Publications

production of recombinant buffalo (bubalus bubalis) and goat (capra hircus) growth hormones from genetically modified e. coli strains.	the growth hormone cdnas of indian reverine buffalo (bubalus bubalis) and beetal goat (capra hircus) were cloned in escherichia coli through rt-pcr technique. nucleotide sequencing revealed several silent mutations in both cdnas and only one amino acid change in the case of goat when compared to reported bovine (bos taurus) sequence. the high level expression of both the polypeptide hormones was achieved in e. coli (> or =30% of soluble intracellular proteins) through the construction of two-cis ...	2002	12084476
the effect of pathogen-specific clinical mastitis on the lactation curve for somatic cell count.	data from 274 dutch herds recording clinical mastitis (cm) over an 18-mo period were used to investigate the effect of pathogen-specific cm on the lactation curve for somatic cell count (scc). analyzed pathogens were staphylococcus aureus, coagulase-negative staphylococci, escherichia coli, streptococcus dysgalactiae, streptococcus uberis, other streptococci, and the culture-negative samples. the dataset contained 178,754 test-day records on scc, recorded in 26,411 lactations of 21,525 cows of d ...	2002	12086069
combined use of two genetic fingerprinting methods, pulsed-field gel electrophoresis and ribotyping, for characterization of escherichia coli o157 isolates from food animals, retail meats, and cases of human disease.	two genetic fingerprinting techniques, pulsed-field gel electrophoresis (pfge) and ribotyping, were used to characterize 207 escherichia coli o157 isolates from food animals, foods of animal origin, and cases of human disease (206 of the isolates were from the united kingdom). in addition, 164 of these isolates were also phage typed. the isolates were divided into two general groups: (i) unrelated isolates not known to be epidemiologically linked (n = 154) and originating from food animals, food ...	2002	12149334
development of an antibiotic resistance monitoring system in hungary.	because of the rapid development and spread of antimicrobial resistance it is important that a system be established to monitor antimicrobial resistance in pathogenic zoonotic and commensal bacteria of animal origin. susceptibility testing of bacteria from carcasses and different samples of animal origin has been carried out in veterinary institutes for a long time but by an inconsistent methodology. the disc diffusion method proposed by the national committee for clinical laboratory standards ( ...	2002	12113174
trends in antibacterial susceptibility of mastitis pathogens during a seven-year period.	milk samples collected from dairy cattle suspected of having mastitis were submitted to the microbiology laboratory of the animal health diagnostic laboratory, michigan state university, for bacteriologic culture. a total of 2778 isolates, from the years 1994 to 2000, were isolated, identified, and subjected to in vitro antimicrobial susceptibility testing using the disk diffusion method, in accordance with national committee on clinical laboratory standards (nccls) standards. isolates included ...	2002	12086045
simple parameterization of non-proteinogenic amino acids for qsar of antibacterial peptides.	the antibacterial activity of bovine lactoferricin-(17-31)-pentadecapeptide against escherichia coli and staphylococcus aureus is sensitive to substitution of the trp residues, and synthetic peptides with phenylalanine and any of eight non-proteinogenic aromatic amino acids greatly affected antibiotic activity. using simple size-related descriptors for the new amino acids it is possible to develop quantitative structure-activity relationships (qsars) that can be used as tools in the search for m ...	2002	12148779
towards the development of selective amine oxidase inhibitors. mechanism-based inhibition of six copper containing amine oxidases.	four substrate analogs, 4-(2-naphthyloxy)-2-butyn-1-amine (1), 1,4-diamino-2-chloro-2-butene (2), 1,6-diamino-2,4-hexadiyne (3), and 2-chloro-5-phthalimidopentylamine (4) have been tested as inhibitors against mammalian, plant, bacterial, and fungal copper-containing amine oxidases: bovine plasma amine oxidase (bpao), equine plasma amine oxidase (epao), pea seedling amine oxidase (psao), arthrobacter globiformis amine oxidase (agao), escherichia coli amine oxidase (ecao), and pichia pastoris lys ...	2002	12153561
