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characterization of a novel agrobacterium tumefaciens galactarolactone cycloisomerase enzyme for direct conversion of d-galactarolactone to 3-deoxy-2-keto-l-threo-hexarate.microorganisms use different pathways for d-galacturonate catabolism. in the known microbial oxidative pathway, d-galacturonate is oxidized to d-galactarolactone, the lactone hydrolyzed to galactarate, which is further converted to 3-deoxy-2-keto-hexarate and α-ketoglutarate. we have shown recently that agrobacterium tumefaciens strain c58 contains an uronate dehydrogenase (at udh) that oxidizes d-galacturonic acid to d-galactarolactone. here we report identification of a novel enzyme from the s ...201222493433
haemophilus parasuis serovars isolated from pathological samples in northern italy.from january 2007 to december 2011, a total of 106 haemophilus parasuis strains isolated from pigs were serotyped by agar gel diffusion test (dg). serovar 4 was the most prevalent (24.5%), followed by serovar 13 (19.8%) and serovar 5 (11.3%). twenty-nine strains were non-typeable (27.3%). the strains were divided into two groups, depending on whether they were isolated from specific pathological lesions of systemic disease such as polyserositis, arthritis or meningitis (73 cases of 106) or from ...201322494561
evaluation of the bruker biotyper and vitek ms matrix-assisted laser desorption ionization-time of flight mass spectrometry systems for identification of nonfermenting gram-negative bacilli isolated from cultures from cystic fibrosis patients.the bruker biotyper and vitek ms matrix-assisted laser desorption ionization-time of flight (maldi-tof) mass spectrometry (ms) instruments were evaluated for the identification of nonfermenting gram-negative bacilli (nfgnb) by a blinded comparison to conventional biochemical or molecular methods. two hundred nfgnb that were recovered from cultures from cystic fibrosis patients in the university of iowa health care (uihc) microbiology laboratory between 1 january 2006 and 31 october 2010 were sen ...201222495566
regulation and evolution of malonate and propionate catabolism in proteobacteria.bacteria catabolize malonate via two pathways, encoded by the mdc and mat genes. in various bacteria, transcription of these genes is controlled by the gntr family transcription factors (tfs) matr/mdcy and/or the lysr family transcription factor mdcr. propionate is metabolized via the methylcitrate pathway, comprising enzymes encoded by the prp and acn genes. prpr, the fis family sigma 54-dependent transcription factor, is known to be a transcriptional activator of the prp genes. here, we report ...201222505679
[expression and characterization of the dermonecrotic toxin gene of bordetella bronchiseptica].dermonecrotic toxin (dnt) is identified as one of the most important virulence factor of bordetella bronchiseptica. the complete coding sequence (4 356 bp) of the dnt gene was cloned into the prokaryotic expression vector pet-28a, and expressed in the eschierichia coli bl21 (de3) under iptg (isopropyl-beta-d-thiogalactopyranoside) induction. the recombinant his6-dnt protein showed immunological reactivity in the western-blot analysis. the recombinant protein was purified from crude lysates of bl ...201122506412
the multifaceted roles of neutrophil gelatinase associated lipocalin (ngal) in inflammation and cancer.neutrophil gelatinase associated lipocalin (ngal), also known as oncogene 24p3, uterocalin, siderocalin or lipocalin 2, is a 24kda secreted glycoprotein originally purified from a culture of mouse kidney cells infected with simian virus 40 (sv-40). subsequent investigations have revealed that it is a member of the lipocalin family of proteins that transport small, hydrophobic ligands. since then, ngal expression has been reported in several normal tissues where it serves to provide protection ag ...201222513004
an improved immunofluorescent reagent for rapid, direct detection of bordetella pertussis. 199522514375
experimental actinobacillus pleuropneumoniae challenge in swine: comparison of computed tomographic and radiographic findings during disease.in pigs, diseases of the respiratory tract like pleuropneumonia due to actinobacillus pleuropneumoniae (app) infection have led to high economic losses for decades. further research on disease pathogenesis, pathogen-host-interactions and new prophylactic and therapeutic approaches are needed. in most studies, a large number of experimental animals are required to assess lung alterations at different stages of the disease. in order to reduce the required number of animals but nevertheless gather ...201222546414
interleukin-10 induction is an important virulence function of the yersinia pseudotuberculosis type iii effector yopm.pathogenic yersinia species modulate host immune responses through the activity of a plasmid-encoded type iii secretion system and its associated effector proteins. one effector, yopm, is a leucine-rich-repeat-containing protein that is important for virulence in murine models of yersinia infection. although the mechanism by which yopm promotes virulence is unknown, we previously demonstrated that yopm was required for the induction of high levels of the immunosuppressive cytokine interleukin-10 ...201222547545
isolation of antibacterial compounds from quercus dilatata l. through bioassay guided fractionation.four medicinal plants (chrozophora hierosolymitana spreng, chrysanthemum leucanthemum l., ephedra gerardiana wall. ex stapf, and quercus dilatata l.) used by indigenous healers to treat various infectious diseases were selected for the present study. the major objective of the present study was isolation and characterization of antimicrobial components from the crude plant extracts using bioassay guided fractionation.201222554280
multiplex pcr to identify macrolide resistance determinants in mannheimia haemolytica and pasteurella multocida.the bacterial pathogens mannheimia haemolytica and pasteurella multocida are major etiological agents in respiratory tract infections of cattle. although these infections can generally be successfully treated with veterinary macrolide antibiotics, a few recent isolates have shown resistance to these drugs. macrolide resistance in members of the family pasteurellaceae is conferred by combinations of at least three genes: erm(42), which encodes a monomethyltransferase and confers a type i mls(b) ( ...201222564832
recurrent respiratory infection caused by bordetella bronchiseptica in an immunocompetent infant.bordetella bronchiseptica rarely infects immunocompetent humans. we report an unusual case of recurrent pertussis-like syndrome caused by b. bronchiseptica in a 7-month-old immunocompetent boy. molecular analysis demonstrated that the isolates from the child and mother were identical.201222572751
natural and experimental helicobacter pullorum infection in brown norway rats.helicobacter pullorum is an enterohepatic helicobacter species (ehs) that was recently reported as a naturally acquired infection in mice. faecal samples from 18 out of 20 brown norway (bn) rats, housed in the same barrier as the h. pullorum-infected mice, were positive for h. pullorum using species-specific pcr. in addition, we determined whether h. pullorum was able to persistently colonize the gastrointestinal tract and/or biliary tree and elicit tissue inflammation as well as a serum igg res ...201222580914
