Biochemical identifications were also performed using Alsina’s scheme (Alsina & Blanch, 1994a, b), optimized by Ottaviani et al. (2003), based on biochemical tests grouped into identification keys. Arginine dihydrolase, lysine decarboxylase, ornithine decarboxylase, acetoin production, N-acetyl-glucosamine assimilation, utilization of citrate and d-glucosamine responses were recorded from API selleck chemical strips. In addition, some indications from the Bergey’s Manual of Determinative Bacteriology (Holt et al., 1994) about assimilation activity, such as for capric acid and amygdaline,

were considered. Because of the extension of the identification scheme, only the identification of V. parahaemolyticus strains was followed. The biochemically identified V. parahaemolyticus strains were cultured in 3% NaCl tryptone soy broth (Oxoid), at 37±1 °C for 24 h, to confirm their identities by (1) PCR amplification and sequencing of the 16S rRNA gene and (2) PCR amplification to detect the presence of the toxR (Kim et al., 1999), tlh (Bej et al., 1999), tdh and trh genes (Bej

et al., 1999). Nucleic acid extraction was performed using the DNeasyTM Tissue Kit, Qiagen, according to the manufacturer’s instructions. Briefly, bacterial cultures Dabrafenib solubility dmso (1.5 mL) were centrifuged at 6000 g for 10 min and pellets were resuspended in a lysis buffer, then 20 μL of Proteinase K was added and the solution was incubated at 55 °C for 2 h. Then we added 200 μL of a buffer solution and the samples were incubated at 70 °C for 10 min. Finally, we added 200 μL of ethanol (96%), and after two centrifugations at 6800 g for 1 min, the DNA extracted was ready for PCR amplification.

The extract was quantified fluorometrically (Perkin Elmer LS50B) using the PicoGreen dsDNA quantitation kit (Molecular Probes). A portion of the 16S rRNA gene was amplified by a modification of the touchdown protocol (Don et al., 1991) using the universal primer 27F and the eubacterial-specific primer 1492R (Lane, 1991). An initial 94 °C denaturing step for 5 min was followed by 30 cycles of amplification (3-min denaturation at 94 °C; 1-min annealing starting at 65 °C for the first cycle reduced from 0.5 °C per cycle to 50 °C; 3-min extension at 72 °C), five additional cycles Uroporphyrinogen III synthase of amplification (3 min at 94 °C; 1 min at 50 °C; 3 min at 72 °C) and a final extension of 10 min at 72 °C. The detection of the toxR, tlh, tdh and trh genes was performed according to Kim et al. (1999) and Bej et al. (1999). For each amplification, the following reaction mixture was used: 1 μL of the template, 5 μL of 10 × HotMaster Taq Buffer with Mg2+ (Eppendorf), 5 μL of each primer (10 μM) (Sigma-Genosys Ltd), 1 μL of deoxynucleoside triphosphates (10 mM), 0.4 μL of Taq polymerase and H2O to a final volume of 50 μL. The PCR products from five different amplifications were electrophoresed on 0.8% agarose gels and stained with ethidium bromide (0.

For spleens, livers and caecal contents, significant differences of loads were determined using the Androgen Receptor Antagonist Mann–Whitney U-test. Samples with no detectable Salmonella were placed in the lowest rank, those with bacteria detected only following enrichment were placed in the next rank, and further samples were ranked according to the number of CFU. Differences were considered significant at the 5% level. HD11 avian macrophage-like cells (Beug et al., 1979) were seeded into 24-well plates at

a density of 2 × 105 cells per well in RPMI 1640 medium (Invitrogen, UK) supplemented with 10% foetal bovine serum (PAA laboratories Ltd, UK), 10% chicken serum (Sigma, UK), 2 mM L-glutamine, 100 U mL−1 penicillin/streptomycin, 2.5 μg mL−1 fungizone, hereafter referred to as HD11 medium. Cells were incubated for 48 h at 41 °C under 5% CO2. Twenty-four hours prior to assay, the cells were washed with 1× PBS and HD11 medium without fungizone and penicillin/streptomycin (HD11-Ab-free medium) was added. Salmonella strains were grown in L-broth statically at 37 °C overnight. HD11 cells were inoculated with 20 μL bacterial culture in triplicate and plates centrifuged at 30 g for 5 min. Bacteria in the inocula were enumerated by serial decimal dilution, plating onto CBA and an overnight incubation at 37 °C. Infected HD11 cells were incubated at 41 °C for 30 min to allow the uptake of bacteria.

