Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| molecular cloning, expression and modelling of cat allergen, cystatin (fel d 3), a cysteine protease inhibitor. | cats are an important source of indoor allergens. however, only two cat allergens, fel d 1 and albumin, have been cloned and sequenced. ige antibodies to fel d 1 and albumin do not fully account for ige responses to cat and there is good immunochemical evidence that cats produce other allergens. | 2001 | 11529899 |
| irreversible inhibition of pig kidney copper-containing amine oxidase by sodium and lithium ions. | copper amine oxidase was found to be inhibited in a complex way by small alkali metal ions. classic enzyme kinetic studies showed that li+ and na+ were weak noncompetitive inhibitors, whereas the larger alkali metals k+, rb+ and cs+ were not inhibitors. however, freezing in the presence of na+ or li+ surprisingly resulted in complete and irreversible inactivation. in the case of li+, it was possible to show that one ion per subunit was retained permanently in the inactivated enzyme, suggesting a ... | 2001 | 11532005 |
| quinolone resistance in potentially pathogenic and non-pathogenic escherichia coli strains isolated from healthy ruminants. | quinolone resistance was studied in potentially pathogenic and non-pathogenic escherichia coli strains from healthy ruminants. in cattle, 5.9% of the strains were resistant to nalidixic acid and 4.9% were resistant to enrofloxacin and ciprofloxacin, whereas in sheep and goats only 0.5% and 1.4%, respectively, of the strains were resistant to nalidixic acid and none to fluoroquinolones. most of the strains resistant to quinolones were non-pathogenic strains isolated from cattle. however, the resu ... | 2001 | 11533010 |
| exposure of escherichia coli to intestinal myoelectrical activity-related electric field induces resistance against subsequent uv(254 nm) (uvc) irradiation. | survival of escherichia coli k-12 ab1157 irradiated with uvc (uv(254 nm)) was enhanced after pre-treatment with a low-tension electric field (ef). the ef used was identical to the electrical field generated by the small intestine (myoelectrical migrating complex--mmc), registered in a healthy calf and transmitted into the memory of an ef generator. the ef emitted by the generator was transmitted via electrodes placed in shaken bacterial cultures. the protective effects of the ef on the e. coli s ... | 2001 | 11551485 |
| the large subunit of the mammalian mitochondrial ribosome. analysis of the complement of ribosomal proteins present. | identification of all the protein components of the large subunit (39 s) of the mammalian mitochondrial ribosome has been achieved by carrying out proteolytic digestions of whole 39 s subunits followed by analysis of the resultant peptides by liquid chromatography and mass spectrometry. peptide sequence information was used to search the human est data bases and complete coding sequences were assembled. the human mitochondrial 39 s subunit has 48 distinct proteins. twenty eight of these are homo ... | 2001 | 11551941 |
| the mechanism of carbonate killing of escherichia coli. | to define the mechanism of carbonate killing in escherichia coli. | 2001 | 11555203 |
| a rapid twofold dilution method for microbial enumeration and resuscitation of uninjured and sublethally injured bacteria. | a rapid and simple method for enumerating uninjured and sublethally injured bacterial cells, the twofold dilution method (2fd), was developed and evaluated. | 2001 | 11555210 |
| evidence for transfer of cmy-2 ampc beta-lactamase plasmids between escherichia coli and salmonella isolates from food animals and humans. | escherichia coli is an important pathogen that shows increasing antimicrobial resistance in isolates from both animals and humans. our laboratory recently described salmonella isolates from food animals and humans that expressed an identical plasmid-mediated, ampc-like beta-lactamase, cmy-2. in the present study, 59 of 377 e. coli isolates from cattle and swine (15.6%) and 6 of 1,017 (0.6%) isolates of human e. coli from the same geographic region were resistant to both cephamycins and extended- ... | 2001 | 11557460 |
| formation of the 1,n2-glyoxal adduct of deoxyguanosine by phosphoglycolaldehyde, a product of 3'-deoxyribose oxidation in dna. | oxidation of deoxyribose in dna results in the formation of a variety of electrophilic products that have the potential to react with nucleobases to form adducts. we now report that 2-phosphoglycolaldehyde, a model for the 3'-phosphoglycolaldehyde residue generated by 3'-oxidation of deoxyribose in dna, reacts with dg and dna to form the diastereomeric 1,n2-glyoxal adducts of dg, 3-(2-deoxy-beta-d-erythro-pentofuransyl)-6,7-dihydro-6,7-dihydroxyimidazo[1,2-a]purine-9(3h)-one. the glyoxal adducts ... | 2001 | 11559039 |
| dual mode recognition of two isoacceptor trnas by mammalian mitochondrial seryl-trna synthetase. | animal mitochondrial translation systems contain two serine trnas, corresponding to the codons agy (y = u and c) and ucn (n = u, c, a, and g), each possessing an unusual secondary structure; trna(gcu)(ser) (for agy) lacks the entire d arm, whereas trna(uga)(ser) (for ucn) has an unusual cloverleaf configuration. we previously demonstrated that a single bovine mitochondrial seryl-trna synthetase (mt serrs) recognizes these topologically distinct isoacceptors having no common sequence or structure ... | 2001 | 11577083 |
| titration of low k(d) binding sites: binding of arginine analogs to nitric oxide synthases. | spectrophotometrically monitored ligand titration is an important method for the determination of equilibrium dissociation constants (k(d)) from nitric oxide synthases (nos). low k(d) sites such as the tetrahydrobiopterin and arginine binding sites present difficulties in that experiments often require enzyme concentrations of the same magnitude as the k(d). an analytical method based on computer simulation is described that allows the estimation of k(d) values without an independent means of mo ... | 2001 | 11587559 |
| overexpression of human insulin-like growth factor-i promotes new tissue formation in an ex vivo model of articular chondrocyte transplantation. | articular cartilage, the tissue that forms the gliding surface of joints, has a poor regenerative capacity. insulin-like growth factor-i (igf-i) is a polypeptide that is anabolic and mitogenic for cartilage. transfection of articular chondrocytes with an expression plasmid vector containing the cdna for human igf-i under the control of the cytomegalovirus promoter/enhancer led to expression of the transgene and synthesis of biologically relevant amounts of igf-i protein. transplantation of trans ... | 2001 | 11593356 |
| structural and functional characterization of human nad kinase. | nadp is essential for biosynthetic pathways, energy, and signal transduction. its synthesis is catalyzed by nad kinase. very little is known about the structure, function, and regulation of this enzyme from multicellular organisms. we identified a human nad kinase cdna and the corresponding gene using available database information. a cdna was amplified from a human fibroblast cdna library and functionally overexpressed in escherichia coli. the obtained cdna, slightly different from that deposit ... | 2001 | 11594753 |
| effect of irradiation temperature on inactivation of escherichia coli o157:h7 and staphylococcus aureus. | the resistance of escherichia coli o157:h7 and staphylococcus aureus in ground beef to gamma radiation was significantly (p < 0.05) higher at subfreezing temperatures than above freezing. ground beef was inoculated (ca. 2 x 10(8) cfu/g) with five isolates of either e. coli o157:h7 or s. aureus and subdivided into 25-g samples, vacuum packaged in barrier pouches, and tempered to 20, 12, 4, 0, -4, -12, -20, -30, -40, or -76 degrees c before gamma irradiation. the studies were repeated twice. the d ... | 2001 | 11601718 |
