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a potent brucella abortus 2308 δery live vaccine allows for the differentiation between natural and vaccinated infection.brucellosis is a globally distributed zoonotic disease that causes animal and human diseases. however, the current brucella abortus vaccines (s19 and rb51) are deficient; they can cause abortion in pregnant animals. moreover, when the vaccine s19 is used, tests cannot differentiate natural from vaccinated infection. therefore, a safer and more potent vaccine is needed. a brucella abortus 2308 ery promoter mutant (δery) was constructed to overcome these drawbacks. the growth of the δery mutant wa ...201424994009
advancement of knowledge of brucella over the past 50 years.fifty years ago, bacteria in the genus brucella were known to cause infertility and reproductive losses. at that time, the genus was considered to contain only 3 species: brucella abortus, brucella melitensis, and brucella suis. since the early 1960s, at least 7 new species have been identified as belonging to the brucella genus (brucella canis, brucella ceti, brucella inopinata, brucella microti, brucella neotomae, brucella ovis, and brucella pinnipedialis) with several additional new species u ...201424981716
proteomic analyses of the time course responses of mice infected with brucella abortus 544 reveal immunogenic antigens.brucellosis is a major zoonotic disease caused by pathogens of the genus brucella. the eradication of brucellosis in domestic animals, associated with the prevention of human infection, can be attained through accurate diagnosis. however, the conventional serological diagnosis of brucellosis has limitations, particularly in detecting the infection period. accordingly, the aim of this study was to determine reliable immunogenic proteins to detect brucella abortus infection according to time cours ...201424975114
evaluation of immunogenicity and protective efficacy of a plasmid dna vaccine encoding ribosomal protein l9 of brucella abortus in balb/c mice.brucellosis is a worldwide zoonotic disease. no brucella vaccine is available for use in humans and existing animal vaccines have limitations. we have previously described the ribosomal protein l9 to have the vaccine potential. in this study, l9 based dna vaccine (pvaxl9) was generated and evaluated in mouse model. intramuscular immunisation of pvaxl9 was able to elicit the anti-l9 igg antibody response of both igg1 and igg2a isotypes when compared with pbs and pvax immunised control animals. he ...201424950353
a repa-based elisa for discriminating cattle vaccinated with brucella suis 2 from those naturally infected with brucella abortus and brucella melitensis.the commonest ways of diagnosing brucellosis in animals include the rose-bengal plate agglutination test, the buffered plate agglutination test (bpa), the slide agglutination test, the complement fixation test, and the indirect enzyme linked immunosorbent assay (i-elisa). however, these methods cannot discriminate the brucella vaccine strain (brucella suis strain 2; b. suis s2) from naturally acquired virulent strains. of the six common brucella species, brucella melitensis, brucella abortus, an ...201424941369
roles of genomic island 3 (gi-3) bab1_0267 and bab1_0270 open reading frames (orfs) in the virulence of brucella abortus 2308.one of the properties of bacteria is their capacity to acquire large fragments of genomic dna from other bacteria or to loose important parts of their own genome. such fragments include genomic islands (gis); nine gis are present in brucella, including genomic island 3 (gi-3), present in b. abortus, b. melitensis and b. ovis. the gi-3 have 29 open reading frames (orfs) most of them with unknown function. within the gi-3, the orfs bab1_0267 encodes a hypothetical protein sharing a sh3 domain and ...201424928771
the identification of wadb, a new glycosyltransferase gene, confirms the branched structure and the role in virulence of the lipopolysaccharide core of brucella abortus.brucellosis is a worldwide extended zoonosis caused by brucella spp. these gram-negative bacteria are not readily detected by innate immunity, a virulence-related property largely linked to their surface lipopolysaccharide (lps). the role of the lps lipid a and o-polysaccharide in virulence is well known. moreover, mutation of the glycosyltransferase gene wadc of brucella abortus, although not affecting o-polysaccharide assembly onto the lipid-a core section causes a core oligosaccharide defect ...201424927935
immunoproteomics of brucella abortus rb51 as candidate antigens in serological diagnosis of brucellosis.the current brucellosis serodiagnostic assays are chiefly based on detecting anti-lps (lipopolysaccharide) antibodies. however, cross-reaction with some gram-negative bacteria can occasionally induce due to similar o-polysaccharide (ops) structure. therefore, the aim of the present study was to identify new candidate antigens from brucella abortus rb51, a mutant strain lacking the lps portion, which might be valuable in brucellosis diagnosis. to detect potential antigens, immobilized ph gradient ...201424908638
polymorphisms at the 3' untranslated region of slc11a1 gene are associated with protection to brucella infection in goats.goats are susceptible to brucellosis and the detection of brucella-infected animals is carried out by serological tests. in other ruminant species, polymorphisms in microsatellites (ms) of 3' untranslated region (3'utr) of the solute carrier family 11 member a1 (slc11a1) gene were associated with resistance to brucella abortus infection. goats present two polymorphic ms at the 3'utr end of slc11a1 gene, called regions a and b. here, we evaluated if polymorphisms in regions a and/or b are associa ...201424906349
serological survey of brucella canis in dogs in urban harare and selected rural communities in zimbabwe.a cross-sectional study was conducted in order to detect antibodies for brucella canis (b. canis) in dogs from urban harare and five selected rural communities in zimbabwe. sera from randomly selected dogs were tested for antibodies to b. canis using an enzyme-linked immunosorbent assay. overall, 17.6% of sera samples tested (57/324, 95% ci: 13.5-21.7) were positive for b. canis antibodies. for rural dogs, seroprevalence varied from 11.7% - 37.9%. rural dogs recorded a higher seroprevalence (20. ...201424830899
innate immune sensing of nucleic acids from pathogens.the innate immune system is important as the first line of defense to sense invading pathogens. nucleic acids represent critical pathogen signatures that trigger a host proinflammatory immune response. much progress has been made in understanding how dna and rna trigger host defense countermeasures, however, several aspects of how cytosolic nucleic acids are sensed remain unclear. this special issue reviews how the host innate immune system senses nucleic acids from brucella abortus, mycobacteri ...201425449751
seroprevalence of brucellosis in sheep and isolation of brucella abortus biovar 6 in kassala state, eastern sudan.brucellosis is one of the important zoonotic diseases among livestock. this study was carried out to estimate the prevalence of brucellosis and isolate brucella spp. in sheep in kassala state in the east of sudan. two thousand and five serum samples were randomly collected from nine different localities. all serum samples were examined by the rose bengal plate test (rbpt) and the modified rbpt (mrbpt). forty-three (2.15%, 95% confidence interval [ci]: 1.6,3.0) and 68 (3.4%, 95% ci: 2.6, 4.2) sam ...201425812219
