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a clinical approach to determine false positive findings of clinical endometritis by vaginoscopy by the use of uterine bacteriology and cytology in dairy cows.clinical endometritis in dairy cows is defined as mucopurulent or purulent vulvar discharge 21 days or more after parturition. the diagnosis of clinical endometritis is commonly based on vaginal examination. techniques to reduce the proportions of false negative findings have been described. this paper discusses a clinical approach to determine the proportion of false positive findings that might occur by vaginal inspection. the consequences of false positive findings in dairy practice are unnec ...201020615532
cephalexin microspheres for dairy mastitis: effect of preparation method and surfactant type on physicochemical properties of the microspheres.the aim of this study was to evaluate the effects of preparation method and the type of surfactant on the properties of cephalexin (cpx) microspheres in order to obtain delivery systems suitable for the treatment of dairy mastitis. microspheres were obtained using various preparation conditions and their physicochemical characteristics such as size, loading efficiency, morphology, and drug crystallinity were investigated. antibacterial activity of microspheres from the optimum preparation condit ...201020509056
porcine ferrochelatase: the relationship between iron-removal reaction and the conversion of heme to zn-protoporphyrin.at the terminal step of heme biosynthesis, ferrochelatase (fech) catalyzes the insertion of fe2+ into protoporphyrin to form heme. it is located on the inner membrane of the mitochondria of animals. the enzyme inserts divalent metal ions, including fe2+, co2+, and zn2+, into porphyrins in vitro. we have reported that it can remove fe2+ from heme. to characterize the iron-removal reverse activity of fech, we examined its properties in porcine liver and muscle mitochondria, and isolated porcine fe ...201020622448
[purification and characterization of recombinant human lactoferrin expressed in a cattle mammary bioreactor].novel ion exchange adsorbents were synthesized by immobilizing sulfopropyl derivative onto homemade highly cross-linked agarose beads. the effects of different ligand densities (from 0.05 to 0.24 mol/l) on static and dynamic adsorption of the adsorbents were investigated using lysozyme as a model protein. based on these results, rhlf was purified from the transgenic milk by our sp media. 1 ml high density (0.24 mol/l) adsorbent could handle 50 ml rhlf-containing milk. the mass recovery of rhlf w ...201021284219
validation of lactic acid bacteria, lactic acid, and acidified sodium chlorite as decontaminating interventions to control escherichia coli o157:h7 and salmonella typhimurium dt 104 in mechanically tenderized and brine-enhanced (nonintact) beef at the purveyor.after three different outbreaks were linked to the consumption of nonintact meat products contaminated with escherichia coli o157:h7, the u.s. food safety and inspection service published notice requiring establishments producing mechanically tenderized and moisture-enhanced beef products to reassess their respective hazard analysis and critical control point systems, due to potential risk to the consumers. the objective of this study was to validate the use of lactic acid bacteria (lab), acidif ...201021219733
microbial evaluation and public health implications of urine as alternative therapy in clinical pediatric cases: health implication of urine therapy.cultural means of pediatric treatment during ill health is a mainstay in africa, and though urine has been known to contain enteric pathogens, urine therapy is still culturally applicable in some health conditions and also advocated as alternative therapy. the study therefore, is to evaluate the microbial contents and safety of urine.201021293739
giant panda ribosomal protein s14: cdna, genomic sequence cloning, sequence analysis, and overexpression.rps14 is a component of the 40s ribosomal subunit encoded by the rps14 gene and is required for its maturation. the cdna and the genomic sequence of rps14 were cloned successfully from the giant panda (ailuropoda melanoleuca) using rt-pcr technology and touchdown-pcr, respectively; they were both sequenced and analyzed. the length of the cloned cdna fragment was 492 bp; it contained an open-reading frame of 456 bp, encoding 151 amino acids. the length of the genomic sequence is 3421 bp; it conta ...201020957604
behavior of escherichia coli o157:h7 during the manufacture and aging of gouda and stirred-curd cheddar cheeses manufactured from raw milk.this study was conducted to examine the fate of escherichia coli o157:h7 during the manufacture and aging of gouda and stirred-curd cheddar cheeses made from raw milk. cheeses were manufactured from unpasteurized milk experimentally contaminated with one of three strains of e. coli o157:h7 at an approximate population level of 20 cfu/ml. samples of milk, whey, curd, and cheese were collected for enumeration of bacteria throughout the manufacturing and aging process. overall, bacterial counts in ...201021219739
chemo-bacterial synthesis and immunoreactivity of a brain hnk-1 analogue.this work reports the synthesis and the biological validation of a trisaccharide analogue of the hnk-1 epitope. the 3-o-sulfo-β-d-glcpa-(1→3)-β-d-galp-(1→4)-β-d-glcp-allyl has been prepared by enzymatic glucuronylation of allyl lactoside by an engineered recombinant escherichia coli strain followed by a chemoselective sulfation. subsequent covalent attachment of the ozone-oxidised trisaccharide to bovine serum albumin provided a neo-glycoconjugate, which has been interrogated with antibodies spe ...201021176892
antibacterial properties of silver nanoparticles in three different sizes and their nanocomposites with a new waterborne polyurethane.silver nanoparticles (agnps) are strong bactericidal agents but they are also cytotoxic. embedding them in a polymer matrix may reduce their cytotoxic effect. in the present study, agnps in three average sizes were tested for their antibacterial activities and cytotoxicity. nanocomposites from a new waterborne polyetherurethane (peu) ionomer and agnps were prepared without the use of any crosslinker. it was observed that the antibacterial activity of agnps against escherichia coli started at the ...201021187943
transcriptional profiling of immune genes in bovine monocyte-derived macrophages exposed to bacterial antigens.the involvement of toll-like receptors (tlrs) and other immune signalling genes during challenge of bovine macrophages with bacterial products derived from disease-causing bacteria in cattle was investigated. an in vitro cell culture model of bovine monocyte derived macrophages (mdm) was established and these cells were exposed to purified protein derivative (ppd-b) derived from mycobacterium bovis and to lipopolysaccharide (lps) derived from escherichia coli. following 24h incubation, total rna ...201021242003
destruction of escherichia coli o157:h7, salmonella, listeria monocytogenes, and staphylococcus aureus achieved during manufacture of whole-muscle beef jerkyin home-style dehydrators.adequate lethality in jerky manufacture destroys appropriate levels of escherichia coli o157:h7, salmonella, listeria monocytogenes, and staphylococcus aureus. our goal was to evaluate the lethality of four home-style dehydrator processes against these pathogens. whole-muscle beef strips were inoculated with l. monocytogenes (five strains), s. aureus (five strains), or a mixed inoculum of e. coli o157:h7 (five strains) and salmonella (eight strains). after allowing for attachment, strips were ma ...201021219715