Extracellular bacteria were removed by washing with PBS, and HD11 medium containing 100 μg mL−1 gentamicin was added to each well Selleck IWR1 followed by incubation for 2 h at 41 °C under 5% CO2. Cells were then washed with PBS and the medium was replaced with HD11 containing 20 μg mL−1 gentamicin. At 2, 4 and 6 h post Salmonella addition, cells were washed with PBS and lysed by incubation in 1 mL 0.1% (v/v) Triton X-100 in PBS for 10 min. Numbers of viable bacteria per well were determined by serial dilution, plating on CBA and an overnight incubation at 37 °C. The assay was performed in triplicate. Macrophage survival was examined

using a Cytotox lactate dehydrogenase assay (Promega, UK). Five genomic islands (R1, R3, R4, R5 and R6) present in the sequenced SEn strain P125109, but absent from Typhimurium LT2, and Typhi CT18 were identified by Davidson (2008). Adenosine triphosphate These loci were chosen for deletion. Comparative genome analysis and PCR screening showed that all these loci were also present in the avian-adapted serotype Gallinarum (Davidson, 2008; Thomson et al., 2008), although for this serotype R5 did not contain a ST64B phage-like sequence found in SEn. In previous analysis (Thomson et al., 2008), these loci were termed as regions of difference (ROD) and spanned slightly different genes to those in Davidson (2008) (Table 1). The genomic sequence of SEn Thirsk flanking the islands was determined by sequencing PCR products and shown to be identical to the published P125109 sequence (Thomson et al.

For spleens, livers and caecal contents, significant differences of loads were determined using the buy Dabrafenib Mann–Whitney U-test. Samples with no detectable Salmonella were placed in the lowest rank, those with bacteria detected only following enrichment were placed in the next rank, and further samples were ranked according to the number of CFU. Differences were considered significant at the 5% level. HD11 avian macrophage-like cells (Beug et al., 1979) were seeded into 24-well plates at

a density of 2 × 105 cells per well in RPMI 1640 medium (Invitrogen, UK) supplemented with 10% foetal bovine serum (PAA laboratories Ltd, UK), 10% chicken serum (Sigma, UK), 2 mM L-glutamine, 100 U mL−1 penicillin/streptomycin, 2.5 μg mL−1 fungizone, hereafter referred to as HD11 medium. Cells were incubated for 48 h at 41 °C under 5% CO2. Twenty-four hours prior to assay, the cells were washed with 1× PBS and HD11 medium without fungizone and penicillin/streptomycin (HD11-Ab-free medium) was added. Salmonella strains were grown in L-broth statically at 37 °C overnight. HD11 cells were inoculated with 20 μL bacterial culture in triplicate and plates centrifuged at 30 g for 5 min. Bacteria in the inocula were enumerated by serial decimal dilution, plating onto CBA and an overnight incubation at 37 °C. Infected HD11 cells were incubated at 41 °C for 30 min to allow the uptake of bacteria.