immuno-epidemiology of chronic bacterial and helminth co-infections: observations from the field and evidence from the laboratory.co-infections can alter the host immune responses and modify the intensity and dynamics of concurrent parasitic species. the extent of this effect depends on the properties of the system and the mechanisms of host-parasite and parasite-parasite interactions. we examined the immuno-epidemiology of a chronic co-infection to reveal the immune mediated relationships between two parasites colonising independent organs, and the within-host molecular processes influencing the dynamics of infection at t ...201222584129
the bordetella pertussis model of exquisite gene control by the global transcription factor bvga.bordetella pertussis causes whooping cough, an infectious disease that is reemerging despite widespread vaccination. a more complete understanding of b. pertussis pathogenic mechanisms will involve unravelling the regulation of its impressive arsenal of virulence factors. here we review the action of the b. pertussis response regulator bvga in the context of what is known about bacterial rna polymerase and various modes of transcription activation. at most virulence gene promoters, multiple dime ...201222628479
isolation of a potent antibiotic producer bacterium, especially against mrsa, from northern region of the persian gulf.nowadays, emergence and prevalence of mrsa (methicillin resistant staphylococcus aureus) strain have become a great global concern in 21st century, so, it is necessary to discover new antibiotics against this pathogen. the aim of this study was isolation and evaluation marine bacteria from the persian gulf in order to finding antibiotic compounds against some pathogenic bacteria. for this purpose, water and sediment samples were collected from the persian gulf during march to october 2009. the a ...201222642595
nad (+) -dependent formate dehydrogenase from plants.nad(+)-dependent formate dehydrogenase (fdh, ec 1.2.1.2) widely occurs in nature. fdh consists of two identical subunits and contains neither prosthetic groups nor metal ions. this type of fdh was found in different microorganisms (including pathogenic ones), such as bacteria, yeasts, fungi, and plants. as opposed to microbiological fdhs functioning in cytoplasm, plant fdhs localize in mitochondria. formate dehydrogenase activity was first discovered as early as in 1921 in plant; however, until ...201122649703
bacterial cell wall compounds as promising targets of antimicrobial agents i. antimicrobial peptides and lipopolyamines.the first barrier that an antimicrobial agent must overcome when interacting with its target is the microbial cell wall. in the case of gram-negative bacteria, additional to the cytoplasmic membrane and the peptidoglycan layer, an outer membrane (om) is the outermost barrier. the om has an asymmetric distribution of the lipids with phospholipids and lipopolysaccharide (lps) located in the inner and outer leaflets, respectively. in contrast, gram-positive bacteria lack om and possess a much thick ...201222664072
multilocus sequence analysis of isolates of achromobacter from patients with cystic fibrosis reveals infecting species other than achromobacter xylosoxidans.a multilocus sequence analysis (mlsa) scheme was developed for characterization of strains and species from the genus achromobacter, which are increasingly recovered from patients with cystic fibrosis (cf). five conserved housekeeping genes were selected for the mlsa, which was applied to a diverse collection of 77 strains originating from europe, asia, and south america and including type strains of the seven recognized achromobacter species, six environmental strains, eight non-cf clinical str ...201222675125
development and characterization of attenuated metabolic mutants of bordetella bronchiseptica for applications in vaccinology.bordetella bronchiseptica is an important pathogen causing a number of veterinary respiratory syndromes in agriculturally important and food-producing confinement-reared animals, resulting in great economic losses annually amounting to billions of euros worldwide. currently available live vaccines are incompletely satisfactory in terms of efficacy and safety. an efficient vaccine for livestock animals would allow reducing the application of antibiotics, thereby preventing the massive release of ...201322676396
the type iii secreted protein bspr regulates the virulence genes in bordetella bronchiseptica.bordetella bronchiseptica is closely related with b. pertussis and b. parapertussis, the causative agents of whooping cough. these pathogenic species share a number of virulence genes, including the gene locus for the type iii secretion system (t3ss) that delivers effector proteins. to identify unknown type iii effectors in bordetella, secreted proteins in the bacterial culture supernatants of wild-type b. bronchiseptica and an isogenic t3ss-deficient mutant were compared with itraq-based, quant ...201222701731
synthetic oligosaccharides as tools to demonstrate cross-reactivity between polysaccharide antigens.escherichia coli o148 is a nonencapsulated enterotoxigenic (etec) gram negative bacterium that can cause diarrhea, hemorrhagic colitis, and hemolytic uremic syndrome in humans. the surface-exposed o-specific polysaccharide (o-sp) of the lipopolysaccharide of this bacterium is considered both a virulence factor and a protective antigen. it is built up of the linear tetrasaccharide repeating unit [3)-α-l-rhap-(1→2)-α-d-glcp-(1→3)-α-d-glcnacp-(1→3)-α-l-rhap-(1→] differing from that of the o-sp of s ...201222713129
the limitations of draft assemblies for understanding prokaryotic adaptation and evolution.the de novo assembly of next generation sequencing data is a daunting task made more difficult by the presence of genomic repeats or transposable elements, resulting in an increasing number of genomes designated as completed draft assemblies. we created and assembled idealized sequence data sets for cupriavidus metallidurans ch34, caulobacter sp. k31, gramella forsetii kt0803, rhodobacter sphaeroides 2.4.1 and bordetella bronchiseptica rb50. in addition to confirming the role of transposable ele ...201222750556
vaccine potential of an attenuated pasteurella multocida that expresses only the n-terminal truncated fragment of p. multocida toxin in pigs.previously we described the development of an attenuated pasteurella multocida mutant that expresses only the n-terminal truncated fragment of p. multocida toxin (n-pmt) and its protective effects in a mouse model. this paper details our evaluation of the vaccine potential of this mutant strain in pigs. pigs vaccinated with the mutant showed significantly higher rates of antibody induction and lower nasal conchal (turbinate) scores for atrophic rhinitis than controls, which suggests that this mu ...201222754098
comparison of the efficacy of amoxicillin-clavulanic acid, cefovecin, and doxycycline in the treatment of upper respiratory tract disease in cats housed in an animal shelter.to compare efficacy of amoxicillin-clavulanic acid, cefovecin, and doxycycline in shelter-housed cats with clinical signs of upper respiratory tract disease (urtd).201222765368