udder shape and teat-end lesions as potential risk factors for high somatic cell counts and intra-mammary infections in dairy cows.the association of common bacterial pathogens in milk samples during calving with udder shape or the presence of 'teat-end' lesions was investigated in 240 dairy cows from two herds. sixty-three of 120 cows (53%) in one herd (herd a) and 54/120 animals (45%) in a second herd (herd b) had normal-shaped udders. the remaining animals had udder shapes defined as follows: large pendulous (18% herd a, 26% herd b); large between hindquarter (10% herd a, 17% herd b); overall small (8% herd a, 5% herd b) ...201018951819
vegf-e enhances endothelialization and inhibits thrombus formation on polymeric surfaces.thrombotic complications of long-term blood-contacting devices can be avoided by formation of an endothelial cell layer on the blood-contacting surface. the endothelial cells form a bioactive boundary between the synthetic surface and blood, regulating haemostasis and inflammation. biofunctionalization of synthetic blood-contacting surfaces is necessary to accommodate growth of endothelial cells. vascular endothelial growth factor e (vegf-e) or collagen i may stimulate endothelialization of a po ...201019484771
phylogenetic distribution of virulence genes in escherichia coli isolated from bovine mastitis in iran.one hundred and twenty seven escherichia coli isolates from bovine mastitis were examined to detect the phylogenetic group/subgroups and a selection of virulence associated genes. forty nine (38.58%) isolates belonged to group b1 the remaining isolates fell into four phylogenetic subgroups: a(0) (18.11%), a(1) (26.77%), d(1) (6.29%) and d(2) (10.23%). none of the isolates belonged to b2 group. forty seven (37.00%) isolates were positive for at least one virulence gene, among them f17a was the mo ...201019580980
serogroup distribution and virulence characteristics of sorbitol-negative escherichia coli from food and cattle stool.to (i) study the serogroup distribution and virulence characteristics of non-sorbitol-fermenting escherichia coli isolates from foods of animal origin and cattle faeces and (ii) re-examine the true sorbitol and beta-d-glucuronidase (gud) reactions of sorbitol-negative (sor(-)) strains from macconkey sorbitol agar (smac) to assess their phenotypic similarity with e. coli o157.201019796127
expression of ribonuclease a and ribonuclease n1 in the filamentous fungus neurospora crassa.in this study, we investigated the ability of the fungus neurospora crassa to produce and secrete two ribonucleases: the heterologous bovine rnase a and the endogenous rnase n(1). a set of expression vectors was constructed, each consisting of an rnase a open reading frame under the control of a specific promoter and each with a specific terminator. n. crassa transformants were analyzed at the transcriptional and protein levels. irrespective of the promoter used, all transformants showed an rnas ...201019662399
biological activation of heteropoly complex of molybdotungstosilicate containing lanthanum k10h 3la(simo6w5o39)2x26h2o: spectroscopic approach and microcalorimetry.in this paper, the biological activation of heteropoly complex of molybdotungstosilicate containing lanthanum k(10)h(3)la(simo(6)w(5)o(39))(2)x26h(2)o (law(5)) was investigated by spectroscopic approach and microcalorimetry under the human physiological conditions. fluorescence spectroscopy in combination with uv-vis absorption spectroscopy was employed to investigate the binding of law(5) to bovine serum albumin (bsa). in the mechanism discussion, it was proved that the fluorescence quenching o ...201019680606
a sentinel function for teat tissues in dairy cows: dominant innate immune response elements define early response to e. coli mastitis.escherichia coli intramammary infection elicits localized and systemic responses, some of which have been characterized in mammary secretory tissue. our objective was to characterize gene expression patterns that become activated in different regions of the mammary gland during the acute phase of experimentally induced e. coli mastitis. tissues evaluated were from fürstenburg's rosette, teat cistern (tc), gland cistern (gc), and lobulo-alveolar (la) regions of control and infected mammary glands ...201019727872
modelling the dynamics of intramammary e. coli infections in dairy cows: understanding mechanisms that distinguish transient from persistent infections.the majority of intramammary infections with escherichia coli in dairy cows result in transient infections with duration of about 10 days or less, although more persistent infections (2 months or longer) have been identified. we apply a mathematical model to explore the role of an intracellular mammary epithelial cell reservoir in the dynamics of infection. we included biological knowledge of the bovine immune response and known characteristics of the bacterial population in both transient and p ...201019840536
expression and activity of n-myristoyltransferase in lung inflammation of cattle and its role in neutrophil apoptosis.n-myristoyltransferase (nmt) attaches a 14 carbon fatty acid, myristic acid, to the n-terminal glycine residue of proteins. nmt exists in two isoforms nmt1 and nmt2. myristoylated proteins play critical roles in protein-protein interactions, cell signaling and oncogenesis. although elevated expression of nmt1 has been described in colorectal carcinoma, its expression and roles in normal and inflamed lungs of the cattle are unknown. therefore, we investigated the expression and activity of nmt in ...201019796608
salmonella enterica serovar typhimurium can detect acyl homoserine lactone production by yersinia enterocolitica in mice.luxr-type transcription factors detect acyl homoserine lactones (ahls) and are typically used by bacteria to determine the population density of their own species. escherichia coli and salmonella enterica serovar typhimurium cannot synthesize ahls but can detect the ahls produced by other bacterial species using the luxr homolog, sdia. previously we determined that s. typhimurium did not detect ahls during transit through the gastrointestinal tract of a guinea pig, a rabbit, a cow, 5 mice, 6 pig ...201019820103
characterization of antimicrobial resistance and integrons among escherichia coli isolated from animal farms in eastern china.a total of 182 escherichia coli isolates from animals, environment and workers of dairy cattle, swine and chicken farms in shandong which locates in eastern china, were investigated for antimicrobial resistance as well as prevalence and the transfer mechanisms of integrons. the results revealed isolates from swine and chicken farm exhibited high levels of resistance to antimicrobial agents. the positive rate of gene cassette of class 1 integron in dairy cattle, swine and chicken farms was 5%, 20 ...201019744463
cloning and expression of activation induced cytidine deaminase from bos taurus.activation induced cytidine deaminase is an enzyme crucial to somatic hypermutation and gene conversion, processes that are essential for the diversification of ig v genes. the bovine ig repertoire appears to be diversified by mechanisms that are significantly different to those that operate in humans and mice. this study set out to test the hypothesis that differences in the organization, coding sequence, expression or genomic location of the bovine aicda gene enables the encoded enzyme to cata ...201019766322
