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quantification of bacterial indicators and zoonotic pathogens in dairy wastewater ponds.zoonotic pathogens in land-applied dairy wastewaters are a potential health risk. the occurrence and abundance of 10 pathogens and 3 fecal indicators were determined by quantitative real-time pcr (qpcr) in samples from 30 dairy wastewaters from southern idaho. samples tested positive for campylobacter jejuni, stx(1)- and eaea-positive escherichia coli, listeria monocytogenes, mycobacterium avium subsp. paratuberculosis, and salmonella enterica, with mean recoveries of genomic dna corresponding t ...201222983964
health assessment and seroepidemiologic survey of potential pathogens in wild antillean manatees (trichechus manatus manatus).the antillean manatee (trichechus manatus manatus), a subspecies of the west indian manatee, inhabits fresh, brackish, and warm coastal waters distributed along the eastern border of central america, the northern coast of south america, and throughout the wider caribbean region. threatened primarily by human encroachment, poaching, and habitat degradation, antillean manatees are listed as endangered by the international union for the conservation of nature. the impact of disease on population vi ...201222984521
the ompa family of proteins: roles in bacterial pathogenesis and immunity.the ompa family of outer membrane proteins is a group of genetically related, heat-modifiable, surface-exposed, porin proteins that are in high-copy number in the outer membrane of mainly gram-negative bacteria. ompa proteins are characterized by an n-terminal domain that forms an eight-stranded, anti-parallel β barrel, which is embedded in the outer membrane. the c-terminal domain is globular and located in the periplasmic space. escherichia coli ompa is the best characterized of the proteins. ...201322986056
detection of severe fever with thrombocytopenia syndrome virus by reverse transcription-cross-priming amplification coupled with vertical flow visualization.a virus known as severe fever with thrombocytopenia syndrome virus (sftsv) was recently identified as the etiological agent of severe fever with thrombocytopenia syndrome (sfts) in china. reliable laboratory detection and identification of this virus are likely to become clinically and epidemiologically desirable. we developed a nearly instrument-free, simple molecular method which incorporates reverse transcription-cross-priming amplification (rt-cpa) coupled with a vertical flow (vf) visualiza ...201222993179
[application of multiple-locus variable number tandem repeat analysis (mlva) on molecular typing of leptospira interrogans]. 201022997605
chemotactic behavior of pathogenic and nonpathogenic leptospira species.we have developed a capillary tube assay in combination with real-time pcr to quantitate the number of chemoattracted leptospira cells. we identified tween 80, glucose, sucrose, and pyruvate as attractants for leptospira cells; amino acids and vitamin b(12) were found to be nonchemotactic or weakly chemotactic. this assay has the general applicability to further our understanding of leptospiral chemotaxis.201223001652
a serological survey of leptospiral antibodies in dogs in new zealand.to investigate the prevalence of titres to four endemic leptospiral serovars in dog sera from the lower half of the north island, and the south island of new zealand submitted to diagnostic laboratories, and to explore the association between the prevalence of seropositive samples to leptospirosis and breed group, age group and sex.201323013160
the aspergillus fumigatus dihydroxyacid dehydratase ilv3a/ilvc is required for full virulence.dihydroxyacid dehydratase (dhad) is a key enzyme in the branched-chain amino acid biosynthetic pathway that exists in a variety of organisms, including fungi, plants and bacteria, but not humans. in this study we identified four putative dhad genes from the filamentous fungus aspergillus fumigatus by homology to saccharomyces cerevisiae ilv3. two of these genes, afua_2g14210 and afua_1g03550, initially designated afilv3a and afilv3b for this study, clustered in the same group as s. cerevisiae il ...201223028460
leptospira interrogans shotgun phage display identified ligb as a heparin-binding protein.ligb is an adhesin from pathogenic leptospira that is able to bind to extracellular matrix and is considered a virulence factor. a shotgun phage display genomic library was constructed and used for panning against heparan sulfate proteoglycan (hspg). a phage clone encoding part of ligb protein was selected in panning experiments and showed specific binding to heparin. to validate the selected clone, fragments of ligb were produced as recombinant proteins and showed affinity to heparin and to mam ...201223044419
molecular characterization by lssp-pcr and dna sequencing of a pathogenic isolate of leptospira interrogans from brazil.we report the initial characterization of a leptospiral isolate, leptospira interrogans, serogroup sejroe, serovar hardjo, genotype hardjoprajitno, strain norma, and its relatedness with l. interrogans, serogroup sejroe, serovar hardjo, genotype hardjoprajitno, strain hardjo and leptospira borgpetersenii, serogroup sejroe, serovar hardjo, genotype hardjobovis, strain sponselee. the norma strain singled out during a leptospirosis outbreak in cattle immunized with antigens from the reference strai ...201223057087
characterization of nitric oxide-inducing lipid a derived from mesorhizobium loti lipopolysaccharide.mesorhizobium loti is a member of the rhizobia and forms nitrogen-fixing symbioses with several lotus species. recently, it was reported that m. loti bacterial cells and their lipopolysaccharide (lps) preparations transiently induced nitric oxide (no) production in the roots of l. japonicus. we subsequently found that polysaccharides and the lipid a moiety were responsible for this no induction. in this study, we elucidated the chemical structure of m. loti lipid a and characterized its no-induc ...201223059724
exposure to selected pathogens in to selected pathogens in geoffroy's cats and domestic carnivores from central argentina.wild carnivores share a high percentage of parasites and viruses with closely related domestic carnivores. because of increased overlap and potential contact with domestic species, we conducted a retrospective serosurvey for 11 common carnivore pathogens in 40 geoffroy's cats (leopardus geoffroyi) sampled between 2000 and 2008 within or near two protected areas in central argentina (lihué calel national park, la pampa, and campos del tuyú national park, buenos aires), as well as five domestic ca ...201223060491
humanized tlr4/md-2 mice reveal lps recognition differentially impacts susceptibility to yersinia pestis and salmonella enterica.although lipopolysaccharide (lps) stimulation through the toll-like receptor (tlr)-4/md-2 receptor complex activates host defense against gram-negative bacterial pathogens, how species-specific differences in lps recognition impact host defense remains undefined. herein, we establish how temperature dependent shifts in the lipid a of yersinia pestis lps that differentially impact recognition by mouse versus human tlr4/md-2 dictate infection susceptibility. when grown at 37°c, y. pestis lps is hy ...201223071439
