Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| potential pathogenic role of aggregative-adhering corynebacterium diphtheriae of different clonal groups in endocarditis. | invasive diseases caused by corynebacterium diphtheriae have been described increasingly. several reports indicate the destructive feature of endocarditis attributable to nontoxigenic strains. however, few reports have dealt with the pathogenicity of invasive strains. the present investigation demonstrates a phenotypic trait that may be used to identify potentially invasive strains. the study also draws attention to clinical and microbiological aspects observed in 5 cases of endocarditis due to ... | 2008 | 19099151 |
| [types of corynebacterium diphtheriae strains isolated in poland in 2004-2008]. | biotyping and genotyping were performed for corynebacterium diphtheriae strains isolated from humans in poland during last several years. all the strains belonged to the same biotype and genetic clone. similar situation has not yet been described in international literature, although nontoxigenic c. diphtheriae strains have been isolated more frequently in developed countries. however, strains isolated and investigated in other countries revealed heterogeneity of biotypes and genotypes. | 2008 | 19143171 |
| [immunization of adult population of russia against diphtheria in 2006-2007]. | the vaccination coverage against diphtheria in the adult population of russia in 2006-2007 was analyzed in different age, professional and social groups and reasons of absent immunization. vaccination coverage in adults was 95.3%, of them 92.5% were boosted (i.e. completely immunized) and only 7.5% were in process of vaccination. vaccination coverage was high in the majority of regions. mean vaccination coverage in adults aged 25-49 ages was 96.2-96.5% whereas in adults > or =50 years it was low ... | 2008 | 19186541 |
| skin microbiota: a source of disease or defence? | microbes found on the skin are usually regarded as pathogens, potential pathogens or innocuous symbiotic organisms. advances in microbiology and immunology are revising our understanding of the molecular mechanisms of microbial virulence and the specific events involved in the host-microbe interaction. current data contradict some historical classifications of cutaneous microbiota and suggest that these organisms may protect the host, defining them not as simple symbiotic microbes but rather as ... | 2008 | 18275522 |
| housekeeping sortase facilitates the cell wall anchoring of pilus polymers in corynebacterium diphtheriae. | many surface proteins in gram-positive bacteria are covalently linked to the cell wall through a transpeptidation reaction catalysed by the enzyme sortase. corynebacterium diphtheriae encodes six sortases, five of which are devoted to the assembly of three distinct types of pilus fibres--srta for the spaa-type pilus, srtb/srtc for the spad-type pilus, and srtd/srte for the spah-type pilus. we demonstrate here the function of srtf, the so-called housekeeping sortase, in the cell wall anchoring of ... | 2007 | 17919283 |
| quantification of diphtheria toxin mediated adp-ribosylation in a solid-phase assay. | because of reduced vaccination programs, the number of diphtheria infections has increased in the last decade. diphtheria toxin (dt) is expressed by corynebacterium diphtheriae and is responsible for the lethality of diphtheria. dt inhibits cellular protein synthesis by adp-ribosylation of the eukaryotic elongation factor 2 (eef2). no in vitro system for the quantification of dt enzymatic activity exists. we developed a solid-phase assay for the specific detection of adp-ribosylation by dt. | 2007 | 17712004 |
| bacteriological & epidemiological characteristics of diphtheria cases in & around delhi -a retrospective study. | diphtheria infections caused by the different toxigenic biotypes of corynebacterium diphtheriae are endemic in delhi. information on biochemical identification, toxigenicity and antimicrobial susceptibility to this bacterium is scanty. this retrospective study was carried out to identify isolated corynebacteria biochemically, determine their toxigenicity, drug sensitivity and some epidemiological characteristics of diphtheria cases from delhi and adjoining states for the period 1998-2004. | 2007 | 18219082 |
| qualitative and quantitative analysis of microbial aerosols in selected areas within the college of dentistry, king saud university. | to investigate qualitatively and quantitatively the bacterial aerosols before, during, and after clinical work sessions in different areas within a multichair dental clinic, an isolation clinic, the sterilization center, and the prosthetic laboratory in the college of dentistry, king saud university. in addition, the contributions of aerosols generated by different types of dental procedures were investigated. | 2007 | 17568825 |
| backbone dynamics in an intramolecular prolylpeptide-sh3 complex from the diphtheria toxin repressor, dtxr. | the diphtheria toxin repressor contains an sh3-like domain that forms an intramolecular complex with a proline-rich (pr) peptide segment and stabilizes the inactive state of the repressor. upon activation of diphtheria toxin repressor (dtxr) by transition metals, this intramolecular complex must dissociate as the sh3 domain and pr segment form different interactions in the active repressor. here we investigate the dynamics of this intramolecular complex using backbone amide nuclear spin relaxati ... | 2007 | 17976643 |
| interplay between dtxr and nitric oxide reductase activities: a functional genomics approach indicating involvement of homologous protein domains in bacterial pathogenesis. | corynebacterium diphtheriae pathogenesis depends on the production of toxin (dtx), which in turn depends on a micromolar concentration of nitric oxide (no)-mediated deactivation of dtxr (an iron-dependent regulator). inside a host, the pathogen often encounters excess of no that acts as an oxidative toxicant. therefore a critical level of no needs to be maintained by the pathogen. this necessitates reduction of excess no by the presence of a reductase, namely nitric oxide reductase (nor). simila ... | 2007 | 17877539 |
| corynebacterium diphtheriae: identification and characterization of a channel-forming protein in the cell wall. | the cell wall fraction of the gram-positive, nontoxic corynebacterium diphtheriae strain c8r(-) tox- (=atcc 11913) contained a channel-forming protein, as judged from reconstitution experiments with artificial lipid bilayer experiments. the channel-forming protein was present in detergent-treated cell walls and in extracts of whole cells obtained using organic solvents. the protein had an apparent molecular mass of about 66 kda as determined on tricine-containing sodium dodecyl sulfate-polyacryl ... | 2007 | 17720794 |
| nmr assignments of cd-ho, a 24 kda heme oxygenase from corynebacterium diphtheria. | we are employing a number of selective in vitro and in vivo methods including nmr to screen compounds that bind to heme oxygenases from pathogenic bacteria. we report the nearly complete hn, n, co, calpha and cbeta chemical shift assignments of a 215-amino acid ho from corynebacterium diphtheria in three forms, apo cd-ho-g135a, apo cd-ho and co-bound ferrous holo cd-ho; these assignments will enable us to identify residues on cd-ho that are perturbed upon binding to selected compounds, and to he ... | 2007 | 19636825 |
