplicons were found associated with all three sul genes. Sul genes were distributed widely in E. coli isolated

Prevalence and characterization of plasmids carrying sulfonamide resistance genes among Escherichia coli from pigs, pig carcasses and human

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Hammerum Anette M

2010-07-01

Full Text Available Abstract Background Sulfonamide resistance is very common in Escherichia coli. The aim of this study was to characterize plasmids carrying sulfonamide resistance genes (sul1, sul2 and sul3 in E. coli isolated from pigs and humans with a specific objective to assess the genetic diversity of plasmids involved in the mobility of sul genes. Methods A total of 501 E. coli isolates from pig feces, pig carcasses and human stools were tested for their susceptibility to selected antimicrobial. Multiplex PCR was conducted to detect the presence of three sul genes among the sulfonamide-resistant E. coli isolates. Fifty-seven sulfonamide-resistant E. coli were selected based on presence of sul resistance genes and subjected to conjugation and/or transformation experiments. S1 nuclease digestion followed by pulsed-field gel electrophoresis was used to visualize and determine the size of plasmids. Plasmids carrying sul genes were characterized by PCR-based replicon typing to allow a comparison of the types of sul genes, the reservoir and plasmid present. Results A total of 109/501 isolates exhibited sulfonamide resistance. The relative prevalences of sul genes from the three reservoirs (pigs, pig carcasses and humans were 65%, 45% and 12% for sul2, sul1, and sul3, respectively. Transfer of resistance through conjugation was observed in 42/57 isolates. Resistances to streptomycin, ampicillin and trimethoprim were co-transferred in most strains. Class 1 integrons were present in 80% of sul1-carrying plasmids and 100% of sul3-carrying plasmids, but only in 5% of sul2-carrying plasmids. The sul plasmids ranged from 33 to 160-kb in size and belonged to nine different incompatibility (Inc groups: FII, FIB, I1, FIA, B/O, FIC, N, HI1 and X1. IncFII was the dominant type in sul2-carrying plasmids (52%, while IncI1 was the most common type in sul1 and sul3-carrying plasmids (33% and 45%, respectively. Multireplicons were found associated with all three sul genes

Optimization of plasmid electrotransformation into Escherichia coli ...

African Journals Online (AJOL)

In order to improve electroporation, optical density of bacteria, recovery time and electrical parameter (field strength and capacitance) were optimized using the Taguchi statistical method. ANOVA of obtained data indicated that the optimal conditions of electrotransformation of pET-28a (+) plasmid into Escherichia coli ...

Antimicrobial resistance patterns and plasmid profiles of ...

African Journals Online (AJOL)

Objectives: To determine the frequency of resistance of Staphylococcus aureus to various antimicrobial agents, and the relationship between antimicrobial resistance of the isolates and carriage of plasmids. Design: A random sampling of milk and meat samples was carried out. Setting: Milk was collected from various dairy ...

Phytochemical analysis of Binahong (Anredera Cordifolia) leaves extract to inhibit In Vitro growth of Aeromonas Hydrophila

Science.gov (United States)