evolutionary analyses of non-genealogical bonds produced by introgressive descent.all evolutionary biologists are familiar with evolutionary units that evolve by vertical descent in a tree-like fashion in single lineages. however, many other kinds of processes contribute to evolutionary diversity. in vertical descent, the genetic material of a particular evolutionary unit is propagated by replication inside its own lineage. in what we call introgressive descent, the genetic material of a particular evolutionary unit propagates into different host structures and is replicated ...201223090996
characterization of lic11207, a novel leptospiral protein that is recognized by human convalescent sera and prevents apoptosis of polymorphonuclear leukocytes.we report the study of a predicted outer-membrane leptospiral protein encoded by the gene lic11207. this protein is conserved in several pathogenic leptospiral strains but is absent in the saprophyte leptospira biflexa. this putative outer-membrane protein has a domain of unknown function (duf) 1565 found in several phylogenetically diverse bacteria and in the archaeon methanosarcina acetivorans. the gene was cloned and expressed in escherichia coli bl21 (si) strain using the expression vector p ...201323092690
in vivo cell aggregations of a recent swine biofilm-forming isolate of leptospira interrogans strain from argentina.leptospirosis is a zoonosis of ubiquitous distribution caused by spirochetes. leptospires exist either as saprophytic water-associated organisms or as animal pathogens that can survive in water. previous works have demonstrated that both saprophytic and pathogenic leptospires are able to produce functional biofilms, which consist of a community of bacteria embedded in an extracellular matrix attached to a surface. this structure is believed to provide protection from environmental aggressiveness ...201223102459
a survey of rodent-borne pathogens carried by wild rattus spp. in northern vietnam.to examine the prevalence of human pathogens carried by rats in urban areas in hanoi and hai phong, vietnam, we live-trapped 100 rats in january 2011 and screened them for a panel of bacteria and viruses. antibodies against leptospira interrogans (22·0%), seoul virus (14·0%) and rat hepatitis e virus (23·0%) were detected in rats, but antibodies against yersinia pestis were not detected. antibodies against l. interrogans and seoul virus were found only in adult rats. in contrast, antibodies to r ...201323114204
rapid isolation and susceptibility testing of leptospira spp. using a new solid medium, lvw agar.pathogenic leptospira spp., the causative agents of leptospirosis, are slow-growing gram-negative spirochetes. isolation of leptospira from clinical samples and testing of antimicrobial susceptibility are difficult and time-consuming. here, we describe the development of a new solid medium that facilitates more-rapid growth of leptospira spp. and the use of this medium to evaluate the etest's performance in determining antimicrobial mics to drugs in common use for leptospirosis. the medium was d ...201323114772
temporal trends in bulk milk antibodies to salmonella, neospora caninum, and leptospira interrogans serovar hardjo in irish dairy herds.bulk milk samples were collected from 309 irish dairy herds at four time points during 2009 and tested for antibodies to salmonella spp., n. caninum, and l. hardjo, three abortifacient agents in irish dairy herds. of the 312 study herds, 49% vaccinated against salmonella and 76% vaccinated against l. hardjo. in unvaccinated herds, the overall prevalence of antibody positive herds was 49% for salmonella, 19% for n. caninum and 86% for l. hardjo. there was no association between both testing posit ...201323117041
bacterial plasminogen receptors: mediators of a multifaceted relationship.multiple species of bacteria are able to sequester the host zymogen plasminogen to the cell surface. once localised to the bacterial surface, plasminogen can act as a cofactor in adhesion, or, following activation to plasmin, provide a source of potent proteolytic activity. numerous bacterial plasminogen receptors have been identified, and the mechanisms by which they interact with plasminogen are diverse. here we provide an overview of bacterial plasminogen receptors and discuss the diverse rol ...201223118502
plasminogen binding proteins and plasmin generation on the surface of leptospira spp.: the contribution to the bacteria-host interactions.leptospirosis is considered a neglected infectious disease of human and veterinary concern. although extensive investigations on host-pathogen interactions have been pursued by several research groups, mechanisms of infection, invasion and persistence of pathogenic leptospira spp. remain to be elucidated. we have reported the ability of leptospires to bind human plasminogen (plg) and to generate enzimatically active plasmin (pla) on the bacteria surface. pla-coated leptospira can degrade immobil ...201223118516
molecular typing of leptospira interrogans strains isolated from rattus tanezumi in guizhou province, southwest of china.to identify and type three leptospires isolated from rattus tanezumi in guizhou province by using three molecular techniques (pfge, mlva, and mlst), reveal the molecular characteristic of causative agents of local leptospirosis and evaluate these three molecular methods based on their detection resolution and efficiency.201223122311
leptospira and inflammation.leptospirosis is an important zoonosis and has a worldwide impact on public health. this paper will discuss both the role of immunogenic and pathogenic molecules during leptospirosis infection and possible new targets for immunotherapy against leptospira components. leptospira, possess a wide variety of mechanisms that allow them to evade the host immune system and cause infection. many molecules contribute to the ability of leptospira to adhere, invade, and colonize. the recent sequencing of th ...201223132959
accuracy of a dual path platform (dpp) assay for the rapid point-of-care diagnosis of human leptospirosis.diagnosis of leptospirosis by the gold standard serologic assay, the microscopic agglutination test (mat), requires paired sera and is not widely available. we developed a rapid assay using immunodominant leptospira immunoglobulin-like (lig) proteins in a dual path platform (dpp). this study aimed to evaluate the assay's diagnostic performance in the setting of urban transmission.201223133686