Extracellular bacteria were removed by washing with PBS, and HD11 medium containing 100 μg mL−1 gentamicin was added to each well TGF-beta inhibitor followed by incubation for 2 h at 41 °C under 5% CO2. Cells were then washed with PBS and the medium was replaced with HD11 containing 20 μg mL−1 gentamicin. At 2, 4 and 6 h post Salmonella addition, cells were washed with PBS and lysed by incubation in 1 mL 0.1% (v/v) Triton X-100 in PBS for 10 min. Numbers of viable bacteria per well were determined by serial dilution, plating on CBA and an overnight incubation at 37 °C. The assay was performed in triplicate. Macrophage survival was examined

using a Cytotox lactate dehydrogenase assay (Promega, UK). Five genomic islands (R1, R3, R4, R5 and R6) present in the sequenced SEn strain P125109, but absent from Typhimurium LT2, and Typhi CT18 were identified by Davidson (2008). very These loci were chosen for deletion. Comparative genome analysis and PCR screening showed that all these loci were also present in the avian-adapted serotype Gallinarum (Davidson, 2008; Thomson et al., 2008), although for this serotype R5 did not contain a ST64B phage-like sequence found in SEn. In previous analysis (Thomson et al., 2008), these loci were termed as regions of difference (ROD) and spanned slightly different genes to those in Davidson (2008) (Table 1). The genomic sequence of SEn Thirsk flanking the islands was determined by sequencing PCR products and shown to be identical to the published P125109 sequence (Thomson et al.

Results.  Tooth brushing was

stared at a mean age of 16 months. Thirty-seven per cent of the pre-schoolers used a toothbrush for cleaning their teeth and the brushing habits were mainly (70%) introduced by mothers. The majority (80%) of children’s tooth brushing at the age of 3 years and above was supervised by mothers. Younger children were frequently supervised in tooth brushing than older children (P < 0.05) Conclusions.  In summary, pre-school children of Sharjah (UAE) were introduced to tooth brushing at a mean age of 16 months. Mothers played a pivotal role in introducing and teaching the child how to brush. There was no positive correlation between the brushing PI3K inhibitor behaviour of the mothers and their children. In most cases, the children’s brushing was supervised by their mother when they were above 25 months of age. In children less than 12 months of age tooth brushing was not started at all. “
“International Journal of Paediatric Dentistry 2011; 21: 151–159 Aim.  To establish a threshold cemantoenamel junction

(CEJ)–alveolar bone crest (ABC) distance in healthy 6- to 9-year-old Jordanian children and determine the effect of pathological changes, physiological changes, gender, and age on the CEJ–ABC distance. Design.  Bitewing radiographs were made for 539 6- to 9-year-old children. Natural Product Library supplier Plaque index (PI), gingival index (GI), calculus index (CI), DMFS score, and pocket depth were all assessed through clinical examination. CEJ–ABC distance was measured Acyl CoA dehydrogenase from radiographs at the mesial surface of permanent first molars (PFM), and the mesial and distal surfaces of primary molars. Results.  The CEJ–ABC distance ranged from 0.00 to 4.49 mm, the mean for all surfaces was 0.84 ± 0.44 mm, no gender or age group differences were found. The mesial surface of the PFMs had the smallest mean CEJ–ABC

distance. The CEJ–ABC distances were greater in the maxilla than in the mandible. No significant effect of PI, GI or CI on CEJ–ABC distance was found. Caries, faulty restorations, exfoliation, and partial eruption adjacent to measured surfaces had significant effect on the CEJ–ABC distance. Conclusion.  The mean CEJ–ABC distance was <1 mm. Threshold CEJ–ABC distances of 1.0 and 1.5 mm for PFMs and primary molars, respectively, are suggested to be used in 6- to 9-year-old children. "
“International Journal of Paediatric Dentistry 2013; 23: 72–76 Background.  It has been suggested that the widespread use of fluorides could interfere in the prevalence of clinically undetected occlusal dentine caries. Aim.  The objective of this study was to determine the role of public water fluoridation and fluoride dentifrice on the prevalence of hidden caries in 8–10-year-old children. Design.  Clinical and radiographic data on schoolchildren collected in an epidemiologic study in Porto Alegre, Brazil, at two moments, 1975 (n = 228) and 1996 (n = 213), were analysed. Only the first permanent molars were studied.