Basyuni, Mohammad; Ginting, Prita Yulianti Anasta Br; Lesmana, Indra

2017-11-01

Binahong (Anredera cordifolia) is one of the medicinal plants commonly used to treat the disease of living organisms. The secondary metabolite of A. cordifolia leaves has been shown antibacterial activity. This study aimed to investigate the secondary metabolite of A. cordifolia leaves showing antibacterial and analysis the effectiveness of antibacterial to inhibit the growth of bacteria Aeromonas hydrophila. A paper disc soaked in a solution of A. cordifolia leaves extract was used to test in vitro at a concentration of 0% (w/v), 0.2%, 0.4%, 0.6%, 0.8%, and positive control of antibiotic (oxytetracycline), respectively. The extracts then placed on a tryptone soy agar (TSA) medium containing bacteria A. hydrophila and incubated at 37 °C for 24 hours. In vitro test showed that A. cordifolia leaves extract inhibited the growth of bacteria A. hydrophila with an inhibition area around the paper disc. The inhibition growth of A. hydrophila increased with the increasing of extract concentration. Bacterial growth was inhibited in the diameter zone of A. hydrophila under different levels of the extracts were 0 mm (0 % negative control), 8.4 mm (0.2 %), 9.4 mm (0.4 %), 10.5 mm (0.6 %), 11.9 mm (0.8 %), 27.5 mm (positive control), respectively. Phytochemical screening of A. cordifolia leaves extract indicated that the extracts contained flavonoid, phenol, saponin, alkaloid, triterpenoid, and β-sitosterol. Our in vitro study demonstrated the inhibition growth of A. hydrophila that caused the disease of motile Aeromonas septicemia (MAS).

A degenerate primer MOB typing (DPMT method to classify gamma-proteobacterial plasmids in clinical and environmental settings.

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Andrés Alvarado

Full Text Available Transmissible plasmids are responsible for the spread of genetic determinants, such as antibiotic resistance or virulence traits, causing a large ecological and epidemiological impact. Transmissible plasmids, either conjugative or mobilizable, have in common the presence of a relaxase gene. Relaxases were previously classified in six protein families according to their phylogeny. Degenerate primers hybridizing to coding sequences of conserved amino acid motifs were designed to amplify related relaxase genes from γ-Proteobacterial plasmids. Specificity and sensitivity of a selected set of 19 primer pairs were first tested using a collection of 33 reference relaxases, representing the diversity of γ-Proteobacterial plasmids. The validated set was then applied to the analysis of two plasmid collections obtained from clinical isolates. The relaxase screening method, which we call "Degenerate Primer MOB Typing" or DPMT, detected not only most known Inc/Rep groups, but also a plethora of plasmids not previously assigned to any Inc group or Rep-type.

Protocol for Evaluating the Permissiveness of Bacterial Communities Toward Conjugal Plasmids by Quantification and Isolation of Transconjugants

DEFF Research Database (Denmark)

Klümper, Uli; Dechesne, Arnaud; Smets, Barth F.

2014-01-01

may encode catabolic pathways, virulence factors, and antibiotic or metal resistances, it is of environmental, evolutionary, and medical relevance to track and monitor the fate of plasmids in mixed microbial community. When assessing the short-term and long-term implications of conjugal plasmid...... a gfp-tagged plasmid in a mCherry red fluorescently tagged donor strain repressing gfp expression. We take advantage of fluorescent marker genes to microscopically detect plasmid transfer events and use subsequent high-throughput fluorescence-activated cell sorting (FACS) to isolate...

Survival and evolution of a large multidrug resistance plasmid in new clinical bacterial hosts

DEFF Research Database (Denmark)

Porse, Andreas; Schønning, Kristian; Munck, Christian

2016-01-01

Large conjugative plasmids are important drivers of bacterial evolution and contribute significantly to the dissemination of antibiotic resistance. Although plasmid borne multidrug resistance is recognized as one of the main challenges in modern medicine, the adaptive forces shaping the evolution...

A novel pAA virulence plasmid encoding toxins and two distinct variants of the fimbriae of enteroaggregative Escherichia coli

DEFF Research Database (Denmark)

Jønsson, Rie; Struve, Carsten; Boll, Erik J.

2017-01-01

phylogenetically distinct, strains harboring the major pilin subunits from both AAF/III and AAF/V. Whole-genome and plasmid sequencing revealed that in these six strains the agg3A and agg5A genes were located on a novel pAA plasmid variant. Moreover, the plasmid also encoded several other virulence genes including...... some not previously found on pAA plasmids. Thus, this plasmid endows the host strains with a remarkably high number of EAEC associated virulence genes hereby likely promoting strain pathogenicity....