effect of changes in number of doses and anatomic location for administration of an escherichia coli bacterin on serum igg1 and igg2 concentrations in dairy cows.to determine effects of injection site on antibody response to j5 escherichia coli bacterin.201020043791
iga and igg antibody responses following systemic immunization of cattle with native h7 flagellin differ in epitope recognition and capacity to neutralise tlr5 signalling.systemic immunization of cattle with h7 flagellin results in induction of both h7-specific iga and igg antibodies but only partially protects against subsequent colonization with escherichia coli o157:h7. recent studies indicate that anti-flagellin antibodies directed against tlr5 binding domains located in the conserved n- and c-terminal domains of flagellin can neutralise tlr5 activation and impair vaccine efficacy. in the current study we determined whether systemic immunization of cattle wit ...201019925908
differential expression of virulence and stress fitness genes between escherichia coli o157:h7 strains with clinical or bovine-biased genotypes.escherichia coli o157:h7 strains can be classified into different genotypes based on the presence of specific shiga toxin-encoding bacteriophage insertion sites. certain o157:h7 genotypes predominate among human clinical cases (clinical genotypes), while others are more frequently found in bovines (bovine-biased genotypes). to determine whether inherent differences in gene expression explain the variation in infectivity of these genotypes, we compared the expression patterns of clinical genotype ...201019880650
yeast cell-wall products containing beta-glucan plus ascorbic acid affect neonatal bos taurus calf leukocytes and growth after a transport stressor.the objectives were to ascertain whether a yeast cell-wall derivative that was 1.8% beta-glucan in combination with ascorbyl-2-polyphosphate could improve innate immunity and mediate transportation stress in neonatal calves, and to compare the 1.8% beta-glucan yeast cell-wall derivative with a more purified yeast cell-wall derivative (70% beta-glucan). treatments were 1) an unsupplemented control (cnt); 2) 113 g of a 1.8% (approximately 2%) beta-glucan derivative of yeast cell walls plus 250 mg ...201019933428
single nucleotide polymorphism analysis of the major tripartite multidrug efflux pump of escherichia coli: functional conservation in disparate animal reservoirs despite exposure to antimicrobial chemotherapy.acrab-tolc imparts a strong intrinsic resistance phenotype to many clinically significant molecules in escherichia coli. this complex is composed of a pump, acrb, and a periplasmic protein, acra, that exports substrates through a common outer membrane porin, tolc. a sequence survey of the pump-specific components, acra and acrb, was conducted on three discrete animal reservoirs: rodents, bovines, and catfish. although two of the reservoirs (bovine and catfish) were agrarian, and antibiotic use ( ...201020038628
treatment of whole blood (wb) and red blood cells (rbc) with s-303 inactivates pathogens and retains in vitro quality of stored rbc.a pathogen inactivation (pi) process has been developed using the frangible anchor linker effector (frale) compound s-303. a series of experiments were performed in whole blood (wb) to measure the level of viral and bacterial inactivation. the results showed that 0.2mm s-303 and 2mm glutathione (gsh) inactivated >6.5 logs of hiv, >5.7 logs of bluetongue virus, >7.0 logs of yersinia enterocolitica, 4.2 logs of serratia marcescens, and 7.5 logs of staphylococcus epidermidis. recent development for ...201019995680
production of shiga-like toxins in viable but nonculturable escherichia coli o157:h7.escherichia coli o157:h7, a causative agent of hemolytic uremic syndrome, can enter into a viable but nonculturable (vbnc) state when under stress. to date, it is unknown whether vbnc cells produce shiga-like toxins (stx). to address this question, we confirmed the expression of the stx1 and stx2 genes and the production of stx in vbnc e. coli o157:h7 cells. to quantitatively assess the production of stx in vbnc cells, we developed a vero-cell microplate cytotoxicity assay based on the correspon ...201019879621
verotoxigenic escherichia coli o157:h7 from swedish cattle; isolates from prevalence studies versus strains linked to human infections--a retrospective study.several cases of human infection caused by verotoxin-producing escherichia coli (vtec) o157:h7 in sweden have been connected with cattle farm visits. between 1996 and 2002, 18 farms were classified as the source of human cases with isolation of ehec (enterohaemorrhagic escherichia coli) after vtec o157:h7 had been isolated from cattle on those farms.201020113494
inhibition of sodium hypochlorite antimicrobial activity in the presence of bovine serum albumin.this study investigated the inhibition of the antimicrobial activity of sodium hypochlorite (naocl) by bovine serum albumin (bsa). the killing of enterococcus faecalis, candida albicans, staphylococcus epidermidis, and escherichia coli by naocl in concentrations from 2% to 0.03% was measured in the presence of bsa in concentrations between 6.7% and 0.1%.201020113787
distribution and antimicrobial resistance of clinical and subclinical mastitis pathogens in dairy cows in rhône-alpes, france.the goal of this study was to estimate the distribution of pathogens, as well as their antimicrobial resistance pattern, in cows affected by clinical or subclinical mastitis in the rhône-alpes region of france. a total of 1770 samples were taken between january 2007 and march 2008, leading to the identification of 1631 bacterial isolates. streptococcus uberis (22.1%), escherichia coli (16%), and coagulase-positive staphylococci (15.8%) were identified as the major causative agents of clinical ma ...201019919286
differences in adherence and virulence gene expression between two outbreak strains of enterohaemorrhagic escherichia coli o157 : h7.the escherichia coli o157 : h7 tw14359 strain was implicated in a multi-state outbreak in north america in 2006, which resulted in high rates of severe disease. similarly, the o157 : h7 rimd0509952 (sakai) strain caused the largest o157 : h7 outbreak to date. both strains were shown to represent divergent phylogenetic lineages. here we compared global gene expression patterns before and after epithelial cell exposure, as well as the ability to adhere to and invade epithelial cells, between the t ...201019892762
immunization of cattle with a combination of purified intimin-531, espa and tir significantly reduces shedding of escherichia coli o157:h7 following oral challenge.enterohemorrhagic escherichia coli (ehec) o157:h7 is a human pathogen that can cause gastrointestinal disease with potentially fatal consequences as a result of systemic shiga toxin activity. cattle are the main reservoir host of ehec o157 and interventions need to be developed that prevent cattle colonization or limit shedding of the organism from this host. ehec o157 predominately colonizes the bovine terminal rectum and requires a type iii secretion system (t3ss) for adherence and persistence ...201019903545
bovine muc1 inhibits binding of enteric bacteria to caco-2 cells.inhibition of bacterial adhesion to intestinal epithelial receptors by the consumption of natural food components is an attractive strategy for the prevention of microbial related gastrointestinal illness. we hypothesised that muc1, a highly glycosylated mucin present in cows' milk, may be one such food component. purified bovine muc1 was tested for its ability to inhibit binding of common enteric bacterial pathogens to caco-2 cells grown in vitro. muc1 caused dose-dependent binding inhibition o ...201019936918