| bacteremia associated with naturally occuring acute coliform mastitis in dairy cows. | to determine the incidence of bacteremia in dairy cows with naturally occurring acute coliform mastitis (acm) with a wide range of disease severity. | 2001 | 11601796 |
| rotavirus 2/6 virus-like particles administered intranasally in mice, with or without the mucosal adjuvants cholera toxin and escherichia coli heat-labile toxin, induce a th1/th2-like immune response. | we investigated the rotavirus-specific lymphocyte responses induced by intranasal immunization of adult balb/c mice with rotavirus 2/6 virus-like particles (2/6-vlps) of the bovine rf strain, by assessing the profile of cytokines produced after in vitro restimulation and serum and fecal antibody responses. the cytokines produced by splenic cells were first evaluated. intranasal immunization with 50 microg of 2/6-vlps induced a high serum antibody response, including immunoglobulin g1 (igg1) and ... | 2001 | 11602741 |
| e. coli methionine sulfoxide reductase with a truncated n terminus or c terminus, or both, retains the ability to reduce methionine sulfoxide. | the monomeric peptide methionine sulfoxide reductase (msra) catalyzes the irreversible thioredoxin-dependent reduction of methionine sulfoxide. the crystal structure of msras from escherichia coli and bos taurus can be described as a central core of about 140 amino acids that contains the active site. the core is wrapped by two long n- and c-terminal extended chains. the catalytic mechanism of the e. coli enzyme has been recently postulated to take place through formation of a sulfenic acid inte ... | 2001 | 11604533 |
| a novel locus of enterocyte effacement (lee) pathogenicity island inserted at phev in bovine shiga toxin-producing escherichia coli strain o103:h2. | we describe a locus of enterocyte effacement (lee) which is part of a new pathogenicity island (pai) detected in the bovine shiga toxin-producing escherichia coli strain rw1374 (o103:h2). this pai is at least 80 kb in size and inserted in the vicinity of the phev trna gene at 67 min of the e. coli chromosome. furthermore, the pai differs from the previously described lees by unique flanking regions at both sides, which harbor one copy each of an insertion element in an inverted orientation that ... | 2001 | 11682182 |
| colostral whey concentrate supplement increases complement activity in the sera of neonatal calves. | we evaluated the effect of a commercial bovine colostral whey on the complement-mediated immune responses of calves. two groups of neonatal calves were fed, in addition to whole milk (wm) and pooled colostrum (pc), different amounts of a commercial immunoglobulin concentrate made from pooled colostral whey (ig-c) for the first two feedings post natum. the control group was fed wm and pc only. serum samples were obtained at the ages of 2, 7, 14 and 30 d. bacteriolytic activity against complement- ... | 2001 | 11694039 |
| ancestral divergence, genome diversification, and phylogeographic variation in subpopulations of sorbitol-negative, beta-glucuronidase-negative enterohemorrhagic escherichia coli o157. | the o157:h7 lineage of enterohemorrhagic escherichia coli is a geographically disseminated complex of highly related genotypes that share common ancestry. the common clone that is found worldwide carries several markers of events in its evolution, including markers for acquisition of virulence genes and loss of physiological characteristics, such as sorbitol fermentation ability and beta-glucuronidase production. populations of variants that are distinct with respect to motility and the sorbitol ... | 2001 | 11698378 |
| prevalence of foodborne pathogens in bulk tank milk. | bulk tank milk from 131 dairy herds in eastern south dakota and western minnesota was examined for the presence of for foodborne pathogens. campylobacter jejuni, shiga-toxin producing escherichia coli, listeria monocytogenes, salmonella spp., and yersinia enterocolitica were detected in 9.2, 3.8, 4.6, 6.1, and 6.1% of bulk tank milk samples, respectively. thirty-five of 131 (26.7%) bulk tank milk samples contained one or more species of pathogenic bacteria. isolates of salmonella belonged to gro ... | 2001 | 11699446 |
| analysis of the inhibition of mammalian thioredoxin, thioredoxin reductase, and glutaredoxin by cis-diamminedichloroplatinum (ii) and its major metabolite, the glutathione-platinum complex. | several studies have demonstrated a correlation between cellular toxicity of cis-diamminedichloroplatinum (ii) (cisplatin, cddp) and inhibited intracellular activity of the thioredoxin system, i.e., thioredoxin (trx), thioredoxin reductase (trxr), and nadph. conversely, increased cellular activity of the trx system confers resistance to cddp. in this study, we have analyzed the interaction of cddp with trx and trxr in order to clarify the mechanism. the inhibition with time-dependent kinetics by ... | 2001 | 11705695 |
| prevalence of e coli o157 in dairy cows presented for slaughter in victoria. | 2001 | 11712712 | |
| endometritis in postparturient cattle associated with bovine herpesvirus-4 infection: 15 cases. | suppurative, ulcerative endometritis associated with bovine herpesvirus-4 (bhv-4) infection was identified in 15 postparturient dairy cows from 5 separate dairies. characteristic eosinophilic to amphophilic intranuclear viral inclusion bodies were identified within degenerate endometrial lining epithelium and endothelial cells. bovine herpesvirus-4 was confirmed as the etiology by a combination of fluorescent antibody assays, viral isolation, heminested pcr, ultrastructural examination of the ut ... | 2001 | 11724141 |
| contamination of beef chucks with escherichia coli during carcass breaking. | samples were obtained by swabbing the whole of the chuck portion on each of the first 500 sides that entered a beef carcass breaking process and the whole of the outer surface of each of the chuck primal cuts that were prepared from those portions. swabs obtained from groups of 10 sides or cuts that entered or emerged from the process consecutively were combined, and the coliforms and escherichia coli recovered from each group were enumerated. coliforms and e. coli were recovered only sporadical ... | 2001 | 11726167 |
| sensitivity of shiga toxin-producing escherichia coli (stec) strains for colicins under different experimental conditions. | twenty escherichia coli strains producing well-characterised colicins were tested for their inhibitory activity against five shiga toxin-producing e. coli (stec) strains using different media under aerobic and anaerobic conditions. the five stec strains used were of serotype o26, o111, o128, o145 and o157:h7 which are frequently isolated serotypes associated with disease in humans. the main route of infection for humans is through the eating of badly cooked or handled beef. the major reservoir f ... | 2001 | 11731144 |
| sample preparation methods for pcr detection of escherichia coli o157:h7, salmonella typhimurium, and listeria monocytogenes on beef chuck shoulder using a single enrichment medium. | to improve the utility of the polymerase chain reaction (pcr) for food samples, methods for preparing template dna were developed to remove pcr inhibitors. beef chuck shoulder medallions, artificially contaminated, individually or in combination, with escherichia coli serotype o157:h7 strain fsis 45753-35, salmonella typhimurium dt104 strain 13hp, or listeria monocytogenes strain scott a at concentrations of 10, 1 and 0.5 cfu/cm(2)were swabbed with a sponge, and the sponges were enriched for 18 ... | 2001 | 11735298 |