The sudden dominance of blaCTX-M harbouring plasmids in Shigella spp. Circulating in Southern Vietnam.

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Nhu Thi Khanh Nguyen

2010-06-01

Full Text Available Plasmid mediated antimicrobial resistance in the Enterobacteriaceae is a global problem. The rise of CTX-M class extended spectrum beta lactamases (ESBLs has been well documented in industrialized countries. Vietnam is representative of a typical transitional middle income country where the spectrum of infectious diseases combined with the spread of drug resistance is shifting and bringing new healthcare challenges.We collected hospital admission data from the pediatric population attending the hospital for tropical diseases in Ho Chi Minh City with Shigella infections. Organisms were cultured from all enrolled patients and subjected to antimicrobial susceptibility testing. Those that were ESBL positive were subjected to further investigation. These investigations included PCR amplification for common ESBL genes, plasmid investigation, conjugation, microarray hybridization and DNA sequencing of a bla(CTX-M encoding plasmid.We show that two different bla(CTX-M genes are circulating in this bacterial population in this location. Sequence of one of the ESBL plasmids shows that rather than the gene being integrated into a preexisting MDR plasmid, the bla(CTX-M gene is located on relatively simple conjugative plasmid. The sequenced plasmid (pEG356 carried the bla(CTX-M-24 gene on an ISEcp1 element and demonstrated considerable sequence homology with other IncFI plasmids.The rapid dissemination, spread of antimicrobial resistance and changing population of Shigella spp. concurrent with economic growth are pertinent to many other countries undergoing similar development. Third generation cephalosporins are commonly used empiric antibiotics in Ho Chi Minh City. We recommend that these agents should not be considered for therapy of dysentery in this setting.

CAPRRESI: Chimera Assembly by Plasmid Recovery and Restriction Enzyme Site Insertion.

Science.gov (United States)

Santillán, Orlando; Ramírez-Romero, Miguel A; Dávila, Guillermo

2017-06-25

Here, we present chimera assembly by plasmid recovery and restriction enzyme site insertion (CAPRRESI). CAPRRESI benefits from many strengths of the original plasmid recovery method and introduces restriction enzyme digestion to ease DNA ligation reactions (required for chimera assembly). For this protocol, users clone wildtype genes into the same plasmid (pUC18 or pUC19). After the in silico selection of amino acid sequence regions where chimeras should be assembled, users obtain all the synonym DNA sequences that encode them. Ad hoc Perl scripts enable users to determine all synonym DNA sequences. After this step, another Perl script searches for restriction enzyme sites on all synonym DNA sequences. This in silico analysis is also performed using the ampicillin resistance gene (ampR) found on pUC18/19 plasmids. Users design oligonucleotides inside synonym regions to disrupt wildtype and ampR genes by PCR. After obtaining and purifying complementary DNA fragments, restriction enzyme digestion is accomplished. Chimera assembly is achieved by ligating appropriate complementary DNA fragments. pUC18/19 vectors are selected for CAPRRESI because they offer technical advantages, such as small size (2,686 base pairs), high copy number, advantageous sequencing reaction features, and commercial availability. The usage of restriction enzymes for chimera assembly eliminates the need for DNA polymerases yielding blunt-ended products. CAPRRESI is a fast and low-cost method for fusing protein-coding genes.

The technology of large-scale pharmaceutical plasmid purification ...

African Journals Online (AJOL)

STORAGESEVER

2010-01-04

Jan 4, 2010 ... DNA vaccine, the cost of purification must be decreased. Although commonly .... Three mice were killed every 4 days interval. Tissues of heart, liver, .... Now, methods such as chromatography had good prospects in plasmid ...

Diversity of Clostridium perfringens isolates from various sources and prevalence of conjugative plasmids.