assessment of real-time pcr assay for detection of rickettsia spp. and rickettsia rickettsii in banked clinical samples.two novel real-time pcr assays were developed for the detection of rickettsia spp. one assay detects all tested rickettsia spp.; the other is specific for rickettsia rickettsii. evaluation using dna from human blood and tissue samples showed both assays to be more sensitive than nested pcr assays currently in use at the cdc.201323135935
comparative analysis of leptospira strains isolated from environmental soil and water in the philippines and japan.there have been few reports on the epidemiological analysis of environmental leptospira isolates. this is probably because the isolation of leptospires from the environment was usually unsuccessful due to the overgrowth of contaminants and the slow growth of leptospira. in this study, we collected a total of 88 samples of soil and water from three sites: metro manila and nueva ecija, philippines (an area where leptospira is now endemic), and fukuoka, japan (an area where leptospira was once ende ...201323144130
cross-sectional study of leptospira seroprevalence in humans, rats, mice, and dogs in a main tropical sea-port city.samples were collected from 128 symptomatic humans, 83 dogs, 49 mice, and 20 rats (rattus rattus: 16; rattus norvegicus: 4) in neighborhoods where human leptospirosis have been reported within the principal sea-port city of colombia. seroprevalences were assessed against 19 pathogenic, 1 intermediate pathogenic, and 1 saprophytic leptospira serogroups. pathogenic leptospira were confirmed using conventional leptospira-specific polymerase chain-reaction and pulsed-field gel electrophoresis analys ...201323149584
unexpected diversity of signal peptides in prokaryotes.signal peptides are a cornerstone mechanism for cellular protein localization, yet until now experimental determination of signal peptides has come from only a narrow taxonomic sampling. as a result, the dominant view is that sec-cleaved signal peptides in prokaryotes are defined by a canonical axa motif. although other residues are permitted in the motif, alanine is by far the most common. here we broadly examine proteomics data to reveal the signal peptide sequences for 32 bacterial and archae ...201223169999
evaluation of immunoprotective activity of six leptospiral proteins in the hamster model of leptospirosis.leptospirosis is a worldwide zoonosis caused by pathogenic leptospira. the whole-genome sequence of l. interrogans serovar copenhageni together with bioinformatics tools represent a great opportunity to search for novel antigen candidates that could be used as subunit vaccine against leptospirosis. we focused on six genes encoding for conserved hypothetical proteins predicted to be exported to the outer membrane. the genes were amplified by pcr from leptospira interrogans genomic dna and were cl ...201223173023
a novel tetravalent leptospira bacterin protects against infection and shedding following challenge in dogs.recent evidence based on the current epidemiological situation suggests that vaccines against canine leptospirosis in europe should be directed against infection with leptospira interrogans (sensu lato) serogroups canicola, icterohaemorrhagiae, grippotyphosa and australis. in the eight studies presented here, dogs were vaccinated with nobivac l4 (msd animal health), a new tetravalent inactivated vaccine containing antigen from four strains representing these four serogroups. the dogs were then c ...201223180149
a novel tetravalent leptospira bacterin protects against infection and shedding following challenge in dogs.recent evidence based on the current epidemiological situation suggests that vaccines against canine leptospirosis in europe should be directed against infection with leptospira interrogans (sensu lato) serogroups canicola, icterohaemorrhagiae, grippotyphosa and australis. in the eight studies presented here, dogs were vaccinated with nobivac l4 (msd animal health), a new tetravalent inactivated vaccine containing antigen from four strains representing these four serogroups. the dogs were then c ...201223180149
structure determination of lpxa from the lipopolysaccharide-synthesis pathway of acinetobacter baumannii.acinetobacter baumannii is a gram-negative pathogenic bacterium which is resistant to most currently available antibiotics and that poses a significant health threat to hospital patients. lpxa is a key enzyme in the biosynthetic pathway of the lipopolysaccharides that are components of the bacterial outer membrane. it is a potential target for antibacterial agents that might be used to fight a. baumannii infections. this paper describes the structure determination of the apo form of lpxa in spac ...201223192027
cluster of leptospirosis cases among military personnel in rio de janeiro, brazil.we report two cases of leptospirosis in military personnel in southeastern brazil. the cases were hospitalized following field training exercises, and presented with acute meningoencephalitis, respiratory illnesses, and skin rash. leptospira interrogans serovars icterohaemorrhagiae, hebdomadis, patoc, and cynopteri were identified in the cases by microscopic agglutination test and pcr.201323195639
identification of epitopes in leptospira borgpetersenii leucine-rich repeat proteins.leptospirosis is considered to be a re-emerging disease that has impacts on public health both globally and in and thailand. the leptospires outbreak in thailand during 1999 was largely due to the etiologic agent leptospira borgpetersenii serogroup sejroe. this had a related immunity profile in cows from thailand, which serovars tarassovi and sejroe were prevalent. development of a vaccine protecting against leptospiral infection in livestock has been considered. one family of proteins being tar ...201323201041
leptospirosis outbreaks in nicaragua: identifying critical areas and exploring drivers for evidence-based planning.leptospirosis is an epidemic-prone zoonotic disease that occurs worldwide. in central america, leptospirosis outbreaks have been reported in almost all countries; nicaragua in particular has faced several outbreaks. the objective of this study was to stratify the risk and identify "critical areas" for leptospirosis outbreaks in nicaragua, and to perform an exploratory analysis of potential "drivers". this ecological study includes the entire country (153 municipalities). cases from 2004 to 2010 ...201223202822
serosurveillance for livestock pathogens in free-ranging mule deer (odocoileus hemionus).routine disease surveillance has been conducted for decades in mule deer (odocoileus hemionus) in california for pathogens shared between wildlife and domestic ruminants that may have implications for the animal production industry and wildlife health. deer sampled from 1990 to 2007 (n = 2,619) were tested for exposure to six pathogens: bluetongue virus (btv), epizootic hemorrhagic disease virus (ehdv), bovine viral diarrhea virus (bvdv), leptospira spp., anaplasma spp. and brucella spp. we eval ...201223209790