| role of the n-terminal helix in the metal ion-induced activation of the diphtheria toxin repressor dtxr. | the metal ion-regulated transcriptional repressor dtxr has been shown to repress the transcription of the diphtheria toxin and other genes associated with ferrous ion homeostasis in corynebacterium diphtheriae. in vivo studies of single-alanine mutations located in the n-terminal helix of dtxr show that the activity of the mutants is reduced compared to that of the wild type. the three-dimensional structures of the apo and activated forms of dtxr show conformational changes in the n-terminal hel ... | 2007 | 17902703 |
| determinants of protection against diphtheria in adult hemodialysis patients. | diphtheria is of great epidemiological concern. although mainly observed during childhood, unvaccinated adults and relatively immunocompromised patients are at increased risk for acquiring diphtheria. we aimed to determine the rates and certain determinants of protection against diphtheria in adult hemodialysis (hd) patients. protection rates of 322 hd patients were compared with 65 diabetes mellitus type 2 (dm) patients and 65 healthy controls. a questionnaire was held in regard to smoking habi ... | 2007 | 17994451 |
| prevalence of diphtheria and tetanus antibodies and circulation of corynebacterium diphtheriae in são paulo, brazil. | the introduction of routine vaccination against tetanus and diphtheria in brazil has decreased the incidence and changed the epidemiology of both diseases. we then investigated the prevalence of corynebacterium diphtheriae carrier status and diphtheria and tetanus immunity in são paulo, brazil. from november 2001 to march 2003, 374 individuals were tested for the presence of c. diphtheriae in the naso-oropharynx and of serum diphtheria and tetanus antibodies. participants were all healthy indivi ... | 2007 | 17906776 |
| [development studies of lyophilized standard diphtheria-tetanus-pertussis vaccines]. | in this study, diphtheria, tetanus and pertussis vaccine components were prepared as the formulations of diphtheria-tetanus-pertussis (dtp), diphtheria-tetanus (dt) for children, diphtheria-tetanus (td) for adults, and tetanus toxoid (tt), respectively. alhydrogel-adsorbed vaccines prepared to contain the stabilizing substances were lyophilized and the immunogenicity tests were carried out both in vivo and in vitro. the potencies of the tetanus component of the vaccines were obtained by the leth ... | 2007 | 17682702 |
| analysis of secreted protein profile and enzymatic activities from corynebacterium diphtheriae and bordetella pertussis on production batch media using peptide quenched fluorescent substrates. | proteases were identified and characterized from the culture supernatant of the c. diphtheriae and b. pertussis bacteria. the proteases were secreted in the media and detected at the end of the exponential growth phase. activity was detected in some fluorescent substrates, based on selected protein sequences such as insuline beta-chain, bradykinin, and synaptobrevin. the proteases were purified by means of gel filtration chromatography. sodium dodecyl sulfate-polyacrylamide gel electrophoresis ( ... | 2007 | 17849290 |
| [the humoral immunity against diphtheria]. | results of the conducted study showed that naturally acquired antibacterial and postvaccinal antitoxic antibodies against diphtheria were found in human blood sera. challenge of adt-m toxoid to adults resulted in production of antitoxic as well as antibacterial antibodies in high concentrations. in response to challenge of adt-m toxoid simultaneously with bacterial vaccine against diphtheria codivac both antibacterial and antitoxic antibodies were synthesized in blood on optimal physiologic leve ... | 2007 | 17882831 |
| [study of diphtheria anatoxins in immunochemical and tissue culture assays]. | equine diphtheria antitoxins from different manufacturers were studied. their immunochemical interaction with diphtheria toxin, toxoid, and antigens of corynebacterium diphtheriae in elisa and immunoblotting assays as well as biological activity in cho cell assay were compared. the discovered differences between antitoxin samples with stated equal activity in iu/ml point to heterogeneity of antigen composition in preparations used for immunization. mentioned methods allow to standardize antitoxi ... | 2007 | 17882833 |
| diatomic ligand discrimination by the heme oxygenases from neisseria meningitidis and pseudomonas aeruginosa. | heme oxygenases have an increased binding affinity for o2 relative to co. such discrimination is critical to the function of ho enzymes because one of the main products of heme catabolism is co. kinetic studies of mammalian and bacterial ho proteins reveal a significant decrease in the dissociation rate of o2 relative to other heme proteins such as myoglobin. here we report the kinetic rate constants for the binding of o2 and co by the heme oxygenases from neisseria meningitidis (nmho) and pseud ... | 2007 | 17095508 |
| nitrogen metabolism and nitrogen control in corynebacteria: variations of a common theme. | the published genome sequences of corynebacterium diphtheriae, corynebacterium efficiens, corynebacterium glutamicum and corynebacterium jeikeium were screened for genes encoding central components of nitrogen source uptake, nitrogen assimilation and nitrogen control systems. interestingly, the soil-living species c. efficiens and c. glutamicum exhibit a broader spectrum of genes for nitrogen transport and metabolism than the pathogenic species c. diphtheriae and c. jeikeium. the latter are char ... | 2007 | 17183220 |
| bacteriophage-based vectors for site-specific insertion of dna in the chromosome of corynebacteria. | in corynebacterium diphtheriae, diphtheria toxin is encoded by the tox gene of some temperate corynephages such as beta. beta-like corynephages are capable of inserting into the c. diphtheriae chromosome at two specific sites, attb1 and attb2. transcription of the phage-encoded tox gene, and many chromosomally encoded genes, is regulated by the dtxr protein in response to fe(2+) levels. characterizing dtxr-dependent gene regulation is pivotal in understanding diphtheria pathogenesis and mechanis ... | 2007 | 17275217 |
| complete genome sequence of the erythromycin-producing bacterium saccharopolyspora erythraea nrrl23338. | saccharopolyspora erythraea is used for the industrial-scale production of the antibiotic erythromycin a, derivatives of which play a vital role in medicine. the sequenced chromosome of this soil bacterium comprises 8,212,805 base pairs, predicted to encode 7,264 genes. it is circular, like those of the pathogenic actinomycetes mycobacterium tuberculosis and corynebacterium diphtheriae, but unlike the linear chromosomes of the model actinomycete streptomyces coelicolor a3(2) and the closely rela ... | 2007 | 17369815 |