| clinical and bacteriological aspects on the use of oxytetracycline and flunixin in primiparous cows with induced retained placenta and post-partal endometritis. | retention of the fetal membranes and post-partal endometritis (rfm) are common problems in dairy cows. treatment often includes manual removal of the placenta in combination with antibiotic treatment. earlier studies have shown that cows with endometritis post-partum have a strong tendency to recover spontaneously. the present study focused on treatments of post-partal endometritis with the prostaglandin synthesis inhibitor, flunixin (f) either alone or combined with oxytetracycline (t). the stu ... | 2001 | 11885742 |
| escherichia coli o157 infections and unpasteurised milk. | we report on two children with escherichia coli o157 infection, one of whom developed haemolytic uraemic syndrome (hus). both had drunk raw cows or goats milk in the week before their illness. molecular subtyping identified a sorbitol fermenting escherichia coli o157:h isolate from a dairy cow. this isolate differed from shiga toxin producing o157:h strains isolated from the 6 year old boy with hus. this result underlines the need to search for other causes of infection, despite documented con ... | 2001 | 11891383 |
| [rapid detection of enterohemorrhagic escherichia coli in food with multiplex pcr assay]. | rapid detection of enterohemorrhagic escherichia coli (ehec) in food was achieved by using multiplex pcr assay. the assay was designed to amplify the 1109, 302 and 228 bp regions of corresponding virulence genes eaea, hlyab, slt1 and/or slt2, by using specific primers for each one reaction. in 60 ehec and other strains, the above three virulence gene sequences were co-amplified from dna isolated from 12 ehec o157:h7 strains, 1 o26:h11 strain and 1 o111:h8 strain; eaea sequence was amplified from ... | 2001 | 12561602 |
| microbiological contamination of raw beef trimmings and ground beef. | to survey the microbiological quality of beef trimmings and final-ground beef, samples were collected from eight commercial grinding facilities, including trimmings from fed-cattle, culled-beef cows, culled-dairy cows, imported-beef trimmings and finished-ground products. trim samples (core and purge) and ground product samples (n=586) were evaluated for aerobic plate (apc), total coliform (tcc), escherichia coli (ecc) and staphylococcus aureus counts and the presence of salmonella spp. and list ... | 2000 | 22061902 |
| a longitudinal study of shiga-toxigenic escherichia coli (stec) prevalence in three australian diary herds. | over a 12 month period, 588 cattle faecal samples and 147 farm environmental samples from three dairy farms in southeast queensland were examined for the presence of shiga-toxigenic escherichia coli (stec). samples were screened for shiga toxin gene (stx) using pcr. samples positive for stx were filtered onto hydrophobic grid membrane filters and stec identified and isolated using colony hybridisation with a stx-specific dna probe. serotyping was performed to identify serogroups commonly associa ... | 2000 | 10665540 |
| cloning and expression of glycolipid transfer protein from bovine and porcine brain. | glycolipid transfer protein (gltp) is a small (23-24 kda), basic protein (pi congruent with 9.0) that accelerates the intermembrane transfer of various glycolipids. here, we report the first cloning of cdnas that encode the bovine and porcine gltps. the cdna open reading frame for bovine gltp was constructed by bridge-overlapping extension polymerase chain reaction (pcr) after obtaining partial coding cdna clones by hot start, seminested, and rapid amplification of cdna ends-pcr. the cdna open r ... | 2000 | 10671554 |
| subtypes of intimin among non-toxigenic escherichia coli from diarrheic calves in brazil. | one hundred and five strains of escherichia coli that were isolated from calves with diarrhea in the state of são paulo, brazil, and were negative for enterotoxins and cytotoxins, were examined for the eae gene. four (3.8%) strains were positive by polymerase chain reaction (pcr) and were shown to produce intimin by using western blot with specific antiserum against the conserved n-terminal region of intimin. subtyping of the intimins was done by pcr with specific primers and by western blot wit ... | 2000 | 10680651 |
| clonal turnover of enterohemorrhagic escherichia coli o157:h7 in experimentally infected cattle. | a total of 401 enterohemorrhagic escherichia coli (ehec) o157:h7 isolates from two experimentally infected calves were analyzed using molecular biological methods. genetic differences detected by pulsed-field gel electrophoresis were observed between the inoculated and recovered strains as early as 1 day post inoculation. the loss of the inoculated clone was observed in one calf. replication and dissemination of the ehec o157:h7 strains that mutated in cattle may result in the diversification of ... | 2000 | 10689170 |
| effect of endotoxin challenge on hepatic 5'-deiodinase activity in cattle. | thyroid status is compromised in a variety of acute and chronic infections and toxin-mediated disease states. conversion of thyroxine (t4) into the metabolically active hormone, triiodothyronine (t3), is catalyzed by 5'-deiodinase (5'd). our objective was to determine the effect of endotoxin (lps) challenge with and without l-arginine (arg) infusion on hepatic activity of 5'd and plasma concentrations of t4 and t3. in a 2 x 2 factorial, beef heifers (275-310 kg b.wt.) were fed low (8% cp; 6.5 kg ... | 2000 | 10701770 |
| differential induction of complement fragment c5a and inflammatory cytokines during intramammary infections with escherichia coli and staphylococcus aureus. | the prompt recruitment of neutrophils to the site of infection is essential for the defense of the bovine mammary gland against invading pathogens and is determinant for the outcome of the infection. escherichia coli is known to induce clinical mastitis, characterized by an intense neutrophil recruitment leading to the eradication of the bacteria, whereas staphylococcus aureus induces subclinical mastitis accompanied by a moderate neutrophil recruitment and the establishment of chronic mastitis. ... | 2000 | 10702487 |
| catalase deficiency in staphylococcus aureus subsp. anaerobius is associated with natural loss-of-function mutations within the structural gene. | degenerate oligonucleotide primers based on internal peptide sequences obtained by hplc from purified staphylococcus aureus catalase were used to locate the s. aureus and s. aureus subsp. anaerobius kat regions by pcr. southern hybridization analysis with a probe derived from a 1.1 kb pcr-amplified fragment showed that a single copy of the putative catalase gene was present in the s. aureus and s. aureus subsp. anaerobius chromosome. the nucleotide sequence of s. aureus kata revealed a 1518 bp o ... | 2000 | 10708385 |
| dihydrofolate influences the activity of escherichia coli dihydrofolate reductase synthesised de novo. | the folding of proteins into their native structures is known to depend on molecular chaperones. however, other ligands or cofactors which still require characterisation are also likely to influence protein folding. the intention of this study was to reveal how the folding of an enzyme, escherichia coli dihydrofolate reductase, was affected by a substrate ligand, i.e. dihydrofolate. the enzyme was synthesised by coupled transcription/translation in a bacterial cell-free system. correct folding o ... | 2000 | 10716630 |