structure-activity analysis of an antimicrobial peptide derived from bovine apolipoprotein a-ii.	we previously showed that bovine apolipoprotein a-ii (apoa-ii) has antimicrobial activity against escherichia coli in pbs, and its c-terminal residues 49-76 are responsible for the activity using synthetic peptides. in order to understand the structural requirements of peptide 49-76 for the antimicrobial activity, the n- or c-terminus was truncated and then the charged (lys or asp) or ser residues were replaced by ala. deletion of the first or last three amino acids and replacement of lys-54/55 ...	2002	12097167
redox properties of the [2fe-2s] center in the 24 kda (nqo2) subunit of nadh:ubiquinone oxidoreductase (complex i).	the redox properties of the [2fe-2s] cluster in the 24 kda subunit of bovine heart mitochondrial nadh:ubiquinone oxidoreductase (complex i) and three of its homologues have been defined using protein-film voltammetry. the clusters in all four examples display characteristic, ph-dependent redox transitions, which, unusually, can be masked by high ionic strength conditions. at low ionic strength (10 mm nacl) the reduction potential varies by approximately 100 mv between high and low ph limits (ph ...	2002	12146970
membrane reconstitution of recombinant guinea pig cytochrome p45017alpha and the effects of site-directed mutagenesis on androgen formation.	although cytochrome p45017alpha catalyzes the formation of androgen from both pregnenolone and progesterone, the production of androstenedione from progesterone is a major pathway in the guinea pig, rat, mouse, and hamster. in contrast, human, bovine and sheep p45017alpha produce dehydroepiandrosterone from pregnenolone. cytochrome p45017alphas from all of these animals have high homology in the amino acid sequence around the 340-370 region. to investigate the substrate preferences for androgen ...	2002	12163137
inducible expression of an antimicrobial peptide of the innate immunity in polymorphonuclear leukocytes.	epithelia- and leukocyte-associated antimicrobial peptides provide immediate protection against microbial infections by rapidly inactivating potential pathogens. bac5 is a member of the cathelicidin family of antimicrobial peptides and is stored in the cytoplasmic granules of bovine neutrophils. we investigated the expression of this gene in airway and intestine, and although the gene was not found to be locally expressed in these tissues, a strong bac5 induction signal was detected by in situ h ...	2002	12429723
an outbreak of escherichia coli o157:h7 infections among visitors to a dairy farm.	outbreaks of escherichia coli o157:h7 infections have involved direct transmission from animals and their environment to humans. we describe an outbreak among visitors to a pennsylvania dairy and petting farm that provides public access to animals.	2002	12192014
geographic variability of escherichia coli ribotypes from animals in idaho and georgia.	several genotypic methods have been developed for determining the host origin of fecal bacteria in contaminated waters. some of these methods rely on a host origin database to identify environmental isolates. it is not well understood to what degree these host origin isolates are geographically variable (i.e., cosmopolitan or endemic). this is important because a geographically limited host origin database may or may not be universally applicable. the objective of our study was to use one genoty ...	2002	12175046
beta-lactamases in ampicillin-resistant escherichia coli isolates from foods, humans, and healthy animals.	tem-, shv-, and oxa-type beta-lactamases were studied by pcr with 124 ampicillin-resistant (amp(r)) escherichia coli isolates recovered from foods of animal origin (n = 20) and feces of humans (n = 49) and healthy animals (n = 55). pcr showed that 103 isolates were positive for tem and negative for shv and oxa. three e. coli isolates showed a positive reaction for oxa, and one showed a positive reaction for shv. the remaining 17 e. coli isolates were negative for the three enzymes by pcr. fifty- ...	2002	12234838