Science.gov (United States)

Park, Miseon; Deck, Joanna; Foley, Steven L; Nayak, Rajesh; Songer, J Glenn; Seibel, Janice R; Khan, Saeed A; Rooney, Alejandro P; Hecht, David W; Rafii, Fatemeh

2016-04-01

Clostridium perfringens is an important pathogen, causing food poisoning and other mild to severe infections in humans and animals. Some strains of C. perfringens contain conjugative plasmids, which may carry antimicrobial resistance and toxin genes. We studied genomic and plasmid diversity of 145 C. perfringens type A strains isolated from soils, foods, chickens, clinical samples, and domestic animals (porcine, bovine and canine), from different geographic areas in the United States between 1994 and 2006, using multiple-locus variable-number tandem repeat analysis (MLVA) and/or pulsed-field gel electrophoresis (PFGE). MLVA detected the genetic diversity in a majority of the isolates. PFGE, using SmaI and KspI, confirmed the MLVA results but also detected differences among the strains that could not be differentiated by MLVA. All of the PFGE profiles of the strains were different, except for a few of the epidemiologically related strains, which were identical. The PFGE profiles of strains isolated from the same domestic animal species were clustered more closely with each other than with other strains. However, a variety of C. perfringens strains with distinct genetic backgrounds were found among the clinical isolates. Variation was also observed in the size and number of plasmids in the strains. Primers for the internal fragment of a conjugative tcpH gene of C. perfringens plasmid pCPF4969 amplified identical size fragments from a majority of strains tested; and this gene hybridized to the various-sized plasmids of these strains. The sequences of the PCR-amplified tcpH genes from 12 strains showed diversity among the tcpH genes. Regardless of the sources of the isolates, the genetic diversity of C. perfringens extended to the plasmids carrying conjugative genes. Published by Elsevier Ltd.

Characterization of replication and conjugation of plasmid pWTY27 from a widely distributed Streptomyces species

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Wang Tao

2012-11-01

Full Text Available Abstract Background Streptomyces species are widely distributed in natural habitats, such as soils, lakes, plants and some extreme environments. Replication loci of several Streptomyces theta-type plasmids have been reported, but are not characterized in details. Conjugation loci of some Streptomyces rolling-circle-type plasmids are identified and mechanism of conjugal transferring are described. Results We report the detection of a widely distributed Streptomyces strain Y27 and its indigenous plasmid pWTY27 from fourteen plants and four soil samples cross China by both culturing and nonculturing methods. The complete nucleotide sequence of pWTY27 consisted of 14,288 bp. A basic locus for plasmid replication comprised repAB genes and an adjacent iteron sequence, to a long inverted-repeat (ca. 105 bp of which the RepA protein bound specifically in vitro, suggesting that RepA may recognize a second structure (e.g. a long stem-loop of the iteron DNA. A plasmid containing the locus propagated in linear mode when the telomeres of a linear plasmid were attached, indicating a bi-directional replication mode for pWTY27. As for rolling-circle plasmids, a single traA gene and a clt sequence (covering 16 bp within traA and its adjacent 159 bp on pWTY27 were required for plasmid transfer. TraA recognized and bound specifically to the two regions of the clt sequence, one containing all the four DC1 of 7 bp (TGACACC and one DC2 (CCCGCCC and most of IC1, and another covering two DC2 and part of IC1, suggesting formation of a high-ordered DNA-protein complex. Conclusions This work (i isolates a widespread Streptomyces strain Y27 and sequences its indigenous theta-type plasmid pWTY27; (ii identifies the replication and conjugation loci of pWTY27 and; (iii characterizes the binding sequences of the RepA and TraA proteins.