| corynebacterium diphtheriae employs specific minor pilins to target human pharyngeal epithelial cells. | adherence to host tissues mediated by pili is pivotal in the establishment of infection by many bacterial pathogens. corynebacterium diphtheriae assembles on its surface three distinct pilus structures. the function and the mechanism of how various pili mediate adherence, however, have remained poorly understood. here we show that the spaa-type pilus is sufficient for the specific adherence of corynebacteria to human pharyngeal epithelial cells. the deletion of the spaa gene, which encodes the m ... | 2007 | 17376076 |
| the seroprevalence of diphtheria among adults in izmir-turkey. | a serological survey to determine the immunity to diphtheria in the adult population in izmir-turkey was conducted according to the recommendations of the world health organization. a total of 339 blood samples were collected from subjects aged between 20 and 81, and diphtheria antitoxin levels were measured by the enzyme linked immunosorbent assay method. titers below 0.1 iu/ml were considered to show insufficient immunity. of the studied population, 56.3% had showed insufficient immunity again ... | 2007 | 17395342 |
| corynebacterium diphtheriae spoligotyping based on combined use of two crispr loci. | a large diphtheria epidemic in the 1990s in russia and neighboring countries underlined the importance of permanent surveillance of the circulating and emerging clones of corynebacterium diphtheriae, and hence there is a need for highly discriminatory, simple and portable typing methods. in the complete genome sequence of c. diphtheriae strain nctc13129, we previously identified in silico two clustered, regularly interspaced short palindromic repeat (crispr) loci, and developed a macroarray-base ... | 2007 | 17431853 |
| the chra-chrs and hrra-hrrs signal transduction systems are required for activation of the hmuo promoter and repression of the hema promoter in corynebacterium diphtheriae. | transcription of the corynebacterium diphtheriae hmuo gene, which encodes a heme oxygenase involved in heme iron utilization, is activated in a heme- or hemoglobin-dependent manner in part by the two-component system chra-chrs. mutation of either the chra or the chrs gene resulted in a marked reduction of hemoglobin-dependent activation at the hmuo promoter in c. diphtheriae; however, it was observed that significant levels of hemoglobin-dependent expression were maintained in the mutants, sugge ... | 2007 | 17353293 |
| [point mutations in tox promoter/operator and diphtheria toxin repressor (dtxr) gene associated with the level of toxin production by corynebacterium diphtheriae strains isolated in belarus]. | dna fragments 129 bp in length containing promoter region of the tox gene from 81 toxigenic strains corynebacterium diphtheriae were analyzed using the sscp (single strand conformational polymorphism). we found that only two strains had mutations; the strains also had highest levels of toxin production (over 5120 vero cd50/ml). other strains were characterized either as high-level toxin-producing (640-5120 vero cd50/ml, 41 strains) or low-level toxin-producing (40-320 vero cd50/ml, 38 strains). ... | 2007 | 17354605 |
| cutaneous diphtheroid infection and review of other cutaneous gram-positive bacillus infections. | cutaneous diphtheria is a rare infection in the united states. this article presents a case of genital ulcerations, which were likely secondary to cutaneous coryneform bacterial infection, and reviews the literature concerning the diagnosis and management of this entity. in addition, we briefly review other gram-positive bacillus bacterial infections of the skin. | 2007 | 17569399 |
| a six-month audit of the isolation of fusobacterium necrophorum from patients with sore throat in a district general hospital. | fusobacterium necrophorum is an obligate anaerobe believed to be a member of the normal flora of the human oropharangeal and urogenital tract. it has been associated with deep-seated infections and was first described in 1936 by lemierre, a french microbiologist. there is now strong evidence to suggest that it is also a cause of recurrent sore throat and persistent sore throat syndrome (psts) without leading to full systemic infection. it is considered to be the second most common cause of sore ... | 2007 | 17633139 |
| pili mediate specific adhesion of streptococcus pyogenes to human tonsil and skin. | very little is known about the biological functions of pili that have recently been found to be expressed by important gram-positive pathogens such as corynebacterium diphtheriae, streptococcus agalacticae, s. pneumoniae and s. pyogenes. using various ex vivo tissue and cellular models, here we show that pili mediate adhesion of serotype m1 s. pyogenes strain sf370 to both human tonsil epithelium and primary human keratinocytes, which represent the two main sites of infection by this human-speci ... | 2007 | 17359232 |
| the iclr-type transcriptional repressor ltbr regulates the expression of leucine and tryptophan biosynthesis genes in the amino acid producer corynebacterium glutamicum. | the transcriptional regulator cg1486 of corynebacterium glutamicum atcc 13032 is a member of the iclr protein family and belongs to the conserved set of regulatory proteins in corynebacteria. a defined deletion in the cg1486 gene, now designated ltbr (leucine and tryptophan biosynthesis regulator), led to the mutant strain c. glutamicum ib1486. according to whole-genome expression analysis by dna microarray hybridizations, transcription of the leub and leucd genes encoding enzymes of the leucine ... | 2007 | 17259312 |
| comparative analysis of hmuo function and expression in corynebacterium species. | we have constructed defined deletions in the hmuo gene from corynebacterium diphtheriae and corynebacterium ulcerans and show that the c. ulcerans hmuo mutation results in a significant reduction in hemoglobin-iron utilization, whereas in c. diphtheriae strains, deletion of hmuo caused no or only partial reduction in the utilization of heme as an iron source. we also show that expression from the c. ulcerans hmuo promoter exhibits minimal regulation by iron and heme whereas transcription from th ... | 2007 | 17322319 |
| transcription of the contiguous sigb, dtxr, and gale genes in corynebacterium diphtheriae: evidence for multiple transcripts and regulation by environmental factors. | the iron-dependent transcriptional regulator dtxr from corynebacterium diphtheriae is the prototype for a family of metal-dependent regulators found in diverse bacterial species. the structure of dtxr and its action as a repressor have been extensively characterized, but little is known about expression of dtxr. in the current study, we investigated transcription of dtxr as well as the sigb and gale genes located immediately upstream and downstream from dtxr, respectively. we identified two prom ... | 2006 | 16585757 |
| assembly of distinct pilus structures on the surface of corynebacterium diphtheriae. | different surface organelles contribute to specific interactions of a pathogen with host tissues or infectious partners. multiple pilus gene clusters potentially encoding different surface structures have been identified in several gram-positive bacterial genomes sequenced to date, including actinomycetales, clostridia, corynebacteria, and streptococci. corynebacterium diphtheriae has been shown to assemble a pilus structure, with sortase srta essential for the assembly of a major subunit spaa a ... | 2006 | 16452436 |