voluntary ingestion of antiparasitic drugs emulsified in honey represents an alternative to gavage in mice.the oral route is the most frequently used method of drug intake in humans. oral administration of drugs to laboratory animals such as mice typically is achieved through gavage, in which a feeding needle is introduced into the esophagus and the drug is delivered directly into the stomach. this method requires technical skill, is stressful for animals, and introduces risk of injury, pain and morbidity. here we investigated another method of drug administration. the benzimidazole derivative albend ...201222776122
a multilocus sequence typing scheme implies population structure and reveals several putative novel achromobacter species.the genus achromobacter currently is comprised of seven species, including achromobacter xylosoxidans, an opportunistic and nosocomial pathogen that displays broad-spectrum antimicrobial resistance and is recognized as causing chronic respiratory tract infection in persons with cystic fibrosis (cf). to enable strain typing for global epidemiologic investigations, to clarify the taxonomy of "achromobacter-like" strains, and to elucidate the population structure of this genus, we developed a genus ...201222785192
analysis of bacterial biofilms using nmr-based metabolomics.infectious diseases can be difficult to cure, especially if the pathogen forms a biofilm. after decades of extensive research into the morphology, physiology and genomics of biofilm formation, attention has recently been directed toward the analysis of the cellular metabolome in order to understand the transformation of a planktonic cell to a biofilm. metabolomics can play an invaluable role in enhancing our understanding of the underlying biological processes related to the structure, formation ...201222800371
glycerol monolaurate antibacterial activity in broth and biofilm cultures.glycerol monolaurate (gml) is an antimicrobial agent that has potent activity against gram-positive bacteria. this study examines gml antibacterial activity in comparison to lauric acid, in broth cultures compared to biofilm cultures, and against a wide range of gram-positive, gram-negative, and non-gram staining bacteria.201222808139
the structure- and metal-dependent activity of escherichia coli pgab provides insight into the partial de-n-acetylation of poly-β-1,6-n-acetyl-d-glucosamine.exopolysaccharides are required for the development and integrity of biofilms produced by a wide variety of bacteria. in escherichia coli, partial de-n-acetylation of the exopolysaccharide poly-β-1,6-n-acetyl-d-glucosamine (pnag) by the periplasmic protein pgab is required for polysaccharide intercellular adhesin-dependent biofilm formation. to understand the molecular basis for pnag de-n-acetylation, the structure of pgab in complex with ni(2+) and fe(3+) have been determined to 1.9 and 2.1 å r ...201222810235
dual mechanism of protection by live attenuated bordetella pertussis bpze1 against bordetella bronchiseptica in mice.bordetella bronchiseptica, a gram-negative bacterium, causes chronic respiratory tract infections in a wide variety of mammalian hosts, including man, and no human vaccine is currently available. acellular pertussis vaccines protect poorly against b. bronchiseptica, although they contain cross-reactive antigens. we have recently developed bordetella pertussis bpze1, a novel, live attenuated pertussis vaccine, currently completing phase i clinical trials in humans, and found that it protects agai ...201222814407
protective immunity conferred by the c-terminal fragment of recombinant pasteurella multocida toxin.pasteurella multocida serogroup d, producing p. multocida toxin (pmt), is a causative pathogen of progressive atrophic rhinitis (par) in swine. to evaluate the protective immunity and vaccination efficacy of the truncated form of pmt, a c-terminal form of recombinant pmt (designated pmt2.3; amino acid residues 505 to 1285 of pmt) was expressed in an escherichia coli expression system, and the humoral and cellular immune responses to pmt2.3 were investigated. pmt2.3 vaccination in mice led to hig ...201222837096
differences in health status affect susceptibility and mapping of genetic loci for atherosclerosis (fatty streak) in inbred mice.we observed differences in atherosclerosis susceptibility in mouse inbred strains over the years as the health status of our animal rooms increased. therefore, we investigated the effect of animal room health status on atherosclerosis susceptibility in different strains. as these data can also be used for genome-wide association mapping, we performed a mapping study and compared our results with previously found quantitative trait loci for atherosclerosis in mouse and humans.201222837474
spontaneous bacterial peritonitis and pneumonia caused by bordetella bronchiseptica.bordetella bronchiseptica is a rare cause of invasive human infection. the most common infection in humans is the respiratory tract infection and it is usually associated with immunosuppression, particularly acquired immunodeficiency syndrome (aids). we report a case of a pneumonia and peritonitis in a 42-year-old female with alcoholic liver disease. the patient died despite treatment with antibiotics. this case illustrates the potential virulence of b. bronchiseptica in susceptible patients and ...201222842947
skull base defect in a patient with ozena undergoing dacryocystorhinostomy.ozena, which is often used interchangeably with atrophic rhinitis or empty nose syndrome, is a progressive and chronically debilitating nasal disease that results in atrophy of the nasal mucosa, nasal crusting, fetor, and destruction of submucosal structures. although the etiology is not completely understood, infection with klebsiella ozaenae is widely believed to contribute to the destructive changes. we present a case of a patient with ozena secondary to k. ozaenae with extensive destruction ...201122852113
efficacy of intranasal administration of a modified live feline herpesvirus 1 and feline calicivirus vaccine against disease caused by bordetella bronchiseptica after experimental challenge.studies suggest that intranasal vaccination can stimulate nonspecific immunity against agents not contained within the vaccine, but this effect is not reported for cats.201622860699
phenotypic and genomic analysis of hypervirulent human-associated bordetella bronchiseptica.b. bronchiseptica infections are usually associated with wild or domesticated animals, but infrequently with humans. a recent phylogenetic analysis distinguished two distinct b. bronchiseptica subpopulations, designated complexes i and iv. complex iv isolates appear to have a bias for infecting humans; however, little is known regarding their epidemiology, virulence properties, or comparative genomics.201222863321
specific biological diagnoses are needed to determine the durability of pertussis vaccine-induced immunity. 201222871827
aroa deleted bordetella bronchiseptica inspiring robust mucosal immune response and provide full protection against intranasal challenge.bordetella bronchiseptica is a gram-negative respiratory pathogen responsible for atrophic rhinitis and bronchopneumonia in swine. several vaccines aimed at preventing b. bronchiseptica have been used, but a safe and efficient live vaccine for use in piglets remains elusive. in this study, we constructed an aroa-deleted b. bronchiseptica strain (qh0814) and evaluated its safety and protective efficiency in piglets. lung lesion scores in qh0814-immunized piglets post-challenge were significantly ...201322892249