| effects of sodium fertilizers and supplements on milk production and mammary gland health. | a series of experiments was conducted to investigate the effects of sodium fertilizers and supplements on the milk production and mammary health of dairy cows. in expt 1, where sodium fertilizer was applied to productive pastures consisting mainly of the natrophile perennial rye-grass, the herbage sodium content and the milk yield of cows was increased and milk somatic cell count (scc) reduced. in expt 2, which used pastures containing less productive, natrophobic grasses and broad-leaved plants ... | 2000 | 10717838 |
| biosynthesis of heparin/heparan sulphate: mechanism of epimerization of glucuronyl c-5. | in the biosynthesis of heparin and heparan sulphate, d-glucuronic acid residues are converted into l-iduronic acid (idoa) units by c-5 epimerization, at the polymer level. the reaction catalysed by the epimerase occurs by reversible abstraction and readdition of a proton at c-5 of target hexuronic acid residues, through a carbanion intermediate, with or without an inversion of configuration at c-5 [prihar, campbell, feingold, jacobsson, jensen, lindahl and rodén (1980) biochemistry 19, 495-500]. ... | 2000 | 10727403 |
| high-throughput assay for inorganic pyrophosphatases using the cytosolic enzymes of saccharomyces cerevisiae and human as an example. | this paper describes the development of a new, malachite green based, enzymatic assay for the identification of specific inhibitors of inorganic pyrophosphatase (ippase) from saccharomyces cerevisiae for antifungal drug discovery. the human ippase was used as counterscreen. the coding regions of both enzymes were amplified, cloned into a vector providing a his-tag at the c-terminus, expressed in escherichia coli, and purified by metal chelate affinity chromatography. since the complete human seq ... | 2000 | 10733883 |
| the effects of preslaughter washing on the reduction of escherichia coli o157:h7 transfer from cattle hides to carcasses during slaughter. | fresh bovine faeces were inoculated with a non-toxigenic, antibiotic resistant strain of escherichia coli o157:h7, spread on the rump areas of 30 heifers and allowed to dry for 24 h. ten of the cattle then entered the normal slaughter process without further treatment. the remaining cattle were washed with a powerhose for 1 min (10 animals) and 3 min (10 animals) before entering the normal slaughter process. both washing treatments removed all visible faecal materials on the live animals althoug ... | 2000 | 10736017 |
| escherichia coli o26 detection from foods using an enrichment procedure and an immunomagnetic separation method. | we found effective enrichment procedures for detecting escherichia coli o26 in foods using methods that are used for e. coli o157. ground beef or radish sprouts inoculated with approximately 6 colony-forming units of e. coli o26 were homogenized in 225 ml of various broths. after static incubation at 37 degrees c or 42 degrees c for 6 h or 18 h, we isolated the inoculated bacterium by plating onto rainbow agar o157 with novobiocin. in combination with the immunomagnetic separation method, e. col ... | 2000 | 10736019 |
| inhibitory effects of bovine lactoferrin on the adherence of enterotoxigenic escherichia coli to host cells. | adherence is an essential and prerequisite step for the colonization of mucosal surfaces by enterotoxigenic escherichia coli (etec). we studied the effect of bovine lactoferrin (blf) on the adherence of etec to human epithelial cells in vitro, and to intestinal mucosa of icr germfree mice in vivo. in the in vitro study, blf was found to inhibit the adherence of etec. this adhesion-inhibiting activity of blf was found to lessen with decreasing blf concentration, but the data obtained suggest a po ... | 2000 | 10737192 |
| epidemiological study of pap genes among diarrheagenic or septicemic escherichia coli strains producing cs31a and f17 adhesins and characterization of pap(31a) fimbriae. | the association of the pap operon with the cs31a and f17 adhesins was studied with 255 escherichia coli strains isolated from calves, lambs, or humans with diarrhea. the three classes of papg adhesin with different receptor binding preferences were also screened. the pap operon was associated with 50 and 36% of human strains that produced cs31a and ovine strains that produced f17, respectively. among the bovine isolates, the pap operon was detected in 61% of the cs31a-positive isolates and 72% o ... | 2000 | 10747134 |
| activity of hydrolysed lactoferrin against foodborne pathogenic bacteria in growth media: the effect of edta. | lactoferrin was hydrolysed with pepsin and the antimicrobial activity of the resulting hydrolysate (hlf) was studied in 1% peptone, 0.05% yeast extract, 1% glucose (pyg) medium and tryptic soy broth (tsb). hlf was effective against listeria monocytogenes, enterohaemorrhagic escherichia coli and salmonella enteritidis in pyg, however, the highest studied concentration (1.6 mg ml-1) did not inhibit growth of any of these organisms in tsb. the addition of edta enhanced the activity of hlf in tsb, i ... | 2000 | 10747257 |
| a quantitative approach to classifying holstein cows based on antibody responsiveness and its relationship to peripartum mastitis occurrence. | a quantitative approach was developed to classify holstein cows and heifers based on phenotypic variation of serum antibody response and to determine associations with peripartum mastitis. using an index, 136 cows and heifers were classified into high (group 1), average (group 2), or low (group 3) antibody groups following immunization with ovalbumin at wk -8, -3, and 0 relative to parturition. the ranking of groups based on the quantitative index of serum antibody response to ovalbumin were sim ... | 2000 | 10750107 |
| phosphoaminoglycosides inhibit swi2/snf2 family dna-dependent molecular motor domains. | members of the swi2/snf2 family of proteins participate in an array of nucleic acid metabolic functions, including chromatin remodeling and transcription. the present studies identify a novel strategy to specifically inhibit the functional dna-dependent adenosinetriphosphatase (atpase) motor domain common to swi2/snf2 family members. we have identified preparations of phosphoaminoglycosides, which are natural products of aminoglycoside-resistant bacteria, as inhibitors of the in vitro activities ... | 2000 | 10757984 |
| typing of intimin genes in human and animal enterohemorrhagic and enteropathogenic escherichia coli: characterization of a new intimin variant. | enteropathogenic escherichia coli (epec) and enterohemorrhagic e. coli (ehec) produce the characteristic "attaching and effacing" (a/e) lesion of the brush border. intimin, an outer membrane protein encoded by eae, is responsible for the tight association of both pathogens with the host cell. several eae have been cloned from different epec and ehec strains isolated from humans and animals. these sequences are conserved in the n-terminal region but highly variable in the last c-terminal 280 amin ... | 2000 | 10603369 |
| the influence of inorganic phosphate on the activity of adenosine kinase. | the enzyme adenosine kinase (ak; ec 2.7.1.20) shows a dependence upon inorganic phosphate (pi) for activity. the degree of dependence varies among enzyme sources and the ph at which the activity is measured. at physiological ph, recombinant ak from chinese hamster ovary (cho) cells and ak from beef liver (bl) show higher affinities for the substrate adenosine (ado), larger maximum velocities and lower sensitivities to substrate inhibition in the presence of pi. at ph 6.2, both bl and cho ak exhi ... | 2000 | 10606765 |