novel myelin penta- and hexa-acetyl-galactosyl-ceramides: structural characterization and immunoreactivity in cerebrospinal fluid.fast migrating cerebrosides (fmc) are derivatives of galactosylceramide (galcer). the structures of the most hydrophobic fmc-5, fmc-6, and fmc-7 were determined by electrospray ionization linear ion-trap mass spectrometry (ms) and nuclear magnetic resonance (nmr) spectroscopy complementing previous nmr spectroscopy and gas chromatography-mass spectrometry to be 3-o-acetyl-sphingosine-galcer derivatives with galactose o-acetyl modifications. fmc-5 and fmc-6 are 3-o-acetyl-sphingosine-2,3,4,6-tetr ...201020154333
blacmy-2-positive inca/c plasmids from escherichia coli and salmonella enterica are a distinct component of a larger lineage of plasmids.large multidrug resistance plasmids of the a/c incompatibility complex (inca/c) have been found in a diverse group of gram-negative commensal and pathogenic bacteria. we present three completed sequences from inca/c plasmids that originated from escherichia coli (cattle) and salmonella enterica serovar newport (human) and that carry the cephamycinase gene blacmy-2. these large plasmids (148 to 166 kbp) share extensive sequence identity and synteny. the most divergent plasmid, peh4h, has lost sev ...201019949054
overexpressed proteins may act as mops removing their ligands from the host cells: a case study of calf pnp.calf purine nucleoside phosphorylase (pnp) was overexpressed in escherichia coli. the basic kinetic parameters of recombinant pnp were found to be similar to the values published previously for non-recombinant pnp from calf spleen. however, upon titration of the recombinant enzyme with the tight-binding multisubstrate analogue inhibitor dfpp-dg, endothermic as well as exothermic signals were obtained. this was not the case for pnp isolated from calf spleen for which only the endothermic process ...201020005207
cross-linking with bifunctional reagents and its application to the study of the molecular symmetry and the arrangement of subunits in hexameric protein oligomers.cross-linking with a bifunctional reagent and subsequent sds gel electrophoresis is a simple but effective method to study the symmetry and arrangement of subunits in oligomeric proteins. in this study, theoretical expressions for the description of cross-linking patterns were derived for protein homohexamers through extension of the method used for tetramers by hajdu et al. (1976). the derived equations were used for the analysis of cross-linking by glutardialdehyde of four protein hexamers: be ...201020005307
the production of soluble and correctly folded recombinant bovine beta-lactoglobulin variants a and b in escherichia coli for nmr studies.the production of soluble and correctly folded eukaryotic proteins in prokaryotic systems has always been hampered by the difference in or lack of cell machinery responsible for folding, post-translation modification and secretion of the proteins involved. in the case of bovine beta-lactoglobulin (blg), a major cow's milk allergen and a protein widely used for protein folding studies, a eukaryotic yeast expression system has been the preferred choice of many researchers, particularly for the pro ...201020018245
virulence profile comparison between lee-negative shiga toxin-producing escherichia coli (stec) strains isolated from cattle and humans.for comparison purposes, the prevalence of 8 virulence markers was investigated, by pcr, in 153 cattle and 47 human locus for enterocyte effacement (lee)-negative shiga toxin-producing escherichia coli (stec) strains isolated in argentina. also, their correlation with severe disease was established. the virulence markers studied comprises 5 fimbrial and nonfimbrial adhesin-encoding genes (fima, iha, efa1, lpfa(o113), and saa) and 3 toxin genes (cdt-v, subab and asta) in addition to the shiga tox ...201020022185
stimulated expression of tnf-alpha and il-8, but not of lingual antimicrobial peptide reflects the concentration of pathogens contacting bovine mammary epithelial cells.we examined if and how mammary epithelial cells (mecs) calibrate and confine the intensity of an inflammatory response elicited by different concentrations of mastitis pathogens. therefore we quantified in primary bovine mec the effect of different e. coli pathogen concentrations upon the abundance of mrna molecules encoding factors of immune defence. induced synthesis of the mrnas encoding tumor necrosis factor alpha and interleukin 8 both clearly correlated with the e. coli dose 1h after stimu ...201019963279
the antibacterial psoriasin is induced by e. coli infection in the bovine udder.human psoriasin (s100a7) has been described as a member of the family of s100 calcium-binding proteins and is over-expressed in patients suffering from psoriasis. the bovine homolog was first identified as a cow-derived respiratory allergen. human psoriasin as well as its bovine homolog exhibit antibacterial activity especially against escherichia coli. during e. coli mastitis, the host defence status is a cardinal factor influencing systemic disease severity, and e. coli mastitis is a common pr ...201020074874
economic values and expected effect of selection index for pathogen-specific mastitis under danish conditions.the objectives of this study were 1) to estimate costs related to 5 different pathogen-specific mastitis traits (susceptibility to different pathogens causing mastitis in dairy cattle) and unspecific mastitis, and 2) to compare selection differentials for an udder health index consisting of 5 different pathogen-specific mastitis traits and lactation average somatic cell count from 5 to 170 d after first calving (lascc170) with another index consisting of 1 unspecific mastitis trait and lascc170. ...201020059934
a high-throughput assay for dna topoisomerases and other enzymes, based on dna triplex formation.we have developed a rapid, high-throughput assay for measuring the catalytic activity (dna supercoiling or relaxation) of topoisomerase enzymes that is also capable of monitoring the activity of other enzymes that alter the topology of dna. the assay utilises intermolecular triplex formation to resolve supercoiled and relaxed forms of dna, the principle being the greater efficiency of a negatively supercoiled plasmid to form an intermolecular triplex with an immobilised oligonucleotide than the ...201019997889
water-solubilised bf(2)-chelated tetraarylazadipyrromethenes.strategic incorporation of sulfonic acid, carboxylic acid or ammonium salt motifs generate water soluble bf(2)-chelated tetraarylazadipyrromethenes which exhibit strong near infra-red (nir) emissions above 720 nm and can be readily imaged in both eukaryotic and prokaryotic cells.201020090964
ppiase domain of trigger factor acts as auxiliary chaperone site to assist the folding of protein substrates bound to the crevice of trigger factor.trigger factor (tf) is the first chaperone encountered by nascent chains in bacteria, which consists of two modules: peptidyl-prolyl-cis/trans-isomerase (ppiase) domain and a crevice built by both n- and c-terminal domains. while the crevice is suggested to provide a protective space over the peptide exit site of ribosome for nascent polypeptides to fold, it remains unclear whether ppiase domain is directly involved in assisting protein folding. here, we introduced structural change into differe ...201020096367