isolation and identification of bovine brucella isolates from pakistan by biochemical tests and pcr.brucellosis is endemic in bovines in pakistan. the brucella species and biovars involved, however, are unknown. the objectives of the present study were to isolate and characterize brucellae from seropositive milk samples, aborted fetuses, and vaginal swabs of cattle and buffaloes which had recently aborted. the seropositive milk samples, aborted fetuses, and vaginal swabs of cattle and buffaloes were collected from the potohar plateau, pakistan. isolation of brucellae was done on modified farre ...201423868548
¹³c, ¹⁵n and ¹h backbone and side chain chemical shift assignment of acid-stress bacterial chaperone hdea at ph 6.hdea is a small chaperone found in the periplasm of several common pathogenic bacteria (escherichia coli, shigella flexneri and brucella abortus) which are the leading causes of dysentery worldwide, especially in developing countries. its job is to protect other periplasmic proteins from aggregating as the bacteria pass through the low ph environment of the human stomach on their way to infect the intestines. hdea is an inactive folded dimer at neutral ph, but becomes a disordered active monomer ...201423835624
seroprevalence for coxiella burnetii, francisella tularensis, brucella abortus and brucella melitensis in austrian adults: a cross-sectional survey among military personnel and civilians.the prevalence of coxiella burnetii, francisella tularensis, brucella abortus, and brucella melitensis infections in austria and the exposure risk of military personnel were assessed in an exploratory nationwide cross-sectional seroprevalence survey in 526 healthy adult individuals, 222 of which were soldiers and 304 were civilians. screening for iga/igg antibodies to c. burnetii (phase i) and igg/igm antibodies to c. burnetii (phase ii), and to f. tularensis was done with commercial enzyme-link ...201424572607
the influence of genetic background versus commercial breeding programs on chicken immunocompetence.immunocompetence of livestock plays an important role in farm profitability because it directly affects health maintenance. genetics significantly influences the immune system, and the genotypic structure of modern fast-growing chickens has been changed, particularly after decades of breeding for higher production. therefore, this study was designed to help determine if intensive breeding programs have adversely affected immunocompetence or whether the immune response profiles are controlled to ...201424570426
feasibility of quarantine procedures for bison (bison bison) calves from yellowstone national park for conservation of brucellosis-free bison.objective--to determine the feasibility of qualifying individuals or groups of yellowstone national park bison as free from brucellosis. design--cohort study. sample--serum, blood, and various samples from live bison and tissues taken at necropsy from 214 bison over 7 years. procedures--blood was collected from bison every 30 to 45 days for serologic tests and microbiological culture of blood for brucella abortus. seropositive bison were euthanized until all remaining bison had 2 consecutive neg ...201424548234
comparative whole genome analysis of six diagnostic brucellaphages.whole genome sequencing of six diagnostic brucellaphages, tbilisi (tb), firenze (fz), weybridge (wb), s708, berkeley (bk) and r/c, was followed with genomic comparisons including recently described genomes of the tb phage from mexico (tbm) and pr phage to elucidate genomic diversity and candidate host range determinants. comparative whole genome analysis revealed high sequence homogeneity among these brucellaphage genomes and resolved three genetic groups consistent with defined host range pheno ...201424530704
comparative proteomics analysis of host cells infected with brucella abortus a19.we carried out a proteomic analysis of thp-1-derived macrophages with and without brucella abortus a19 (b. abortus a19) infection in order to study the cellular responses to b. abortus a19. the proteins were analyzed at different time points after infection with 2de followed by maldi-tof/tof identification. comparative analysis of multiple 2de gels revealed that the majority of changes in protein abundance appeared between 48 and 96 h after infection. ms identified 44 altered proteins, including ...201424519676
a comparative assessment of culture and serology in the diagnosis of brucellosis in dairy cattle.to investigate the usefulness of culture for the confirmation of brucellosis in cattle, a comparison of culture and serology was undertaken on 248 animals in four dairy herds where the disease was active. paired supramammary (sm), retropharyngeal (rp), and internal iliac (il) lymph nodes were cultured, and five serological tests were deployed: the microserum agglutination test (msat), complement fixation test (cft), the indirect (ielisa) and competitive elisa, and the fluorescence polarisation a ...201424507882
outbreak of laboratory-acquired brucella abortus in brazil: a case report.human brucellosis is an occupational disease affecting workers in slaughterhouses, butcher shops and the milk and dairy product industry as well as individuals who work in clinical or research laboratories. we report the first outbreak of a brucella abortus infection in a brazilian laboratory and compare the data obtained with reports available in the literature. exposure was a result of damage to a biological safety cabinet and failure of the unidirectional airflow ventilation system. an epidem ...201424474027
urocanate as a potential signaling molecule for bacterial recognition of eukaryotic hosts.host recognition is the crucial first step in infectious disease pathogenesis. recognition allows pathogenic bacteria to identify suitable niches and deploy appropriate phenotypes for successful colonization and immune evasion. however, the mechanisms underlying host recognition remain largely unknown. mounting evidence suggests that urocanate-an intermediate of the histidine degradation pathway-accumulates in tissues, such as skin, and acts as a molecule that promotes bacterial infection via mo ...201424305948
immunogenic response induced by wzm and wzt gene deletion mutants from brucella abortus s19.brucellosis is an infectious disease affecting humans and animals worldwide. effective methods of control include inducing immunity in animals by vaccination and elimination. brucella abortus s19 is one of the popular vaccines for control of cattle brucellosis, as it has low virulence. in this paper, allelic exchange plasmids of wzm and wzt genes were constructed and partially knocked out to evaluate the effects on the induction of immunity to brucella abortus s19 mutants. cytokine secretion in ...201424247358