sige facilitates the adaptation of bordetella bronchiseptica to stress conditions and lethal infection in immunocompromised mice.the cell envelope of a bacterial pathogen can be damaged by harsh conditions in the environment outside a host and by immune factors during infection. cell envelope stress responses preserve the integrity of this essential compartment and are often required for virulence. bordetella species are important respiratory pathogens that possess a large number of putative transcription factors. however, no cell envelope stress responses have been described in these species. among the putative bordetell ...201222897969
a bioinformatic strategy for the detection, classification and analysis of bacterial autotransporters.autotransporters are secreted proteins that are assembled into the outer membrane of bacterial cells. the passenger domains of autotransporters are crucial for bacterial pathogenesis, with some remaining attached to the bacterial surface while others are released by proteolysis. an enigma remains as to whether autotransporters should be considered a class of secretion system, or simply a class of substrate with peculiar requirements for their secretion. we sought to establish a sensitive search ...201222905239
comparative genomics evidence that only protein toxins are tagging bad bugs.the term toxin was introduced by roux and yersin and describes macromolecular substances that, when produced during infection or when introduced parenterally or orally, cause an impairment of physiological functions that lead to disease or to the death of the infected organism. long after the discovery of toxins, early genetic studies on bacterial virulence demonstrated that removing a certain number of genes from pathogenic bacteria decreases their capacity to infect hosts. each of the removed ...201122919573
role of escp (orf16) in injectisome biogenesis and regulation of type iii protein secretion in enteropathogenic escherichia coli.enteropathogenic escherichia coli employs a type iii secretion system (t3ss) to translocate virulence effector proteins directly into enterocyte host cells, leading to diarrheal disease. the t3ss is encoded within the chromosomal locus of enterocyte effacement (lee). the function of some of the lee-encoded proteins remains unknown. here we investigated the role of the orf16 protein in t3ss biogenesis and function. an orf16 deletion mutant showed translocator and effector protein secretion profil ...201222923600
iron and ph-responsive ftrabcd ferrous iron utilization system of bordetella species.a putative operon encoding an uncharacterized ferrous iron transport (ftrabcd) system was previously identified in cdna microarray studies. in growth studies using buffered medium at ph values ranging from ph 6.0 to 7.6, bordetella pertussis and bordetella bronchiseptica ftrabcd system mutants showed dramatic reductions in growth yields under iron-restricted conditions at ph 6.0, but had no growth defects at ph 7.6. supplementation of culture medium with 2 mm ascorbate reductant was inhibitory t ...201222924881
inhibition of protein synthesis on the ribosome by tildipirosin compared with other veterinary macrolides.tildipirosin is a 16-membered-ring macrolide developed to treat bacterial pathogens, including mannheimia haemolytica and pasteurella multocida, that cause respiratory tract infections in cattle and swine. here we evaluated the efficacy of tildipirosin at inhibiting protein synthesis on the ribosome (50% inhibitory concentration [ic(50)], 0.23 ± 0.01 μm) and compared it with the established veterinary macrolides tylosin, tilmicosin, and tulathromycin. mutation and methylation at key rrna nucleot ...201222926570
siderocalin/lcn2/ngal/24p3 does not drive apoptosis through gentisic acid mediated iron withdrawal in hematopoietic cell lines.siderocalin (also lipocalin 2, ngal or 24p3) binds iron as complexes with specific siderophores, which are low molecular weight, ferric ion-specific chelators. in innate immunity, siderocalin slows the growth of infecting bacteria by sequestering bacterial ferric siderophores. siderocalin also binds simple catechols, which can serve as siderophores in the damaged urinary tract. siderocalin has also been proposed to alter cellular iron trafficking, for instance, driving apoptosis through iron eff ...201222928018
susceptibility of canine and feline bacterial pathogens to pradofloxacin and comparison with other fluoroquinolones approved for companion animals.in this study, 908 bacterial pathogens from defined infections of dogs and cats were tested for their susceptibility to the novel fluoroquinolone pradofloxacin, which was approved in 2011 for use in cats and dogs. most of the bacteria tested (staphylococcus aureus, staphylococcus pseudintermedius, escherichia coli, β-haemolytic streptococci, pasteurella multocida and bordetella bronchiseptica) exhibited low pradofloxacin mic(90) values of ≤ 0.25 μg/ml. solely proteus spp. and pseudomonas aerugin ...201322939523
out-patient antimicrobial drug use in dogs and cats for new disease events from community companion animal practices in ontario.this study investigated oral and parenteral antimicrobial use in dogs and cats, and evaluated antimicrobial use in feline upper respiratory tract disease (furtd), feline lower urinary tract disease (flutd), and canine infectious tracheobronchitis. study journals (n = 1807) were submitted by 84 veterinarians. sixty-five percent of the antimicrobials prescribed in dogs and 67% in cats were β-lactams. most frequently prescribed in dogs were cephalexin (33%) and amoxicillin-clavulanic acid (16%), an ...201222942447
surveillance cultures of samples obtained from biopsy channels and automated endoscope reprocessors after high-level disinfection of gastrointestinal endoscopes.the instrument channels of gastrointestinal (gi) endoscopes may be heavily contaminated with bacteria even after high-level disinfection (hld). the british society of gastroenterology guidelines emphasize the benefits of manually brushing endoscope channels and using automated endoscope reprocessors (aers) for disinfecting endoscopes. in this study, we aimed to assess the effectiveness of decontamination using reprocessors after hld by comparing the cultured samples obtained from biopsy channels ...201222943739
solitary restriction endonucleases in prokaryotic genomes.prokaryotic restriction-modification (r-m) systems defend the host cell from the invasion of a foreign dna. they comprise two enzymatic activities: specific dna cleavage activity and dna methylation activity preventing cleavage. typically, these activities are provided by two separate enzymes: a dna methyltransferase (mtase) and a restriction endonuclease (re). in the absence of a corresponding mtase, an re of type ii r-m system is highly toxic for the cell. genes of the r-m system are linked in ...201222965118
naxd is a deacetylase required for lipid a modification and francisella pathogenesis.modification of specific gram-negative bacterial cell envelope components, such as capsule, o-antigen and lipid a, are often essential for the successful establishment of infection. francisella species express lipid a molecules with unique characteristics involved in circumventing host defences, which significantly contribute to their virulence. in this study, we show that naxd, a member of the highly conserved ydjc superfamily, is a deacetylase required for an important modification of the oute ...201222966934