susceptibility of escherichia coli isolated from uteri of postpartum dairy cows to antibiotic and environmental bacteriophages. part ii: in vitro antimicrobial activity evaluation of a bacteriophage cocktail and several antibiotics.the use of pathogenic-specific antimicrobials, as proposed by bacteriophage therapy, is expected to reduce the incidence of resistance development. eighty escherichia coli isolated from uteri of holstein dairy cows were phenotypically characterized for antimicrobial resistance to ampicillin, ceftiofur, chloramphenicol, florfenicol, spectinomycin, streptomycin, and tetracycline by broth microdilution method. the lytic activity of a bacteriophage cocktail against all isolates was performed by a si ...201020059909
a multiplex real-time polymerase chain reaction for simultaneous detection of salmonella spp., escherichia coli o157, and listeria monocytogenes in meat products.to achieve an effective detection of salmonella spp., escherichia coli o157, and listeria monocytogenes in meat products, a multiplex real-time polymerase chain reaction (pcr) coupled with a multipathogen enrichment strategy was developed in this study. pathogen-specific dna sequences in the inva, rfbe, and hlya genes were employed to design primers and taqman probes for identifying salmonella spp., e. coli o157, and l. monocytogenes, respectively. an internal amplification control (iac) utilizi ...201020113204
microspheres of mixed proteins.this paper describes the synthesis of mixed proteinaceous microspheres (mpms) by the sonochemical method. the current fundamental research follows the research of suslick and co-workers who have developed a method by which high-intensity ultrasound is used to make aqueous suspensions of proteinaceous microcapsules filled with water-insoluble liquids.1 by using high-intensity ultrasound, we have synthesized microspheres made of a few different proteins. the three proteins used in the current expe ...201020066692
longitudinal study to investigate vtec o157 shedding patterns in young cattle.individual animal samples were collected from ten vtec o157 positive farms approximately monthly over 11months to investigate the shedding of vtec o157 by youngstock. vtec o157 was isolated from 7.7% of the 6266 samples and 28.9% of the 1383 animals. on six of the farms vtec o157 was isolated at multiple visits from several animals, whereas the remaining four farms had one or two positive animals at any one visit, with vtec isolated from a maximum of four visits. a total of 92 animals were posit ...201020096905
evaluation of the decontamination efficacy of new and reprocessed microfiber cleaning cloth compared with other commonly used cleaning cloths in the hospital.the aim of this study was to investigate the decontamination capacity of 4 different types of cleaning cloths (microfiber cleaning cloth, cotton cloth, sponge cloth, and disposable paper towels) commonly used in hospital in their ability to reduce microbial loads from a surface used dry or wet in new condition. all of the cloths except disposable paper towels were also compared after 10 and 20 times of reprocessing, respectively, at 90 degrees c for 5 minutes in a washing machine.201020123151
influence of wet distiller's grains on prevalence of escherichia coli o157:h7 and salmonella in feedlot cattle and antimicrobial susceptibility of generic escherichia coli isolates.the current research examined the inclusion of 20% wet distiller's grains (wdg) fed with steam-flaked corn (sfc) or dry-rolled corn (drc) in diets fed to feedlot cattle on fecal prevalence of escherichia coli o157:h7 and salmonella. crossbred beef heifers (n = 272; average initial body weight (bw) = 354 kg) were blocked by bw and pen size and randomly assigned to treatment. fecal samples from freshly voided fecal pats were collected from each pen on the day cattle shipped for slaughter (237 feca ...201020132029
prevalence of verotoxin-producing escherichia coli (vtec) in a survey of dairy cattle in najaf, iraq.dairy cattle have been implicated as principal reservoir of verotoxin-producing escherichia coli (vtec), with undercooked ground beef and raw milk being the major vehicles of food borne outbreaks. vtec has been implicated as an etiological agent of individual cases and outbreaks in developed countries. this study was designed to determine the prevalence of vetec in diarrheic dairy calves up to 20 days of age in najaf, iraq.201022347561
genetic parameters for pathogen-specific mastitis resistance in danish holstein cattle.the objective of this study was to estimate heritabilities for and genetic correlations among different pathogen-specific mastitis traits. the traits were unspecific mastitis, which is all mastitis treatments regardless of the causative pathogen as well as mastitis caused by streptococcus dysgalactiae, escherichia coli, coagulase-negative staphylococci (cns), staphylococcus aureus and streptococcus uberis. also groups of pathogens were investigated, gram-negative v. gram-positive and contagious ...200922444442
association of bola-drb3 alleles identified by a sequence-based typing method with mastitis pathogens in japanese holstein cows.the association of the polymorphism of bovine leukocyte antigen (bola-drb3) genes identified by the polymerase chain reaction sequence-based typing (pcr-sbt) method with resistance and susceptibility to mastitis caused by pathogenic bacteria was investigated. blood samples for dna extraction were collected from 194 holstein cows (41 healthy cows and 153 mastitis cows including 24 mixed-infection cows infected with 2 or 3 species of pathogens) from 5 districts of chiba prefecture, japan. sixteen ...200920163613
genomic and cdna cloning, expression, purification, and characterization of chymotrypsin-trypsin inhibitor from winged bean seeds.a 516-bp winged bean chymotrypsin-trypsin inhibitor (wbcti) gene was amplified from genomic dna and cdna isolated from winged bean using a pair of degenerate primers designed on the basis of the amino acid sequences of wbcti. the amplified pcr products were cloned and sequenced to confirm their authenticity. dna sequence analysis of the genomic and cdna clones of wbcti revealed the same nucleotide sequence in the coding region and showed wbcti to be an intron less gene. wbcti was subcloned into ...200920032560
[quantitative risk model for verocytotoxigenic escherichia coli cross-contamination during homemade hamburger preparation].the objective of this study was to develop a quantitative risk model for verocytotoxigenic escherichia coil (vtec) cross-contamination during hamburger preparation at home. published scientific information about the disease was considered for the elaboration of the model, which included a number of routines performed during food preparation in kitchens. the associated probabilities of bacterial transference between food items and kitchen utensils which best described each stage of the process we ...200920085188
temporal and spatial patterns of bovine escherichia coli o157 prevalence and comparison of temporal changes in the patterns of phage types associated with bovine shedding and human e. coli o157 cases in scotland between 1998-2000 and 2002-2004.escherichia coli o157 is an important cause of acute diarrhoea, haemorrhagic colitis and, especially in children, haemolytic uraemic syndrome (hus). incidence rates for human e. coli o157 infection in scotland are higher than most other united kingdom, european and north american countries. cattle are considered the main reservoir for e. coli o157. significant associations between livestock related exposures and human infection have been identified in a number of studies.200920040112