04 and stata statistical software (Version 6.0, College Station, TX). The statistical significance of differences in dichotomous variables was determined by using χ2 tests with Fischer’s two-tailed exact test, and by using t-test or U-test of Mann–Whitney for quantitative variables. All variables correlated

in univariate analysis with imported malaria were included in a stepwise backward regression model (significance level for exclusion of p≥ 0.25) to identify predictors of the disease. Logistic regression analysis was performed by stata statistical software (Version 6.0). The sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were determined. A total of 272 travelers, IDH inhibitor 54 malaria cases and 218 controls, were included. The M/F ratio was 1.34 (116 F and 156 M), and the mean age 37.4 (±11.9) years. They consisted of 152 tourists (55.9%), 58 immigrants (21.3%), 33 expatriates (12.1%), and 29 business travelers (10.7%). The following regions were visited: Africa (n = 169; 62.1%), Asia (n = 47; 17.3%), America (n = 14; 5.1%), and Caribbean (n = 12; 4.4%). The median duration of travel was 15 days (1–1095 days). Forty-seven patients (17.3%)

stayed in the tropics for more than 3 months. The median interval between return and presentation was 6 days (1–151 days). The median lag time between the onset of the symptoms and presentation was 7.5 days (1–90 days). Symptoms GSK-3 phosphorylation started during travel in 38%

of our patients. Seventy-three percent of the patients had taken medical advice before travel (general practitioner 7%; specialist in tropical disease 61.8%; travel agency 3.3%; telephonic center 1.5%). The chemoprophylaxis was inadequate in 170 cases (62.5%), regarding the choice of drug (n = 44) or adherence to prophylaxis (n = 156). The characteristics of patients are listed in Table 1. Of the 272 febrile patients, 54 (19.8%) were diagnosed with imported malaria (= case ). Of these 54 cases of malaria, 36 were because of Plamodium falciparum (67%), Alanine-glyoxylate transaminase 14 cases to P vivax (26%), and 4 to P ovale (7%) (none for P malariae and P knowlesi) whereas 45 cases were acquired in sub-Saharan Africa (83%). The main diagnosis in the 218 controls were as follows: bacterial enteritis (n = 50), bacterial pneumonia (n = 20), infectious cellulitis (n = 20), pyelonephritis (n = 13), prostatis (n = 9), dengue fever (n = 16), viral (non HIV) primary infection (EBV, CMV, parvovirus B19) (n = 11), tuberculosis (n = 12), invasive schistosomiasis (n = 4), rickettsiosis (n = 3), brucellosis (n = 2), and primary HIV infection (n = 2). No diagnosis was made in 15 cases (5.5%) (Table 2). Overall an imported disease was diagnosed in 30.5% of these febrile patients.

To ascertain all ovarian cancer-related deaths, information was sought from the community registration files and/or hospital medical records. Data on the following variables were retrieved from medical records in the participating hospitals: FIGO stage, histological type, grade of differentiation, cytology

of ascites, residual disease after surgery, and regime and frequency of chemotherapy. Baseline data were also utilized from our previous case-control study.16 The data were coded and analyzed using the SPSS package (SPSS, Chicago, IL, USA). Survival time (in years) was calculated from the date of diagnosis to the date of death (event) or date of interview (censored). The Kaplan–Meier technique was applied to characterize the survival experiences according to tubal ligation selleck compound status pre-diagnosis. The intraclass correlation coefficient (ICC) and Kappa statistic were used to examine the agreement in reported smoking, alcohol consumption, and tea drinking post-diagnosis between the patients and their next of kin. Univariate analysis was first undertaken to screen for potentially important variables for subsequent multivariate analysis.