molecular and serological investigation of leptospira and leptospirosis in dogs in japan.canine leptospirosis, which is caused by infection with pathogenic leptospira species, occurs worldwide, but information regarding the causative leptospira serotypes and genotypes and their effects on virulence in dogs remains limited. monitoring acute leptospirosis in dogs as sentinels can also aid in estimating the risk of human leptospirosis, particularly when the disease is rare, as it currently is in japan. among 283 clinically suspected cases of leptospirosis diagnosed from august 2007 to ...201223264455
comparative seroprevalence of leptospira interrogans in colombian mammals along a climatic gradient.leptospirosis is a widespread zoonotic disease with well-established impacts on human health in tropical and subtropical regions. although leptospira spp. are known to readily infect many wildlife species, the understanding of interspecies and climatic variability in patterns of infection in neotropical mammals is limited. to improve the understanding of this interplay, 85 mammals representing 17 species were sampled from four colombian zoos along a climatic gradient. prevalence of the 21 primar ...201223272343
effect of osmolarity and viscosity on the motility of pathogenic and saprophytic leptospira.the motility of bacteria is an important factor in their infectivity. in this study, the motility of leptospira, a member of the spirochete family that causes a zoonotic disease known as leptospirosis, was analyzed in different viscous or osmotic conditions. motility assays revealed that both pathogenic and saprophytic strains increase their swimming speeds with increasing viscosity. however, only pathogenic leptospira interrogans maintained vigorous motility near physiological osmotic condition ...201323278547
adhesin activity of leptospira interrogans lipoprotein identified by in vivo and in vitro shotgun phage display.leptospira interrogans causes leptospirosis, one of the most common zoonotic diseases in the world. this pathogenic spirochete is able to bind to extracellular matrix, to express virulent factors and to cause host death. until now, there is no effective human vaccine for the disease. shotgun phage display genomic libraries of l. interrogans were constructed and used for in vivo biopanning in hamsters and screened for ligands able to bind to llc-pk1 epithelial cells. in both panning procedures, c ...201323291183
immunoproteomics: the key to discovery of new vaccine antigens against bacterial respiratory infections.the increase in antibiotic resistance and the shortage of new antimicrobials to prevent difficult bacterial infections underlines the importance of prophylactic therapies to prevent infection by bacterial pathogens. vaccination has reduced the incidence of many serious diseases, including respiratory bacterial infections. however, there are many pathogens for which no vaccine is available and some vaccines are not effective among all age groups or among immunocompromised individuals. immunoprote ...201223305366
in vivo gene expression and immunoreactivity of leptospira collagenase.pulmonary hemorrhage is an increasing cause of death of leptospirosis patients. bacterial collagenase has been shown to be involved in lung hemorrhage induced by various infectious agents. according to leptospira whole genome study, cola, a gene suggested to code for bacterial collagenase has been identified. we investigated cola gene expression in lung tissues of leptospira infected hamsters. golden syrian hamsters were injected intraperitoneally with leptospira interrogans serovar pyrogenes. t ...201323305770
first isolation of leptospira interrogans from lycalopex griseus (south american gray fox) in argentina shows new mlva genotype.to identify carriers of leptospira spp. in argentina, wild animals were trapped in buenos aires province during three nights, capturing 12 didelphis albiventris (white-eared opossum), six chaetophractus villosus (big hairy armadillo), five lycalopex griseus (south american gray fox), and two conepatus chinga (molina's hog-nosed skunk). all were tested by microscopic agglutination test, and five (two gray foxes, two armadillos, and one skunk) were positive for leptospira interrogans serovars cani ...201323307384
lipl32 is a subsurface lipoprotein of leptospira interrogans: presentation of new data and reevaluation of previous studies.the agents of leptospirosis, a zoonosis with worldwide distribution, are pathogenic spirochetes belonging to the genus leptospira. the leptospiral life cycle involves transmission via fresh water and colonization of the renal tubules of their reservoir hosts. infection of accidental hosts, including humans, may result in life-threatening sequelae. bacterial outer membrane proteins (omps), particularly those with surface-exposed regions, play crucial roles in pathogen virulence mechanisms and ada ...201323323152
risk factors and predictors of severe leptospirosis in new caledonia.leptospirosis is a major public health concern in new caledonia (nc) and in other tropical countries. severe manifestations of the disease are estimated to occur in 5-15% of all human infections worldwide and factors associated with these forms are poorly understood. our objectives were to identify risk factors and predictors of severe forms of leptospirosis in adults.201323326614
solution structure of the big domain from streptococcus pneumoniae reveals a novel ca2+-binding module.streptococcus pneumoniae is a pathogen causing acute respiratory infection, otitis media and some other severe diseases in human. in this study, the solution structure of a bacterial immunoglobulin-like (big) domain from a putative s. pneumoniae surface protein sp0498 was determined by nmr spectroscopy. sp0498 big domain adopts an eight-β-strand barrel-like fold, which is different in some aspects from the two-sheet sandwich-like fold of the canonical ig-like domains. intriguingly, we identified ...201323326635
seroprevalence of leptospirosis in dogs in urban harare and selected rural communities in zimbabwe.a cross-sectional study was conducted to investigate seroprevalence of canine leptospirosis in urban harare and five selected rural communities in zimbabwe and to assess public awareness of the disease. sera from randomly selected dogs were tested for antibodies to the serovars canicola, grippotyphosa, icterohaemorrhagiae and pomona of leptospira interrogans using an enzyme-linked immunosorbent assay. clinical chemistry was performed on all seropositive and selected seronegative sera to screen f ...201223327324
the gain and loss of chromosomal integron systems in the treponema species.integron systems are now recognized as important agents of bacterial evolution and are prevalent in most environments. one of the human pathogens known to harbor chromosomal integrons, the treponema spirochetes are the only clade among spirochete species found to carry integrons. with the recent release of many new treponema genomes, we were able to study the distribution of chromosomal integrons in this genus.201323339550
