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[construction of immune library of murine immunoglobulin genes and screening of single-chain fv-antibodies specific to diphtheria toxin b subunit].the aim of this work was to obtain the panel of recombinant single-chain fv-antibodies against diphtheria toxin b subunit, the main diagnostic and pathogenic antigen of corynebacterium diphtheriae. for this purpose we have constructed the immune library of murine immunoglobulin genes. a number of scfv specific to diphtheria toxin b subunit were acquired from the obtained library after one round of selection by phage-display. scfv encoding dna-fragments of eight clones were subcloned into plasmid ...200919873879
[immunochromatographic and latex-agglutination systems for diphtheria toxin detection].the use of two monoclonal antibody types specific to different epitopes of diphtheria toxin systems have been developed to reveal diphtheria corynebacteria toxigenicity rapidly based on immunochromatographic and latex-agglutination detection of the diphtheria toxin. the methods have been tested on a sample of 36 clinical isolates. the possibility of significant detection of the toxigenic properties of the corynebacterium strain, grown for 1 day, has been demonstrated. the developed methods allow ...200919928056
reconstitution experiments and gene deletions reveal the existence of two-component major cell wall channels in the genus corynebacterium.two small polypeptides, pora and porh, are known to form cell wall channels in corynebacterium glutamicum and in corynebacterium efficiens. the genes coding for both polypeptides are localized in close proximity to one another between the genes coding for groel2 and a polyphosphate kinase (pkk2). in this study, we investigated the relationship of pora and porh to one another. the results suggested that the major cell wall channels of corynebacterium glutamicum, corynebacterium efficiens, and cor ...201019966008
sick as a dog. 201020113976
identification and functional characterization of the nanh extracellular sialidase from corynebacterium diphtheriae.corynebacterium diphtheriae, a pathogenic gram-positive bacterium, contains sialic acids on its cell surface, but no genes related to sialic acid decoration or metabolism have been reported in c. diphtheriae. in the present study, we have identified a putative sialidase gene, nanh, from c. diphtheriae kctc3075 and characterized its product for enzyme activity. interestingly, the recombinant nanh protein was secreted as a catalytically active sialidase into the periplasmic space in escherichia co ...201020007980
diphtheria toxin igg levels in military and civilian blood donors in rio de janeiro, brazil.serologic data on diseases that are preventable by vaccines are necessary to evaluate the success of immunization programs and to identify susceptible subgroups. in the present study, we determined serum igg levels against diphtheria toxin of military and civilian blood donors (n = 75; 69.3% males and 30.7% females) aged 18-64 years, from the brazilian army biology institute, rio de janeiro, using a commercial diphtheria kit (diphtheria igg elisa; ibl, germany). most (63%) unprotected military d ...201020027481
corynebacterium diphtheriae invasion-associated protein (dip1281) is involved in cell surface organization, adhesion and internalization in epithelial cells.corynebacterium diphtheriae, the causative agent of diphtheria, is well-investigated in respect to toxin production, while little is known about c. diphtheriae factors crucial for colonization of the host. in this study, we investigated the function of surface-associated protein dip1281, previously annotated as hypothetical invasion-associated protein.201020051108
non-opsonic phagocytosis of homologous non-toxigenic and toxigenic corynebacterium diphtheriae strains by human u-937 macrophages.as interactions between bacteria and macrophages dictate the outcome of most infectious diseases, analyses of molecular mechanisms of non-opsonic phagocytosis should lead to new approaches for the prevention of diphtheria and systemic corynebacterium diphtheriae infections. the present study aimed to evaluate human macrophage-bacteria interactions in the absence of opsonin antibodies and the influence of the tox gene on this process. homologous c. diphtheriae tox+ and tox- strains were evaluated ...201020055937
expression and purification of the immunogenically active fragment b of the park williams 8 corynebacterium diphtheriae strain toxin.the construction of a hexahistidine-tagged version of the b fragment of diphtheria toxin (dtb) represents an important step in the study of the biological properties of dtb because it will permit the production of pure recombinant dtb (rdtb) in less time and with higher yields than currently available. in the present study, the genomic dna of the corynebacterium diphtheriae park williams 8 (pw8) vaccine strain was used as a template for pcr amplification of the dtb gene. after amplification, the ...201020490433
novel corynebacterium diphtheriae in domestic cats.novel nontoxigenic corynebacterium diphtheriae was isolated from a domestic cat with severe otitis. contact investigation and carrier study of human and animal contacts yielded 3 additional, identical isolates from cats, although no evidence of zoonotic transmission was identified. molecular methods distinguished the feline isolates from known c. diphtheriae.201020350389
investigations and control measures following a non-travel-associated case of toxigenic cornyebacterium diphtheriae, london, united kingdom, december 2009-january 2010.this article reports the investigation and control measures undertaken following the identification of a toxigenic strain of cornyebacterium diphtheriae var gravis, designated ribotype minsk , in a partially vaccinated teenager born in the united kingdom with no recent history of travel or known contact with a case of diphtheria or a carrier. this case highlights the need for ongoing work to improve vaccine uptake rates to ensure children receive all scheduled vaccinations.201020430002
[surface structures of gram-positive bacteria in intercellular interaction and film formation]. 201020465012