serological survey and risk factors for brucellosis in water buffaloes in the state of pará, brazil.to evaluate the prevalence and possible risk factors for brucellosis caused by brucella abortus in water buffaloes in the state of pará, brazil, 3,917 female buffalo serum samples from pregnant and non-pregnant animals were examined: 2,809 from marajó island and 1,108 from the mainland. the buffered acidified plate antigen (bapa) screening test positively diagnosed 4.8% (188/3,917) of the animals with brucellosis, and the 2-mercaptoethanol (2-me) confirmatory test affirmed 95.7% (180/188) of the ...201424221991
characterization of betaine aldehyde dehydrogenase (betb) as an essential virulence factor of brucella abortus.the pathogenic mechanisms of brucellosis used to adapt to the harsh intracellular environment of the host cell are not fully understood. the present study investigated the in vitro and in vivo characteristics of b. abortus betaine aldehyde dehydrogenase (betb) (gene bank id: 006932) using a betb deletion mutant constructed from virulent b. abortus 544. in test under stress conditions, including osmotic- and acid stress-resistance, the betb mutant had a lower osmotic-resistance than b. abortus wi ...201424210811
infection of c57bl/6 mice by trypanosoma musculi modulates host immune responses during brucella abortus cocolonization.brucellosis, which results in fetal abortions in domestic and wildlife animal populations, is of major concern in the us and throughout much of the world. the disease, caused by brucella abortus, poses an economic threat to agriculture-based communities. a moderately efficacious live attenuated vaccine (b. abortus strain rb51) exists. however, even with vaccine use, outbreaks occur. evidence suggests that elk (cervus canadensis), a wild host reservoir, are the source of recent outbreaks in domes ...201424171573
improved immunogenicity of tetanus toxoid by brucella abortus s19 lps adjuvant.adjuvants are used to increase the immunogenicity of new generation vaccines, especially those based on recombinant proteins. despite immunostimulatory properties, the use of bacterial lipopolysaccharide (lps) as an adjuvant has been hampered due to its toxicity and pyrogenicity. brucella abortus lps is less toxic and has no pyrogenic properties compared to lps from other gram negative bacteria.201425266004
on the link between cell cycle and infection of the alphaproteobacterium brucella abortus.bacteria of the brucella genus are responsible for brucellosis, a worldwide zoonosis. these bacteria are known to have a peculiar intracellular trafficking, with a first long and non-proliferative endosomal stage and a second proliferation stage, often associated with its localization of the bacteria in the endoplasmic reticulum (er). however, the status of the bacterial cell cycle during the non-proliferative phase was still unknown. in a recent study [nat. communic. 5:4366], we followed the ce ...201428357212
brucella infection inhibits macrophages apoptosis via nedd4-dependent degradation of calpain2.the calcium-dependent protease calpain2 is involved in macrophages apoptosis. brucella infection-induced up-regulation of intracellular calcium level is an essential factor for the intracellular survival of brucella within macrophages. here, we hypothesize that calcium-dependent e3 ubiquitin ligase nedd4 ubiquitinates calpain2 and inhibits brucella infection-induced macrophage apoptosis via degradation of calpain2.our results reveal that brucella infection induces increases in nedd4 activity in ...201425258171
loop-mediated isothermal amplification (lamp) test for specific and rapid detection of brucella abortus in cattle.brucella abortus, the major causative agent of abortion in cattle and a zoonotic pathogen, needs to be diagnosed at an early stage. loop-mediated isothermal amplification (lamp) test is easy to perform and also promising to be adapted at field level.201425220872
novel vector vaccine against brucella abortus based on influenza a viruses expressing brucella l7/l12 or omp16 proteins: evaluation of protection in pregnant heifers.the present study provides the first information about the protection of a novel influenza viral vector vaccine expressing the brucella proteins ribosomal l7/l12 or omp16 containing the adjuvant montanide gel01 in pregnant heifers. immunization of pregnant heifers was conducted via the conjunctival (n=10) or subcutaneous (n=10) route using cross prime and booster vaccination schedules at an interval of 28 days. the vector vaccine was evaluated in comparison with positive control groups vaccinate ...201425218295
t lymphocytes subsets and cytokine pattern induced by vaccination against bovine brucellosis employing s19 calfhood vaccination and adult rb51 revaccination.the aims of this study were to address the protective immune response induced by s19 vaccination (n=10) and rb51 revaccination, in pregnant (n=9) and non-pregnant (n=10) s19 calfhood-vaccinated cattle as follows: evaluate the in vitro cd4(+) and cd8(+) t-lymphocytes specific proliferation, and in vitro expression of ifn-γ by cd4(+) and cd8(+) t-cells and il-4 by cd4(+), cd8(+) and cd21(+) lymphocytes subset. upon in vitro stimulation with γ-irradiated brucella abortus 2308, blood mononuclear cel ...201425218192
characterization of the immunogenicity and pathogenicity of malate dehydrogenase in brucella abortus.brucella abortus is a gram-negative, facultative intracellular pathogen that causes brucellosis, a chronic zoonotic disease resulting in abortion in pregnant cattle and undulant fever in humans. malate dehydrogenase (mdh), a key enzyme in the tricarboxylic acid cycle, plays important metabolic roles in aerobic energy producing pathways and in malate shuttle. in this study, the mdh-encoding gene for malate dehydrogenase mdh of b. abortus s2308 was cloned, sequenced and expressed. western blot ana ...201424609497
induction of immune responses by two recombinant proteins of brucella abortus, outer membrane proteins 2b porin and cu/zn superoxide dismutase, in mouse model.the diagnosis of brucella abortus is mainly based on serological methods using antibody against lps, which has diagnostic problems. therefore, to solve this problem, we evaluated two proteins of b. abortus, cu/zn superoxide dismutase (sodc) and outer membrane proteins 2b porin (omp2b). the genes were cloned and expressed in a pmal system, and the recombinant proteins, romp2b and rsodc, were purified as fusion forms with maltosebinding protein. the identity of the proteins was confirmed by sds-pa ...201424608566
novel influenza virus vectors expressing brucella l7/l12 or omp16 proteins in cattle induced a strong t-cell immune response, as well as high protectiveness against b. abortus infection.this paper presents the results of a study of the immunogenicity and protectiveness of new candidate vector vaccine against brucella abortus - a bivalent vaccine formulation consisting of a mixture of recombinant influenza a subtype h5n1 or h1n1 (viral constructs vaccine formulation) viruses expressing brucella ribosomal protein l7/l12 and omp16, in cattle. to increase the effectiveness of the candidate vaccine, adjuvants such as montanide gel01 or chitosan were included in its composition. immu ...201424598723
effects of partial deletion of the wzm and wzt genes on lipopolysaccharide synthesis and virulence of brucella abortus s19.brucellosis is a worldwide human and animal infectious disease, and the effective methods of its control are immunisation of animals by vaccination and elimination. brucella abortus s19 is one of the popular vaccines with virulence in the control of cattle brucellosis. in the present study, allelic exchange plasmids of wzm and wzt genes and partial knockout mutants of wzm and wzt were constructed to evaluate the resulting difference in virulence of b. abortus s19. pcr analysis revealed that the ...201424718931