pancreatitis and myocarditis followed by pulmonary hemorrhage, a rare presentation of leptospirosis- a case report and literature survey.leptospirosis is a potentially fatal disease which can cause multi-organ dysfunction. it can rarely present as acute pancreatitis. this is the first ever report of leptospirosis presenting with acute pancreatitis and myocarditis followed by diffuse pulmonary hemorrhages to the best of our knowledge.201323347428
isolation and molecular characterization of leptospira interrogans and leptospira borgpetersenii isolates from the urban rat populations of kuala lumpur, malaysia.rats are considered the principal maintenance hosts of leptospira. the objectives of this study were isolation and identification of leptospira serovars circulating among urban rat populations in kuala lumpur. three hundred urban rats (73% rattus rattus and 27% r. norvegicus) from three different sites were trapped. twenty cultures were positive for leptospira using dark-field microscopy. r. rattus was the dominant carrier (70%). polymerase chain reaction (pcr) confirmed that all isolates were p ...201323358635
pathogenic and saprophytic leptospira species in water and soils from selected urban sites in peninsular malaysia.leptospira species were studied in water and soils from selected urban sites in malaysia. a total of 151 water (n=121) and soil (n=30) samples were collected from 12 recreational lakes and wet markets. all samples were filtered and inoculated into semi-solid ellinghausen and mccullough modified by johnson and harris (emjh) media supplemented with additional 5-fluorouracil. the cultures were then incubated at 30°c and observed under a dark field microscope with intervals of 10 days. a pcr assay t ...201323363618
importance of uncharged polar residues and proline in the proximal two-thirds (pro107-ser128) of the highly conserved region of mouse ileal na+-dependent bile acid transporter, slc10a2, in transport activity and cellular expression.slc10a2-mediated reabsorption of bile acids at the distal end of the ileum is the first step in enterohepatic circulation. because bile acids act not only as detergents but also as signaling molecules in lipid metabolism and energy production, slc10a2 is important as the key transporter for understanding the in vivo kinetics of bile acids. slc10a family members and the homologous genes of various species share a highly conserved region corresponding to gly104-pro142 of slc10a2. the functional im ...201323374508
para-(benzoyl)-phenylalanine as a potential inhibitor against lpxc of leptospira spp.: homology modeling, docking, and molecular dynamics study.leptospira interrogans, a gram-negative bacterial pathogen is the main cause of human leptospirosis. lipid a is a highly immunoreactive endotoxic center of lipopolysaccharide (lps) that anchors lps into the outer membrane of leptospira. discovery of compounds inhibiting lipid-a biosynthetic pathway would be promising for dissolving the structural integrity of membrane leading to cell lysis and death of leptospira. lpxc, a unique enzyme of lipid-a biosynthetic pathway was identified as common dru ...201423383626
crystallographic study to determine the substrate specificity of an l-serine-acetylating enzyme found in the d-cycloserine biosynthetic pathway.dcse, one of the enzymes found in the d-cycloserine biosynthetic pathway, displays a high sequence homology to l-homoserine o-acetyltransferase (hat), but it prefers l-serine over l-homoserine as the substrate. to clarify the substrate specificity, in the present study we determined the crystal structure of dcse at a 1.81-å resolution, showing that the overall structure of dcse is similar to that of hat, whereas a turn region to form an oxyanion hole is obviously different between dcse and hat: ...201323396912
the origin of 8-amino-3,8-dideoxy-d-manno-octulosonic acid (kdo8n) in the lipopolysaccharide of shewanella oneidensis.lipopolysaccharide (lps; endotoxin) is an essential component of the outer monolayer of nearly all gram-negative bacteria. lps is composed of a hydrophobic anchor, known as lipid a, an inner core oligosaccharide, and a repeating o-antigen polysaccharide. in nearly all species, the first sugar bridging the hydrophobic lipid a and the polysaccharide domain is 3-deoxy-d-manno-octulosonic acid (kdo), and thus it is critically important for lps biosynthesis. modifications to lipid a have been shown t ...201323413030
asymptomatic and chronic carriage of leptospira interrogans serovar pomona in california sea lions (zalophus californianus).since 1970, periodic outbreaks of leptospirosis, caused by pathogenic spirochetes in the genus leptospira, have caused morbidity and mortality of california sea lions (zalophus californianus) along the pacific coast of north america. yearly seasonal epizootics of varying magnitude occur between the months of july and december, with major epizootics occurring every 3-5 years. genetic and serological data suggest that leptospira interrogans serovar pomona is the infecting serovar and is enzootic i ...201323419822
leptospira interrogans survey by pcr in wild rodents coming from different urban areas of palermo, italy.dna extracted from the kidneys of rodents captured in different urban areas of palermo, italy, had been analysed for the presence of pathogenic l. interrogans sensu latu dna. pcr analysis had shown that in rodents captured close to green areas and small river up to 40 % animals give positive pcr results. not many cases of human leptospirosis are reported in sicilian island in which hot season is usually dry. but considering climate change toward subtropical aspect in sicily, with hot humid summe ...201323427420
[preservation for vaccinal strains of leptospira at liquid nitrogen].leptospira interrogans strains of cuban vaccine vax-spiral are preserved in fletcher's semi-solid medium, which guarantees the preservation of the cell viability for a few months.201323431625
molecular characterization of virulent leptospira interrogans serogroup icterohaemorrhagiae isolated from cavia aperea.leptospirosis is a worldwide zoonotic infection caused by pathogenic leptospira. synanthropic rodents are recognized carriers of leptospires; however, the role of wild rodents in the epidemiology of the disease is still incipient. in this work, we describe leptospira strain isolated from cavia aperea (brazilian guinea pig). the isolated strain was characterized by partial rpob gene sequencing, variable-number tandem-repeats and histopathological analysis. the strain was identified as leptospira ...201323435256
protein analysis by shotgun/bottom-up proteomics. 201323438204
development of immunochromatography-based methods for detection of leptospiral lipopolysaccharide antigen in urine.leptospirosis is an infectious disease caused by the spirochete bacteria leptospira spp. and is commonly found throughout the world. diagnosis of leptospirosis performed by culture and microscopic agglutination tests is laborious and time-consuming. therefore, we aimed to develop a novel immunochromatography (icg)-based method for detecting leptospira antigen in the urine of patients and animals. we used the 1h6 monoclonal antibody (mab), which is specific to the lipopolysaccharide (lps) that is ...201323467776