an increase in non-toxigenic corynebacterium diphtheriae infections in poland--molecular epidemiology and antimicrobial susceptibility of strains isolated from past outbreaks and those currently circulating in poland.an increase in non-toxigenic corynebacterium diphtheriae infections--mainly invasive infections--has been observed in countries with high vaccination coverage. however, reasons for this situation are unknown. in this study we characterized and compared human clinical isolates of non-toxigenic c. diphtheriae strains isolated from infections that have occurred over recent years and c. diphtheriae strains isolated from diphtheria cases from past outbreaks in poland.201020728389
toxigenic corynebacterium ulcerans infection in a veterinary student in london, united kingdom, may 2010.we report on a case of toxigenic corynebacterium ulcerans infection in a fully immunised veterinary student, investigated in london, united kingdom, in may 2010. there was no ongoing transmission in human contacts. possible animal sources were identified.201020738991
enzymatic ring-opening mechanism of verdoheme by the heme oxygenase: a combined x-ray crystallography and qm/mm study.the least understood mechanism during heme degradation by the enzyme heme oxygenase (ho) is the third step of ring opening of verdoheme to biliverdin, a process which maintains iron homeostasis. in response to this mechanistic uncertainty, we launched a combined study of x-ray crystallography and theoretical qm/mm calculations, designed to elucidate the mechanism. the air-sensitive ferrous verdoheme complex of hmuo, a heme oxygenase from corynebacterium diphtheriae, was crystallized under anaero ...201020806922
fibrinogen binds to nontoxigenic and toxigenic corynebacterium diphtheriae strains.the production of fibrinous exudates may play an important role in determining the outcome of bacterial infection. although pseudomembrane formation is a characteristic feature of diphtheria, little is known about the fibrinogen (fbn)-binding properties of corynebacterium diphtheriae strains and the influence of the gene that codes for diphtheria toxin (tox gene) in this process. in this study we demonstrated the ability of c. diphtheriae strains to bind to fbn and to convert fbn to fibrin. bact ...201020835621
multilocus sequence typing identifies evidence for recombination and two distinct lineages of corynebacterium diphtheriae.we describe the development of a multilocus sequence typing (mlst) scheme for corynebacterium diphtheriae, the causative agent of the potentially fatal upper respiratory disease diphtheria. global changes in diphtheria epidemiology are highlighted by the recent epidemic in the former soviet union (fsu) and also by the emergence of nontoxigenic strains causing atypical disease. although numerous techniques have been developed to characterize c. diphtheriae, their use is hindered by limited portab ...201020844217
similarity of rpob gene sequences of sucrose-fermenting and non-fermenting corynebacterium diphtheriae strains.during the last decades, the majority of brazilian corynebacterium diphtheriae isolates were shown to be capable to metabolize sucrose, sometimes leading to erroneous identification as a non-diphtheric corynebacterium species. the sequencing of the polymorphic region of the rna polymerase beta subunit-encoding gene (rpob) is an important taxonomic tool for identification of corynebacteria. the present study aimed to investigate the rpob gene polymorphic features of sucrose-fermenting and non suc ...201020941542
strain-specific differences in pili formation and the interaction of corynebacterium diphtheriae with host cells.corynebacterium diphtheriae, the causative agent of diphtheria, is well-investigated in respect to toxin production, while little is known about c. diphtheriae factors crucial for colonization of the host. in this study, we investigated strain-specific differences in adhesion, invasion and intracellular survival and analyzed formation of pili in different isolates.201020942914
toxigenic corynebacterium diphtheriae isolated from a wound in a horse. 201020495169
nontoxinogenic corynebacterium diphtheriae as a rare cause of native endocarditis in childhood.we report a pediatric case of negative blood culture pulmonary valve endocarditis caused by a nontoxinogenic corynebacterium diphtheriae biotype gravis and review the literature on this disease.201020495509
genome organization and pathogenicity of corynebacterium diphtheriae c7(-) and pw8 strains.corynebacterium diphtheriae is the causative agent of diphtheria. in 2003, the complete genomic nucleotide sequence of an isolate (nctc13129) from a large outbreak in the former soviet union was published, in which the presence of 13 putative pathogenicity islands (pais) was demonstrated. in contrast, earlier work on diphtheria mainly employed the c7(-) strain for genetic analysis; therefore, current knowledge of the molecular genetics of the bacterium is limited to that strain. however, genomic ...201020547743
the abc transporter hrtab confers resistance to hemin toxicity and is regulated in a hemin-dependent manner by the chras two-component system in corynebacterium diphtheriae.corynebacterium diphtheriae, the causative agent of the severe respiratory disease diphtheria, utilizes hemin and hemoglobin as iron sources for growth in iron-depleted environments. because of the toxicity of high levels of hemin and iron, these compounds are often tightly regulated in bacterial systems. in this report, we identify and characterize the c. diphtheriae hrtab genes, which encode a putative abc type transporter involved in conferring resistance to the toxic effects of hemin. deleti ...201020639324
solution 1h nmr characterization of substrate-free c. diphtheriae heme oxygenase: pertinence for determining magnetic axes in paramagnetic substrate complexes.proton 2d nmr was used to confirm in solution a highly conserved portion of the molecular structure upon substrate loss for the heme oxygenase from the pathogenic bacterium corynebacterium diphtheriae, hmuo. the chemical shifts for the conserved portion of the structure are assessed as references for the dipolar shifts needed to determine the orientation of the paramagnetic susceptibility tensor, chi, in paramagnetic substrate complexes of hmuo. it is shown that the chemical shifts for the struc ...201020655112