serological survey of <i>brucella canis</i> in dogs in urban harare and selected rural communities in zimbabwe.a cross-sectional study was conducted in order to detect antibodies for brucella canis (b. canis) in dogs from urban harare and five selected rural communities in zimbabwe. sera from randomly selected dogs were tested for antibodies to b. canis using an enzyme-linked immunosorbent assay. overall, 17.6% of sera samples tested (57/324, 95% ci: 13.5-21.7) were positive for b. canis antibodies. for rural dogs, seroprevalence varied from 11.7% - 37.9%. rural dogs recorded a higher seroprevalence (20. ...201428235300
integrating population- and individual-level information in a movement model of yellowstone bison.throughout the world, fragmentation of landscapes by human activities has constrained the opportunity for large herbivores to migrate. conflict between people and wildlife results when migrating animals transmit disease to livestock, damage property, and threaten human safety. mitigating this conflict requires understanding the forces that shape migration patterns. bison bos bison migrating from yellowstone national park into the state of montana during winter and spring concern ranchers on land ...201424689146
identification of novel srnas in brucella abortus 2308.involved in diverse biological processes, bacterial srnas are novel regulators of gene expression involved in a wide array of biological processes. to identify srnas in brucella abortus, we performed a genome-wide computational prediction with integrated sipht and napp results. in total, 129 srna candidates were identified, of which 112 were novel srna. twenty novel srna candidates were tested by rt-pcr and seven could be verified. the putative targets of these srnas were also predicted and veri ...201424673258
pathogens in water deer (hydropotes inermis) in south korea, 2010-12.water deer (hydropotes inermis) are among the most common wildlife to approach farmhouses and livestock barns in korea. we collected 305 water deer from gangwon (n=168), south chungcheong (n=89), and gyeongsang (n=48) provinces in 2010-12 and used pcr and serologic tests to screen the deer for pathogens. in 2010, tests for bovine viral diarrhea virus (bvdv), rotavirus, and brucella abortus were positive in 8% (5/60), 2% (1/60), and 59% (33/56) of the animals, respectively. in 2010, the water dee ...201424779466
abortion in cattle due to infection with staphylococcus lugdunensis.an aborted fetus of 7 months gestation, the associated placenta, and a single blood sample from the dam were submitted for diagnostic investigation to the diagnostic laboratory of the lombardy and emilia-romagna experimental zooprophylactic institute in parma, italy. the serum was negative for neospora caninum, coxiella burnetii, chlamydophila abortus, bovine herpesvirus 1 (bhv-1), bovine viral diarrhea virus (bvdv), brucella abortus, and brucella melitensis. fetal tissues and placental cotyledo ...201425292193
immune responses in neonates.neonates have little immunological memory and a developing immune system, which increases their vulnerability to infectious agents. recent advances in the understanding of neonatal immunity indicate that both innate and adaptive responses are dependent on precursor frequency of lymphocytes, antigenic dose and mode of exposure. studies in neonatal mouse models and human umbilical cord blood cells demonstrate the capability of neonatal immune cells to produce immune responses similar to adults in ...201425088080
selective microbial genomic dna isolation using restriction endonucleases.to improve the metagenomic analysis of complex microbiomes, we have repurposed restriction endonucleases as methyl specific dna binding proteins. as an example, we use dpni immobilized on magnetic beads. the ten minute extraction technique allows specific binding of genomes containing the dpni gm6atc motif common in the genomic dna of many bacteria including γ-proteobacteria. using synthetic genome mixtures, we demonstrate 80% recovery of escherichia coli genomic dna even when only femtogram qua ...201425279840
code blue: acinetobacter baumannii, a nosocomial pathogen with a role in the oral cavity.actinetobacter baumannii is an important nosocomial pathogen that can cause a wide range of serious conditions including pneumonia, meningitis, necrotizing fasciitis and sepsis. it is also a major cause of wound infections in military personnel injured during the conflicts in afghanistan and iraq, leading to its popular nickname of 'iraqibacter'. contributing to its success in clinical settings is resistance to environmental stresses such as desiccation and disinfectants. moreover, in recent yea ...201425052812
code blue: acinetobacter baumannii, a nosocomial pathogen with a role in the oral cavity.actinetobacter baumannii is an important nosocomial pathogen that can cause a wide range of serious conditions including pneumonia, meningitis, necrotizing fasciitis and sepsis. it is also a major cause of wound infections in military personnel injured during the conflicts in afghanistan and iraq, leading to its popular nickname of 'iraqibacter'. contributing to its success in clinical settings is resistance to environmental stresses such as desiccation and disinfectants. moreover, in recent yea ...201425052812
microbial peptidyl-prolyl cis/trans isomerases (ppiases): virulence factors and potential alternative drug targets.initially discovered in the context of immunomodulation, peptidyl-prolyl cis/trans isomerases (ppiases) were soon identified as enzymes catalyzing the rate-limiting protein folding step at peptidyl bonds preceding proline residues. intense searches revealed that ppiases are a superfamily of proteins consisting of three structurally distinguishable families with representatives in every described species of prokaryote and eukaryote and, recently, even in some giant viruses. despite the clear-cut ...201425184565
polyphasic analysis of a middle ages coprolite microbiota, belgium.paleomicrobiological investigations of a 14(th)-century coprolite found inside a barrel in namur, belgium were done using microscopy, a culture-dependent approach and metagenomics. results were confirmed by ad hoc pcr--sequencing. investigations yielded evidence for flora from ancient environment preserved inside the coprolite, indicated by microscopic observation of amoebal cysts, plant fibers, seeds, pollens and mold remains. seventeen different bacterial species were cultured from the coproli ...201424586319
kdo2 -lipid a: structural diversity and impact on immunopharmacology.3-deoxy-d-manno-octulosonic acid-lipid a (kdo2 -lipid a) is the essential component of lipopolysaccharide in most gram-negative bacteria and the minimal structural component to sustain bacterial viability. it serves as the active component of lipopolysaccharide to stimulate potent host immune responses through the complex of toll-like-receptor 4 (tlr4) and myeloid differentiation protein 2. the entire biosynthetic pathway of escherichia coli kdo2 -lipid a has been elucidated and the nine enzymes ...201424838025