Characterization of replication and conjugation of plasmid pWTY27 from a widely distributed Streptomyces species

Science.gov (United States)

2012-01-01

Background Streptomyces species are widely distributed in natural habitats, such as soils, lakes, plants and some extreme environments. Replication loci of several Streptomyces theta-type plasmids have been reported, but are not characterized in details. Conjugation loci of some Streptomyces rolling-circle-type plasmids are identified and mechanism of conjugal transferring are described. Results We report the detection of a widely distributed Streptomyces strain Y27 and its indigenous plasmid pWTY27 from fourteen plants and four soil samples cross China by both culturing and nonculturing methods. The complete nucleotide sequence of pWTY27 consisted of 14,288 bp. A basic locus for plasmid replication comprised repAB genes and an adjacent iteron sequence, to a long inverted-repeat (ca. 105 bp) of which the RepA protein bound specifically in vitro, suggesting that RepA may recognize a second structure (e.g. a long stem-loop) of the iteron DNA. A plasmid containing the locus propagated in linear mode when the telomeres of a linear plasmid were attached, indicating a bi-directional replication mode for pWTY27. As for rolling-circle plasmids, a single traA gene and a clt sequence (covering 16 bp within traA and its adjacent 159 bp) on pWTY27 were required for plasmid transfer. TraA recognized and bound specifically to the two regions of the clt sequence, one containing all the four DC1 of 7 bp (TGACACC) and one DC2 (CCCGCCC) and most of IC1, and another covering two DC2 and part of IC1, suggesting formation of a high-ordered DNA-protein complex. Conclusions This work (i) isolates a widespread Streptomyces strain Y27 and sequences its indigenous theta-type plasmid pWTY27; (ii) identifies the replication and conjugation loci of pWTY27 and; (iii) characterizes the binding sequences of the RepA and TraA proteins. PMID:23134842

Damage of plasmid DNA by high energy ions

International Nuclear Information System (INIS)

Michaelidesova, A.; Pachnerova Brabcova, K.; Davidkova, M.

2018-01-01

The aim of the study was to determine the degree of direct DNA damage by high-energy ions, which are one of the components of cosmic rays, and therefore the knowledge of the biological effects of these ions is key to long-term space missions with human crew. The pBR322 plasmid containing 4361 base pairs was used in this study. The aqueous solution of plasmid pBR322 was transferred on ice to Japan to the Heavy Ion Medical Accelerator in Chiba, the Research Center for Charged Particle Therapy. Just before the experiment, the droplets of solution of known concentration were applied to the slides and the water was allowed to evaporate to produce dry DNA samples. Half of the slides were irradiated with 290 MeV/u of carbon ions and a dose rate of 20 Gy/min. The other half of the slides were irradiated with helium nuclei of 150 MeV/hr and a dose rate of 12.6 Gy/min. Both sets of slides were irradiated with doses of 0-1,400 Gy with a 200 Gy step. After irradiation, the samples were re-dissolved in distilled water, frozen and transported on ice to the Czech Republic for processing. Samples were analyzed by agarose gel electrophoresis. The plasmid was evaluated separately to determine the degree of radiation induced lesions and further to incubation with enzymes recognizing basal damage. (authors)

Persistence of plasmids, cholera toxin genes, and prophage DNA in classical Vibrio cholerae O1.

OpenAIRE

Cook, W L; Wachsmuth, K; Johnson, S R; Birkness, K A; Samadi, A R

1984-01-01

Plasmid profiles, the location of cholera toxin subunit A genes, and the presence of the defective VcA1 prophage genome in classical Vibrio cholerae isolated from patients in Bangladesh in 1982 were compared with those in older classical strains isolated during the sixth pandemic and with those in selected eltor and nontoxigenic O1 isolates. Classical strains typically had two plasmids (21 and 3 megadaltons), eltor strains typically had no plasmids, and nontoxigenic O1 strains had zero to thr...

Destabilization of IncA and IncC plasmids by SGI1 and SGI2 type Salmonella genomic islands.