[inhibition of adherence of corynebacterium diphtheriae to human buccal epithelium by glycoside hydrolases from marine hydrobiontes].a possibility of adhesion inhibition of corynebacterium diphtheriae to human buccal epithelium by glycoside hydrolases of marine hydrobiontes was investigated using alpha-galactosidase from marine bacterium pseudoalteromonas sp. kmm 701, total enzyme preparation and beta-1,3-glucanase from marine fungi chaetomium, total enzyme preparation and beta-1,3-glucanase from marine mollusk littorina kurila, and total enzyme preparation from crystalline style of marine mollusk spisula sachalinensis were u ...201020695214
diphtheria in the united kingdom, 1986-2008: the increasing role of corynebacterium ulcerans.diphtheria is an uncommon disease in the uk due to an effective immunization programme; consequently when cases do arise, there can be delays in diagnosis and case-fatality rates remain high. we reviewed 102 patients with infections caused by toxigenic corynebacteria (an average of four per year) reported in the uk between 1986 and 2008: 42 corynebacterium diphtheriae, 59 c. ulcerans and one c. pseudotuberculosis, as well as 23 asymptomatic carriers. five fatalities were reported, all in unvacci ...201020696088
construction of an in vitro trans-sialylation system: surface display of corynebacterium diphtheriae sialidase on saccharomyces cerevisiae.sialidases can be used to transfer sialic acids from sialoglycans to asialoglycoconjugates via the trans-glycosylation reaction mechanism. some pathogenic bacteria decorate their surfaces with sialic acids which were often scavenged from host sialoglycoconjugates using their surface-localized enzymes. in this study, we constructed an in vitro trans-sialylation system by reconstructing the exogenous sialoglycoconjugate synthesis system of pathogens on the surfaces of yeast cells. the nanh gene en ...201020711574
[monitoring of antibodies against diphtheria, tetanus and pertussis in pregnant women].to assess antibody levels against diphtheria, pertussis, and tetanus in pregnant women.201020218342
[assessment of different regimens of diphtheria serotherapy].efficacy of different treatment regimens with equine diphtheria antitoxin (eda) was assessed on clinical samples as well as in experiments on animals.201020218350
dangerous horseplay. 201021029983
native valve endocarditis caused by a non-toxigenic strain of corynebacterium diphtheriae. 201021045480
[normal conjunctival flora in healthy infants aged from 1 to 4 months].to investigate the normal conjunctival bacterial flora isolated from healthy infants aged from 1 to 4 months and to analyze its correlated factors.201021055200
regulation of genes involved in sugar uptake, glycolysis and lactate production in corynebacterium glutamicum.corynebacterium glutamicum is a nonpathogenic, gc-rich, gram-positive bacterium with a long history in the industrial production of amino acids. recently, the species has become of increasing interest as a model bacterium for closely related, medically important pathogenic species such as corynebacterium diphtheriae and mycobacterium tuberculosis. in this article, recent advances in understanding of the c. glutamicum regulatory network of genes involved in carbohydrate metabolism are reviewed wi ...201021073308
immunogenicity and reactogenicity of a combined fully liquid dtpw-hepb-hib pentavalent vaccine in healthy infants: no clinically relevant impact of a birth dose of hepatitis b vaccine.in this open-label, non-randomized phase ii study, the safety and immunogenicity of a fully liquid diphtheria-tetanus-whole cell pertussis-hepatitis b-haemophilus influenzae type b (dtpw-hepb-hib) combination vaccine (quinvaxem(®)) were assessed in infants who had or had not received a birth dose of hepatitis b (hepb) vaccine.201021093342
identification of corynebacterium diphtheriae gene involved in adherence to epithelial cells.corynebacterium diphtheriae the causative pathogen of human diphtheria infects the nasopharynx or skin. although diphtheria has been extensively studied, little is known about the two key aspects of c. diphtheriae invasiveness: colonization and invasion. the role of adhesive properties in establishing the infection of c. diphtheriae strains, independent of toxin production, still needs to be clarified. in this study, we describe a novel gene involved in adherence to epithelial cells. transformat ...201021111065
persistence of nontoxigenic corynebacterium diphtheriae biotype gravis strains in pondicherry, southern india. 201021159931
defense and death responses to pore forming toxins.pore forming toxins (pft) are important virulence factors produced by bacteria to kill eukaryotic cells by forming holes in the cellular membrane. they represent a diverse group of proteins with a wide range of target cells. although the amino acid sequence is not conserved among the different pft, many of them share some aspects of their mechanism of action. in general, the mode of action of pft involves receptor recognition, activation by proteases, and aggregation into oligomeric-structures t ...201021415876
oral immunogenicity of tomato-derived sdpt polypeptide containing corynebacterium diphtheriae, bordetella pertussis and clostridium tetani exotoxin epitopes.dpt vaccine, designed to immunize against diphtheria, pertussis, and tetanus, has been shown to be effective in humans. nevertheless, dissatisfaction with the whole-cell preparations is due to the reactogenicity, which has to lead to the development of new safer formulations. previously, we described the expression in tomato of a plant-optimized synthetic gene encoding the recombinant polypeptide sdpt, containing mainly immunoprotective epitopes of the diphtheria, pertussis and tetanus exotoxins ...201021188384
molecular characterization and therapeutic potential of a marine bacterium pseudoalteromonas sp. kmm 701 alpha-galactosidase.an alpha-galactosidase capable of converting b red blood cells into the universal blood type cells at the neutral ph was produced by a novel obligate marine bacterium strain kmm 701 (vkm b-2135 d). the organism is heterotrophic, aerobic, and halophilic and requires na+ ions and temperature up to 34 degrees c for its growth. the strain has a unique combination of polysaccharide-degrading enzymes. its single intracellular alpha-galactosidase exceeded other glycoside hydrolases in the level of expr ...201019629597