genetic diversity of intimin genes of attaching and effacing escherichia coli strains.	in this study, we determined the sequences of four intimin variant genes detected in attaching and effacing escherichia coli isolates of human origin. three of them were novel and were designated eae-eta (eta), eae-iota (iota), and eae-kappa (kappa). the fourth was identical to the recently described eae-zeta (zeta), isolated from a bovine e. coli o84:nm isolate. we compared these sequences with those of published intimin-alpha, intimin-beta, intimin-gamma1, intimin-gamma2, intimin- epsilon, and ...	2002	12454140
antimicrobial properties of milk: dependence on presence of xanthine oxidase and nitrite.	human and bovine milk inhibited the metabolic activity of escherichia coli, as shown by luminescence monitoring of constructs expressing the luxcdabe genes. inhibition was dependent on both xanthine oxidase (xo) activity and on the presence of nitrite, implying that xo-generated nitric oxide functions as an antibacterial agent.	2002	12234868
cdna cloning, high-level expression, purification, and characterization of an avian cu,zn superoxide dismutase from peking duck.	as a special species of avian, peking duck is often used as a model for exploring effective factors against cardio-cerebrovascular diseases, and therefore investigations of antioxidant enzymes including superoxide dismutase are intriguing. by using 3(')-race with a gene-specific primer, a cdna encoding duck cu,zn sod was amplified from the total rna extracted from peking duck liver. three free cysteine residues are found in the deduced amino acid sequence of duck sod, among which cys153 at the c ...	2002	12182817
transgenic mice harboring murine luteinizing hormone receptor promoter/beta-galactosidase fusion genes: different structural and hormonal requirements of expression in the testis, ovary, and adrenal gland.	in vivo regulation of the lh receptor (lhr) promoter was studied using transgenic (tg) mice harboring fusion genes containing three different lengths of the lhr promoter (7.4 kb, 2.1 kb, and 173 bp), fused with coding sequence of the escherichia coli beta-galactosidase (beta-gal) reporter gene. the length of the lhr promoter significantly affected the pattern of beta-gal expression. in the testis the shortest promoter directed expression primarily of the full-length beta-gal mrna, but mainly tru ...	2002	12239121
importance of glutamate 279 for the coenzyme binding of human glutamate dehydrogenase.	although the structure of glutamate dehydrogenase (gdh) has been reported from various sources including mammalian gdh, there are conflicting views regarding the location and mechanism of actions of the coenzyme binding. we have expanded these speculations by photoaffinity labeling and cassette mutagenesis. photoaffinity labeling with a specific probe, [(32)p]nicotinamide 2-azidoadenosine dinucleotide, was used to identify the nad(+) binding site within human gdh encoded by the synthetic human g ...	2002	12193607
efficacy of trimethoprim-sulfadoxine against escherichia coli in a tissue cage model in calves.	tissue cages implanted subcutaneously in calves were infected with escherichia coli. twenty-four hours later, the calves were treated either with single doses of 2.5 + 12.5 or 5 + 25 mg/kg trimethoprim (tmp) + sulfadoxine (sdx) or with five doses of 7.5 + 37.5 mg/kg tmp + sdx at 12-h intervals. in addition, one cage in each of three calves in the highest dose group was infected 3 h after initiation of treatment. untreated calves were kept as controls. concentrations of tmp and sdx in plasma and ...	2002	12485347
time-resolved step-scan fourier transform infrared spectroscopy of the co adducts of bovine cytochrome c oxidase and of cytochrome bo(3) from escherichia coli.	we have used cryogenic difference ftir and time-resolved step-scan fourier transform infrared (tr-ftir) spectroscopies to explore the redox-linked proton-pumping mechanism of heme-copper respiratory oxidases. these techniques are used to probe the structure and dynamics of the heme a(3)-cu(b) binuclear center and the coupled protein structures in response to the photodissociation of co from heme fe and its subsequent binding to and dissociation from cu(b). previous cryogenic (80 k) ftir co photo ...	2002	11851414