interaction of leptospira interrogans with human proteolytic systems enhances dissemination through endothelial cells and protease levels.we have recently reported the ability of leptospira to capture plasminogen (plg) and generate plasmin (pla) bound on the microbial surface in the presence of exogenous activators. in this work, we examined the effects of leptospiral plg binding for active penetration through the endothelial cell barrier and activation. the results indicate that leptospires with plg association or pla activation have enhanced migration activity through human umbilical vein endothelial cell (huvec) monolayers comp ...201323478319
a conserved region of leptospiral immunoglobulin-like a and b proteins as a dna vaccine elicits a prophylactic immune response against leptospirosis.the leptospiral immunoglobulin-like (lig) proteins liga and ligb possess immunoglobulin-like domains with 90-amino-acid repeats and are adhesion molecules involved in pathogenicity. they are conserved in pathogenic leptospira spp. and thus are of interest for use as serodiagnostic antigens and in recombinant vaccine formulations. the n-terminal amino acid sequences of the liga and ligb proteins are identical, but the c-terminal sequences vary. in this study, we evaluated the protective potential ...201323486420
essential calcium-binding cluster of leptospira lipl32 protein for inflammatory responses through the toll-like receptor 2 pathway.leptospirosis is the most widespread zoonosis caused by the pathogenic leptospira worldwide. lipl32, a 32-kda lipoprotein, is the most abundant protein on the outer membrane of leptospira and has an atypical poly(asp) motif ((161)dddddgdd(168)). the x-ray crystallographic structure of lipl32 revealed that the calcium-binding cluster of lipl32 includes several essential residues asp(132), thr(133), asp(164), asp(165), and tyr(178). the goals of this study were to determine possible roles of the c ...201323486465
evolutionary history of the plant pathogenic bacterium xanthomonas axonopodis.deciphering mechanisms shaping bacterial diversity should help to build tools to predict the emergence of infectious diseases. xanthomonads are plant pathogenic bacteria found worldwide. xanthomonas axonopodis is a genetically heterogeneous species clustering, into six groups, strains that are collectively pathogenic on a large number of plants. however, each strain displays a narrow host range. we address the question of the nature of the evolutionary processes--geographical and ecological spec ...201323505513
a prime-boost strategy using the novel vaccine candidate, lema, protects hamsters against leptospirosis.toward developing an effective vaccine capable of conferring heterologous protection, the putative lipoprotein lema, which presents an m3 epitope similar to that of listeria, was evaluated as a vaccine candidate in the hamster model of leptospirosis. lema is conserved (>70% pairwise identity) among the pathogenic leptospira spp., indicating its potential in stimulating a cross-protective immune response. using different vaccination strategies, including prime-boost, dna vaccine, and a subunit pr ...201323515012
p53 signalling controls cell cycle arrest and caspase-independent apoptosis in macrophages infected with pathogenic leptospira species.pathogenic leptospira species, the causative agents of leptospirosis, have been shown to induce macrophage apoptosis through caspase-independent, mitochondrion-related apoptosis inducing factor (aif) and endonuclease g (endog), but the signalling pathway leading to aif/endog-based macrophage apoptosis remains unknown. here we show that infection of leptospira interrogans caused a rapid increase in reactive oxygen species (ros), dna damage, and intranuclear foci of 53bp1 and phosphorylation of h2 ...201323521874
toll-like receptors as therapeutic targets for autoimmune connective tissue diseases.autoimmune connective tissue diseases (actds) are a family of consistent systemic autoimmune inflammatory disorders, including systemic lupus erythematosus (sle), rheumatoid arthritis (ra), systemic sclerosis (ssc) and sjögren's syndrome (ss). il-1r-like receptors (tlrs) are located on various cellular membranes and sense exogenous and endogenous danger-associated molecular patterns (damps) and pathogen-associated molecular patterns (pamps), playing a critical role in innate immune responses. du ...201323531543
structure and activity of the flagellar rotor protein fliy: a member of the chec phosphatase family.fliy is a flagellar rotor protein of the chec phosphatase family.201323532838
a case of mixed infections in a patient presenting with acute febrile illness in the tropics.concurrent infections with more than one etiological agent can result in an illness with overlapping symptoms, resulting in a situation where the diagnosis and management of such a patient could be challenging. we report a case of vivax malaria in a patient who was also serologically positive for leptospirosis and dengue.201323533853
leptospirosis risk increases with changes in species composition of rat populations.rats are major reservoirs of leptospirosis and considered as a main threat to biodiversity. a recent introduction of rattus rattus to the island of futuna (western polynesia) provided the opportunity to test if a possible change in species composition of rat populations would increase the risk of leptospirosis to humans. we trapped rodents on wallis and futuna and assessed leptospira carriage in 357 rodents (rattus norvegicus, r. rattus, rattus exulans, and mus domesticus) from 2008 to 2012. whi ...201323535996
in vitro assessment of functional properties of lactic acid bacteria isolated from faecal microbiota of healthy dogs for potential use as probiotics.lactic acid bacteria were isolated and identified in the faeces of chinese crested and yorkshire terrier pups and their probiotic features were investigated in vitro. thirty seven isolates were identified as lactobacillus or enterococcus. out of these isolates, 31 were lactic acid bacteria (lab) and belonged to the species lactobacillus reuteri (16/37; 43.3%), lactobacillus animalis (7/37; 18.9%), lactobacillus acidophilus (3/37; 8.1%), lactobacillus sanfranciscensis (2/37; 5.4%), lactobacillus ...201323538205
a gene transfer agent and a dynamic repertoire of secretion systems hold the keys to the explosive radiation of the emerging pathogen bartonella.gene transfer agents (gtas) randomly transfer short fragments of a bacterial genome. a novel putative gta was recently discovered in the mouse-infecting bacterium bartonella grahamii. although gtas are widespread in phylogenetically diverse bacteria, their role in evolution is largely unknown. here, we present a comparative analysis of 16 bartonella genomes ranging from 1.4 to 2.6 mb in size, including six novel genomes from bartonella isolated from a cow, two moose, two dogs, and a kangaroo. a ...201323555299