Separate Cox regression models were fitted to each categorical or quantitative variable in the study, and the corresponding linear trend test was performed. The effects of tubal ligation, reproductive and hormonal factors on ovarian cancer survival were assessed using adjusted hazard ratios (HR) and associated 95% confidence intervals (CI), accounting for age at diagnosis, usual body selleck chemicals llc mass index (BMI), FIGO stage, grade of histopathological differentiation,

ascites, and chemotherapy status. These variables had been reported to influence ovarian cancer survival or were significant confounders according to the univariate results.18–20 By 5 years after diagnosis, 79 patients of the 195 cases in the original cohort were deceased. The details of their causes of death, obtained from hospital records, showed that all 79 patients died from ovarian cancer. Seventy-seven Protein tyrosine phosphatase patients died from spread of their cancer, while two deaths were recorded as being related to the side-effects of chemotherapy. In 30 cases in the questionnaire was administered to both the patient and a close relative, there were no important differences in smoking, alcohol consumption, and tea drinking post-diagnosis between the patients and their corresponding next of kin. The ICC ranged from 0.88 for the quantity of dried tea-leaf consumed to 0.96 for the frequency of new batches brewed. The agreement was high for smoking and tea drinking (Kappa = 0.99 and 0.93 respectively) and moderate for alcohol consumption (Kappa = 0.46), further supporting the reliability of information provided by the proxies.

0% microcrystalline cellulose and 0.1% yeast extract in the basal medium with 1% agar after step dilutions. Individual colonies were collected from the plate and inoculated in the basal medium containing 0.5% cellobiose and 0.1% yeast

extract. After five consecutive transfers, a fermentation experiment was carried out using the 200 mL basal medium containing 2 g of FP as the carbon source. The concentrations of fermentation products were analyzed by high-performance liquid selleck chromatography (HPLC) using an Aminex HPX-87H column (Bio-Rad, Hercules, CA). The detected fermentation products included acetate, ethanol, butyric acid, butanol, cellobiose and glucose. The fermentation broth was taken at 72 h to determine the crude enzyme activities. The sample was centrifuged at 10 000 g for 5 min, and the supernatant was used as crude extract. Clostridium thermocellum LQR1 was used as control, which was cultivated in CM3 medium with 1% FP as the carbon source (Weimer & Zeikus, 1977), and the crude enzyme was taken after 72 h cultivation. All assays were performed at 60 °C in 20 mM PIPES [piperazine-N,N-bis (2-ethanesulfonic acid)] buffer (pH 7) under static conditions for 60 min. FP hydrolysis activity (FPase) was determined using Whatman No. 1 FP and was expressed in filter paper units (FPU) (Wood & Kellogg, 1988). One FPU was defined as the

amount of enzyme capable of producing 1 μmol of reducing sugars in 1 min. Endoglucanase and xylanase activities were measured using carboxymethylcellulose (CMC) and birch wood xylan (Sigma-Aldrich), respectively, with Cabozantinib manufacturer a 1% solution of CMC or xylan as the substrate. The β-glucosidase, β-xylosidase and pNPCase activities were determined using p-nitrophenyl-β-d-glucoside, p-nitrophenyl-β-d-xyloside and p-nitrophenyl-cellobioside (Sigma-Aldrich) as the substrate, respectively (Wood & Kellogg, 1988). One unit of enzyme releases 1 μmol equivalent of glucose, xylose or p-nitrophenol per minute. The release of reducing sugars was measured by the dinitrosalicylic colorimetric

(DNS) during method (Miller, 1959). Protein concentrations were determined with the Bradford assay kit (Biomed, Bejing, China) with bovine serum albumin as the standard. After five consecutive transfers using basal medium with Avicel as the growth substrate, total DNA of enrichment culture was extracted using the E.Z.N.A.™ Soil DNA Kit (Omega Bio-Tek). The DNA obtained from each set of triplicate extractions was pooled. Using the universal oligonucleotide primers 27F and 1492R, the extracted DNA was used in triplicate PCR amplifications targeting the 16S rRNA gene. PCR amplifications were prepared with 25 μL 2× Taq PCR Master Mix (Biomed), and 1 μM of each primer for a final volume of 50 μL, using 30 cycles of 94 °C (30 s), 50 °C (45 s), and 72 °C (90 s), with an initial denaturation at 95 °C (5 min) and a final extension at 72 °C (5 min).