Science.gov (United States)

Harmer, Christopher J; Hamidian, Mohammad; Ambrose, Stephanie J; Hall, Ruth M

Both the Salmonella genomic islands (SGI) and the conjugative IncC plasmids are known to contribute substantially to the acquisition of resistance to multiple antibiotics, and plasmids in the A/C group are known to mobilize the Salmonella genomic island SGI1, which also carries multiple antibiotic resistance genes. Plasmid pRMH760 (IncC; A/C 2 ) was shown to mobilize SGI1 variants SGI1-I, SGI1-F, SGI1-K and SGI2 from Salmonella enterica to Escherichia coli where it was integrated at the preferred location, at the end of the trmE (thdF) gene. The plasmid was transferred at a similar frequency. However, we observed that co-transfer of the SGI and the plasmid was rarer. In E. coli to E. coli transfer, the frequency of transfer of the IncC plasmid pRMH760 was at least 1000-fold lower when the donor carried SGI1-I or SGI1-K, indicating that the SGI suppresses transfer of the plasmid. In addition, pRMH760 was rapidly lost from both E. coli and S. enterica strains that also carried SGI1-I, SGI1-F or SGI2. However, plasmid loss was not seen when the SGI1 variant was SGI1-K, which lacks two segments of the SGI1 backbone. The complete sequence of the SGI1-I and SGI1-F were determined and SGI1-K also carries two single base substitutions relative to SGI1-I. The IncA (A/C 1 ) plasmid RA1 was also shown to mobilize SGI2-A and though there are significant differences between the backbones of IncA and IncC plasmids, RA1 was also rapidly lost when SGI2-A was present in the same cell. We conclude that there are multiple interactions, both cooperative and antagonistic, between an IncA or IncC plasmid and the SGI1 and SGI2 family genomic islands. Copyright © 2016 Elsevier B.V. All rights reserved.

Comparative genomics of multidrug resistance-encoding IncA/C plasmids from commensal and pathogenic Escherichia coli from multiple animal sources.

Science.gov (United States)

Fernández-Alarcón, Claudia; Singer, Randall S; Johnson, Timothy J

2011-01-01

Incompatibility group A/C (IncA/C) plasmids have received recent attention for their broad host range and ability to confer resistance to multiple antimicrobial agents. Due to the potential spread of multidrug resistance (MDR) phenotypes from foodborne pathogens to human pathogens, the dissemination of these plasmids represents a public health risk. In this study, four animal-source IncA/C plasmids isolated from Escherichia coli were sequenced and analyzed, including isolates from commercial dairy cows, pigs and turkeys in the U.S. and Chile. These plasmids were initially selected because they either contained the floR and tetA genes encoding for florfenicol and tetracycline resistance, respectively, and/or the bla(CMY-2) gene encoding for extended spectrum β-lactamase resistance. Overall, sequence analysis revealed that each of the four plasmids retained a remarkably stable and conserved backbone sequence, with differences observed primarily within their accessory regions, which presumably have evolved via horizontal gene transfer events involving multiple modules. Comparison of these plasmids with other available IncA/C plasmid sequences further defined the core and accessory elements of these plasmids in E. coli and Salmonella. Our results suggest that the bla(CMY-2) plasmid lineage appears to have derived from an ancestral IncA/C plasmid type harboring floR-tetAR-strAB and Tn21-like accessory modules. Evidence is mounting that IncA/C plasmids are widespread among enteric bacteria of production animals and these emergent plasmids have flexibility in their acquisition of MDR-encoding modules, necessitating further study to understand the evolutionary mechanisms involved in their dissemination and stability in bacterial populations.

Comparative genomics of multidrug resistance-encoding IncA/C plasmids from commensal and pathogenic Escherichia coli from multiple animal sources.