multiple single-cell genomes provide insight into functions of uncultured deltaproteobacteria in the human oral cavity.despite a long history of investigation, many bacteria associated with the human oral cavity have yet to be cultured. studies that correlate the presence or abundance of uncultured species with oral health or disease highlight the importance of these community members. thus, we sequenced several single-cell genomic amplicons from desulfobulbus and desulfovibrio (class deltaproteobacteria) to better understand their function within the human oral community and their association with periodontitis ...201323555659
detection of reactive canines to leptospira in campeche city, mexico.leptospira reactivity in stray and household dogs in campeche as well as associated risk factors to the seropositivity in household dogs have been herein determined. the survey included 323 dogs, 142 of which were stray dogs and 181 household dogs. nine leptospira interrogans serovars were tested by the microagglutination test. reactivity was 21.3 % (69/323), 17.2 % corresponded to household dogs and 26.7 % to stray dogs. leptospira canicola (29 %), leptospira hardjo (22.58 %), and leptospira ic ...201323560786
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
detection of leptospiral antibodies by microscopic agglutination test in north-east of iran.to detect leptospiral antibodies by microscopic agglutination test (mat) in north-east of iran.201123569764
a survey of zoonotic diseases in trade cattle slaughtered at tanga city abattoir: a cause of public health concern.to estimate the prevalence of hydatidosis, cysticercosis, tuberculosis, leptospirosis, brucellosis and toxoplasmosis in slaughtered bovine stock (aged ±3 years) at tanga city abattoir, tanzania.201223569835
[expression changes of major outer membrane protein antigens in leptospira interrogans during infection and its mechanism].to determine expression changes of major outer membrane protein(omp) antigens of leptospira interrogans serogroup icterohaemorrhagiae serovar lai strain lai during infection of human macrophages and its mechanism.201323585001
[prokaryotic expression of leptospira interrogans groel gene and immunoprotection of its products in hamsters].to construct a prokaryotic expression system of groel gene of leptospira interrogans serogroup icterohaemorrhagia serovar lai strain lai, and to determine the immunoprotective effect of recombinant groel protein (rgroel) in lvg hamsters.201323585002
a ubiquitous method for street scale spatial data collection and analysis in challenging urban environments: mapping health risks using spatial video in haiti.fine-scale and longitudinal geospatial analysis of health risks in challenging urban areas is often limited by the lack of other spatial layers even if case data are available. underlying population counts, residential context, and associated causative factors such as standing water or trash locations are often missing unless collected through logistically difficult, and often expensive, surveys. the lack of spatial context also hinders the interpretation of results and designing intervention st ...201323587358
rats, cities, people, and pathogens: a systematic review and narrative synthesis of literature regarding the ecology of rat-associated zoonoses in urban centers.urban norway and black rats (rattus norvegicus and rattus rattus) are the source of a number of pathogens responsible for significant human morbidity and mortality in cities around the world. these pathogens include zoonotic bacteria (leptospira interrogans, yersina pestis, rickettsia typhi, bartonella spp., streptobacillus moniliformis), viruses (seoul hantavirus), and parasites (angiostrongylus cantonensis). a more complete understanding of the ecology of these pathogens in people and rats is ...201323590323
sex bias in infectious disease epidemiology: patterns and processes.infectious disease incidence is often male-biased. two main hypotheses have been proposed to explain this observation. the physiological hypothesis (ph) emphasizes differences in sex hormones and genetic architecture, while the behavioral hypothesis (bh) stresses gender-related differences in exposure. surprisingly, the population-level predictions of these hypotheses are yet to be thoroughly tested in humans.201323638062
climate variability and outbreaks of infectious diseases in europe.several studies provide evidence of a link between vector-borne disease outbreaks and el niño driven climate anomalies. less investigated are the effects of the north atlantic oscillation (nao). here, we test its impact on outbreak occurrences of 13 infectious diseases over europe during the last fifty years, controlling for potential bias due to increased surveillance and detection. nao variation statistically influenced the outbreak occurrence of eleven of the infectious diseases. seven diseas ...201323639950
a chimeric udp-glucose pyrophosphorylase produced by protein engineering exhibits sensitivity to allosteric regulators.in bacteria, glycogen or oligosaccharide accumulation involves glucose-1-phosphate partitioning into either adp-glucose (adp-glc) or udp-glc. their respective synthesis is catalyzed by allosterically regulated adp-glc pyrophosphorylase (ec 2.7.7.27, adp-glc ppase) or unregulated udp-glc ppase (ec 2.7.7.9). in this work, we characterized the udp-glc ppase from streptococcus mutans. in addition, we constructed a chimeric protein by cutting the c-terminal domain of the adp-glc ppase from escherichi ...201323648478
evaluation of the elastinolytic activity and protective effect of leptallo i, a protein composed by metalloprotease and fa5/8c domains, from leptospira interrogans copenhageni.leptospirosis is a re-emergent zoonosis, caused by pathogenic spirochetes from the genus lepstospira. to date, there is no protein described to be involved in leptospiral hemorrhagic manifestations, although several proteases have been reported for other bacterial infections. in this study we identified 12 putative metalloproteases from the genome of leptospira interrogans, and characterized for the first time a putative metalloprotease, here named leptallo i, as a potential zn(2+) dependent gly ...201323665291
aggregate-reactivation activity of the molecular chaperone clpb from ehrlichia chaffeensis.rickettsiale diseases, including human monocytic ehrlichiosis caused by ehrlichia chaffeensis, are the second leading cause of the tick-borne infections in the usa and a growing health concern. little is known about how e. chaffeensis survives the host-induced stress in vertebrate and tick hosts. a molecular chaperone clpb from several microorganisms has been reported to reactivate aggregated proteins in cooperation with the co-chaperones dnak/dnaj/grpe (kje). in this study, we performed the fir ...201323667479