conservation of structure and protein-protein interactions mediated by the secreted mycobacterial proteins esxa, esxb, and espa.mycobacterium tuberculosis esxa and esxb proteins are founding members of the wxg100 (wxg) protein family, characterized by their small size (approximately 100 amino acids) and conserved wxg amino acid motif. m. tuberculosis contains 11 tandem pairs of wxg genes; each gene pair is thought to be coexpressed to form a heterodimer. the precise role of these proteins in the biology of m. tuberculosis is unknown, but several of the heterodimers are secreted, which is important for virulence. however, ...201019854905
cell surface display of minor pilin adhesins in the form of a simple heterodimeric assembly in corynebacterium diphtheriae.pilus assembly in gram-positive bacteria occurs by a two-step mechanism, whereby pilins are polymerized and then covalently anchored to the cell wall. in corynebacterium diphtheriae, the pilin-specific sortase srta catalyses polymerization of the spaa-type pilus, consisting of the shaft pilin spaa, tip pilin spac and minor pilin spab. cell wall anchoring of the spaa polymers is triggered when srta incorporates spab into the pilus base via lysine-mediated transpeptidation; anchoring to the cell w ...201121205008
recent cases of non-toxigenic corynebacterium diphtheriae in scotland: justification for continued surveillance. 201121212144
what can molecular modelling bring to the design of artificial inorganic cofactors?in recent years, the development of synthetic metalloenzymes based on the insertion of inorganic catalysts into biological macromolecules has become a vivid field of investigation. the success of the design of these composites is highly dependent on an atomic understanding of the recognition process between inorganic and biological entities. despite facing several challenging complexities, molecular modelling techniques could be particularly useful in providing such knowledge. this study aims to ...201121322482
bioactive 4-hydroxycinnamide and bioactivities of polyalthia cerasoides.constituents from polyalthia cerasoides, stem bark methanol extract, were previously documented. this study reports the first isolation of bioactive n-(4-hydroxy-β-phenethyl)-4-hydroxycinnamide (1) from ethyl acetate extract of the plant species including stigmasterol and a mixture of triterpenes from hexane and dichloromethane extracts. trace essential elements were found in the hexane extract in ppm level. the plant extracts were evaluated for their antimicrobial and antioxidative activities. ...201127857661
Canada's first case of a multidrug-resistant Corynebacterium diphtheriae strain, isolated from a skin abscess.A toxigenic Corynebacterium diphtheriae biovar mitis sequence type 136 (ST136) strain was recovered from a toe infection of an unvaccinated patient recently returned from India. The isolate was resistant to clindamycin, erythromycin (ermX positive), tetracycline, and trimethoprim-sulfamethoxazole, intermediate to ceftriaxone and cefotaxime, and had high MICs for telithromycin and chloramphenicol but was sensitive to other drugs.201121880960
Prevalence of Corynebacterium ulcerans in dogs residing in Osaka, Japan.Diphtheria-like human illness caused by Corynebacterium ulcerans is an emerging threat in developed countries, with incidence sometimes higher than that of diphtheria caused by Corynebacterium diphtheriae. Companion animals are considered a potential source of human infections. In order to determine the prevalence of C. ulcerans among dogs, we performed a screening for the bacterium in 583 dogs in the custody of the Osaka Prefectural government. Forty-four dogs (7.5%) were positive for the bacte ...201121921111
Characterization of Corynebacterium diphtheriae isolates from infected skin lesions in the Northern Territory of Australia.Corynebacterium diphtheriae is commonly isolated from cutaneous skin lesions in the Northern Territory of Australia. We prospectively assessed 32 recent isolates from infected skin lesions, in addition to reviewing 192 isolates collected over 5 years for toxin status. No isolates carried the toxin gene. Toxigenic C. diphtheriae is now a rare occurrence in the Northern Territory.201121918025
antimicrobial drug resistance in corynebacterium diphtheriae mitis. 201122099107
detection of ascitic fluid infections in patients with liver cirrhosis and ascites.ascitic fluid infections (afis) are the frequent complications of advanced liver disease. bacterial translocation is considered a key step in the pathogenesis of gut-derived bacterial infections; mainly spontaneous bacterial peritonitis (sbp) in cirrhotic patients. bacterial dna (bactdna) in ascitic fluid and serum has been suggested as a surrogate marker for bacterial translocation. we attempted at the isolation and identification of bacteria in ascitic fluid in cirrhotic patients and the asses ...201121429450
a novel comparative genomics analysis for common drug and vaccine targets in corynebacterium pseudotuberculosis and other cmn group of human pathogens.caseous lymphadenitis is a chronic goat and sheep disease caused by corynebacterium pseudotuberculosis (cp) that accounts for a huge economic loss worldwide. proper vaccination or medication is not available because of the lack of understanding of molecular biology of the pathogen. in a recent approach, four cp (cpfrc41, cp1002, cpc231, and cpi-19) genomes were sequenced to elucidate the molecular pathology of the bacteria. in this study, using these four genome sequences along with other eight ...201121443692
cutaneous diphtheria in the urban poor population of vancouver, british columbia: a 10-year review.between 1998 - 2007, records from 33 patients with cutaneous diphtheria from vancouver's inner-city were reviewed. cases were associated with injection drug use and poverty. co-infections with staphylococcus aureus, streptococcus pyogenes and arcanobacterium haemolyticum occurred. corynebacterium diphtheriae is endemic in vancouver's urban core, with mlst sequence type 76 strains predominating.201121525220
an alternative method for purifying and detoxifying diphtheria toxin.infections caused by corynebacterium diphtheriae frequently induce situations in which very small doses of antigens injected intradermally can cause strong inflammatory reactions. this bacterium secretes the diphtheria toxin (dt), a virulence factor that can be lethal to the human organism at doses below 0.1 μg/kg of body weight. the present work proposes alternative methods of dt purification using affinity chromatography and of dt detoxification through conjugating with the polymer methoxypoly ...201121549738