Directory of Open Access Journals (Sweden)

Claudia Fernández-Alarcón

Full Text Available Incompatibility group A/C (IncA/C plasmids have received recent attention for their broad host range and ability to confer resistance to multiple antimicrobial agents. Due to the potential spread of multidrug resistance (MDR phenotypes from foodborne pathogens to human pathogens, the dissemination of these plasmids represents a public health risk. In this study, four animal-source IncA/C plasmids isolated from Escherichia coli were sequenced and analyzed, including isolates from commercial dairy cows, pigs and turkeys in the U.S. and Chile. These plasmids were initially selected because they either contained the floR and tetA genes encoding for florfenicol and tetracycline resistance, respectively, and/or the bla(CMY-2 gene encoding for extended spectrum β-lactamase resistance. Overall, sequence analysis revealed that each of the four plasmids retained a remarkably stable and conserved backbone sequence, with differences observed primarily within their accessory regions, which presumably have evolved via horizontal gene transfer events involving multiple modules. Comparison of these plasmids with other available IncA/C plasmid sequences further defined the core and accessory elements of these plasmids in E. coli and Salmonella. Our results suggest that the bla(CMY-2 plasmid lineage appears to have derived from an ancestral IncA/C plasmid type harboring floR-tetAR-strAB and Tn21-like accessory modules. Evidence is mounting that IncA/C plasmids are widespread among enteric bacteria of production animals and these emergent plasmids have flexibility in their acquisition of MDR-encoding modules, necessitating further study to understand the evolutionary mechanisms involved in their dissemination and stability in bacterial populations.

Mechanisms Involved in Acquisition of blaNDM Genes by IncA/C2 and IncFIIY Plasmids.

Science.gov (United States)

Wailan, Alexander M; Sidjabat, Hanna E; Yam, Wan Keat; Alikhan, Nabil-Fareed; Petty, Nicola K; Sartor, Anna L; Williamson, Deborah A; Forde, Brian M; Schembri, Mark A; Beatson, Scott A; Paterson, David L; Walsh, Timothy R; Partridge, Sally R

2016-07-01

blaNDM genes confer carbapenem resistance and have been identified on transferable plasmids belonging to different incompatibility (Inc) groups. Here we present the complete sequences of four plasmids carrying a blaNDM gene, pKP1-NDM-1, pEC2-NDM-3, pECL3-NDM-1, and pEC4-NDM-6, from four clinical samples originating from four different patients. Different plasmids carry segments that align to different parts of the blaNDM region found on Acinetobacter plasmids. pKP1-NDM-1 and pEC2-NDM-3, from Klebsiella pneumoniae and Escherichia coli, respectively, were identified as type 1 IncA/C2 plasmids with almost identical backbones. Different regions carrying blaNDM are inserted in different locations in the antibiotic resistance island known as ARI-A, and ISCR1 may have been involved in the acquisition of blaNDM-3 by pEC2-NDM-3. pECL3-NDM-1 and pEC4-NDM-6, from Enterobacter cloacae and E. coli, respectively, have similar IncFIIY backbones, but different regions carrying blaNDM are found in different locations. Tn3-derived inverted-repeat transposable elements (TIME) appear to have been involved in the acquisition of blaNDM-6 by pEC4-NDM-6 and the rmtC 16S rRNA methylase gene by IncFIIY plasmids. Characterization of these plasmids further demonstrates that even very closely related plasmids may have acquired blaNDM genes by different mechanisms. These findings also illustrate the complex relationships between antimicrobial resistance genes, transposable elements, and plasmids and provide insights into the possible routes for transmission of blaNDM genes among species of the Enterobacteriaceae family. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

CHARACTERIZATION OF SINGLE-STRAND ORIGINS OF CRYPTIC ROLLING-CIRCLE PLASMIDS FROM BACILLUS-SUBTILIS

NARCIS (Netherlands)

MEIJER, WJJ; VENEMA, G; BRON, S

1995-01-01

In this paper we describe the isolation and characterization of single strand origins (SSOs) of several cryptic Bacillus subtilis plasmids which use the rolling-circle mechanism of replication, The plasmids used in this study involved pTA1015, pTA1020, pTA1030, pTA1040, pTA1050 and pTA1060, The SSO

Characteristics of plasmids in multi-drug-resistant Enterobacteriaceae isolated during prospective surveillance of a newly opened hospital in Iraq.