| the life and death of translation elongation factor 2. | eef2 (eukaryotic elongation factor 2) occupies an essential role in protein synthesis where it catalyses the translocation of the two trnas and the mrna after peptidyl transfer on the 80 s ribosome. recent crystal structures of eef2 and the cryo-electron microscopy reconstruction of its 80 s complex now provide a substantial structural framework for dissecting the functional properties of this factor. the factor can be modified by either phosphorylation or adp-ribosylation, which results in cess ... | 2006 | 16246167 |
| the dtxr regulon of corynebacterium glutamicum. | previous studies with corynebacterium diphtheriae and mycobacterium species revealed that the transcriptional regulator dtxr and its ortholog ider play a central role in the control of iron metabolism. in the present work, we used genome-based approaches to determine the dtxr regulon of corynebacterium glutamicum, a nonpathogenic relative of c. diphtheriae. first, global gene expression of a dtxr deletion mutant was compared with that of the wild type using dna microarrays. second, we used a com ... | 2006 | 16585752 |
| [immunoloical aspects of the antropogenic response to the antigens of symbiotic non-toxigenic diphtherial corynebacteria]. | corynebacteria, being ancient symbionts of open cavities of human body, carry unique, balanced immunogenic stimuli, formed in the process of evolution, thus maintaining non-specific resistance at a certain level. they favor formation of human microcenotic communities as a normal biological and physiological phenomenon. codivak, a preparation of natural antigens of a symbiotic strain of non-toxigenic diphtherial corynebacteria, is able to correct not only disturbances of oropharyngeal immunity, b ... | 2006 | 16496952 |
| human alpha-defensins neutralize toxins of the mono-adp-ribosyltransferase family. | various bacterial pathogens secrete toxins, which are not only responsible for fatal pathogenesis of disease, but also facilitate evasion of host defences. one of the best-known bacterial toxin groups is the mono-adp-ribosyltransferase family. in the present study, we demonstrate that human neutrophil alpha-defensins are potent inhibitors of the bacterial enzymes, particularly against dt (diphtheria toxin) and eta (pseudomonas exotoxin a). hnp1 (human neutrophil protein 1) inhibited dt- or eta-m ... | 2006 | 16817779 |
| emergence of an invasive clone of nontoxigenic corynebacterium diphtheriae in the urban poor population of vancouver, canada. | invasive disease due to corynebacterium diphtheriae is rare in north america. here we describe the emergence of a predominant clone of a nontoxigenic strain of c. diphtheriae in the impoverished population of vancouver's downtown core. this clone has caused significant morbidity and contributed to at least two deaths. over a 5-year period, seven cases of bacteremia due to c. diphtheriae were detected in patients admitted to vancouver hospitals. injection drug use, diabetes mellitus, skin coloniz ... | 2006 | 16672385 |
| cluster of invasive infections, including endocarditis, caused by nontoxigenic corynebacterium diphtheriae. | 2006 | 17100042 | |
| translation elongation factor 2 anticodon mimicry domain mutants affect fidelity and diphtheria toxin resistance. | eukaryotic elongation factor 2 (eef2) mediates translocation in protein synthesis. the molecular mimicry model proposes that the tip of domain iv mimics the anticodon loop of trna. his-699 in this region is post-translationally modified to diphthamide, the target for corynebacterium diphtheriae and pseudomonas aeruginosa toxins. adp-ribosylation by these toxins inhibits eef2 function causing cell death. mutagenesis of the tip of domain iv was used to assess both functions. a h694a mutant strain ... | 2006 | 16950777 |
| type iii pilus of corynebacteria: pilus length is determined by the level of its major pilin subunit. | multiple pilus gene clusters have been identified in several gram-positive bacterial genomes sequenced to date, including the actinomycetales, clostridia, streptococci, and corynebacteria. the genome of corynebacterium diphtheriae contains three pilus gene clusters, two of which have been previously characterized. here, we report the characterization of the third pilus encoded by the spahig cluster. by using electron microscopy and biochemical analysis, we demonstrate that spah forms the pilus s ... | 2006 | 16923899 |
| molecular epidemiology of c. diphtheriae strains during different phases of the diphtheria epidemic in belarus. | the reemergence of epidemic diphtheria in belarus in 1990s has provided us with important information on the biology of the disease and the diversity of the causative agent corynebacterium diphtheriae. molecular investigations were conducted with the aim to analyze the genetic variability of c diphtheriae during the post-epidemic period. | 2006 | 16911772 |
| some unusual manifestations of proteolysis. | in the article the results of the long-term researches revealing the essence of the following three phenomena are generalized. 1. participation of active oxygen species (especially, superoxide radical) in activation of zymogens--plasminogen, trypsinogen, chymotrypsinogen, pepsinogen and in realization of the catalytic (proteolytic) function of a number of proteinases. the essence of the hypothesis of oxygen-dependent reactions of proteolysis is stated. as shown by the example of mouse brain homo ... | 2006 | 17543196 |
| [pathogenicity of corynebacterium diphtheriae circulating in rostov-on-don city and rostov region during interepidemic period]. | main pathogenic characteristics (toxin production, tox-gene detection, adhesiveness) of 59 strains of c. diphtheriae circulating in rostov-on-don city and rostov region in 2004-2005 were studied. study of toxigenicity of 15 tox+ c.di phtheriae strains showed full coincidence of elek immunoprecipitation test and polymerase chain reaction (pcr). presence of part of a-fragment of tox-gene was detected in 5 (11.4%) of 44 c. diphtheriae strains that were negative in elek test. hemagglutinating activi ... | 2006 | 17163130 |
| [pseudomembranous diphtheria caused by corynebacterium ulcerans]. | introduction: pseudomembranous angina are classically caused by corynebacterium diphtheriae. more rarely, it caused by corynebacterium ulcerans, sometimes carrying the diphteric exotoxine. exegeris: we report a new autochton case of pseudomembranous pharyngitis caused by c. ulcerans, carrying the diphteric exotoxine, transmitted by a dog, complicated of velopharyngitis and hypopharyngée paralysis, then of diphtheric polyneuritis. conclusion: although exceptional, diphteria must always be evoked ... | 2006 | 16426709 |
| variable expression of immunoreactive surface proteins of propionibacterium acnes. | despite accumulating data implicating propionibacterium acnes in a variety of diseases, its precise role in infection remains to be determined. p. acnes antigen-specific cd4(+) t cells are present in early inflamed acne lesions and may be involved in the inflammatory response; however, little is known about the specific antigens involved. in this study, b cell and t cell antigens from p. acnes expression libraries were cloned and evaluated and the four predominant proteins identified were invest ... | 2006 | 17159220 |