adhesion by pathogenic corynebacteria.pathogenic members of the genus corynebacterium cause a wide range of serious infections in humans including diphtheria. adhesion to host cells is a crucial step during infection. in corynebacterium diphtheriae, adhesion is mediated primarily by filamentous structures called pili or fimbriae that are covalently attached to the bacterial cell wall. c. diphtheriae produces three distinct pilus structures, spaa-, spad- and spah-type pili. similar to other types, the prototype spaa pilus consists of ...201121557059
rapid detection and molecular differentiation of toxigenic corynebacterium diphtheriae and corynebacterium ulcerans strains by lightcycler pcr.the systemic symptoms of diphtheria are caused by the tox-encoded diphtheria toxin (dt) which is produced by toxigenic corynebacterium spp. besides the classical agent c. diphtheriae, the zoonotic pathogen c. ulcerans has increasingly been reported as an emerging pathogen for diphtheria. the reliable detection of toxigenic corynebacterium spp. is substantial for both diphtheria surveillance in the public health sector and the clinical work-up of a patient with diphtheria-like symptoms. since the ...201121593261
diphtheria in the south of france, march 2011. 201121596008
[micro technologies in express diagnostics of toxigenic corynebacterium diphtheriae strains].development of micro technologies based approach for express diagnostics of toxigenic c. diphtheriae strains.201121598618
improved specificity of a multiplex immunoassay for the quantitation of anti-diphtheria toxin antibodies with the use of diphtheria toxoid.a non-specific binding of antibodies to diphtheria toxin, especially in adult serum samples, was observed in our diphtheria-tetanus-pertussis multiplex immunoassay (dtap4 mia). this could be significantly reduced by the use of diphtheria toxoid, achieving a good correlation with the vero cell neutralization test and the toxin binding inhibition assay.201121613460
corynebacterium diphtheriae endocarditis: a case series and review of the treatment approach.objectives: infective endocarditis due to non-toxigenic corynebacterium diphtheriae is uncommon; we report 10 cases occurring over a 14-year period in auckland, new zealand and review the approach for treatment. case series: eight of the 10 patients had known prosthetic valves or homografts in situ. three patients required surgical intervention for infective endocarditis. seven patients were treated with a combination of β-lactam and aminoglycoside, and one each was treated with a combination of ...201121641260
multilocus sequence types of invasive corynebacterium diphtheriae isolated in the rio de janeiro urban area, brazil.summaryinvasive infections caused by corynebacterium diphtheriae in vaccinated and non-vaccinated individuals have been reported increasingly. in this study we used multilocus sequence typing (mlst) to study genetic relationships between six invasive strains of this bacterium isolated solely in the urban area of rio de janeiro, brazil, during a 10-year period. of note, all the strains rendered negative results in pcr reactions for the tox gene, and four strains presented an atypical sucrose-ferm ...201121669023
novel hemin binding domains in the corynebacterium diphtheriae htaa protein interact with hemoglobin and are critical for heme-iron utilization by htaa.the human pathogen corynebacterium diphtheriae utilizes hemin and hemoglobin as iron sources for growth in iron depleted environments. the use of hemin-iron in c. diphtheriae involves the dtxr- and iron-regulated hmu hemin uptake locus, which encodes an abc hemin transporter, and the surface anchored hemin binding proteins htaa and htab. sequence analysis of htaa and htab identified a conserved region of approximately 150 amino acids that is duplicated in htaa and present in single copy in htab. ...201121803991
pathogenic bacteria in sewage treatment plants as revealed by 454 pyrosequencing.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 a ...201121780772
strain-dependent arthritogenic potential of the zoonotic pathogen corynebacterium ulcerans.during the last decade the majority of diphtheria cases in europe had corynebacterium ulcerans as the etiologic agent with dogs and cats as the reservoir hosts. however, little has been documented about the virulence factors of this zoonotic pathogen. to set up an in vivo experimental c. ulcerans infection model, conventional swiss webster mice were intravenously infected with different doses (from 1+ù10(7) to 5+ù10(9) bacteria per mouse) of c. ulcerans strains, namely 809 (from human lower resp ...201121742447
concurrent diphtheria and infectious mononucleosis: difficulties for management, investigation and control of diphtheria in developing countries.we report a case of concurrent diphtheria and infectious mononucleosis in a brazilian 11-year-old child. two days after started the specific treatment for diphtheria the case was discharged following clinical recovery. this case highlights the difficulties to diagnose diphtheria clinically in partially immunized individuals and for management and control of diphtheria in developing countries.201121680765
Plasticity of Corynebacterium diphtheriae pathogenicity islands revealed by PCR.Despite the existence of a vaccine against diphtheria, this disease remains endemic and is reemerging in several regions due to many factors, including variations in genes coding for virulence factors. One common feature of virulence factors is their high concentration in pathogenicity islands (PAIs), very unstable regions acquired via horizontal gene transfer, which has lead to the emergence of various bacterial pathogens. The 13 putative PAIs in Corynebacterium diphtheriae NCTC 13129 and the r ...201121732292
Corynebacterium epidermidicanis sp. nov., isolated from a dog's skin.A Gram-stain positive, pleomorphic, oxidase-negative, non-motile isolate from the skin of a dog, designated strain 410T, was subjected to comprehensive taxonomic characterization. Comparison of the 16S rRNA gene sequence showed highest similarities to Corynebacterium diphtheriae, Corynebacterium pseudotuberculosis, and Corynebacterium ulcerans (96.1-96.7%). The quinone system consisted predominantly of MK-8(H2) and MK-9(H2). The polar lipid profile of strain 410T contained the major compounds d ...201122081710