multidrug-resistance and toxic metal tolerance of medically important bacteria isolated from an aquaculture system.the use of antimicrobials and toxic metals should be considered carefully in aquaculture and surrounding environments. we aimed to evaluate medically relevant bacteria in an aquaculture system and their susceptibility to antimicrobials and toxic metals. selective cultures for enterobacteria (ent), non-fermenting gram-negative rods (nfr) and gram-positive cocci (gpc) were obtained from water samples collected in two different year seasons. the isolated bacteria were biochemically identified and a ...201222972388
optimization of matrix-assisted laser desorption ionization-time of flight mass spectrometry analysis for bacterial identification.matrix-assisted laser desorption ionization-time of flight mass spectrometry (maldi-tof ms) is a relatively new addition to the clinical microbiology laboratory. the performance of the maldi biotyper system (bruker daltonics) was compared to those of phenotypic and genotypic identification methods for 690 routine and referred clinical isolates representing 102 genera and 225 unique species. we systematically compared direct-smear and extraction methods on a taxonomically diverse collection of is ...201222993178
the effect of infection order of porcine circovirus type 2 and porcine reproductive and respiratory syndrome virus on dually infected swine alveolar macrophages.concurrent infection with porcine circovirus type 2 (pcv2) and porcine reproductive and respiratory syndrome virus (prrsv) is known as one of the major causes for porcine respiratory disease complex (prdc). dual infection with pcv2 and prrsv is consistently to have more severe clinical presentations and pulmonary lesions than infection with pcv2 alone or prrsv alone. however, it is not known if dual infections with pcv2 and prrsv in different infection order may lead to different clinical sympto ...201223009687
pr-39, a porcine host defence peptide, is prominent in mucosa and lymphatic tissue of the respiratory tract in healthy pigs and pigs infected with actinobacillus pleuropneumoniae.host defence peptides are important components of mammalian innate immunity. we have previously shown that pr-39, a cathelicidin host defence peptide, is an important factor in porcine innate immune mechanisms as a first line of defence after infection with actinobacillus pleuropneumoniae. pr-39 interacts with bacterial and mammalian cells and is involved in a variety of processes such as killing of bacteria and promotion of wound repair. in bronchoalveolar lavage fluid of infected pigs pr-39 co ...201223016650
similarity analysis, synthesis, and bioassay of antibacterial cyclic peptidomimetics.the chemical similarity of antibacterial cyclic peptides and peptidomimetics was studied in order to identify new promising cyclic scaffolds. a large descriptor space coupled with cluster analysis was employed to digitize known antibacterial structures and to gauge the potential of new peptidomimetic macrocycles, which were conveniently synthesized by acylbenzotriazole methodology. some of the synthesized compounds were tested against an array of microorganisms and showed antibacterial activity ...201223019443
the aspergillus fumigatus dihydroxyacid dehydratase ilv3a/ilvc is required for full virulence.dihydroxyacid dehydratase (dhad) is a key enzyme in the branched-chain amino acid biosynthetic pathway that exists in a variety of organisms, including fungi, plants and bacteria, but not humans. in this study we identified four putative dhad genes from the filamentous fungus aspergillus fumigatus by homology to saccharomyces cerevisiae ilv3. two of these genes, afua_2g14210 and afua_1g03550, initially designated afilv3a and afilv3b for this study, clustered in the same group as s. cerevisiae il ...201223028460
small mutations in bordetella pertussis are associated with selective sweeps.bordetella pertussis is the causative agent of pertussis, a highly contagious disease of the human respiratory tract. despite high vaccination coverage, pertussis has resurged and has become one of the most prevalent vaccine-preventable diseases in developed countries. we have proposed that both waning immunity and pathogen adaptation have contributed to the persistence and resurgence of pertussis. allelic variation has been found in virulence-associated genes coding for the pertussis toxin a su ...201223029513
adaptive and mutational resistance: role of porins and efflux pumps in drug resistance.the substantial use of antibiotics in the clinic, combined with a dearth of new antibiotic classes, has led to a gradual increase in the resistance of bacterial pathogens to these compounds. among the various mechanisms by which bacteria endure the action of antibiotics, those affecting influx and efflux are of particular importance, as they limit the interaction of the drug with its intracellular targets and, consequently, its deleterious effects on the cell. this review evaluates the impact of ...201223034325
effects of a diet high in salt, fat, and sugar on telemetric blood pressure measurements in conscious, unrestrained adult yucatan miniature swine (sus scrofa).radiotelemetry was used to evaluate diet-related elevation of blood pressure in adult yucatan miniature swine. systolic arterial blood pressure (sap), diastolic atrial blood pressure (dap), heart rate, and locomotor activity were assessed in 9- or 11-mo-old yucatan miniature pigs fed a standard diet or a north american-type diet high in salt, fat, and sugar (hsfs). compared with pigs fed standard diet, pigs fed hsfs diet showed markedly elevated sap (132 ± 3 compared with 156 ± 6 mm hg), whereas ...201223043781
variation in airway responsiveness of male c57bl/6 mice from 5 vendors.mice are now the most commonly used animal model for the study of asthma. the mouse asthma model has many characteristics of the human pathology, including allergic sensitization and airway hyperresponsiveness. inbred strains are commonly used to avoid variations due to genetic background, but variations due to rearing environment are not as well recognized. after a change in mouse vendors and a switch from c57bl/6j mice to c57bl/6n mice, we noted significant differences in airway responsiveness ...201223043804
comparison of pcr/electron spray ionization-time-of-flight-mass spectrometry versus traditional clinical microbiology for active surveillance of organisms contaminating high-use surfaces in a burn intensive care unit, an orthopedic ward and healthcare workers.understanding nosocomial pathogen transmission is restricted by culture limitations. novel platforms, such as pcr-based electron spray ionization-time-of-flight-mass spectrometry (esi-tof-ms), may be useful as investigational tools.201223050585
a type vi secretion system encoding locus is required for bordetella bronchiseptica immunomodulation and persistence in vivo.type vi secretion systems (t6sss) have been identified in numerous gram-negative pathogens, but the lack of a natural host infection model has limited analysis of t6ss contributions to infection and pathogenesis. here, we describe disruption of a gene within locus encoding a putative t6ss in bordetella bronchiseptica strain rb50, a respiratory pathogen that circulates in a broad range of mammals, including humans, domestic animals, and mice. the 26 gene locus encoding the b. bronchiseptica t6ss ...201223071529