expression in escherichia coli, purification and kinetic characterization of human heparan sulfate 3-o-sulfotransferase-1.	heparan sulfate (hs) glycosaminoglycans are a structurally diverse class of complex biomolecules that modulate many important events at the cell surface and within the extracellular matrix and whose structural heterogeneity derives largely from the sequence-specific n- and o-sulfations catalyzed by an extensive repertoire of sulfating enzymes. we have expressed the human heparan sulfate 3-ost-1 isoform in escherichia coli and subsequently purified a soluble, active enzyme. to assess its function ...	2002	11811991
influence of puerperal uterine infection on uterine involution and postpartum ovarian activity in dairy cows.	this article presents the results of a clinical trial designed to study the effect of puerperal uterine infection on uterine involution and on ovarian activity in dairy cows, monitored twice weekly from parturition until the sixth week postpartum (wpp). infection significantly retarded uterine involution assessed by the uterine body diameter and a score of intrauterine fluid volume (iufv). by the sixth wpp, cows with normal puerperium (controls) and cows that showed mild puerperal endometritis h ...	2002	11882243
effect of apoptosis on phagocytosis, respiratory burst and cd18 adhesion receptor expression of bovine neutrophils.	polymorphonuclear neutrophil leukocytes (pmn) play an important role in intramammary defense against infections by escherichia coli. during mastitis, pmn are confronted with various inflammatory mediators that can modulate their function. in severely diseased cows, increased concentrations of lipopolysaccharide (lps) and tumor necrosis factor (tnf)-alpha (tnf-alpha) are detected in plasma. binding of lps to membrane bound cd14 molecules on monocytes cause release of inflammatory mediators such a ...	2002	11900963
[molecular epidemiological investigation of vero toxin-producing escherichia coli (vtec) isolated from diarrhea patients and dairy cattle].	to elucidate the source and route of vtec infection, we performed pulse field gel electrophoresis (pfge) an 50 isolates from human diarrhea typed as serotypes o157, o111, and o26, which were very frequently isolated from patients with vtec infection between 1986 and 1997, and 32 isolates from dairy cattle, a total of 82 isolates. the isolates were genetically analyzed based on the electrophoresis patterns of dna, and a phylogenetic tree was prepared. the isolates were classified based on similar ...	2002	11905004
in vitro expression of tumor necrosis factor-alpha, interleukin 1beta, and interleukin 8 mrna by bovine macrophages following exposure to porphyromonas levii.	the objective was to evaluate the pro-inflammatory response of bovine macrophages towards porphyromonas levii, an etiologic agent of acute interdigital phlegmon, by evaluating the mrna expression of tumor necrosis factor-alpha (tnf-alpha), interleukin 1beta (il-1beta), and interleukin 8 (il-8). bovine macrophages detect the presence of bacteria, such as p. levii, and respond by upregulating transcription of the genes for pro-inflammatory cytokines tnf-alpha and il-1beta in addition to the neutro ...	2002	11989740
engineered recombinant enteropeptidase catalytic subunit: effect of n-terminal modification.	enteropeptidase (enterokinase) is a serine protease highly specific for recognition and cleavage of the target sequence of asp-asp-asp-asp-lys (d4k). the three-dimensional structure of the enteropeptidase shows that the n-terminal amino acid is buried inside the protein providing molecular interactions necessary to maintain the conformation of the active site. to determine the influence of the n-terminal amino acid of enteropeptidase light chain (ek(l)) on the enzymatic activity, we constructed ...	2002	11913964
rapid selection of anti-hapten antibodies isolated from synthetic and semi-synthetic antibody phage display libraries expressed in escherichia coli.	antibody phage display libraries (griffin and tomlinson i) displaying antibody genes and maintained and amplified in escherichia coli were used to isolate antibodies to the hapten target microcystin lr (1000 da) conjugated to either bovine serum albumin or keyhole limpet haemocyanin. in competition enzyme-linked immunosorbent assay, bacterially expressed antibodies selected via the griffin library showed at least 300 times greater sensitivity than those isolated from the tomlinson library, for f ...	2002	12044684