The mean interval since the previous medical first aid education was 4.7 years (SD: selleck chemicals 1.8 y). The nautical

officers faced a simulated cardiac arrest situation (“person with no pulse and no spontaneous breathing”) by use of a dressed manikin (Defib Trainer Advanced, Ambu, Bad Nauheim, Germany). They were instructed to perform resuscitation actions as fast as possible in single-person method and by using an available AED. In total, 400 defibrillation drills were executed; each drill consisted of four different steps: (1) switching on the AED; (2) placing the pads on the “patient’s chest”; (3) connecting the pads to the AED; and (4) delivering a shock.12 A trainer timed each step. The total time of the first three steps was defined

as “time until start of ECG analysis” and the total time of all the steps as “time to first shock.” The parameters were chosen according to Fleischhackl Gemcitabine datasheet and colleagues.13 The seafarers were randomly allocated to one of the following four AEDs: HeartStart FR2+ (Phillips, Amsterdam, the Netherlands), HeartSave AED-M (Metrax, Rottweil, Germany), Defi FRED easy (Schiller, Baar, Switzerland), or AED Plus (Zoll, Chelmsford, MA, USA). All the devices complied with the legal requirements according to the German Ordinance for the Medical Care on Seagoing Vessels.1 To explore the resuscitation training effect, 60 nautical officers from courses 1 to 7 were randomized to one of the four AEDs. The officers’ performance when using the defibrillators was tested twice during the classes: at the beginning of the refresher course and after attending a 7-hour resuscitation training including instruction in the AED handling (in total 120 drills). The training was based on the recommendations of the German Resuscitation Council14 and the manufacturers’ manuals. In the second part of the study, 70 nautical seafarers from courses 8 to 14 performed four resuscitation drills, each

person dealing with all four available AEDs (in total 280 drills) in alternating order. The drills took place after the regular resuscitation training PARP inhibitor in the classes. Additionally, the user-friendliness of a one-piece electrode (AED Plus) was compared with the user-friendliness of two-piece electrodes (AED Plus). Sex, age, and rank as well as preexisting experiences with the handling of AEDs were recorded anonymously. In the context of the survey of resuscitation training effect, the officers were asked about the handling of AEDs and their general benefit for shipboard use based on a scale from 1 to 5 (from best to worst vote). For the “Four-device comparison,” the officers had to answer questions related to the comprehensibility of the AED and the electrodes. Furthermore, the nautical officers could state in free text what they liked and disliked on the respective devices. Data were analyzed using SPSS for Windows (version 18.0; SPSS GmbH Software, Munich, Germany).

4.4.2.4 Treatment. • First line treatment for CMV colitis is intravenous ganciclovir (5 mg/kg Gefitinib cost twice daily) for 14–28 days (category Ib recommendation). CMV colitis has traditionally been treated with ganciclovir 5 mg/kg bd iv for 14–28 days

[62]. Caution should be used in initiating treatment with the oral medication valganciclovir as there is a theoretical concern of decreased absorption, but HIV and non-HIV-related cases of CMV colitis have been successfully treated [63]. Intravenous foscarnet (90 mg/kg twice daily) for 14–28 days is used as an alternative [64,65]. Therapeutic drug monitoring may be required to ensure adequate HAART absorption (category IV recommendation). Chronic maintenance therapy is not routinely recommended in gastrointestinal disease unless patients relapse after induction therapy ceases [64]. All individuals with CMV involving the gastrointestinal tract should have prompt ophthalmological evaluation to exclude concomitant CMV retinitis and if this is present treatment and secondary prophylaxis should be initiated as recommended (see section 5.1 CMV retinitis). 4.4.2.5 Impact of HAART. Continuous use of effective HAART is required to prevent relapse. 4.4.3.1 Background and epidemiology. Cryptosporidium, a protozoan

parasite, was the most common pathogen in HIV-antibody-positive individuals with chronic diarrhoea in the pre-HAART era. Those at greatest risk Obeticholic Acid research buy of infection are individuals with a CD4 count <100 cells/μL [66]. It predominantly infects the small bowel mucosa, Clostridium perfringens alpha toxin but in