developing insights into the mechanisms of evolution of bacterial pathogens from whole-genome sequences.evolution of bacterial pathogen populations has been detected in a variety of ways including phenotypic tests, such as metabolic activity, reaction to antisera and drug resistance and genotypic tests that measure variation in chromosome structure, repetitive loci and individual gene sequences. while informative, these methods only capture a small subset of the total variation and, therefore, have limited resolution. advances in sequencing technologies have made it feasible to capture whole-genom ...201223075447
[bacterial susceptibility testings of the lower airways of diseased dogs].in this retrospective study over 5 years the bacterial flora of the deep airways of diseased dogs was sampled using bronchioalveolar lavage and its in-vitro susceptibility to numerous antimicrobial agents was analysed.201223076014
gapfiller: a de novo assembly approach to fill the gap within paired reads.next generation sequencing technologies are able to provide high genome coverages at a relatively low cost. however, due to limited reads' length (from 30 bp up to 200 bp), specific bioinformatics problems have become even more difficult to solve. de novo assembly with short reads, for example, is more complicated at least for two reasons: first, the overall amount of "noisy" data to cope with increased and, second, as the reads' length decreases the number of unsolvable repeats grows. our work' ...201223095524
identification of a co2 responsive regulon in bordetella.sensing the environment allows pathogenic bacteria to coordinately regulate gene expression to maximize survival within or outside of a host. here we show that bordetella species regulate virulence factor expression in response to carbon dioxide levels that mimic in vivo conditions within the respiratory tract. we found strains of bordetella bronchiseptica that did not produce adenylate cyclase toxin (act) when grown in liquid or solid media with ambient air aeration, but produced act and additi ...201223112828
identification, expression and activity analyses of five novel duck beta-defensins.in the current study, five novel avian β-defensins (avbds) were identified and characterized in tissues from peking ducks (anas platyrhynchos). the nucleotide sequences of these cdnas comprised 198 bp, 182 bp, 201 bp, 204 bp, and 168 bp, and encoded 65, 60, 66, 67, and 55 amino acids, respectively. homology, characterization and comparison of these genes with avbd from other avian species confirmed that they were apl_avbd1, 3, 5, 6, and 16. recombinant avbds were produced and purified by express ...201223112840
electrocardiograms corresponding to the development of myocardial infarction in anesthetized whhlmi rabbits (oryctolagus cuniculus), an animal model for familial hypercholesterolemia.the aim of this study was to determine whether features indicative of myocardial ischemia occur in the electrocardiograms (ecg) in myocardial infarction-prone watanabe heritable hyperlipidemic (whhlmi) rabbits, an animal model for human familial hypercholesterolemia. ecg were recorded in 110 anesthetized whhlmi rabbits (age, 10 to 39 mo) by using unipolar and bipolar limb leads with or without chest leads. we noted the following electrocardiographic changes: t wave inversion (37.4%), st segment ...201223114045
synthase-dependent exopolysaccharide secretion in gram-negative bacteria.the biosynthesis and export of bacterial cell-surface polysaccharides is known to occur through several distinct mechanisms. recent advances in the biochemistry and structural biology of several proteins in synthase-dependent polysaccharide secretion systems have identified key conserved components of this pathway in gram-negative bacteria. these components include an inner-membrane-embedded polysaccharide synthase, a periplasmic tetratricopeptide repeat (tpr)-containing scaffold protein, and an ...201223117123
synthase-dependent exopolysaccharide secretion in gram-negative bacteria.the biosynthesis and export of bacterial cell-surface polysaccharides is known to occur through several distinct mechanisms. recent advances in the biochemistry and structural biology of several proteins in synthase-dependent polysaccharide secretion systems have identified key conserved components of this pathway in gram-negative bacteria. these components include an inner-membrane-embedded polysaccharide synthase, a periplasmic tetratricopeptide repeat (tpr)-containing scaffold protein, and an ...201223117123
transcriptome profiling reveals stage-specific production and requirement of flagella during biofilm development in bordetella bronchiseptica.we have used microarray analysis to study the transcriptome of the bacterial pathogen bordetella bronchiseptica over the course of five time points representing distinct stages of biofilm development. the results suggest that b. bronchiseptica undergoes a coordinately regulated gene expression program similar to a bacterial developmental process. expression and subsequent production of the genes encoding flagella, a classical bvg(-) phase phenotype, occurs and is under tight regulatory control d ...201223152870
the response regulator sype controls biofilm formation and colonization through phosphorylation of the syp-encoded regulator sypa in vibrio fischeri.bacteria utilize multiple regulatory systems to modulate gene expression in response to environmental changes, including two-component signalling systems and partner-switching networks. we recently identified a novel regulatory protein, sype, that combines features of both signalling systems. sype contains a central response regulator receiver domain flanked by putative kinase and phosphatase effector domains with similarity to partner-switching proteins. sype was previously shown to exert dual ...201223171087
the response regulator sype controls biofilm formation and colonization through phosphorylation of the syp-encoded regulator sypa in vibrio fischeri.bacteria utilize multiple regulatory systems to modulate gene expression in response to environmental changes, including two-component signalling systems and partner-switching networks. we recently identified a novel regulatory protein, sype, that combines features of both signalling systems. sype contains a central response regulator receiver domain flanked by putative kinase and phosphatase effector domains with similarity to partner-switching proteins. sype was previously shown to exert dual ...201223171087
a novel tetravalent leptospira bacterin protects against infection and shedding following challenge in dogs.recent evidence based on the current epidemiological situation suggests that vaccines against canine leptospirosis in europe should be directed against infection with leptospira interrogans (sensu lato) serogroups canicola, icterohaemorrhagiae, grippotyphosa and australis. in the eight studies presented here, dogs were vaccinated with nobivac l4 (msd animal health), a new tetravalent inactivated vaccine containing antigen from four strains representing these four serogroups. the dogs were then c ...201223180149