kdo2 -lipid a: structural diversity and impact on immunopharmacology.3-deoxy-d-manno-octulosonic acid-lipid a (kdo2 -lipid a) is the essential component of lipopolysaccharide in most gram-negative bacteria and the minimal structural component to sustain bacterial viability. it serves as the active component of lipopolysaccharide to stimulate potent host immune responses through the complex of toll-like-receptor 4 (tlr4) and myeloid differentiation protein 2. the entire biosynthetic pathway of escherichia coli kdo2 -lipid a has been elucidated and the nine enzymes ...201424838025
haemophilus ducreyi hfq contributes to virulence gene regulation as cells enter stationary phase.to adapt to stresses encountered in stationary phase, gram-negative bacteria utilize the alternative sigma factor rpos. however, some species lack rpos; thus, it is unclear how stationary-phase adaptation is regulated in these organisms. here we defined the growth-phase-dependent transcriptomes of haemophilus ducreyi, which lacks an rpos homolog. compared to mid-log-phase organisms, cells harvested from the stationary phase upregulated genes encoding several virulence determinants and a homolog ...201424520065
ehrlichia chaffeensis proliferation begins with ntry/ntrx and puta/glna upregulation and ctra degradation induced by proline and glutamine uptake.how the obligatory intracellular bacterium ehrlichia chaffeensis begins to replicate upon entry into human monocytes is poorly understood. here, we examined the potential role of amino acids in initiating intracellular replication. puta converts proline to glutamate, and glna converts glutamate to glutamine. e. chaffeensis puta and glna complemented escherichia coli puta and glna mutants. methionine sulfoximine, a glutamine synthetase inhibitor, inhibited e. chaffeensis glna activity and e. chaf ...201425425236
occurrence of an unusual hopanoid-containing lipid a among lipopolysaccharides from bradyrhizobium species.the chemical structures of the unusual hopanoid-containing lipid a samples of the lipopolysaccharides (lps) from three strains of bradyrhizobium (slow-growing rhizobia) have been established. they differed considerably from other gram-negative bacteria in regards to the backbone structure, the number of ester-linked long chain hydroxylated fatty acids, as well as the presence of a tertiary residue that consisted of at least one molecule of carboxyl-bacteriohopanediol or its 2-methyl derivative. ...201425371196
in depth analysis of the helicobacter pylori cag pathogenicity island transcriptional responses.the severity of symptoms elicited by the widespread human pathogen helicobacter pylori is strongly influenced by the genetic diversity of the infecting strain. among the most important pathogen factors that carry an increased risk for gastric cancer are specific genotypes of the cag pathogenicity island (cag-pai), encoding a type iv secretion system (t4ss) responsible for the translocation of the caga effector oncoprotein. to date, little is known about the regulatory events important for the ex ...201424892739
a bacterial iron exporter for maintenance of iron homeostasis.nutritional iron acquisition by bacteria is well described, but almost nothing is known about bacterial iron export even though it is likely to be an important homeostatic mechanism. here, we show that bradyrhizobium japonicum mbfa (blr7895) is an inner membrane protein expressed in cells specifically under high iron conditions. mbfa contains an n-terminal ferritin-like domain (fld) and a c-terminal domain homologous to the eukaryotic vacuolar membrane fe(2+)/mn(2+) transporter ccc1. an mbfa del ...201424782310
riboregulation in plant-associated α-proteobacteria.the symbiotic α-rhizobia sinorhizobium meliloti, bradyrhizobium japonicum, rhizobium etli and the related plant pathogen agrobacterium tumefaciens are important model organisms for studying plant-microbe interactions. these metabolically versatile soil bacteria are characterized by complex lifestyles and large genomes. here we summarize the recent knowledge on their small non-coding rnas (srnas) including conservation, function, and interaction of the srnas with the rna chaperone hfq. in each of ...201425003187
genome sequencing and annotation of afipia septicemium strain ohsu_ii.we report the 5.1 mb noncontiguous draft genome of afipia septicemium strain ohsu_ii, isolated from blood of a female patient. the genome consists of 5,087,893 bp circular chromosome with no identifiable autonomous plasmid with a g + c content of 61.09% and contains 4898 protein-coding genes and 49 rna genes including 3 rrna genes and 46 trna genes.201425396117
the functions of dna methylation by ccrm in caulobacter crescentus: a global approach.dna methylation is involved in a diversity of processes in bacteria, including maintenance of genome integrity and regulation of gene expression. here, using caulobacter crescentus as a model, we exploit genome-wide experimental methods to uncover the functions of ccrm, a dna methyltransferase conserved in most alphaproteobacteria. using single molecule sequencing, we provide evidence that most ccrm target motifs (gantc) switch from a fully methylated to a hemi-methylated state when they are rep ...201424398711
case report: brucella induced guillain-barré syndrome.neurobrucellosis is relatively uncommon. in a prospective study of 530 patients with brucellosis, neurologic involvement was reported in only 1.7% of the patients. unlike campylobacter jejuni, the commonest infection implicated in guillain-barré syndrome, there are very few reports in the literature of guillain-barré syndrome in association with brucellosis. out of 1,028 cases of brucellosis, polyneuritis was reported in only 2 out of 58 patients with neurological involvement.201425266352
hijacking bacterial glycosylation for the production of glycoconjugates, from vaccines to humanised glycoproteins.glycosylation or the modification of a cellular component with a carbohydrate moiety has been demonstrated in all three domains of life as a basic post-translational process important in a range of biological processes. this review will focus on the latest studies attempting to exploit bacterial n-linked protein glycosylation for glycobiotechnological applications including glycoconjugate vaccine and humanised glycoprotein production. the challenges that remain for these approaches to reach full ...201425244672
hijacking bacterial glycosylation for the production of glycoconjugates, from vaccines to humanised glycoproteins.glycosylation or the modification of a cellular component with a carbohydrate moiety has been demonstrated in all three domains of life as a basic post-translational process important in a range of biological processes. this review will focus on the latest studies attempting to exploit bacterial n-linked protein glycosylation for glycobiotechnological applications including glycoconjugate vaccine and humanised glycoprotein production. the challenges that remain for these approaches to reach full ...201425244672