| prevalence of escherichia coli o157:h7 from cull dairy cows in new york state and comparison of culture methods used during preharvest food safety investigations. | a number of protocols for the cultural detection of escherichia coli o157:h7 in clinical fecal specimens have been proposed. in the present study direct plating of cattle feces was compared to three different broth enrichment protocols, i.e., a protocol with modified e. coli broth with novobiocin, a protocol with trypticase soy broth with cefixime and vancomycin, and a protocol with gram-negative broth with novobiocin, for their relative abilities to detect e. coli o157:h7 in feces. in all enric ... | 2000 | 10618108 |
| effect of ph on survival, thermotolerance, and verotoxin production of escherichia coli o157:h7 during simulated fermentation and storage. | heat treatment is increasingly being introduced to fermented meat processing, since the acid tolerance properties of escherichia coli o157:h7 can permit this organism to survive traditional processing procedures. this study investigated the effect of growth ph and fermentation on the thermotolerance at 55 degrees c of e. coli o157:h7 in a model fermented meat system. e. coli o157:h7 (strain 380-94) was grown at ph 5.6 or 7.4 (18 h at 37 degrees c), fermented to ph 4.8 or 4.4 in brain heart infus ... | 2000 | 10643763 |
| interventions to reduce microbiological contamination of beef variety meats. | hot water and solutions of acetic acid, lactic acid, or trisodium phosphate applied by immersion or spraying, chlorine solution applied by immersion, and exposure to steam in a pasteurization system, in a cabinet, or in combination with vacuum were evaluated for their effectiveness in reducing levels of bacterial contamination on samples of beef cheek meat, large intestine, lips, liver, oxtail, and tongue. treated samples (five per treatment) and controls were analyzed for aerobic plate counts ( ... | 2000 | 10643768 |
| comparison of membrane filtration rates and hydrophobic grid membrane filter coliform and escherichia coli counts in food suspensions using paddle-type and pulsifier sample preparation procedures. | food suspensions prepared by pulsifier contained less debris and filtered 1.3x to 12x faster through hydrophobic grid membrane filters (hgmfs) than those prepared by stomacher 400. coliform and escherichia coli counts made by an hgmf method yielded 84 and 36 paired samples, respectively, positive by both suspending methods. overall counts of pulsificates and stomachates did not differ significantly for either analysis, though coliform counts by pulsifier were significantly higher in mushrooms an ... | 2000 | 10643783 |
| inhibition of protein phosphatase-1 by clavosines a and b. novel members of the calyculin family of toxins. | site-directed mutagenesis was used to investigate the mechanism of interaction between the catalytic subunit of human protein phosphatase-1 (pp-1cgamma) and members of the calyculin family of toxins. clavosines a and b are related to calyculins but are glycosylated with a trimethoxy rhamnose group. we provide experimental evidence implicating tyr-134 as an important residue in pp-1cgamma that mediates interactions with the calyculins. mutation of tyr-134 to phe, to prevent hydrogen bond formatio ... | 2000 | 10660582 |
| virulence genotypes and serotypes of verotoxigenic escherichia coli isolated from cattle and foods in argentina. importance in public health. | virulence factors of verotoxin-producing escherichia coli (vtec) strains isolated from hamburgers and ground beef were studied in argentina by pcr. their virulence profiles were correlated with those corresponding to strains isolated from calves and adult cattle. most virulent profiles (vts+ eae+ mp+) were present in e. coli from healthy and diarrheic calves corresponding to o5:h-, o5:h27, o20:h?, o26:h11, o38:h?, o103:h-, o103:h2, o111:h-, o118:h16, o165:h-serotypes. the presence of the eae gen ... | 2000 | 11142505 |
| [epidemiology, pathogenesis, treatment and prevention of bovine acute escherichia coli mastitis, a literature review]. | comparisons of the rate of incidence of clinical mastitis caused by e. coli during the last 40 years demonstrate the increasing significance of this disease for modern milk production. because of the acute nature of this disease it was not possible until now to establish by documentary evidence a spontaneous case from the beginning on--and thereby to give certain evidence to the pathogenesis. nevertheless a multitude of reports about experimentally caused mastitis or observations of solitary asp ... | 2000 | 11153230 |
| effects of subinhibitory concentrations of ciprofloxacin on enterotoxigenic escherichia coli virulence factors. | eight enterotoxigenic escherichia coli were studied with the aim of investigating the effect of subinhibitory concentrations of ciprofloxacin on their adherence properties and on the expression of thermolabile enterotoxin. our data showed that the hydrophobicity on the bacterial cell surface, the hemagglutination properties, and thermolabile enterotoxin production were considerably reduced after treatment with subinhibitory concentrations of ciprofloxacin, suggesting that ciprofloxacin may be ca ... | 2000 | 11154030 |
| the escherichia coli pii signal transduction protein regulates the activities of the two-component system transmitter protein nrii by direct interaction with the kinase domain of the transmitter module. | the pii signal transduction protein regulates the transcription of nitrogen-regulated genes by controlling the kinase and phosphatase activities of nrii. we used a cross-linking approach to study the interaction of the t-loop of the pii protein with nrii. cross-linking of pii to nrii required atp and 2-ketoglutarate, allosteric effectors known to control pii activity, and was not affected by the presence of excess nonspecific proteins such as bovine serum albumin. the purified cross-linked speci ... | 2000 | 11063581 |
| host defense function in neutrophils from the american bison (bison bison). | selected host defense functions of neutrophils isolated from american bison (bison bison) were characterized and compared with those of cattle (bos taurus). bison neutrophils had a robust chemotactic response to both il-8 and ltb(4), with maximal responses occurring at 10(-7) m (il-8) and 10(-8) m (ltb(4)). the magnitude of the chemotactic response to il-8 was similar in bison and bovine neutrophils (except at 10(-7) m il-8, where bison had a stronger response). in response to ltb(4), bison neut ... | 2000 | 11064290 |
| survival of escherichia coli o157 in faeces of experimentally infected rats and domestic pigeons. | in order to evaluate the role of some synanthropic animals in the spreading of escherichia coli o157, laboratory rats and domestic pigeons were experimentally infected per os with e. coli o157. rats infected with 10(5) colony forming units (cfu) (n = 5) and 10(9) cfu (n = 5) shed e. coli o157 for 2 +/- 1.7 d and 9.8 +/- 1.3 d, respectively. in the faeces of infected rats stored at 4 degrees c in a moist environment, at 4 degrees c in a dry environment or at 20 degrees c in a moist environment, e ... | 2000 | 11069635 |
| in situ hybridization method for studies of cell wall deficient m. paratuberculosis in tissue samples. | cell wall deficient forms of mycobacteria may be important in the pathogenesis of crohn's disease and sarcoidosis. however, no method has been available to localize this type of organisms in tissue sections. we developed an in situ hybridization method for the demonstration of mycobacterium paratuberculosis spheroplasts (cell wall deficient forms) in paraffin embedded tissue sections.m. paratuberculosis spheroplasts were prepared by treatment with glycine and lysozyme. pieces of beef were inject ... | 2000 | 11118736 |