| design of metal cofactors activated by a protein-protein electron transfer system. | protein-to-protein electron transfer (et) is a critical process in biological chemistry for which fundamental understanding is expected to provide a wealth of applications in biotechnology. investigations of protein-protein et systems in reductive activation of artificial cofactors introduced into proteins remains particularly challenging because of the complexity of interactions between the cofactor and the system contributing to et. in this work, we construct an artificial protein-protein et s ... | 2006 | 16769893 |
| a comparative study on the effect of plant extracts with the antibiotics on organisms of hospital origin. | thirty five plants belonging to twenty families were studied for their antimicrobial activity. among the plants tested, 43 % showed antimicrobial activity. fifteen plants belonging to 10 families exhibited activity against gram positive bacteria and gram negative bacteria. four plants namely azadirachta indica, garadenia jasminoides, magnifera indica, and wrightia tinctora showed an appreciable activity against the gram positive bacteria and seven plants against gram negative organisms. leaf ext ... | 2006 | 22557227 |
| stealth and mimicry by deadly bacterial toxins. | diphtheria toxin and exotoxin a are well-characterized members of the adp-ribosyltransferase toxin family that function as virulence factors in the pathogenic bacteria corynebacterium diphtheriae and pseudomonas aeruginosa. recent high-resolution structural data of the michaelis (enzyme-substrate) complex of the p. aeruginosa toxin with an nad(+) analog and eukaryotic elongation factor 2 (eef2) have provided insights into the mechanism of inactivation of protein synthesis caused by these protein ... | 2006 | 16406634 |
| the dtxr protein acting as dual transcriptional regulator directs a global regulatory network involved in iron metabolism of corynebacterium glutamicum. | the knowledge about complete bacterial genome sequences opens the way to reconstruct the qualitative topology and global connectivity of transcriptional regulatory networks. since iron is essential for a variety of cellular processes but also poses problems in biological systems due to its high toxicity, bacteria have evolved complex transcriptional regulatory networks to achieve an effective iron homeostasis. here, we apply a combination of transcriptomics, bioinformatics, in vitro assays, and ... | 2006 | 16469103 |
| corynebacterial protein kinase g controls 2-oxoglutarate dehydrogenase activity via the phosphorylation status of the odhi protein. | a novel regulatory mechanism for control of the ubiquitous 2-oxoglutarate dehydrogenase complex (odh), a key enzyme of the tricarboxylic acid cycle, was discovered in the actinomycete corynebacterium glutamicum, a close relative of important human pathogens like corynebacterium diphtheriae and mycobacterium tuberculosis. based on the finding that a c. glutamicum mutant lacking serine/threonine protein kinase g (pkng) was impaired in glutamine utilization, proteome comparisons led to the identifi ... | 2006 | 16522631 |
| mapping and comprehensive analysis of the extracellular and cell surface proteome of the human pathogen corynebacterium diphtheriae. | secreted proteins of the human pathogen corynebacterium diphtheriae might be involved in important pathogen-host cell interactions. here, we present the first systematic reference map of the extracellular and cell surface proteome fractions of the type strain c. diphtheriae c7s(-)tox-. the analysis window of 2-de covered the pi range from 3 to 10 along with a mw range from 8 to 150 kda. computational analysis of the 2-d gels detected almost 150 protein spots in the extracellular proteome fractio ... | 2006 | 16544277 |
| experimental model of infection with non-toxigenic strains of corynebacterium diphtheriae and development of septic arthritis. | corynebacterium diphtheriae is a well-known cause of localized respiratory tract infections. however, this micro-organism can also be associated with invasive infections, such as endocarditis, septic arthritis and osteomyelitis. invasive infections are often caused by non-toxigenic strains. to set up an in vivo experimental model of c. diphtheriae infection, mice were infected intravenously with different doses (ranging from 1 x 10(7) to 5 x 10(8) bacteria per mouse) of three non-toxigenic strai ... | 2006 | 16434717 |
| mn(ii) binding by the anthracis repressor from bacillus anthracis. | the anthracis repressor (antr) is a manganese-activated transcriptional regulator from bacillus anthracis and is a member of the diphtheria toxin repressor (dtxr) family of proteins. in this paper, we characterize the mn(ii) binding and protein dimerization state using a combination of continuous wave (cw) and pulsed epr methods. equilibrium metal binding experiments showed that antr binds 2 equivalents of mn(ii) with positive cooperativity and apparent dissociation constants of 210 and 16.6 mic ... | 2006 | 16566604 |
| in vitro antibacterial, antifungal & cytotoxic activity of some isonicotinoylhydrazide schiff's bases and their cobalt (ii), copper (ii), nickel (ii) and zinc (ii) complexes. | isonicotinoylhydrazide schiff's bases formed by the reaction of substituted and unsubstituted furyl-2-carboxaldehyde and thiophene-2-carboxaldehyde with isoniazid and, their co (ii), cu (ii), ni (ii) and zn (ii) complexes have been synthesized, characterized and screened for their in vitro antibacterial activity against mycobacterium tuberculosis, escherichia coli, klebsiella pneumoniae, proteus mirabilis, pseudomonas aeruginosa, salmonella typhi, shigella dysenteriae, bacillus cereus, corynebac ... | 2006 | 16570512 |
| in vivo effect of carbon dioxide laser-skin resurfacing and mechanical abrasion on the skin's microbial flora in an animal model. | although beam-scanning carbon dioxide (co2) lasers have provided a highly efficient tool for esthetic skin rejuvenation there has been no comprehensive animal studies looking into microbial skin changes following co2 laser skin resurfacing. | 2006 | 16640679 |
| diphtheria vaccine. | 2006 | 16671240 | |
| antidiphtheria antibody responses in patients and carriers of corynebacterium diphtheriae in the arkhangelsk region of russia. | diphtheria is under control in industrialized countries. however, single cases and outbreaks still occur and the disease is not completely understood. forty-three individuals suspected of having diphtheria who were referred to the infectious disease hospital of arkhangelsk from december 1994 to march 1995 were included in this study. fifteen patients were diagnosed as having diphtheria and received equine hyperimmune antidiphtheria toxin antiserum, and 28 were diagnosed as carriers, 12 with nond ... | 2006 | 16760319 |
| modulation of eukaryotic cell apoptosis by members of the bacterial order actinomycetales. | apoptosis, or programmed cell death, is normally responsible for the orderly elimination of aged or damaged cells, and is a necessary part of the homeostasis and development of multicellular organisms. some pathogenic bacteria can disrupt this process by triggering excess apoptosis or by preventing it when appropriate. either event can lead to disease. there has been extensive research into the modulation of host cell death by microorganisms, and several reviews have been published on the phenom ... | 2006 | 16850163 |