Overexpression and purification of the recombinant diphtheria toxin variant CRM197 in Escherichia coli.The expression of the recombinant diphtheria toxin mutant CRM197 in bacteria other than Corynebacterium diphtheriae has proven to be difficult. Here we propose a new and alternative procedure for the production of full-length CRM197 in Escherichia coli. The present study relates specifically to the expression of an artificial sequence and to a method for the isolation and purification of the corresponding protein. In particular, a synthetic gene coding for CRM197, bearing a short histidine tag a ...201121889551
Synthesis, characterization and antibacterial studies on some mixed ligand thorium complexes with N- and O-donor ligands.Mixed ligand Th(IV) complexes of the type [M(Q)(L)(NO3)2] x 2H2O have been synthesized using 8-hydroxyquinoline (HQ) as a primary ligand and N- and/or O- donor amino acids (HL) such as L-threonine, L-tryptophan and L-isoleucine as secondary ligands. The metal complexes have been characterized on the basis of elemental analysis, electrical conductance, room temperature magnetic susceptibility measurements, spectral and thermal studies. The electrical conductance studies of the complexes in DMF in ...201122125953
[monoclonal antibodies labeled with colloidal gold for immunochromatographic express analysis of diphtheria toxin].one-step rapid immunochromatographic method for detection of diphtheria toxin in different water samples (phosphate buffer, milk, human nasopharyngeal swab) with the conjugate of monoclonal antibodies labeled with colloidal gold was developed. the limit of visible detection of the diphtheria toxin is 10 ng/ml and 15 min time analysis. the use of silver sensitivity enhancement and scanning equipment decreased the detection limit to 1.25 ng/ml.201121899052
[The use of MLVA for Corynebacterium diphtheriae genotyping--preliminary studies].The complete genome sequence of strain NCTC 13129 C. diphtheriae were investigated in order to identify tandem repeats (VNTR). From 75 VNTR loci identified in the genome 14 were selected. Primers were designed and PCR conditions were optimized for amplification of the selected VNTR markers. Preliminary studies of usefulness of selected VNTR markers were conducted using a group of 28 C. diphtheriae strains. From 14 markers 8 were regarded as potentially useful. The diversity of individual markers ...201122184915
Backbone and side chain (1)H, (13)C and (15)N resonance assignments of the catalytic domain of diphtheria toxin.Diphtheria is a serious upper respiratory tract disease caused by the diphtheria toxin (DT) secreted from the bacteria Corynebacterium diphtheriae. Vaccination is the best way to protect against this infectious disease. Diphtheria vaccines are prepared by isolating, purifying and chemically deactivating DT. Although toxoids have been used for decades in immunization, there is still little understanding at the molecular level of the process of toxoid preparation, and how chemical treatment enhanc ...201122205447
pentapeptide commonality between corynebacterium diphtheriae toxin and the homo sapiens proteome.cross-reactivity may affect diagnostic tests and cause harmful autoimmune reactions following immunotherapy. to predict potential cross-reactivity and search for safe immunotherapeutic approaches, we analyzed sequence identity between microbial antigens and the human proteome. using diphtheria toxin (dt) as a model, we examined its patterns of identity with human proteins at the pentapeptide level. dt shares 503 pentapeptides with the human proteome, while only 31 pentapeptides are unique to the ...201121174557
screening for corynebacterium diphtheriae and corynebacterium ulcerans in patients with upper respiratory tract infections 2007-2008: a multicentre european study.diphtheria is now rare in most european countries but, when cases do arise, the case fatality rate is high (5-10%). because few countries continue to routinely screen for the causative organisms of diphtheria, the extent to which they are circulating amongst different european populations is largely unknown. during 2007-2008, ten european countries each screened between 968 and 8551 throat swabs from patients with upper respiratory tract infections. six toxigenic strains of corynebacterium dipht ...201120491827
development of a loop-mediated isothermal amplification assay for the detection of mycobacterium bovis.bovine tuberculosis caused by mycobacterium bovis is an important zoonosis. in this study, a simple, rapid method for detecting this organism was developed based on loop-mediated isothermal amplification of the mpt83 gene. the technique will be of value in the clinical and field-based diagnosis of m. bovis and can differentiate it from other bacteria such as corynebacterium diphtheriae, streptococcus pneumoniae, β-haemolytic streptococci, pseudomonas aeruginosa, yersinia pseudotuberculosis, stap ...201120138787
[etiologic detection and epidemiological analysis of one suspected case of diphtheria in guangdong province].to clarify the diagnosis of one suspected case of diphtheria in guangdong province by epidemiological analysis and etiologic detection.201122321591
a case of diphtheria in sweden, october 2011.in october 2011, a child who had arrived in sweden from somalia presented with atypical tonsillitis, was treated with penicillin and the symptoms resolved. a throat swab was positive for toxigenic corynebacterium diphtheriae. the child's family were then vaccinated with diphtheria, tetanus and pertussis vaccine and screened for c. diphtheriae. no secondary cases were found. a high level of adherence to childhood vaccination programmes is an effective way to protect populations against diphtheria ...201122221495
emergence of coryneforms in osteomyelitis and orthopaedic surgical site infections.coryneform species other than corynebacterium diphtheriae are coming up as important pathogens with the potential to cause serious and life-threatening infections not only in immunocompromised but in immunocompetent individuals as well. the exact infectious potential of these bacteria and their rational antimicrobial treatment is a challenging but essential task.201123393527
draft genome sequence of corynebacterium diphtheriae biovar intermedius nctc 5011.we report an annotated draft genome of the human pathogen corynebacterium diphtheriae bv. intermedius nctc 5011. this strain is the first c. diphtheriae bv. intermedius strain to be sequenced, and our results provide a useful comparison to the other primary disease-causing biovars, c. diphtheriae bv. gravis and c. diphtheriae bv. mitis. the sequence has been deposited at ddbj/embl/genbank with the accession number ajvh01000000.201222887653