leptospira interrogans at the human-wildlife interface in northern botswana: a newly identified public health threat.leptospirosis is the most widespread zoonosis in the world. in northern botswana, humans live in close proximity to a diversity of wildlife and peridomestic rodents and may be exposed to a variety of zoonotic pathogens. little is known regarding the occurrence and epidemiology of l. interrogans in africa despite the recognized global importance of this zoonotic disease and the threat it poses to public health. in botswana, banded mongooses (mungos mungo) live in close proximity to humans across ...201423672285
incidence of leptospirosis infection in the east zone of sao paulo city, brazil.leptospirosis is a zoonosis which is spread through contamined running water. this contaminations is seriously affected by the flooding which occurs in the area surrounding the aricanduva river. the transmission of the disease results mainly from the contact of water with soil contaminated by the urine of infected animals. we aimed to conduct an epidemiological survey on leptospirosis cases in sao paulo east zone area.201323672682
chemogenomics profiling of drug targets of peptidoglycan biosynthesis pathway in leptospira interrogans by virtual screening approaches.leptospirosis is a worldwide zoonosis of global concern caused by leptospira interrogans. the availability of ligand libraries has facilitated the search for novel drug targets using chemogenomics approaches, compared with the traditional method of drug discovery, which is time consuming and yields few leads with little intracellular information for guiding target selection. recent subtractive genomics studies have revealed the putative drug targets in peptidoglycan biosynthesis pathways in lept ...201323676922
detection of lipl32-specific igm by elisa in sera of patients with a clinical diagnosis of leptospirosis.successful treatment of leptospirosis is heavily dependent on early diagnosis and prompt initiation of antibiotic therapy. an elisa test to detect specific igm antibodies against lipl32 for early diagnosis of leptospirosis is described and evaluated here. one thousand one hundred and eighty sera from clinically suspected leptospirosis cases were enrolled together with 109 healthy volunteers selected from an endemic area between october 2007 and january 2010. patients were categorized based on th ...201323683367
the mtb proteome library: a resource of assays to quantify the complete proteome of mycobacterium tuberculosis.research advancing our understanding of mycobacterium tuberculosis (mtb) biology and complex host-mtb interactions requires consistent and precise quantitative measurements of mtb proteins. we describe the generation and validation of a compendium of assays to quantify 97% of the 4,012 annotated mtb proteins by the targeted mass spectrometric method selected reaction monitoring (srm). furthermore, we estimate the absolute abundance for 55% of all mtb proteins, revealing a dynamic range within th ...201323684311
leptospiral outer membrane protein lipl41 is not essential for acute leptospirosis but requires a small chaperone protein, lep, for stable expression.leptospirosis is a worldwide zoonosis caused by pathogenic leptospira spp., but knowledge of leptospiral pathogenesis remains limited. however, the development of mutagenesis systems has allowed the investigation of putative virulence factors and their involvement in leptospirosis. lipl41 is the third most abundant lipoprotein found in the outer membranes of pathogenic leptospires and has been considered a putative virulence factor. lipl41 is encoded on the large chromosome 28 bp upstream of a s ...201323690405
acyltransferases in bacteria.long-chain-length hydrophobic acyl residues play a vital role in a multitude of essential biological structures and processes. they build the inner hydrophobic layers of biological membranes, are converted to intracellular storage compounds, and are used to modify protein properties or function as membrane anchors, to name only a few functions. acyl thioesters are transferred by acyltransferases or transacylases to a variety of different substrates or are polymerized to lipophilic storage compou ...201323699259
precipitation of iron on the surface of leptospira interrogans is associated with mutation of the stress response metalloprotease htpx.high concentrations of free metal ions in the environment can be detrimental to bacterial survival. however, bacteria utilize strategies, including the activation of stress response pathways and immobilizing chemical elements on their surface, to limit this toxicity. in this study, we characterized la4131, the htpx-like m48 metalloprotease from leptospira interrogans, with a putative role in bacterial stress response and membrane homeostasis. growth of the la4131 transposon mutant strain (l522) ...201323709510
development of an enzyme-linked immunosorbent assay using a recombinant liga fragment comprising repeat domains 4 to 7.5 as an antigen for diagnosis of equine leptospirosis.leptospira immunoglobulin (ig)-like (lig) proteins are a novel family of surface-associated proteins in which the n-terminal 630 amino acids are conserved. in this study, we truncated the liga conserved region into 7 fragments comprising the 1st to 3rd (ligacon1-3), 4th to 7.5th (ligacon4-7.5), 4th (ligacon4), 4.5th to 5.5th (ligacon4.5-5.5), 5.5th to 6.5th (ligacon5.5-6.5), 4th to 5th (ligacon4-5), and 6th to 7.5th (ligacon6-7.5) repeat domains. all 7 recombinant lig proteins were screened usin ...201323720368
a review of pig pathology in tanzania.the approximately 1.58 million pigs in tanzania represent 3.7% of the national population of quadruped meat-producing animals. pigs are kept mainly by small producers who own 99.5% of the national stock in units that average 3.04 animals (range 2-48). government policy has had little practical application. african swine fever, foot-and-mouth disease and cysticercosis are important diseases. the first two are notifiable diseases under tanzania legislation; the last has widespread distribution and ...201323733144
haemoglobin and red cell counts in leptospirosis patients infected with different serovars.the aim of the study was to compare haemoglobin and red cell counts between patients known to be infected with a range of leptospiral serovars.201323740067
cell extract-containing medium for culture of intracellular fastidious bacteria.the culture of fastidious microorganisms is a critical step in infectious disease studies. as a proof-of-concept experiment, we evaluated an empirical medium containing eukaryotic cell extracts for its ability to support the growth of coxiella burnetii. here, we demonstrate the exponential growth of several bacterial strains, including the c. burnetii nine mile phase i and phase ii strains, and c. burnetii isolates from humans and animals. low-oxygen-tension conditions and the presence of small ...201323740722
serosurvey of dogs for human, livestock, and wildlife pathogens, uganda. 201323750507
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