| diphtheria-neutralizing antibody levels in healthy adults from rio de janeiro, brazil. | in brazil, until 2004, the immunization policy against diphtheria involved childhood vaccination with no official routine booster dose administered after 15 years of age. this study assessed functional antibody levels against diphtheria among blood donors. a total of 140 blood samples were collected, and diphtheria antitoxin levels were evaluated by vero cell neutralization test. the mean age of the population was 34 years old (range: 18-61 years); 37.8% females and 62.2% males. overall, 30.7% ( ... | 2006 | 16951820 |
| metalloantibiotics: synthesis, characterization and in-vitro antibacterial studies on cobalt (ii), copper (ii), nickel (ii) and zinc (ii) complexes with cloxacillin. | the synthesis and characterization of cloxacillin (clox) complexes with divalent metal ions [co (ii), cu (ii), ni (ii) and zn (ii)] is described. the nature of bonding of the chelated cloxacillin and the structures of the metal complexes have been elucidated on the basis of their physical and spectroscopic data. in all the complexes, the cloxacillin acts as a uninegatively charged bidentate ligand with coordination involving the carboxylate-o and endocyclic-n of the beta-lactam ring. the new com ... | 2006 | 17059178 |
| [modulation of molecular signaling mechanisms in excitable cells by toxins and bacterial substances]. | the mechanisms of bacterial substances (protein a, peptidoglican staphylococcus aureus), bacterium toxins (st. aureus, corynebacterium diphtheriae, shigella dysenteriae, clostridium botulinum, clostridium tetani, vibrio choleral), transfer factor of immune reactivity to staphylococcus aureus upon the key link (acetylcholine-, atp-, inositol-1,4,5-triphosphate-, ryanodin-sensitive receptors, g-proteins, ca2+, k(+)-transporting systems, second messengers) in the chain of signal conduction of excit ... | 2005 | 16566125 |
| [an unusual course of invasive infection due to nontoxinogenic strain of corynebacterium diphtheriae.] | the authors report a case of complicated sepsis caused by nontoxigenic corynebacterium diphtheriae biotype gravis in a young immunocompetent female with no predisposing factors. she acquired the infection from her boyfriend, an asymptomatic carrier of nontoxigenic strain. the primary site of infection and subsequent sepsis was not identified. the occurence and importance of carriage and invasive infections caused by nontoxigenic strains of corynebacterium diphtheriae are discused. | 2005 | 16440286 |
| mechanism of metal ion activation of the diphtheria toxin repressor dtxr. | the diphtheria toxin repressor (dtxr) is a metal ion-activated transcriptional regulator that has been linked to the virulence of corynebacterium diphtheriae. structure determination has shown that there are two metal ion binding sites per repressor monomer, and site-directed mutagenesis has demonstrated that binding site 2 (primary) is essential for recognition of the target dna repressor, leaving the role of binding site 1 (ancillary) unclear. calorimetric techniques have demonstrated that alt ... | 2005 | 16352732 |
| anti-bacterial alkaloids of saracococca saligna. | the crude ethanolic extract of saracococca saligna was found to be cytotoxic and antibacterial but produced no platelet aggregation induced by adp. antibacterial activity of two known alkaloid, pachyaximine-a and saracodine was determined. pachyaximine-a possessed significant antibacterial activity against escherichia coli, staphylococcus aureus, corynebacterium diphtheriae and corynebacterium pyrogenes. saracodme showed moderate activity against staphylococcus pyrogenes, escherichia coli, staph ... | 2005 | 16431389 |
| roles of distal asp in heme oxygenase from corynebacterium diphtheriae, hmuo: a water-driven oxygen activation mechanism. | heme oxygenases found in mammals, plants, and bacteria catalyze degradation of heme using the same mechanism. roles of distal asp (asp-136) residue in hmuo, a heme oxygenase of corynebacterium diphtheriae, have been investigated by site-directed mutagenesis, enzyme kinetics, resonance raman spectroscopy, and x-ray crystallography. replacements of the asp-136 by ala and phe resulted in reduced heme degradation activity due to the formation of ferryl heme, showing that the distal asp is critical i ... | 2005 | 15528205 |
| prolylpeptide binding by the prokaryotic sh3-like domain of the diphtheria toxin repressor: a regulatory switch. | diphtheria toxin repressor (dtxr) regulates the expression of iron-sensitive genes in corynebacterium diphtheriae, including the diphtheria toxin gene. dtxr contains an n-terminal metal- and dna-binding domain that is connected by a proline-rich flexible peptide segment (pr) to a c-terminal src homology 3 (sh3)-like domain. we determined the solution structure of the intramolecular complex formed between the proline-rich segment and the sh3-like domain by use of nmr spectroscopy. the structure o ... | 2005 | 15628844 |
| analysis of a dtxr-regulated iron transport and siderophore biosynthesis gene cluster in corynebacterium diphtheriae. | this report describes a genetic locus associated with siderophore biosynthesis and transport in corynebacterium diphtheriae. a blast search of the c. diphtheriae genome identified a seven-gene cluster that included four genes, designated ciua, ciub, ciuc, and ciud, whose predicted products are related to abc-type iron transporters. downstream from ciud is the ciue gene, whose predicted product is similar to the aerobactin biosynthetic enzymes iuca and iucc. the ciue protein, which has a predicte ... | 2005 | 15629913 |
| the acyl-amp ligase fadd32 and accd4-containing acyl-coa carboxylase are required for the synthesis of mycolic acids and essential for mycobacterial growth: identification of the carboxylation product and determination of the acyl-coa carboxylase components. | mycolic acids are major and specific long-chain fatty acids of the cell envelope of several important human pathogens such as mycobacterium tuberculosis, m. leprae, and corynebacterium diphtheriae. their biosynthesis is essential for mycobacterial growth and represents an attractive target for developing new antituberculous drugs. we have previously shown that the pks13 gene encodes condensase, the enzyme that performs the final condensation step of mycolic acid biosynthesis and is flanked by tw ... | 2005 | 15632194 |
| molecular characterization of diphtheria toxin repressor (dtxr) genes present in nontoxigenic corynebacterium diphtheriae strains isolated in the united kingdom. | nontoxigenic strains of corynebacterium diphtheriae represent a potential reservoir for the emergence of toxigenic c. diphtheriae strains if they possessed functional diphtheria toxin repressor (dtxr) genes. we studied the predominant strain of nontoxigenic c. diphtheriae circulating in the united kingdom to see if they possessed dtxr genes and ascertain whether they were functional. a total of 26 nontoxigenic c. diphtheriae strains isolated in the united kingdom during 1995 and 4 nontoxigenic s ... | 2005 | 15634975 |