[occurence of pili genes in corynebacterium diphtheriae strains].adhesion of pathogenic bacteria to host cells is a crucial step during infection. the presence of specific adhesion factors on the bacterial cell surface determines the tropism of the pathogen to the tissues expressing certain surface receptors. the adhesion is mediated primarily by filamentous structures called pili. three distinct pilus structures can be produced by corynebacterium diphtheriae: spaa-, spad- and spah-type pili. pilus genes encode a total of nine pilus proteins, named spaa throu ...201222808726
the draft genome sequence of corynebacterium diphtheriae bv. mitis nctc 3529 reveals significant diversity between the primary disease-causing biovars.we report the draft genome of the human pathogen corynebacterium diphtheriae bv. mitis nctc 3529. this is the first c. diphtheriae bv. mitis strain to be sequenced and reveals significant differences from the other primary biovar, c. diphtheriae bv. gravis.201222628502
contour and persistence length of corynebacterium diphtheriae pili by atomic force microscopy.many bacteria are characterized by nanoscale ultrastructures, for example s-layers, flagella, fimbriae, or pili. the last two are especially important for attachment to different abiotic and biotic surfaces and for host-pathogen interactions. in this study, we investigated the geometric and elastic properties of pili of different corynebacterium diphtheriae strains by atomic force microscopy (afm). we performed quantitative contour-length analysis of bacterial pili and found that the visible con ...201222588485
diphtheria in europe: current problems and new challenges.diphtheria, caused by toxigenic strains of corynebacterium diphtheriae, is an ancient disease with high incidence and mortality that has always been characterized by epidemic waves of occurrence. whilst towards the beginning of the 1980s, many european countries were progressing towards the elimination of diphtheria, an epidemic re-emergence of diphtheria in the russian federation and the newly independent states of the former soviet union demonstrated a continuous threat of the disease into the ...201222568715
usefulness of 16s rdna sequencing for the diagnosis of infective endocarditis caused by corynebacterium diphtheriae.we report a rare case of infective endocarditis caused by corynebacterium diphtheriae in an 8-year-old boy, 2 years after a right ventricular outflow tract reconstruction with a bovine contegra valved conduit. the patient recovered well after an rv-pa conduit enblock explantation and replacement with an aortic homograft with antibiotic treatment. all bacteriological cultures of excised tissue and blood were negative. the aetiological agent was identified as c. diphtheriae subsp. gravis by 16s rd ...201222538997
fatal laryngeal diphtheria in a uk child.over the last century, the infectious causes of acute upper airway obstruction have changed dramatically. toxigenic corynebacterium diphtheriae has become rare in the uk due to national immunisation programmes. since 1986, eight sporadic cases of c diphtheriae were reported, all of whom had recently returned from endemic areas. we describe a case of fatal laryngeal diphtheria in an unimmunised child. although appropriate antimicrobial cover was provided, antitoxin was not administered due to a l ...201222535233
purification and structural characterization of siderophore (corynebactin) from corynebacterium diphtheriae.during infection, corynebacterium diphtheriae must compete with host iron-sequestering mechanisms for iron. c. diphtheriae can acquire iron by a siderophore-dependent iron-uptake pathway, by uptake and degradation of heme, or both. previous studies showed that production of siderophore (corynebactin) by c. diphtheriae is repressed under high-iron growth conditions by the iron-activated diphtheria toxin repressor (dtxr) and that partially purified corynebactin fails to react in chemical assays fo ...201222514641
identification and molecular discrimination of toxigenic and nontoxigenic diphtheria corynebacterium strains by combined real-time polymerase chain reaction assays.with the recognition of several diphtheria outbreaks and the emergence of nontoxigenic corynebacteria strains, there has been renewed interest in the development of laboratory diagnostic methods. previously reported polymerase chain reaction (pcr) assays can have low diagnostic sensitivity or give species misidentifications among clinical isolates. the aim of the present study was the development of combined real-time pcr assays, based on the tox and rpob genes, for the detection and differentia ...201222494559
bloodstream infection caused by nontoxigenic corynebacterium diphtheriae in an immunocompromised host in the united states.corynebacterium species are well-known causes of catheter-related bloodstream infections. toxigenic strains of corynebacterium diphtheriae cause respiratory diphtheria. we report a bloodstream infection caused by a nontoxigenic strain of c. diphtheriae and discuss the epidemiology, possible sources of the infection, and the implications of rapid species identification of corynebacteria.201222493337
pyopericardium followed by constrictive pericarditis due to corynebacterium diphtheriae.pyopericardium is a rare entity associated with a high mortality. we report a case of a 44-year old man presenting with simultaneous constrictive pericarditis and pyopericardium due to corynebacterium diphtheriae. pericardiectomy and epicardiectomy were performed without cardiopulmonary bypass, with an excellent result.201222402499
cases of cutaneous diphtheria in new zealand: implications for surveillance and management.diphtheria is an acute bacterial illness caused by toxigenic strains of corynebacterium diphtheriae (c. diphtheriae). we describe two epidemiologically-linked cases of skin infections from which toxigenic c. diphtheriae was isolated, and discuss implications for diphtheria surveillance and management in new zealand.201222382258
[macrophage apoptosis as a mechanism of pathogenic effect of diphtheria infectious agent].study of the apoptogenic effect of corynebacterium diphtheriae toxigenic strains on mice peritoneal macrophages in vitro.201223163039