| tumor necrosis factor-alpha and nitrite/nitrate responses during acute mastitis induced by escherichia coli infection and endotoxin in dairy cows. | concentrations of tumor necrosis factor-alpha (tnf-alpha) and of no(x) (sum of nitrite and nitrate as indicators of endogenous nitric oxide production) in milk and blood plasma were measured in three mastitis models in dairy cows in early lactation. escherichia coli p4:o37 bacteria or endotoxin o111:b4 were administered into both left quarters of 12 and 6 cows, respectively. six of the e. coli-infected cows were treated with a bactericidal antibiotic (enrofloxacin; bayer ag, leverkusen, germany) ... | 2000 | 11118787 |
| multiple restraints to the unfolding of spermidine nucleoids from escherichia coli. | bacterial dna is largely localized in compact bodies known as nucleoids. the structure of the bacterial nucleoid and the forces that maintain its dna in a highly compact yet accessible form are largely unknown. in the present study, we used urea to cause controlled unfolding of spermidine nucleoids isolated from escherichia coli to determine factors that are involved in nucleoid compaction. isolated nucleoids unfolded at approximately 3.2 m urea. addition of pancreatic rnase reduced the urea con ... | 2000 | 11121306 |
| identification of escherichia coli recovered from milk of sows with coliform mastitis by random amplified polymorphic dna (rapd) using standardized reagents. | a standardized-reagents commercial kit for random amplified polymorphic dna (rapd) analysis was used for typing 58 escherichia coli strains that were recovered from the milk of sows, having coliform mastitis, within a single swineherd in sweden. previously, the 58 e. coli strains were characterized serologically and profiled biochemically. they were also evaluated for their serum resistance and their ability to adhere to fibronectin and bovine fetal fibroblasts. the rapd analysis was fast, easil ... | 2000 | 11126575 |
| relationship between intra-uterine bacterial contamination, endotoxin levels and the development of endometritis in postpartum cows with dystocia or retained placenta. | a study was conducted to investigate the relationship between intra-uterine bacterial contamination, endotoxin levels and the development of endometritis in cows that experienced a dystocia or retained their placenta. fifteen healthy cows, 31 cows with retained placenta (rp) and 13 cows that had dystocia were clinically examined 1 or 2 days after parturition when a uterine swab for bacteriological examination was taken. in addition, plasma and uterine lochia samples were collected to determine l ... | 2000 | 11131320 |
| effects of diet on rumen proliferation and fecal shedding of escherichia coil o157:h7 in calves. | calves inoculated with escherichia coli o157:h7 and fed either a high-roughage or high-concentrate diet were evaluated for rumen proliferation and fecal shedding of e. coli o157:h7. calves fed the high-roughage diet had lower mean rumen volatile fatty acid concentrations and higher rumen ph values than did calves fed the high-concentrate diet. despite these differences in rumen conditions, the calves fed the high-roughage diet did not have greater rumen populations of e. coli o157: h7 and did no ... | 2000 | 11131882 |
| validation of acid washes as critical control points in hazard analysis and critical control point systems. | a 2% lactic acid wash used in a large meat-processing facility was validated as an effective critical control point (ccp) in a hazard analysis and critical control point (haccp) plan. we examined the microbial profiles of beef carcasses before the acid wash, beef carcasses immediately after the acid wash, beef carcasses 24 h after the acid wash, beef subprimal cuts from the acid-washed carcasses, and on ground beef made from acid-washed carcasses. total mesophilic, psychrotrophic, coliforms, gen ... | 2000 | 11131890 |
| milk leucocyte population patterns in bovine udder infection of different aetiology. | this study compared the different leucocyte populations in milk from udders infected with different mastitic pathogens and in different stages of infection. milk samples were collected from quarters free of intramammary infection, acutely infected with escherichia coli or staphylococcus aureus and chronically infected with s. aureus, coagulase-negative staphylococci (cns) or streptococcus dysgalactiae. udder bacteriological status was confirmed after three consecutive bacteriological examination ... | 2000 | 11075546 |
| antitumor interaction of short-course endostatin and ionizing radiation. | the purpose of this study was to evaluate whether endostatin, an antiangiogenic cleavage fragment of collagen xviii, enhances the antitumor effects of ionizing radiation (ir). endostatin was injected to coincide with fractionated radiotherapy. | 2000 | 11079167 |
| the effect of different grain diets on fecal shedding of escherichia coli o157:h7 by steers. | three groups of six yearling steers (three rumen fistulated plus three nonfistulated) fed one of three different grain diets (85% cracked corn, 15% whole cottonseed and 70% barley, or 85% barley) were inoculated with 10(10) cfu of escherichia coli o157:h7 strain 3081, and the presence of the inoculated strain was followed in the rumen fluid and feces for a 10-week period. e. coli o157:h7 was rapidly eliminated from the rumen of the animals on all three diets but persisted in the feces of some an ... | 2000 | 11079685 |
| molecular cloning of nadph-cytochrome p450 oxidoreductase from silkworm eggs. its involvement in 20-hydroxyecdysone biosynthesis during embryonic development. | using rt-pcr, a cdna fragment of nadph-cytochrome p450 oxidoreductase from silkworm, bombyx mori, was cloned from three-day-old nondiapause eggs. race was used to isolate the ends of the dna. the full-length cdna obtained was composed of 3471 bp with an open reading frame encoding a protein of 687 amino-acid residues with a relative molecular mass of 77 700. the protein, fused with glutathione s-transferase, was expressed in escherichia coli and purified to homogeneity. the fused protein not onl ... | 2000 | 11082204 |
| a functional water channel protein in the pathogenic bacterium brucella abortus. | the gene for a new bacterial aquaporin, aqpx, was cloned from the pathogenic gram-negative bacterium brucella abortus. the gene was mapped on the large chromosome of b. abortus. it is flanked by one upstream and two downstream copies of the brucella repeated sequence bru-rs. prediction from the nucleotide sequence indicated that the protein is a member of the mip family, which comprises channels for water and/or solute transport. expression in xenopus oocytes and cryoelectron microscopy of esche ... | 2000 | 11101683 |
| dimer formation by a "monomeric" protein. | dimeric proteins can arise by the swapping of structural domains between monomers. the prevalence of this occurrence is unknown. ribonuclease a (rnase a) is assumed to be a monomer near physiological conditions. here, this hypothesis is tested and found to be imprecise. the two histidine residues (his12 and his119) in the active site of rnase a arise from two domains (s-peptide and s-protein) of the protein. the h12a and h119a variants have 10(5)-fold less ribonucleolytic activity than does the ... | 2000 | 11106177 |
| results of a longitudinal study of the prevalence of escherichia coli o157:h7 on cow-calf farms. | to describe the frequency and distribution of escherichia coli o157:h7 in the feces and environment of cow-calf herds housed on pasture. | 2000 | 11108182 |