functional cloning and expression of a novel endo-alpha-1,5-l-arabinanase from a metagenomic library.a novel endo-alpha-l-arabinanase gene (arn2) was isolated, and expressed in e. coli in active form. the recombinant enzyme (arn2) had optimum activity at ph 6.0 and 45-50( degrees )c with stability between ph 5.0-8.0 and at temperatures up to 40( degrees )c. the recombinant arn2 catalyzed internal cleavage of alpha-1,5 glycosidic bonds of cm-arabinan, debranched arabinan, linear arabinan, and sugar beet (native) arabinan at rates of decreasing order, and was inactive on wheat arabinoxylan and p- ...200920001905
[differences in pattern of pathogenicity genes in escherichia coli strains producing shiga-like toxin].the detection by pcr of virulence markers in clinical strains of escherichia coli strains producing the shiga-like toxin.200920066775
genomic and phenotypic characterization of escherichia coli isolates recovered from the uterus of puerperal dairy cows.the role of escherichia coli in the pathogenesis of the puerperal uterine infection of the cow is largely unknown. it is proposed that e. coli favors the persistence of arcanobacterium pyogenes and gram-negative bacteria that are pivotal to the establishment of the infection. here, we report the genomic and phenotypic characteristics of 72 e. coli isolates recovered from the uterus of dairy cows with normal puerperium (n = 12; 35 isolates) or clinical metritis (n = 18; 37 isolates), in an attemp ...200919923603
epidemiology and pathogenesis of enterohaemorrhagic escherichia coil.enterohaemorrhagic escherichia coli (ehec) cause diarrhoea, haemorrhagic colitis and the haemolytic uraemic syndrome (hus). ehec cause sporadic, epidemic, and occasionally fatal infections in germany and worldwide. the most probable natural reservoirs of ehec are domestic cattle (in which these organisms cause no disease), but wild animals also excrete ehec asymptomatically. humans (chiefly children) acquire ehec from contact with animals (e. g. in petting zoos) or indirectly, by consuming food ...200919999376
rumen microbiome composition determined using two nutritional models of subacute ruminal acidosis.subacute ruminal acidosis (sara) is a metabolic disease in dairy cattle that occurs during early and mid-lactation and has traditionally been characterized by low rumen ph, but lactic acid does not accumulate as in acute lactic acid acidosis. it is hypothesized that factors such as increased gut permeability, bacterial lipopolysaccharides, and inflammatory responses may have a role in the etiology of sara. however, little is known about the nature of the rumen microbiome during sara. in this stu ...200919783747
characterization of tetracycline- and ampicillin-resistant escherichia coli isolated from the feces of feedlot cattle over the feeding period.the objective of this study was to investigate tetracycline and ampicillin resistance in escherichia coli isolated from the feces of 50 crossbred steers housed in 5 feedlot pens. the steers were not administered antibiotics over a 246-day feeding period. a total of 216 isolates were selected for further characterization. the e. coli isolates were selected on macconkey agar or on macconkey agar amended with ampicillin (50 microg/ml) or tetracycline (4 microg/ml). pulsed-field gel electrophoresis ...200919767846
escherichia coli o157 prevalence in different cattle farm types and identification of potential risk factors.although the prevalence of escherichia coli o157 on cattle farms has been examined extensively, the relationship between this pathogen and farm type has been established only rarely. a large-scale study was designed to determine the prevalence of e. coli o157 in the flemish region of belgium on farms of dairy cattle, beef cattle, mixed dairy and beef cattle, and veal calves. the effect of various factors on the occurrence at the pen level also was evaluated. in 2007, 180 farms were randomly sele ...200919777885
isolation and characterization of bovine herpesvirus 4 (bohv-4) from a cow affected by post partum metritis and cloning of the genome as a bacterial artificial chromosome.bovine herpesvirus 4 (bohv-4) is a gammaherpesvirus with a worldwide distribution in cattle and is often isolated from the uterus of animals with postpartum metritis or pelvic inflammatory disease. virus strain adaptation to an organ, tissue or cell type is an important issue for the pathogenesis of disease. to explore the mechanistic role of viral strain variation for uterine disease, the present study aimed to develop a tool enabling precise genetic discrimination between strains of bohv-4 and ...200919691825
analysis of key molecules of the innate immune system in mammary epithelial cells isolated from marker-assisted and conventionally selected cattle.mastitis is the most prevalent infectious disease in dairy herds. breeding programs considering mastitis susceptibility were adopted as approaches to improve udder health status. in recent decades, conventional selection criteria based on phenotypic characteristics such as somatic cell score in milk have been widely used to select animals. recently, approaches to incorporate molecular information have become feasible because of the detection of quantitative trait loci (qtl) affecting mastitis re ...200919700725
evidence-based semiquantitative methodology for prioritization of foodborne zoonoses.to prioritize an extended list of food- and water-borne zoonoses to allow food safety authorities to focus on the most relevant hazards in the food chain.200919715429
lack of internalization of escherichia coli o157:h7 in lettuce (lactuca sativa l.) after leaf surface and soil inoculation.survival and internalization characteristics of escherichia coli o157:h7 in iceberg, romaine, and leaf lettuce after inoculation of leaf surfaces and soil were determined. a five-strain mixture of e. coli o157:h7 in water and cow manure extract was used as an inoculum for abaxial and adaxial sides of leaves at populations of 6 to 7 log and 4 log cfu per plant. the five strains were individually inoculated into soil at populations of 3 and 6 log cfu/g. soil, leaves, and roots were analyzed for th ...200919833024
bovine muc1 is a highly polymorphic gene encoding an extensively glycosylated mucin that binds bacteria.the bovine muc1 protein is synthesized by mammary epithelial cells and shed into milk as an integral component of the milk fat globule membrane; however, the structure and functions of this mucin, particularly in relation to lactation, are poorly defined. the objectives of this investigation were to investigate the muc1 gene and protein structures in the context of lactation and to test the hypothesis that muc1 has a role in innate immune defense. polymerase chain reaction analysis of genomic dn ...200919762846
the effect of intracellular antioxidant delivery (catalase) on hydrogen peroxide and proinflammatory cytokine synthesis: a new therapeutic horizon.reactive oxygen species synthesized by endothelial cells may be responsible for cell damage and altered physiologic function. after endotoxin stimulation, free radicals including h(2)o(2) are produced. we have developed a method of intracellular drug delivery using albumin microcapsules. catalase would be an excellent compound to alter h(2)o(2) production. however, the large molecular size of catalase limits cellular penetration. endothelial cells have been previously shown to readily phagocytoz ...200919845487
expression of active human sialyltransferase st6galnaci in escherichia coli.background: the presence of terminal, surface-exposed sialic acid moieties can greatly enhance the in vivo half-life of glycosylated biopharmaceuticals and improve their therapeutic efficacy. complete and homogeneous sialylation of glycoproteins can be efficiently performed enzymically in vitro but this process requires large amounts of catalytically active sialyltransferases. furthermore, standard microbial hosts used for large-scale production of recombinant enzymes can only produce small quan ...200919788761