new closed tube loop mediated isothermal amplification assay for prevention of product cross-contamination.loop mediated isothermal amplification (lamp) assay, a promising diagnostic test, has been developed for detection of different pathogens of human as well as animals. various positive points support its use as a field level test but the major problem is product cross contamination leading to false positive results. different methods were adopted by various researchers to control this false positive amplification due to cross contamination but all have their own advantages and disadvantages. a ne ...201426150945
the yersinia pestis siderophore, yersiniabactin, and the znuabc system both contribute to zinc acquisition and the development of lethal septicaemic plague in mice.bacterial pathogens must overcome host sequestration of zinc (zn(2+) ), an essential micronutrient, during the infectious disease process. while the mechanisms to acquire chelated zn(2+) by bacteria are largely undefined, many pathogens rely upon the znuabc family of abc transporters. here we show that in yersinia pestis, irp2, a gene encoding the synthetase (hmwp2) for the siderophore yersiniabactin (ybt) is required for growth under zn(2+) -deficient conditions in a strain lacking znuabc. more ...201424979062
the importance of proteins of the rnase ii/rnb-family in pathogenic bacteria. 201424918089
bacterial factors exploit eukaryotic rho gtpase signaling cascades to promote invasion and proliferation within their host.actin cytoskeleton is a main target of many bacterial pathogens. among the multiple regulation steps of the actin cytoskeleton, bacterial factors interact preferentially with rhogtpases. pathogens secrete either toxins which diffuse in the surrounding environment, or directly inject virulence factors into target cells. bacterial toxins, which interfere with rhogtpases, and to some extent with rasgtpases, catalyze a covalent modification (adpribosylation, glucosylation, deamidation, adenylation, ...201425203748
dna methylation.the dna of escherichia coli contains 19,120 6-methyladenines and 12,045 5-methylcytosines in addition to the four regular bases, and these are formed by the postreplicative action of three dna methyltransferases. the majority of the methylated bases are formed by the dam and dcm methyltransferases encoded by the dam (dna adenine methyltransferase) and dcm (dna cytosine methyltransferase) genes. although not essential, dam methylation is important for strand discrimination during the repair of re ...201426442938
clinical detection of human probiotics and human pathogenic bacteria by using a novel high-throughput platform based on next generation sequencing.the human body plays host to a vast array of bacteria, found in oral cavities, skin, gastrointestinal tract and the vagina. some bacteria are harmful while others are beneficial to the host. despite the availability of many methods to identify bacteria, most of them are only applicable to specific and cultivable bacteria and are also tedious. based on high throughput sequencing technology, this work derives 16s rrna sequences of bacteria and analyzes probiotics and pathogens species.201424418497
survey of infectious etiologies of bovine abortion during mid- to late gestation in dairy herds.bovine abortion of unknown infectious etiology still remains a major economic problem. thus, we investigated whether brucella spp., listeria monocytogenes, salmonella spp., campylobacter spp. and coxiella burnetii are associated with abortion and/or stillbirth in tunisian dairy cattle. using a pan-chlamydiales pcr, we also investigated the role of chlamydiaceae, waddlia chondrophila, parachlamydia acanthamoebae and other members of the chlamydiales order in this setting. veterinary samples taken ...201424662769
metaphylogenomic and potential functionality of the limpet patella pellucida's gastrointestinal tract microbiome.this study investigated the microbial diversity associated with the digestive tract of the seaweed grazing marine limpet patella pellucida. using a modified indirect dna extraction protocol and performing metagenomic profiling based on specific prokaryotic marker genes, the abundance of bacterial groups was identified from the analyzed metagenome. the members of three significantly abundant phyla of proteobacteria, firmicutes and bacteroidetes were characterized through the literature and their ...201425334059
the wild side of disease control at the wildlife-livestock-human interface: a review.the control of diseases shared with wildlife requires the development of strategies that will reduce pathogen transmission between wildlife and both domestic animals and human beings. this review describes and criticizes the options currently applied and attempts to forecast wildlife disease control in the coming decades. establishing a proper surveillance and monitoring scheme (disease and population wise) is the absolute priority before even making the decision as to whether or not to interven ...201426664926
the wild side of disease control at the wildlife-livestock-human interface: a review.the control of diseases shared with wildlife requires the development of strategies that will reduce pathogen transmission between wildlife and both domestic animals and human beings. this review describes and criticizes the options currently applied and attempts to forecast wildlife disease control in the coming decades. establishing a proper surveillance and monitoring scheme (disease and population wise) is the absolute priority before even making the decision as to whether or not to interven ...201426664926
mechanisms of antimicrobial peptide resistance in gram-negative bacteria.cationic antimicrobial peptides (camps) are important innate immune defenses that inhibit colonization by pathogens and contribute to clearance of infections. gram-negative bacterial pathogens are a major target, yet many of them have evolved mechanisms to resist these antimicrobials. these resistance mechanisms can be critical contributors to bacterial virulence and are often crucial for survival within the host. here, we summarize methods used by gram-negative bacteria to resist camps. underst ...201425927010
mechanisms of antimicrobial peptide resistance in gram-negative bacteria.cationic antimicrobial peptides (camps) are important innate immune defenses that inhibit colonization by pathogens and contribute to clearance of infections. gram-negative bacterial pathogens are a major target, yet many of them have evolved mechanisms to resist these antimicrobials. these resistance mechanisms can be critical contributors to bacterial virulence and are often crucial for survival within the host. here, we summarize methods used by gram-negative bacteria to resist camps. underst ...201425927010
the construction and evaluation of reference spectra for the identification of human pathogenic microorganisms by maldi-tof ms.matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (maldi-tof ms) is an emerging technique for the rapid and high-throughput identification of microorganisms. there remains a dearth of studies in which a large number of pathogenic microorganisms from a particular country or region are utilized for systematic analyses. in this study, peptide mass reference spectra (pmrs) were constructed and evaluated from numerous human pathogens (a total of 1019 strains from 94 species ...201425181391