a novel tetravalent leptospira bacterin protects against infection and shedding following challenge in dogs.recent evidence based on the current epidemiological situation suggests that vaccines against canine leptospirosis in europe should be directed against infection with leptospira interrogans (sensu lato) serogroups canicola, icterohaemorrhagiae, grippotyphosa and australis. in the eight studies presented here, dogs were vaccinated with nobivac l4 (msd animal health), a new tetravalent inactivated vaccine containing antigen from four strains representing these four serogroups. the dogs were then c ...201223180149
the standard european vector architecture (seva): a coherent platform for the analysis and deployment of complex prokaryotic phenotypes.the 'standard european vector architecture' database (seva-db, http://seva.cnb.csic.es) was conceived as a user-friendly, web-based resource and a material clone repository to assist in the choice of optimal plasmid vectors for de-constructing and re-constructing complex prokaryotic phenotypes. the seva-db adopts simple design concepts that facilitate the swapping of functional modules and the extension of genome engineering options to microorganisms beyond typical laboratory strains. under the ...201223180763
the standard european vector architecture (seva): a coherent platform for the analysis and deployment of complex prokaryotic phenotypes.the 'standard european vector architecture' database (seva-db, http://seva.cnb.csic.es) was conceived as a user-friendly, web-based resource and a material clone repository to assist in the choice of optimal plasmid vectors for de-constructing and re-constructing complex prokaryotic phenotypes. the seva-db adopts simple design concepts that facilitate the swapping of functional modules and the extension of genome engineering options to microorganisms beyond typical laboratory strains. under the ...201223180763
tgpa, a protein with a eukaryotic-like transglutaminase domain, plays a critical role in the viability of pseudomonas aeruginosa.the gram-negative bacterium pseudomonas aeruginosa is an important opportunistic pathogen in compromised individuals, such as patients with cystic fibrosis, severe burns or impaired immunity. in this work we aimed to screen novel essential genes of p. aeruginosa by shotgun antisense identification, a technique that was developed a decade ago for the gram-positive bacterium staphylococcus aureus and was under-used in gram-negative bacteria for a considerable period of time. following antisense sc ...201223209712
generating super-shedders: co-infection increases bacterial load and egg production of a gastrointestinal helminth.co-infection by multiple parasites is common within individuals. interactions between co-infecting parasites include resource competition, direct competition and immune-mediated interactions and each are likely to alter the dynamics of single parasites. we posit that co-infection is a driver of variation in parasite establishment and growth, ultimately altering the production of parasite transmission stages. to test this hypothesis, three different treatment groups of laboratory mice were infect ...201323256186
design and application of chitosan microspheres as oral and nasal vaccine carriers: an updated review.chitosan, a natural biodegradable polymer, is of great interest in biomedical research due to its excellent properties including bioavailability, nontoxicity, high charge density, and mucoadhesivity, which creates immense potential for various pharmaceutical applications. it has gelling properties when it interacts with counterions such as sulfates or polyphosphates and when it crosslinks with glutaraldehyde. this characteristic facilitates its usefulness in the coating or entrapment of biochemi ...201223271909
immunoprophylactic effects of shiitake mushroom (lentinula edodes) against bordetella bronchiseptica in mice.antimicrobials are used as feed additives to improve growth performance and to prevent subclinical disease challenge in industrial animals. however, these drugs can lead to the development of resistant strains of bacteria. shiitake mushrooms (sm) (lentinula edodes) have long been popular as a health food in east asia. moreover, sm-derived polysaccharides are well-known as immunostimulants that possess antimicrobial properties. the aim of the present study was to evaluate the immunoprophylactic e ...201223274987
optimized protocol for multiplex nested polymerase chain reaction to detect and differentiate haemophilus parasuis, streptococcus suis, and mycoplasma hyorhinis in formalin-fixed, paraffin-embedded tissues from pigs with polyserositis.an optimized protocol was developed for the simultaneous detection and differentiation of haemophilus parasuis, streptococcus suis, and mycoplasma hyorhinis in formalin-fixed, paraffin-embedded (ffpe) tissues with multiplex nested polymerase chain reaction (pcr). this method also determines the prevalence of these bacteria in pigs with polyserositis. dna extraction with a combination of a commercial reagent and proteinase k resulted in more frequent detection of the pathogens than dna extraction ...201223277698
flagella from five cronobacter species induce pro-inflammatory cytokines in macrophage derivatives from human monocytes.cronobacter spp. are opportunistic pathogens linked to lie-threatening infections in neonates and contaminated powdered infant formula that has been epidemiologically associated with these cases. clinical symptoms of cronobacter include necrotizing enterocolitis, bacteremia, and meningitis. flagella from c. sakazakii are involved in biofilm formation and its adhesion to epithelial cells. we investigated the role of flagella from c. sakazakii st1 and st4, c. malonaticus, c. muytjensii, c. turicen ...201223284883
resistance of sprague-dawley rats to infection with helicobacter pullorum.helicobacter pullorum is an enterohepatic helicobacter spp. known to infect both chickens and humans. h. pullorum infection has recently been reported in both mice and rats. this study was designed to determine whether standard methods of colony health surveillance using exposure to rodent soiled bedding could detect h. pullorum in sprague-dawley rats. we exposed 8 helicobacter-free sprague-dawley rats to bedding from h. pullorum-infected brown norway rats. fecal samples were analyzed by pcr eve ...201223294887
bacterial urease and its role in long-lasting human diseases.urease is a virulence factor found in various pathogenic bacteria. it is essential in colonization of a host organism and in maintenance of bacterial cells in tissues. due to its enzymatic activity, urease has a toxic effect on human cells. the presence of ureolytic activity is an important marker of a number of bacterial infections. urease is also an immunogenic protein and is recognized by antibodies present in human sera. the presence of such antibodies is connected with progress of several l ...201223305365
handling of adolescent rats improves learning and memory and decreases anxiety.some environmental interventions can result in physiologic and behavioral changes in laboratory animals. in this context, the handling of adolescent or adult rodents has been reported to influence exploratory behavior and emotionality. here we examined the effects of handling on memory and anxiety levels of adolescent rats. male sprague-dawley rats (age, 60 d) were divided into a control group and a handled group, which were handled for 5 min daily, 5 d per week, for 6 wk. during handling bouts, ...201223312082