| classical diphtheria caused by corynebacterium ulcerans in germany: amino acid sequence differences between diphtheria toxins from corynebacterium diphtheriae and c. ulcerans. | 2005 | 15655760 | |
| novel potentiometric immunosensor for determination of diphtheria antigen based on compound nanoparticles and bilayer two-dimensional sol-gel as matrices. | a novel method for fabrication of a diphtheria potentiometric immunosensor has been developed by means of self-assembling compound nanoparticles to a thiol-containing sol-gel network. a cleaned gold electrode was first immersed in a 3-mercaptopropyltrimethoxysilane (mps) sol-gel solution to assemble a silica sol-gel monolayer. the silane entities were then polymerized into a two-dimensional sol-gel network (2d network) by dipping into aqueous naoh. the second silane layer was formed by re-immers ... | 2005 | 15657709 |
| analysis of truncated variants of the iron dependent transcriptional regulators from corynebacterium diphtheriae and mycobacterium tuberculosis. | iron dependent regulatory proteins of the diphtheria toxin repressor family regulate transcription in a variety of bacterial species. these regulators have three domains. domains 1 and 2 are required for dna- and metal-binding while the role of the third domain is only partially defined. we compared full-length and carboxyl-terminally truncated variants of corynebacterium diphtheriae dtxr and mycobacterium tuberculosis ider for recognition by antibodies, dna binding, and repressor activity. the ... | 2005 | 15667993 |
| cardiac troponin i release in non-ischemic reversible myocardial injury from acute diphtheric myocarditis. | cardiac troponins are highly specific markers of myocardial injury. it has been suggested that, unlike other markers of myocardial injury, troponins could be released in reversible myocardial injury and the myocardial necrosis does not have to occur for troponins to be released from myocytes. reversibly injury related changes in myocyte membrane are considered sufficient for the release of cardiac troponins from the free cytosolic pool, whereas in case of irreversible myocardial injury the sourc ... | 2005 | 15686793 |
| long-term treatment of atopic dermatitis with pimecrolimus cream 1% in infants does not interfere with the development of protective antibodies after vaccination. | we investigated whether treatment of atopic dermatitis with pimecrolimus cream 1% in infants affects the development of a normal antibody response to vaccinations. | 2005 | 15692469 |
| skin ulcers in a returned traveller. | 2005 | 15721480 | |
| imported cutaneous diphtheria, germany, 1997-2003. | 2005 | 15759338 | |
| [specific antibodies and their role in the formation of antidiphtheria immunity]. | in human sera, studied with the use of the enzyme immunoassay, antidiphtheria postvaccinal antitoxic igg and naturally acquired antibacterial igg, igm and iga were detected. in the blood of children and adults aged up to 50 years antitoxic igg were present at normal and high concentrations. in 50% of children antibacterial iga were absent, while specific antibacterial igm could be found at high concentrations. changes in the content of antibacterial antibodies of different classes in sera were o ... | 2005 | 15773398 |
| efficient discrimination within a corynebacterium diphtheriae epidemic clonal group by a novel macroarray-based method. | a large diphtheria epidemic in the 1990s in russia and neighboring countries was caused by a clonal group of closely related corynebacterium diphtheriae strains (ribotypes sankt-peterburg and rossija). in the recently published complete genome sequence of c. diphtheriae strain nctc13129, representative of the epidemic clone (a. m. cerdeno-tarraga et al., nucleic acids res. 31:6516-6523, 2003), we identified in silico two direct repeat (dr) loci 39 kb downstream and 180 kb upstream of the oric re ... | 2005 | 15814981 |
| infections with corynebacterium diphtheriae: six years' experience at an inner london teaching hospital. | recently, a preponderance of non-toxigenic strains of corynebacterium diphtheriae has been reported, as has the broadening spectrum of disease caused by these strains. this study presents data on 85 isolates of c. diphtheriae over a six year period (1998-2003). eighty were non-toxigenic isolates from patients with sore throat, and five (one toxigenic) were from cutaneous ulcers in travellers returning from endemic areas. when examined in relation to denominator data provided by the health protec ... | 2005 | 15816203 |
| the first case of septicemia due to nontoxigenic corynebacterium diphtheriae in poland: case report. | toxigenic strains of corynebacterium diphtheriae are well known agent of diphtheria. nontoxigenic strains can cause atypical course of the disease. invasive diseases caused by c. diphtheriae occur very rare. | 2005 | 15876349 |
| [resistance to a causative agent of infection and immune response]. | an analytical literature review dealing with the problems of resistance to causative agents of infections. the review includes the data of experimental research, as well as the author's own immunological studies in children at the clinic of acute infections. mechanisms of resistance at different phases of the infectious process, the multivalued role of th1- and th2-dependent responses in different infections, the role of vaccinal immunity in the resistance of children to the causative agents of ... | 2005 | 15881954 |
| eagle effect in corynebacterium diphtheriae. | the in vivo relevance of the paradoxical bactericidal effect (the eagle effect) is not evident. we found in vitro a paradoxical bactericidal effect of amoxicillin on 2 strains of nontoxigenic corynebacterium diphtheriae. then, using an experimental rabbit model of endocarditis, we evaluated the in vivo relevance of this phenomenon. rabbits were assigned to the following groups: no treatment (control group), continuous amoxicillin infusion simulating a dosage of 200 mg/kg/day in humans, and conti ... | 2005 | 15897998 |
| immunogenicity of routine vaccination against diphtheria, tetanus, and haemophilus influenzae type b in asian infants born in the united kingdom. | to determine the immunogenicity of routine vaccination against diphtheria, tetanus, and haemophilus influenzae type b (hib) in asian infants born in the uk, and whether maternal antibody suppression occurs. | 2005 | 15908622 |
| in-vitro antibacterial, antifungal and cytotoxic properties of sulfonamide--derived schiff's bases and their metal complexes. | a series of new antibacterial and antifungal schiff's bases derived from sulfonamides, as well as their transition metal complexes incorporating cobalt (ii), copper (ii), nickel (ii) and zinc (ii) were synthesized, characterized and screened for their in-vitro antibacterial activity against six gram-negative (escherichia coli, klebsiella pneumoniae, proteus mirabilis, pseudomonas aeruginosa, salmonella typhi and shigella dysentriae) and four gram-positive (bacillus cereus, corynebacterium diphth ... | 2005 | 15968823 |