evolutionary perspectives on wildlife disease: concepts and applications.wildlife disease has the potential to cause significant ecological, socioeconomic, and health impacts. as a result, all tools available need to be employed when host-pathogen dynamics merit conservation or management interventions. evolutionary principles, such as evolutionary history, phenotypic and genetic variation, and selection, have the potential to unravel many of the complex ecological realities of infectious disease in the wild. despite this, their application to wildlife disease ecolog ...201425469154
a quantitative prioritisation of human and domestic animal pathogens in europe.disease or pathogen risk prioritisations aid understanding of infectious agent impact within surveillance or mitigation and biosecurity work, but take significant development. previous work has shown the h-(hirsch-)index as an alternative proxy. we present a weighted risk analysis describing infectious pathogen impact for human health (human pathogens) and well-being (domestic animal pathogens) using an objective, evidence-based, repeatable approach; the h-index. this study established the highe ...201425136810
targeting tlr2 for vaccine development.novel and more effective immunization strategies against many animal diseases may profit from the current knowledge on the modulation of specific immunity through stimulation of innate immune receptors. toll-like receptor (tlr)2-targeting formulations, such as synthetic lipopeptides and antigens expressed in fusion with lipoproteins, have been shown to have built-in adjuvant properties and to be effective at inducing cellular and humoral immune mechanisms in different animal species. however, co ...201425057505
legionella dumoffii utilizes exogenous choline for phosphatidylcholine synthesis.phosphatidycholine (pc) is the major membrane-forming phospholipid in eukaryotes but it has been found in only a limited number of prokaryotes. bacteria synthesize pc via the phospholipid n-methylation pathway (pmt) or via the phosphatidylcholine synthase pathway (pcs) or both. here, we demonstrated that legionella dumoffii has the ability to utilize exogenous choline for phosphatidylcholine (pc) synthesis when bacteria grow in the presence of choline. the pcs seems to be a primary pathway for s ...201424821544
prevalence of bacterial contamination when using a diversion pouch during blood collection: a single center study in malaysia.the implementation of diversion pouches is to minimise the risk of bacterial contamination as the initial blood flow is prevented from entering primary bag collections as it is diverted into a pouch. this study was carried out to determine the prevalence of bacterial contamination in the diversion pouches used during blood collections in the transfusion department of hospital seberang jaya, penang, malaysia.201425246835
benchmarking of methods for genomic taxonomy.one of the first issues that emerges when a prokaryotic organism of interest is encountered is the question of what it is--that is, which species it is. the 16s rrna gene formed the basis of the first method for sequence-based taxonomy and has had a tremendous impact on the field of microbiology. nevertheless, the method has been found to have a number of shortcomings. in the current study, we trained and benchmarked five methods for whole-genome sequence-based prokaryotic species identification ...201424574292
membrane lipids in agrobacterium tumefaciens: biosynthetic pathways and importance for pathogenesis.many cellular processes critically depend on the membrane composition. in this review, we focus on the biosynthesis and physiological roles of membrane lipids in the plant pathogen agrobacterium tumefaciens. the major components of a. tumefaciens membranes are the phospholipids (pls), phosphatidylethanolamine (pe), phosphatidylglycerol, phosphatidylcholine (pc) and cardiolipin, and ornithine lipids (ols). under phosphate-limited conditions, the membrane composition shifts to phosphate-free lipid ...201424723930
transition metal ions at the crossroads of mucosal immunity and microbial pathogenesis.transition metal ions are essential micronutrients for all living organisms. in mammals, these ions are often protein-bound and sequestered within cells, limiting their availability to microbes. moreover, in response to infection, mammalian hosts further reduce the availability of metal nutrients by activating epithelial cells and recruiting neutrophils, both of which release metal-binding proteins with antimicrobial function. microorganisms, in turn, have evolved sophisticated systems to overco ...201424478990
persisters, persistent infections and the yin-yang model.persisters are a small fraction of quiescent bacterial cells that survive lethal antibiotics or stresses but can regrow under appropriate conditions. persisters underlie persistent and latent infections and post-treatment relapse, posing significant challenges for the treatment of many bacterial infections. the current definition of persisters has drawbacks, and a yin-yang model is proposed to describe the heterogeneous nature of persisters that have to be defined in highly specific conditions. ...201426038493
humans and cattle: a review of bovine zoonoses.infectious disease prevention and control has been among the top public health objectives during the last century. however, controlling disease due to pathogens that move between animals and humans has been challenging. such zoonotic pathogens have been responsible for the majority of new human disease threats and a number of recent international epidemics. currently, our surveillance systems often lack the ability to monitor the human-animal interface for emergent pathogens. identifying and ult ...201424341911
impact of crispr immunity on the emergence and virulence of bacterial pathogens.crispr-cas systems protect prokaryotes from viruses and plasmids and function primarily as an adaptive immune system in these organisms. recent discoveries, however, revealed unexpected roles for crispr loci as barriers to horizontal gene transfer and as modulators of gene expression. we review how both of these functions of crispr-cas systems can affect the emergence and virulence of human bacterial pathogens.201324581697
impact of crispr immunity on the emergence and virulence of bacterial pathogens.crispr-cas systems protect prokaryotes from viruses and plasmids and function primarily as an adaptive immune system in these organisms. recent discoveries, however, revealed unexpected roles for crispr loci as barriers to horizontal gene transfer and as modulators of gene expression. we review how both of these functions of crispr-cas systems can affect the emergence and virulence of human bacterial pathogens.201324581697
detection of brucella abortus dna and rna in different stages of development of the sucking louse haematopinus tuberculatus.brucellosis is considered the world's most widespread zoonotic infection. it causes abortion and sterility in livestock leading to serious economic losses and has even more serious medical impact in humans, since it can be a trigger to more than 500,000 infections per year worldwide. the aim of this study was to evaluate the role of haematopinus tuberculatus, a louse that can parasitize several ruminants, as a new host of brucellosis. louse specimens were collected from seropositive and seronega ...201324289112