| ca(2+)-binding proteins in the retina: from discovery to etiology of human disease(1). | examination of the role of ca(2+)-binding proteins (cabps) in mammalian retinal neurons has yielded new insights into the function of these proteins in normal and pathological states. in the last 8 years, studies on guanylate cyclase (gc) regulation by three gc-activating proteins (gcap1-3) led to several breakthroughs, among them the recent biochemical analysis of gcap1(y99) mutants associated with autosomal dominant cone dystrophy. perturbation of ca(2+) homeostasis controlled by mutant gcap1 ... | 2000 | 11108966 |
| coenzyme q is an obligatory cofactor for uncoupling protein function. | uncoupling proteins (ucps) are thought to be intricately controlled uncouplers that are responsible for the futile dissipation of mitochondrial chemiosmotic gradients, producing heat rather than atp. they occur in many animal and plant cells and form a subfamily of the mitochondrial carrier family. physiological uncoupling of oxidative phosphorylation must be strongly regulated to avoid deterioration of the energy supply and cell death, which is caused by toxic uncouplers. however, an h+ transpo ... | 2000 | 11117751 |
| formation and characterization of a single trp-trp cross-link in indolicidin that confers protease stability without altering antimicrobial activity. | indolicidin is a 13-residue cationic, antimicrobial peptide-amide isolated from the cytoplasmic granules of bovine neutrophils. the unique composition of indolicidin distinguishes it from alpha-helical and beta-structured cationic peptides, because five of indolicidin's 13 residues are tryptophans: h-ile-leu-pro-trp-lys-trp-pro-trp-trp-pro-trp-arg-arg-nh(2). solid phase synthesis of indolicidin gave rise to a minor byproduct that possessed unusual fluorescence and uv absorbance properties compar ... | 2000 | 10766833 |
| rapid and specific enzyme immunoassay on hydrophobic grid membrane filter for detection and enumeration of thermophilic campylobacter spp. from milk and chicken rinses. | six commercially available anti-campylobacter antibodies were examined for their applicability in an enzyme immunoassay on hydrophobic grid membrane filters, both for the detection and enumeration of campylobacter spp. when a panel of nine campylobacter (seven campylobacter jejuni and two campylobacter coli) and eight non-campylobacter strains were used in a dot-blot format enzyme immunoassay to test the specificity of these antibodies, only one polyclonal antibody (biodesign) detected all campy ... | 2000 | 10772214 |
| purification, cloning, expression, and mechanism of action of a novel platelet aggregation inhibitor from the salivary gland of the blood-sucking bug, rhodnius prolixus. | rhodnius prolixus aggregation inhibitor 1 (rpai-1), a 19-kda protein isolated from the salivary gland of r. prolixus, was purified by strong cation exchange and reverse-phase high performance liquid chromatographies. based on 49 amino-terminal amino acid sequences of rpai-1, primers were produced to generate probes to screen an r. prolixus salivary gland cdna library. a phage containing the full-length clone of rpai-1 codes for a mature protein of 155 amino acids. rpai-1 shows sequence homology ... | 2000 | 10777556 |
| identification of the f17 fimbrial subunit- and adhesin-encoding (f17a and f17g) gene variants in necrotoxigenic escherichia coli from cattle, pigs and humans. | putative colonization factors of the f17 family of fimbrial adhesins have been identified in necrotoxigenic escherichia coli type 1 and type 2 (ntec1 and ntec2) from calves, pigs, and humans. the f17a and f17g gene variants, coding respectively for the major subunit and for the adhesin of the f17 fimbriae, were typed in 70 e. coli carrying f17-related sequences (15 ntec1, 51 ntec2, and four non-ntec) by colony hybridisation with gene probes derived from the different f17a gene variants (a, b, c, ... | 2000 | 10781731 |
| enzyme-mediated sulfide production for the reconstitution of [2fe-2s] clusters into apo-biotin synthase of escherichia coli. sulfide transfer from cysteine to biotin. | we previously showed that biotin synthase in which the (fe-s) cluster was labelled with 34s by reconstitution donates 34s to biotin [b. tse sum bui, d. florentin, f. fournier, o. ploux, a. méjean & a. marquet (1998) febs lett. 440, 226-230]. we therefore proposed that the source of sulfur was very likely the (fe-s) centre. this depletion of sulfur from the cluster during enzymatic reaction could explain the absence of turnover of the enzyme which means that to restore a catalytic activity, the c ... | 2000 | 10785391 |
| specificity determinants for the pyruvate dehydrogenase component reaction mapped with mutated and prosthetic group modified lipoyl domains. | efficient catalysis in the second step of the pyruvate dehydrogenase (e1) component reaction requires a lipoyl group to be attached to a lipoyl domain that displays appropriately positioned specificity residues. as substrates, the human dihydrolipoyl acetyltransferase provides an n-terminal (l1) and an inner (l2) lipoyl domain. we evaluated the specificity requirements for the e1 reaction with 27 mutant l2 (including four substitutions for the lipoylated lysine, lys(173)), with three analogs sub ... | 2000 | 10788482 |
| invited review: effects of diet shifts on escherichia coli in cattle. | escherichia coli o157:h7 is a pathogenic bacterium that causes acute illness in humans, but mature cattle are not affected. e. coli o157:h7 can enter the human food supply from cattle via fecal contamination of beef carcasses at slaughter. previous attempts to correlate the incidence of e. coli o157:h7 with specific diets or feeding management practices gave few statistically significant or consistent findings. however, recent work indicates that cattle diets may be changed to decrease fermentat ... | 2000 | 10791804 |
| use of 8-hydroxyquinoline-beta-d-glucuronide for presumptive identification of shiga toxin-producing escherichia coli o157. | 8-hydroxyquinoline-beta-d-glucuronide (hqg) was used to improve the presumptive identification of shiga toxin-producing escherichia coli o157 (stec o157) on sorbitol macconkey agars (smac). advantages of hqg are (i) that it is less expensive than 5-bromo-4-chloro-3-indoxyl-glucuronide; (ii) that it is visible in normal daylight and (iii) that it does not diffuse into the agar like 4-methylumbelliferryl-beta-d-glucuronide (mug). sixteen stec o157 isolates, 91 bovine mastitis-associated e. coli is ... | 2000 | 10792673 |
| isolation, characterization and expression of a gra2 homologue from neospora caninum. | a cdna library derived from mrna of tachyzoites of neospora caninum (nc-liverpool strain) was screened with antisera from a cow naturally infected with n. caninum. the dna sequence of 1 recombinant isolated predicted a significant protein sequence homology of the gene product to the 28 kda (gra2) antigen of toxoplasma gondii. studies on the n. caninum gene coding for this antigen demonstrated the presence of a single intron flanked by 2 exons; the gene was also highly expressed in culture-derive ... | 2000 | 10811279 |
| a one year study of escherichia coli o157 in raw beef and lamb products. | between april 1996 and march 1997 we examined 5093 samples of raw beef and lamb products for the presence of e. coli o157. samples were purchased from 81 small butchers' shops in south yorkshire. in march 1997 we also examined five samples of dried mint for the presence of e. coli o157. strains of e. coli o157 were isolated by enrichment culture in modified buffered peptone water followed by immunomagnetic separation and culture of magnetic beads onto cefixime tellurite sorbitol macconkey agar. ... | 2000 | 10813144 |