Characterization and Comparison of Invasive Corynebacterium diphtheriae Isolates from France and Poland.Corynebacterium diphtheriae, the agent of diphtheria, is rarely responsible for bacteremia. However, high numbers of bacteremia have been reported in countries with extensive immunization coverage. Here, we used molecular and phenotypic tools to characterize and compare 42 invasive isolates collected in France (including New Caledonia) and Poland over a 23-year period.201222090411
corynebacterium diphtheriae 67-72p hemagglutinin, characterized as the protein dip0733, contributes to invasion and induction of apoptosis in hep-2 cells.although corynebacterium diphtheriae has been classically described as an exclusively extracellular pathogen, there is growing evidence that it may be internalized by epithelial cells. the aim of the present report was to investigate the nature and involvement of the surface-exposed non-fimbrial 67-72 kda proteins (67-72p), previously characterized as adhesin/hemagglutinin, in c. diphtheriae internalization by hep-2 cells. transmission electron microscopy and bacterial internalization inhibition ...201222239957
microbiologic profile of endodontic infections from hiv- and hiv+ patients using multiple-displacement amplification and checkerboard dna-dna hybridization.to compare the microbiota of endodontic infections in necrotic pulp from hiv-negative and hiv-positive subjects.201222335194
the chra response regulator in corynebacterium diphtheriae controls hemin-regulated gene expression through binding to the hmuo and hrtab promoter regions.corynebacterium diphtheriae, the etiologic agent of diphtheria, utilizes heme and hemoglobin (hb) as iron sources for growth. heme-iron utilization involves hmuo, a heme oxygenase that degrades cytosolic heme, resulting in the release of heme-associated iron. expression of the hmuo promoter is under dual regulation, in which transcription is repressed by dtxr and iron and activated by a heme source, such as hemin or hb. hemin-dependent activation is mediated primarily by the chras two-component ...201222287525
evaluation of invertebrate infection models for pathogenic corynebacteria.for several pathogenic bacteria, model systems for host-pathogen interactions were developed, which provide the possibility of quick and cost-effective high throughput screening of mutant bacteria for genes involved in pathogenesis. a number of different model systems, including amoeba, nematodes, insects, and fish, have been introduced, and it was observed that different bacteria respond in different ways to putative surrogate hosts, and distinct model systems might be more or less suitable for ...201222443092
characterization of oxyr as a negative transcriptional regulator that represses catalase production in corynebacterium diphtheriae.corynebacterium diphtheriae and corynebacterium glutamicum each have one gene (cat) encoding catalase. in-frame δcat mutants of c. diphtheriae and c. glutamicum were hyper-sensitive to growth inhibition and killing by h(2)o(2). in c. diphtheriae c7(β), both catalase activity and cat transcription decreased ~2-fold during transition from exponential growth to early stationary phase. prototypic oxyr in escherichia coli senses oxidative stress and it activates katg transcription and catalase produc ...201222438866
pangenomic study of corynebacterium diphtheriae that provides insights into the genomic diversity of pathogenic isolates from cases of classical diphtheria, endocarditis, and pneumonia.corynebacterium diphtheriae is one of the most prominent human pathogens and the causative agent of the communicable disease diphtheria. the genomes of 12 strains isolated from patients with classical diphtheria, endocarditis, and pneumonia were completely sequenced and annotated. including the genome of c. diphtheriae nctc 13129, we herewith present a comprehensive comparative analysis of 13 strains and the first characterization of the pangenome of the species c. diphtheriae. comparative genom ...201222505676
bacteria and their toxins tamed for immunotherapy.bacterial toxins share the ability to enter host cells to target various intracellular proteins and to modulate host immune responses. over the last 20 years, toxins and their mutated variants, as well as live attenuated bacteria, have been exploited for vaccination and immunotherapy of various infectious, malignant and autoimmune diseases. the ability of bordetella pertussis adenylate cyclase toxin to translocate its adenylate cyclase domain across the host cell membrane, as well as the pathway ...201222339216
efficient preparation and metal specificity of the regulatory protein tror from the human pathogen treponema pallidum.tror is a putative metal-dependent regulatory protein that has been linked to the virulence of the human pathogen treponema pallidum. it shares high homology with the well-known iron-dependent regulatory protein dtxr from corynebacterium diphtheriae, as well as the manganese-dependent mntr from bacillus subtilis. however, it has been uncertain whether manganese or zinc is the natural cofactor of tror to date. herein, we established an efficient method named "double-fusion tagging" to obtain solu ...201323945957
characterization of c-s lyase from c. diphtheriae: a possible target for new antimicrobial drugs.the emergence of antibiotic resistance in microbial pathogens requires the identification of new antibacterial drugs. the biosynthesis of methionine is an attractive target because of its central importance in cellular metabolism. moreover, most of the steps in methionine biosynthesis pathway are absent in mammals, lowering the probability of unwanted side effects. herein, detailed biochemical characterization of one enzyme required for methionine biosynthesis, a pyridoxal-5'-phosphate (plp-) de ...201324106714
induction of the nfκ-b signal transduction pathway in response to corynebacterium diphtheriae infection.corynebacterium diphtheriae, the causative agent of diphtheria, has been thoroughly studied with respect to toxin production and pili formation, while knowledge on host responses to c. diphtheriae infection is limited. in this study, we studied adhesion to and invasion of epithelial cells by different c. diphtheriae isolates. when nfκ-b reporter cell lines were used to monitor the effect of c. diphtheriae infection on human cells, strain-specific differences were observed. while adhesion to host ...201323125120
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