immunoproteomic analysis of proteins expressed by two related pathogens, burkholderia multivorans and burkholderia cenocepacia, during human infection.burkholderia cepacia complex (bcc) is an opportunistic bacterial pathogen that causes chronic infections in people with cystic fibrosis (cf). it is a highly antibiotic resistant organism and bcc infections are rarely cleared from patients, once they are colonized. the two most clinically relevant species within bcc are burkholderia cenocepacia and burkholderia multivorans. the virulence of these pathogens has not been fully elucidated and the virulence proteins expressed during human infection h ...201324260482
non-viable borrelia burgdorferi induce inflammatory mediators and apoptosis in human oligodendrocytes.in previous studies, exposure to live borrelia burgdorferi was shown to induce inflammation and apoptosis of human oligodendrocytes. in this study we assessed the ability of non-viable bacteria (heat killed or sonicated) to induce inflammatory mediators and cell death. both heat-killed and sonicated bacteria induced release of ccl2, il-6, and cxcl8 from oligodendrocytes in a dose dependent manner. in addition, non-viable b. burgdorferi also induced cell death as evaluated by terminal deoxynucleo ...201324157855
manganese complexes: diverse metabolic routes to oxidative stress resistance in prokaryotes and yeast.antioxidant enzymes are thought to provide critical protection to cells against reactive oxygen species (ros). however, many organisms can fully compensate for the loss of such enzymatic defenses by accumulating metabolites and mn²⁺, which can form catalytic mn-antioxidants. accumulated metabolites can direct reactivity of mn²⁺ with superoxide and specifically shield proteins from oxidative damage.201323249283
diagnostic ophthalmology. anterior uveitis of the right eye. 201324155500
discovery of catalases in members of the chlamydiales order.catalase is an important virulence factor for survival in macrophages and other phagocytic cells. in chlamydiaceae, no catalase had been described so far. with the sequencing and annotation of the full genomes of chlamydia-related bacteria, the presence of different catalase-encoding genes has been documented. however, their distribution in the chlamydiales order and the functionality of these catalases remain unknown. phylogeny of chlamydial catalases was inferred using mrbayes, maximum likelih ...201323729651
toll-like receptor 6 plays an important role in host innate resistance to brucella abortus infection in mice.brucella abortus is recognized by several toll-like receptor (tlr)-associated pathways triggering proinflammatory responses that affect both the nature and intensity of the immune response. previously, we demonstrated that b. abortus-mediated dendritic cell (dc) maturation and control of infection are dependent on the adaptor molecule myd88. however, the involvement of all tlrs in response to b. abortus infection is not completely understood. therefore, we decided to evaluate the requirement for ...201323460520
abstracts of the 36th annual meeting of the society of general internal medicine. april 24-27, 2013. denver, colorado, usa. 201323625304
the htra protease of borrelia burgdorferi degrades outer membrane protein bmpd and chemotaxis phosphatase chex.borrelia burgdorferi, the spirochaetal agent of lyme disease, codes for a single htra protein, htrabb (bb0104) that is homologous to degp of escherichia coli (41% amino acid identity). htrabb shows physical and biochemical similarities to degp in that it has the trimer as its fundamental unit and can degrade casein via its catalytic serine. recombinant htrabb exhibits proteolytic activity in vitro, while a mutant (htrabbs198a) does not. however, htrabb and degp have some important differences as ...201323565798
zoonoses in humans from small rural properties in jataizinho, parana, brazil.the aim of this study was to conduct a serological survey for lyme diseases, brucellosis, leptospirosis and toxoplasmosis and identify the risk variables related to these zoonoses in humans living in the rural area of jataizinho, state of parana, brazil. a total of 63 rural properties were surveyed. additionally, 207 serum samples collected from these rural area inhabitants were tested for indirect immunofluorescence (ifi) and western blots (wb) were performed to detect borrelia burgdorferi (sen ...201324159294
biochemical and mutational analysis of a novel nicotinamidase from oceanobacillus iheyensis hte831.nicotinamidases catalyze the hydrolysis of nicotinamide to nicotinic acid and ammonia, an important reaction in the nad(+) salvage pathway. this paper reports a new nicotinamidase from the deep-sea extremely halotolerant and alkaliphilic oceanobacillus iheyensis hte831 (oinic). the enzyme was active towards nicotinamide and several analogues, including the prodrug pyrazinamide. the enzyme was more nicotinamidase (kcat/km  = 43.5 mm(-1)s(-1)) than pyrazinamidase (kcat/km  = 3.2 mm(-1)s(-1)). muta ...201323451075
architecture and host interface of environmental chlamydiae revealed by electron cryotomography.chlamydiae comprise important pathogenic and symbiotic bacteria that alternate between morphologically and physiologically different life stages during their developmental cycle. using electron cryotomography, we characterize the ultrastructure of the developmental stages of three environmental chlamydiae: parachlamydia acanthamoebae, protochlamydia amoebophila and simkania negevensis. we show that chemical fixation and dehydration alter the cell shape of parachlamydia and that the crescent body ...201324118768
architecture and host interface of environmental chlamydiae revealed by electron cryotomography.chlamydiae comprise important pathogenic and symbiotic bacteria that alternate between morphologically and physiologically different life stages during their developmental cycle. using electron cryotomography, we characterize the ultrastructure of the developmental stages of three environmental chlamydiae: parachlamydia acanthamoebae, protochlamydia amoebophila and simkania negevensis. we show that chemical fixation and dehydration alter the cell shape of parachlamydia and that the crescent body ...201324118768
identification of a protective protein from stationary phase exoproteome of brucella abortus.brucellosis is a worldwide zoonotic disease. no brucella vaccine is available for use in humans and existing animal vaccines have limitations. in order to search the putative vaccine candidates, we studied the exoproteome of b. abortus nctc 10093 using 2de-ms approach. twenty six proteins were identified using maldi-tof-tof tandem mass spectrometry. outer membrane protein 25, d galactose periplasmic binding protein, oligopeptide abc transporter protein and isopropylmalate synthase were found to ...201323913725
from mice to women: the conundrum of immunity to infection during pregnancy.resistance to infection is the ability of the host to evoke a strong immune response sufficient to eliminate the infectious agent. in contrast, maternal tolerance to the fetus necessitates careful regulation of immune responses. successful pregnancy requires the maternal host to effectively balance the opposing processes of maternal immune reactivity and tolerance to the fetus. however, this balance can be perturbed by infections which are recognized as the major cause of adverse pregnancy outco ...201323432873
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