molecular characterization of phosphorylcholine expression on the lipooligosaccharide of histophilus somni.histophilus somni (haemophilus somnus) is an important pathogen of cattle that is responsible for respiratory disease, septicemia, and systemic diseases such as thrombotic meningoencephalitis, myocarditis, and abortion. a variety of virulence factors have been identified in h. somni, including compositional and antigenic variation of the lipooligosaccharide (los). phosphorylcholine (chop) has been identified as one of the components of h. somni los that undergoes antigenic variation. in this stu ...200919682567
lethality of home-style dehydrator processes against escherichia coli o157:h7 and salmonella serovars in the manufacture of ground-and-formed beef jerky and the potential for using a pathogen surrogate in process validation.ground-and-formed beef jerky can be made easily at home with ground beef and kits that include spice, cure, and jerky-forming equipment. ground beef poses inherent risks of illness due to escherichia coli o157:h7 and salmonella contamination, making adequate pathogen lethality important in jerky manufacturing. we evaluated the effectiveness of drying regimes at eliminating e. coli o157:h7 and salmonella in seasoned ground-and-formed beef jerky manufactured with three home-style dehydrators and o ...200919833027
osteopontin: an early innate immune marker of escherichia coli mastitis harbors genetic polymorphisms with possible links with resistance to mastitis.mastitis is the most important disease in dairy cows and it causes significant lost of profit to producers. identification of the genes, and their variants, involved in innate immune responses is essential for the understanding of this inflammatory disease and to identify potential genetic markers for resistance to mastitis. the progeny of dairy cows would benefit from receiving favourable alleles that support greater resistance to infection, thus reducing antibiotic use. this study aims to iden ...200919765294
phosphorylated proteins of the mammalian mitochondrial ribosome: implications in protein synthesis.mitochondria, the powerhouse of eukaryotic cells, have their own translation machinery that is solely responsible for synthesis of 13 mitochondrially encoded protein subunits of oxidative phosphorylation complexes. phosphorylation is a well-known post-translational modification in regulation of many processes in mammalian mitochondria including oxidative phosphorylation. however, there is still very limited knowledge on phosphorylation of mitochondrial ribosomal proteins and their role(s) in rib ...200919702336
validation of iq-check e. coli o157:h7 real-time pcr test kit for detection of escherichia coli o157:h7 in selected foods.iq-check e. coli o157:h7 (bio-rad laboratories, hercules, ca) is a real-time pcr kit for detection of e. coli o157:h7 from selected foods. specific fluorescent oligonucleotide probes are used to detect target dna during the amplification, by hybridizing to the amplicons. these fluorescent probes are linked to a fluorophore which fluoresces only when hybridized to the target sequence. three foods (ground beef, apple cider, fresh spinach) were selected to compare the performance of iq-check e. col ...200919714978
shiga toxin kills epithelial cells isolated from distal but not proximal part of mouse colon.shiga toxins (stxs) are major virulence factors produced by enterohemorrhagic escherichia coli o157:h7 colonizing the human and cattle intestines. we previously demonstrated that recombinant binding subunits (stx1b) bound to the mucosal epithelium of the distal but not that of the proximal part of the mouse colon. here we developed a method for isolating colon epithelial cells from the proximal and distal parts separately. enrichment of epithelial cells was confirmed by the expression of cytoker ...200919721242
survival of escherichia coli o157:h7 in ground beef after sublethal heat shock and subsequent isothermal cooking.heat shock of escherichia coli o157:h7 in broth media reportedly leads to enhanced survival during subsequent heating in broth medium or ground beef. survival of e. coli o157:h7 during slow cooking thus may be enhanced by prior exposure to sublethal heat shock conditions, thereby jeopardizing the safety of slow-cooked products such as beef roasts. this study examined the effect of heat shocking e. coli o157:h7-inoculated lean (6 to 9% fat) ground beef on the survival of the pathogen in the same ...200919722409
virulence genes and molecular typing of different groups of escherichia coli o157 strains in cattle.characterization of an escherichia coli o157 strain collection (n = 42) derived from healthy hungarian cattle revealed the existence of diverse pathotypes. enteropathogenic e. coli (epec; eae positive) appeared to be the most frequent pathotype (n = 22 strains), 11 o157 strains were typical enterohemorrhagic e. coli (ehec; stx and eae positive), and 9 o157 strains were atypical, with none of the key stx and eae virulence genes detected. ehec and epec o157 strains all carried eae-gamma, tir-gamma ...200919684174
evaluation of the control of pathogen load by an anti-salmonella bacterium in a herd of cattle with persistent salmonella infection.to determine whether an anti-salmonella bacterium is involved in control of pathogen load in persistently infected cattle herds.200919119953
experimental infection in calves with a specific subtype of verocytotoxin-producing escherichia coli o157:h7 of bovine origin.in sweden, a particular subtype of verocytotoxin-producing escherichia coli (vtec) o157:h7, originally defined as being of phage type 4, and carrying two vtx2 genes, has been found to cause the majority of reported human infections during the past 15 years, including both sporadic cases and outbreaks. one plausible explanation for this could be that this particular subtype is better adapted to colonise cattle, and thereby may be excreted in greater concentrations and for longer periods than othe ...200919878595
characterization of the effects of salicylidene acylhydrazide compounds on type iii secretion in escherichia coli o157:h7.recent work has highlighted a number of compounds that target bacterial virulence by affecting gene regulation. in this work, we show that small-molecule inhibitors affect the expression of the type iii secretion system (t3ss) of escherichia coli o157:h7 in liquid culture and when this bacterium is attached to bovine epithelial cells. inhibition of t3ss expression resulted in a reduction in the capacity of the bacteria to form attaching and effacing lesions. our results show that there is marked ...200919635828
the design, synthesis and evaluation of hypoxia-activated pro-oligonucleotides.hypoxia-activated pro-oligonucleotides were synthesized through the commercial phosphoramidite method, and could be readily cleaved to form normal oligos with good hypoxia selectivity in vitro under the effect of reductases, as well as in tumor cell extract.200919587918
escherichia coli o157:h7 strains that persist in feedlot cattle are genetically related and demonstrate an enhanced ability to adhere to intestinal epithelial cells.a longitudinal study was conducted to investigate the nature of escherichia coli o157:h7 colonization of feedlot cattle over the final 100 to 110 days of finishing. rectal fecal grab samples were collected from an initial sample population of 788 steers every 20 to 22 days and microbiologically analyzed to detect e. coli o157:h7. the identities of presumptive colonies were confirmed using a multiplex pcr assay that screened for gene fragments unique to e. coli o157:h7 (rfbe and flic(h7)) and oth ...200919617387