artifactual changes in sprague-dawley rat hematologic parameters after storage of samples at 3 °c and 21 °c.circumstances can occur that prevent timely analysis of blood samples. the purpose of this study was to characterize artifactual changes in rat hematologic parameters after storage of samples at 3 and 21 °c and to document the effects of storage on peripheral blood smear findings. edta-treated blood samples were collected from 12 male sprague-dawley rats. samples were analyzed on an impedance hematology analyzer within 5 min after collection and then at 6, 24, 48, and 72 h after storage at 3 °c ...201223312091
modulation of systemic immune responses through commensal gastrointestinal microbiota.colonization of the gastrointestinal (gi) tract is initiated during birth and continually seeded from the individual's environment. gastrointestinal microorganisms play a central role in developing and modulating host immune responses and have been the subject of investigation over the last decades. animal studies have demonstrated the impact of gi tract microbiota on local gastrointestinal immune responses; however, the full spectrum of action of early gastrointestinal tract stimulation and sub ...201323326551
a genetic approach to the development of new therapeutic phages to fight pseudomonas aeruginosa in wound infections.pseudomonas aeruginosa is a frequent participant in wound infections. emergence of multiple antibiotic resistant strains has created significant problems in the treatment of infected wounds. phage therapy (pt) has been proposed as a possible alternative approach. infected wounds are the perfect place for pt applications, since the basic condition for pt is ensured; namely, the direct contact of bacteria and their viruses. plenty of virulent ("lytic") and temperate ("lysogenic") bacteriophages ar ...201223344559
a genetic approach to the development of new therapeutic phages to fight pseudomonas aeruginosa in wound infections.pseudomonas aeruginosa is a frequent participant in wound infections. emergence of multiple antibiotic resistant strains has created significant problems in the treatment of infected wounds. phage therapy (pt) has been proposed as a possible alternative approach. infected wounds are the perfect place for pt applications, since the basic condition for pt is ensured; namely, the direct contact of bacteria and their viruses. plenty of virulent ("lytic") and temperate ("lysogenic") bacteriophages ar ...201223344559
bordetella holmesii, an emerging cause of septic arthritis.bordetella holmesii is a well-described pathogen in asplenic and immunocompromised patients. here we report the first two published cases of septic arthritis caused by b. holmesii documented in apparently immunocompetent patients and unaccompanied by bacteremia.201323345301
interspecies interaction between pseudomonas aeruginosa and other microorganisms.microbes interact with each other in multicellular communities and this interaction enables certain microorganisms to survive in various environments. pseudomonas aeruginosa is a highly adaptable bacterium that ubiquitously inhabits diverse environments including soil, marine habitats, plants and animals. behind this adaptivity, p. aeruginosa has abilities not only to outcompete others but also to communicate with each other to develop a multispecies community. in this review, we focus on how p. ...201323363620
an improved recombination-based in vivo expression technology-like reporter system reveals differential cyaa gene activation in bordetella species.bordetella pertussis and bordetella bronchiseptica rely on the global two-component regulatory system bvgas to control expression of distinct phenotypic phases. in the bvg(-) phase, expression of vrg genes, including those required for motility in b. bronchiseptica, is activated and genes encoding virulence factors are not expressed. conversely, in the bvg(+) phase, genes encoding virulence factors are highly expressed while genes necessary for motility are repressed. although several genetic an ...201323381998
neisseria infection of rhesus macaques as a model to study colonization, transmission, persistence, and horizontal gene transfer.the strict tropism of many pathogens for man hampers the development of animal models that recapitulate important microbe-host interactions. we developed a rhesus macaque model for studying neisseria-host interactions using neisseria species indigenous to the animal. we report that neisseria are common inhabitants of the rhesus macaque. neisseria isolated from the rhesus macaque recolonize animals after laboratory passage, persist in the animals for at least 72 d, and are transmitted between ani ...201323382234
characterization of the n-terminal domain of btea: a bordetella type iii secreted cytotoxic effector.btea, a 69-kda cytotoxic protein, is a type iii secretion system (t3ss) effector in the classical bordetella, the etiological agents of pertussis and related mammalian respiratory diseases. currently there is limited information regarding the structure of btea or its subdomains, and no insight as to the identity of its eukaryotic partners(s) and their modes of interaction with btea. the mechanisms that lead to btea dependent cell death also remain elusive. the n-terminal domain of btea is multif ...201323383256
bis-(3'-5')-cyclic dimeric gmp regulates antimicrobial peptide resistance in pseudomonas aeruginosa.bis-(3'-5')-cyclic dimeric gmp (c-di-gmp) is an intracellular second messenger that controls the lifestyles of many bacteria. a high intracellular level of c-di-gmp induces a biofilm lifestyle, whereas a low intracellular level of c-di-gmp stimulates dispersal of biofilms and promotes a planktonic lifestyle. here, we used the expression of different reporters to show that planktonic cells, biofilm cells, and cells dispersed from biofilms (dcells) had distinct intracellular c-di-gmp levels. prote ...201323403434
draft genome sequences of pseudomonas fluorescens bs2 and pusillimonas noertemannii bs8, soil bacteria that cooperate to degrade the poly-γ-d-glutamic acid anthrax capsule.a mixed culture of pseudomonas fluorescens bs2 and pusillimonas noertemannii bs8 degraded poly-γ-d-glutamic acid; when the 2 strains were cultured separately, no hydrolytic activity was apparent. here we report the draft genome sequences of both soil isolates.201323405351
protein engineering with biosynthesized libraries from bordetella bronchiseptica bacteriophage.phage display offers a powerful approach to engineer protein affinity. a naturally occurring analog to phage display, the bordetella bronchiseptica bacteriophage (bp) employs a highly variable protein termed the major tropism determinant (mtd) to recognize its dynamic host. propagation of bp provides a self-made phage library (smpl) with vast numbers of phage particles, each displaying a single mtd variant. we report applying the diversity of the bp-smpl to access a tyrosine-rich library of mtd ...201323409008
discovery and characterization of a highly efficient enantioselective mandelonitrile hydrolase from burkholderia cenocepacia j2315 by phylogeny-based enzymatic substrate specificity prediction.a nitrilase-mediated pathway has significant advantages in the production of optically pure (r)-(-)-mandelic acid. however, unwanted byproduct, low enantioselectivity, and specific activity reduce its value in practical applications. an ideal nitrilase that can efficiently hydrolyze mandelonitrile to optically pure (r)-(-)-mandelic acid without the unwanted byproduct is needed.201323414071
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