| brucella abortus strain rb51 as a vector for heterologous protein expression and induction of specific th1 type immune responses. | brucella abortus strain rb51 is a stable, rough, attenuated mutant widely used as a live vaccine for bovine brucellosis. our ultimate goal is to develop strain rb51 as a preferential vector for the delivery of protective antigens of other intracellular pathogens to which the induction of a strong th1 type of immune response is needed for effective protection. as a first step in that direction, we studied the expression of a foreign reporter protein, beta-galactosidase of escherichia coli, and th ... | 2000 | 10816476 |
| replacement of histidine 340 with alanine inactivates the group a streptococcus extracellular cysteine protease virulence factor. | streptococcus pyogenes expresses a highly conserved extracellular cysteine protease that is a virulence factor for invasive disease, including soft tissue infection. site-directed mutagenesis was used to generate a his340ala recombinant mutant protein that was made as a stable 40-kda zymogen by escherichia coli. purified his340ala protein was proteolytically inactive when bovine casein and human fibronectin were used as substrates. wild-type 28-kda streptococcal protease purified from s. pyogene ... | 2000 | 10816533 |
| antimicrobial effect of herb extracts against escherichia coli o157:h7, listeria monocytogenes, and salmonella typhimurium associated with beef. | the effects of plant extracts against pathogenic bacteria in vitro are well known, yet few studies have addressed the effects of these compounds against pathogens associated with muscle foods. a series of experiments was conducted to determine the effectiveness of a commercially available, generally recognized as safe, herb extract dispersed in sodium citrate (protecta one) or sodium chloride (protecta two) against escherichia coli o157:h7, salmonella typhimurium, and listeria monocytogenes asso ... | 2000 | 10826716 |
| resonance raman studies of oxo intermediates in the reaction of pulsed cytochrome bo with hydrogen peroxide. | cytochrome bo from escherichia coli, a member of the heme-copper terminal oxidase superfamily, physiologically catalyzes reduction of o(2) by quinols and simultaneously translocates protons across the cytoplasmic membrane. the reaction of its ferric pulsed form with hydrogen peroxide was investigated with steady-state resonance raman spectroscopy using a homemade microcirculating system. three oxygen-isotope-sensitive raman bands were observed at 805/x, 783/753, and (767)/730 cm(-)(1) for interm ... | 2000 | 10828985 |
| molten globule structure of equine beta-lactoglobulin probed by hydrogen exchange. | the molten globule structure of equine beta-lactoglobulin has been inferred from the hydrogen exchange protection of the backbone amide protons. in order to make it possible to measure the hydrogen exchange kinetics of the individual backbone amide protons, the uniformly (15)n-labeled recombinant protein was expressed in escherichia coli and the nmr peak assignment was obtained for most of the backbone protons. the chemical shift and noe results obtained under the condition where the protein ass ... | 2000 | 10835282 |
| induction of parturition with prostaglandin f2 alpha as a possible model to study impaired reproductive performance in the dairy cow. | parturitions were induced in five cows, 2 weeks before term using prostaglandin (pg) f(2alpha). two i.m. injections were performed with an interval of 24 h. all cows calved within 5 days (average 2.7 days) after the first injection of pgf(2alpha). out of five cows, four had retained fetal membranes (rfm). each animal was sampled for bacteriological examination using uterine biopsies twice a week during 42 days postpartum (pp). jugular vein blood samples were withdrawn for pgf(2alpha)-metabolite ... | 2000 | 10837974 |
| expression of yeast inm1 encoding inositol monophosphatase is regulated by inositol, carbon source and growth stage and is decreased by lithium and valproate. | inositol monophosphatase plays a vital role in the de novo biosynthesis of inositol and in the phosphoinositide second messenger signalling pathway. we cloned the saccharomyces cerevisiae open reading frame (orf) yhr046c (termed inm1), which encodes inositol monophosphatase, characterized the protein inm1p and analysed expression of the inm1 gene. inm1 was expressed in bacteria under the control of the lacz promoter. the purified protein has inositol monophosphatase activity that is inhibited by ... | 2000 | 10844654 |
| rotavirus and concurrent infections with other enteropathogens in neonatal diarrheic dairy calves in spain. | faeces samples from 218, one to 30 days old, diarrheic dairy calves in 65 dairy herds were screened for the presence of rotavirus and concurrent infections with coronavirus, cryptosporidium, f5+ escherichia coli and salmonella spp. calves were grouped according to their age as follows: 1-7, 8-14, 15-21 and 22-30 days. rotavirus infection was detected in 46.9%, 45.6%, 33.8% and 48.3% of the calves in the respective age-groups. no significant differences in the detection rate of rotavirus were fou ... | 2000 | 10855663 |
| high levels of background flora inhibits growth of escherichia coli o157:h7 in ground beef. | the influence of natural background flora under aerobic and anaerobic incubation on the growth of escherichia coli o157:h7 in ground beef was investigated. the background flora from eight different commercial ground beef were added to ground beef spiked with e. coli o157:h7 and stored either aerobically or anaerobically at 12 degrees c. the results showed that the presence of a large number of background bacteria in the ground meat inhibited the growth of e. coli o157:h7 both aerobically and ana ... | 2000 | 10857548 |
| molecular cloning and expression of cu/zn-containing superoxide dismutase from fasciola hepatica. | the cytosolic superoxide dismutase (sod) of fasciola hepatica, a causative agent of fascioliasis, was purified and characterized. the enzyme consists of two identical subunits, each with an apparent molecular mass of 17.5 kda. an analysis of the enzyme's primary structure and inhibition studies revealed that the enzyme is a copper/zinc-containing sod (cu/zn-sod). the enzyme activity was relatively stable in a broad ph range, from ph 7.0 to 10.0, and the enzyme showed maximum activity at ph 7.5. ... | 2000 | 10858207 |
| the genetic diversity of predominant escherichia coli strains isolated from cattle fed various amounts of hay and grain(1). | when the 16s rdna of predominant escherichia coli strains from cattle was digested with hhai and haeiii, the strains could be sub-divided into four operational taxonomic units. when genomic dna was digested with xbai, strains could be grouped into 24 pulsed-field gel electrophoresis genotypes (>95% dice similarity) and five clades (>20% dice similarity). diet (hay versus grain) and gastrointestinal compartment (rumen versus colon) did not have a large impact on diversity. however, both analyses ... | 2000 | 10858581 |
| role of non-o157 vtec. | non-o157 vtec are typical escherichia coli that differ only in their ability to produce verocytotoxins (vt). the transmission of vtec is discussed in relation to the transmission of commensal e. coli. the emergence over the last few decades of a great variety of vtec serotypes from healthy and diseased humans and animals is described. particular attention is given to the distribution of the more important serogroups pathogenic for humans that have been described from around the world, particular ... | 2000 | 10880178 |