| prevalence of fusobacterium necrophorum and other upper respiratory tract pathogens isolated from throat swabs. | fusobacterium necrophorum, an anaerobic, gram-negative rod, has been identified recently as a significant cause of persistent sore throat syndrome (psts). this disease is characterised by chronic, recurrent or persistent sore throat, which is believed to respond poorly to penicillin in vivo. the aim of this study is to examine the prevalence of f. necrophorum in all throat swabs received in our diagnostic microbiology department and to compare the results with those for other recognised respirat ... | 2005 | 15997879 |
| human clinical isolates of corynebacterium diphtheriae and corynebacterium ulcerans collected in canada from 1999 to 2003 but not fitting reporting criteria for cases of diphtheria. | a 5-year collection of corynebacterium diphtheriae and corynebacterium ulcerans human clinical isolates yielded nine isolates from blood cultures of patients with invasive infections, stressing the importance of c. diphtheriae as a serious blood-borne pathogen. seven percent of c. diphtheriae and 100% of c. ulcerans isolates produced diphtheria toxin, demonstrating that toxigenic corynebacteria continue to circulate. | 2005 | 16000474 |
| [immunological tests: corynebacterium diphtheriae, dephtheria toxin]. | 2005 | 16111218 | |
| both corynebacterium diphtheriae dtxr(e175k) and mycobacterium tuberculosis ider(d177k) are dominant positive repressors of ider-regulated genes in m. tuberculosis. | the diphtheria toxin repressor (dtxr) is an important iron-dependent transcriptional regulator of known virulence genes in corynebacterium diphtheriae. the mycobacterial iron-dependent repressor (ider) is phylogenetically closely related to dtxr, with high amino acid similarity in the dna binding and metal ion binding site domains. we have previously shown that an iron-insensitive, dominant-positive dtxr(e175k) mutant allele from corynebacterium diphtheriae can be expressed in mycobacterium tube ... | 2005 | 16113319 |
| the cgl2612 protein from corynebacterium glutamicum is a drug resistance-related transcriptional repressor: structural and functional analysis of a newly identified transcription factor from genomic dna analysis. | the emergence of antibiotic-resistant bacteria often causes serious clinical problems. the tetr family is one of the major transcription factor families that regulate expression of genes involved in bacterial antimicrobial resistance systems. cgl2612 protein is a transcription factor newly identified by genomic dna analysis on corynebacterium glutamicum, which belongs to the mycolic acid-containing actinomycetales, including the well known pathogens corynebacterium diphtheriae and mycobacterium ... | 2005 | 16166084 |
| prevalence of igg diphtheria antitoxin in blood donors in rio de janeiro. | the lack of information on the immunity of adults in brazil against diphtheria prompted us to analyse sera from 234 blood donors aged 18-61 years (30.3% females and 69.7% males). igg diphtheria antitoxin levels determined by means of an elisa, validated by toxin neutralization test in vero cells, showed that 30.7% (95% ci 25.0-37.1) of the population was fully protected (>or=1 iu/ml). the highest percentage of subjects fully protected was in the 31-40 years age group. most of the subjects with u ... | 2005 | 16181513 |
| in-vitro antibacterial, antifungal and cytotoxic activities of some coumarins and their metal complexes. | a series of new antibacterial and antifungal coumarin-derived compounds and their transition metal complexes [cobalt (ii), copper (ii), nickel (ii) and zinc (ii)] have been synthesized, characterized and screened for their in vitro antibacterial activity against escherichia coli, klebsiella pneumoniae, proteus mirabilis, pseudomonas aeruginosa, salmonella typhi, shigella dysenteriae, bacillus cereus, corynebacterium diphtheriae, staphylococcus aureus and streptococcus pyogenes bacterial strains ... | 2005 | 16206827 |
| respiratory diphtheria among highly vaccinated military trainees in latvia: improved protection from dt compared with td booster vaccination. | an outbreak of respiratory diphtheria occurred among highly-vaccinated trainees at a latvian military academy in august-september 2000. we reviewed immunization, clinical and laboratory records and administered a questionnaire to obtain data on exposure factors. among 207 trainees, 45 (22%) diphtheria cases and 79 (38%) carriers of toxigenic corynebacterium diphtheriae were identified. all patients survived; 1 had severe myocarditis. sharing cups was a risk factor for infection. over 85% of trai ... | 2005 | 16308214 |
| in-vitro antibacterial and cytotoxic activity of cobalt (ii), copper (ii), nickel (ii) and zinc (ii) complexes of the antibiotic drug cephalothin (keflin). | keflin (kefl) interacts with co(ii), cu(ii), ni(ii) and zn(ii) metal ions leading to complexes of the type m(kefl)2cl2 and m(kefl)cl2, which have been characterized by physicochemical and spectroscopic methods. magnetic moment, ir, electronic spectral and elemental analyses data suggest that keflin behaves tridentately forming octahedral or trigonal bipyramidal complexes with the metal ions mentioned above. the new compounds have been screened in-vitro for antibacterial and cytotoxic activity ag ... | 2005 | 16335054 |
| sequence of ligand binding and structure change in the diphtheria toxin repressor upon activation by divalent transition metals. | the diphtheria toxin repressor (dtxr) is an fe(ii)-activated transcriptional regulator of iron homeostatic and virulence genes in corynebacterium diphtheriae. dtxr is a two-domain protein that contains two structurally and functionally distinct metal binding sites. here, we investigate the molecular steps associated with activation by ni(ii)cl(2) and cd(ii)cl(2). equilibrium binding energetics for ni(ii) were obtained from isothermal titration calorimetry, indicating apparent metal dissociation ... | 2005 | 15823025 |
| analysis of a heme-dependent signal transduction system in corynebacterium diphtheriae: deletion of the chras genes results in heme sensitivity and diminished heme-dependent activation of the hmuo promoter. | the corynebacterium diphtheriae hmuo gene encodes a heme oxygenase that is involved in the utilization of heme as an iron source. transcription of hmuo is activated by heme or hemoglobin and repressed by iron and dtxr. previous studies with escherichia coli showed that heme-dependent transcriptional activation of an hmuo promoter-lacz fusion was dependent on the cloned c. diphtheriae chra and chrs genes (chras), which encode the response regulator and sensor kinase, respectively, of a two-compon ... | 2005 | 16239540 |
| [characteristics of the antitoxic and antibacterial immune response in children with diphtheria]. | as found in this study, the development of the manifest forms of diphtheria occurred in the presence of lower levels of antitoxic antibodies, than bacterial carrier state. the level of antitoxic antibodies in all patients, irrespective of the time of their examination, was higher than that of antibacterial antibodies. in the dynamics of the disease a considerable increase in antitoxic and antibacterial antibodies was observed in localized and disseminated forms of diphtheria and, to a considerab ... | 2005 | 16146229 |
| microbiological analysis of chronic dacryocystitis. | to investigate the microbiology of specimens from patients with chronic dacryocystitis. | 2005 | 15854074 |