separation of acidic and basic proteins by ce with ctab additive and its applications in peptide and protein profiling.in this paper, we report a very simple but efficient cationic micellar ce method for protein analysis in complex samples without any modification for the capillary wall. it was found that increased concentration (>or=2 mm) of ctab additive in electrophoretic buffer can effectively suppress the wall adsorption of both acidic and basic proteins. the separation was improved with buffer ph decreasing from 6.0 to 3.0. by using a buffer containing 2 mm ctab at ph 3.0, nine proteins with a wide range o ...200919582714
absence of escherichia coli phylogenetic group b2 strains in humans and domesticated animals from jeonnam province, republic of korea.multiplex pcr analyses of dnas from genotypically unique escherichia coli strains isolated from the feces of 138 humans and 376 domesticated animals from jeonnam province, south korea, performed using primers specific for the chua and yjaa genes and an unknown dna fragment, tspe4.c2, indicated that none of the strains belonged to e. coli phylogenetic group b2. in contrast, phylogenetic group b2 strains were detected in about 17% (8 of 48) of isolates from feces of 24 wild geese and in 3% (3 of 9 ...200919592524
validation of ground-and-formed beef jerky processes using commercial lactic acid bacteria starter cultures as pathogen surrogates.beef jerky has been linked to multiple outbreaks of salmonellosis and escherichia coli o157:h7 infection over the past 40 years. with increasing government scrutiny of jerky-making process lethality, a simple method by which processors can easily validate the lethality of their ground-and-formed beef jerky process against salmonella' and e. coli o157:h7 is greatly needed. previous research with whole-muscle beef jerky indicated that commercial lactic acid bacteria (lab) may be more heat resistan ...200919610334
effect of tenderizers combined with organic acids on escherichia coli o157:h7 thermal resistance in non-intact beef.non-intact beef products include beef cuts that have been ground, mechanically tenderized, restructured, or have been injected with solutions to enhance tenderness and/or flavor. this study examined the effects of tenderizing salts and organic acids on thermal inactivation of escherichia coli o157:h7 in a ground beef model system simulating non-intact beef products. ground beef (95% lean; 700 g batches) was mixed (2 min) with nothing (c) or solutions (22 ml) of water (wa), calcium ascorbate (caa ...200919493583
ctx-m-type beta-lactamase in escherichia coli isolated from sick animals in korea.about 408 escherichia coli were isolated from sick farm animals and pets during 2003-2006. of these isolates, four strains showed resistance to third-generation cephalosporins. the bla(ctx-m-14) gene was encountered in three e. coli strains, each of which were isolated from two cows and a dog, respectively, and bla(ctx-m-15) was identified in an e. coli isolated from a pig. all bla(ctx-m) genes were found to be transferred. the pulsed-field gel electrophoresis pattern indicated that the ctx-m-ty ...200919496675
identification of new cyp2c19 variants exhibiting decreased enzyme activity in the metabolism of s-mephenytoin and omeprazole.although many cases of interindividual variation in the metabolism of cyp2c19 drugs are explained by the cyp2c19*2, *3, and *17, a wide range of metabolic variation still occurs in people who do not carry these genetic variants. the objectives of this study were to identify new genetic variants and to characterize functional consequences of these variants in metabolism of cyp2c19 substrates. in total, 21 single-nucleotide polymorphisms including three new coding variants, v394m, e405k, and d256n ...200919661214
role of the general base glu-268 in nitroglycerin bioactivation and superoxide formation by aldehyde dehydrogenase-2.mitochondrial aldehyde dehydrogenase-2 (aldh2) plays an essential role in nitroglycerin (gtn) bioactivation, resulting in formation of no or a related activator of soluble guanylate cyclase. aldh2 denitrates gtn to 1,2-glyceryl dinitrate and nitrite but also catalyzes reduction of gtn to no. to elucidate the relationship between aldh2-catalyzed gtn bioconversion and established aldh2 activities (dehydrogenase, esterase), we compared the function of the wild type (wt) enzyme with mutants lacking ...200919506075
molecular analysis of escherichia coli from retail meats (2002-2004) from the united states national antimicrobial resistance monitoring system.the origins and virulence potential of meat product-associated escherichia coli are undefined.200919508167
minor modification to official method 2000.14, reveal for e. coli o157:h7 test in selected foods and environmental swabs (20-hour method): validation of the test for 375 g raw beef samples.a lateral flow immunoassay for escherichia coli o157:h7 (reveal e. coli o157:h7, 20-h version), previously validated for 25 g raw ground beef, raw beef cubes, apple cider, lettuce rinse, and environmental swab samples, has been validated for use in testing 375 g samples of raw ground beef and raw beef cubes. the reveal method, including culture confirmation of positive immunoassay results, was evaluated in comparison to the current reference culture procedure of the u.s. department of agricultur ...200919485202
functions of manduca sexta hemolymph proteinases hp6 and hp8 in two innate immune pathways.serine proteinases in insect plasma have been implicated in two types of immune responses; that is, activation of prophenoloxidase (propo) and activation of cytokine-like proteins. we have identified more than 20 serine proteinases in hemolymph of the tobacco hornworm, manduca sexta, but functions are known for only a few of them. we report here functions of two additional m. sexta proteinases, hemolymph proteinases 6 and 8 (hp6 and hp8). hp6 and hp8 are each composed of an amino-terminal clip d ...200919487692
the escherichia coli o157:h7 ehab autotransporter protein binds to laminin and collagen i and induces a serum iga response in o157:h7 challenged cattle.enterohaemorrhagic escherichia coli (ehec) are a subgroup of shiga toxin-producing e.  coli that cause gastrointestinal disease with the potential for life-threatening sequelae. cattle serve as the natural reservoir for ehec and outbreaks occur sporadically as a result of contaminated beef and other farming products. while certain ehec virulence mechanisms have been extensively studied, the factors that mediate host colonization are poorly defined. previously, we identified four proteins (ehaa,b ...200919508554
[expression of the genes cela and xyla isolated from a fragment of metagenomic dna in escherichia coli].the glycosyl hydrolase genes cel5a and xyl3a previously isolated by ourselves within a fragment of dna from the methagenomic library of cow rumen microflora dna were sub-cloned and expressed in e. coli. the recombinant proteins cel5a and xyl3a were purified and characterized. cellulase cel5a belongs to the family 5 glycosyl hydrolases and is a one-module 38.2 kda enzyme that hydrolyses the 1,4-glycoside bonds of soluble cellulose substrates and amorphous cellulose, showing its maximal activity ( ...200919517808
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