the immunocompromised patient, the large bowel and extraintestinal sites may be involved. The most common species infecting humans in the UK are C. hominis and the zoonotic species C. parvum and C. meleagridis [67]. In areas with a low rate of environmental contamination and where HAART is widely available, cryptosporidiosis has an incidence of<1 per 100 person-years among HIV-seropositive individuals. Ingestion of cryptosporidium oocysts leads to transmission of the parasite. Faeces from infected animals, including humans, can contaminate the water supply with viable oocysts, which are highly resistant to chlorination. Transmission may also occur during sex, particularly via the faecal–oral route [68]. 4.4.3.2 Presentation. Cryptosporidiosis should be considered in any individual with an acute or subacute history of profuse, non-bloody watery diarrhoea. In immunocompetent individuals, cryptosporidiosis presents as an acute, self-limiting diarrhoeal illness, which may be accompanied by nausea, abdominal cramps and low-grade pyrexia, lasting up to 14 days. In HIV-seropositive individuals with a CD4 count <50 cells/μL there is a worsening of these symptoms, and stool volumes of up to 24 litres per day have been described, although more commonly, 2–3 litres per day are passed [69]. Malabsorption may be present.

volcanii and E. coli. pAJ successfully expressed proteins in Hfx. volcanii or E. coli, rendering it feasible to express target proteins in corresponding domains. In addition, pAJ contains a multiple cloning site with 11 restriction sites and a 6×His tag sequence, and the vector size was decreased to 8903 bp. To the best of our knowledge, pAJ is the first reported shuttle expression vector that can express proteins in both Bacteria and Archaea. Importantly, pAJ can even express the haloarchaeal heat shock selleck chemical protein DnaK in both domains. In conclusion, this novel vector only provides researchers with a new means to manipulate genes

or express proteins in Haloarchaea but also serves as a convenient tool for the comparative study of the function of some highly conserved genes in Haloarchaea and in Bacteria. “
“The present study describes the assimilation of phenanthrene by an aerobic bacterium, Ochrobactrum sp. strain PWTJD, isolated from municipal waste-contaminated soil sample

utilizing phenanthrene as a sole source of carbon and energy. The isolate was identified as Ochrobactrum sp. based on the morphological, nutritional and biochemical characteristics as well as 16S rRNA gene sequence analysis. A combination of chromatographic analyses, oxygen uptake assay and enzymatic studies confirmed the degradation of phenanthrene by the strain PWTJD via 2-hydroxy-1-naphthoic acid, salicylic acid and catechol. The strain PWTJD could also utilize 2-hydroxy-1-naphthoic acid and selleck chemicals salicylic acid, while the former was metabolized by a ferric-dependent meta-cleavage dioxygenase. In the lower pathway, salicylic acid was metabolized to catechol and was further degraded by catechol 2,3-dioxygenase to 2-hydroxymuconoaldehyde acid, ultimately leading to tricarboxylic acid cycle intermediates. This is the first report of

the complete degradation of a polycyclic aromatic hydrocarbon molecule by Gram-negative Ochrobactrum sp. describing the involvement of the meta-cleavage pathway of 2-hydroxy-1-naphthoic acid in phenanthrene assimilation. Polycyclic aromatic hydrocarbons (PAHs) comprise a large see more and diverse group of priority environmental pollutants, which are ubiquitous contaminants derived from both natural and anthropogenic activities. Their abundance in the environment is of great concern, because many of them have been shown to be toxic, mutagenic and/or carcinogenic in nature (Mastrangelo et al., 1996; Marston et al., 2001; Xue & Warshawsky, 2005). The stability, persistency and carcinogenic index of PAHs increase with an increase in the number of aromatic rings, structural angularity and hydrophobicity (Marston et al., 2001). Phenanthrene has often been used as a model compound to study the microbial metabolism of bay- and K-region-containing PAHs because its structural skeletons are found in many carcinogenic PAHs.