shedding of escherichia coli o157:h7 in dairy cattle housed in a confined environment following waterborne inoculation.	a study of escherichia coli o157:h7 transmission and shedding was conducted with bull calves housed in individual pens within a confined environment. for comparative purposes, the numbers and duration of e. coli o157:h7 shedding in naturally infected calves were monitored after a single purchased calf (calf 156) tested positive prior to inoculation. during the next 8 days, the calves in adjacent pens and a pen directly across a walkway from calf 156 began to shed this serotype o157:h7 strain. fi ...	2002	11916717
first isolation of the enterohaemorrhagic escherichia coli o145:h- from cattle in feedlot in argentina.	enterohaemorrhagic escherichia coli (ehec) is considered to be common cause of haemorrhagic colitis (hc), thrombotic thrombocytopenic purpura and haemolytic uraemic syndrome (hus) in humans. in a previous paper, we have demonstrated that ehec are commonly found in the intestines of livestock. infections in humans are, in part, a consequence of consumption of undercooked meat or raw milk. argentina has one of the highest records of hus (300-400 cases/year; 22/100,000 children under 4 years of age ...	2002	11936956
adenoviral-mediated transfer of a lysostaphin gene into the goat mammary gland.	as a step toward preventing and curing staphylococcus aureus mastitis, an adenoviral-mediated gene transfer technique was used to enable mammary cells to synthesize and secrete lysostaphin, an anti-staphylococcal protein. a lysostaphin gene, modified for eukaryotic expression of the bioactive variant, gln125,232-lysostaphin, was inserted into a replication deficient adenovirus by homologous recombination in 293 cells. the resulting adenoviral vector containing the modified lysostaphin gene (ad-l ...	2002	12201521
antimicrobial activity of short arginine- and tryptophan-rich peptides.	highly antimicrobial active arginine- and tryptophan-rich peptides were synthesized ranging in size from 11 to five amino acid residues in order to elucidate the main structural requirement for such short antimicrobial peptides. the amino acid sequences of the peptides were based on previous studies of longer bovine and murine lactoferricin derivatives. most of the peptides showed strong inhibitory action against the gram-negative bacteria escherichia coli and pseudomonas aeruginosa, and the gra ...	2002	12212806
multiplex fluorogenic real-time pcr for detection and quantification of escherichia coli o157:h7 in dairy wastewater wetlands.	surface water and groundwater are continuously used as sources of drinking water in many metropolitan areas of the united states. the quality of water from these sources may be reduced due to increases in contaminants such as escherichia coli from urban and agricultural runoffs. in this study, a multiplex fluorogenic pcr assay was used to quantify e. coli o157:h7 in soil, manure, cow and calf feces, and dairy wastewater in an artificial wetland. primers and probes were designed to amplify and qu ...	2002	12324331
ca2+-myristoyl switch in the neuronal calcium sensor recoverin requires different functions of ca2+-binding sites.	recoverin is an ef-hand ca(2+)-binding protein that is suggested to control the activity of the g-protein-coupled receptor kinase grk-1 or rhodopsin kinase in a ca(2+)-dependent manner. it undergoes a ca(2+)-myristoyl switch when ca(2+) binds to ef-hand 2 and 3. we investigated the mechanism of this switch by the use of point mutations in ef-hand 2 (e85q) and 3 (e121q) that impair their ca(2+) binding. ef-hand 2 and 3 display different properties and serve different functions. binding of ca(2+) ...	2002	12393897
consequences of ehec colonisation in humans and cattle.	while many factors have been associated with human ehec infection, the full role these play in both human and ruminant hosts are not yet clear despite much investigation. it is hoped that the continued intense international research effort into ehec will provide further insights into the commensal versus pathogenic lifestyles of e. coli and lead to approaches to reduce ehec carriage in ruminants as well as prevent or treat human disease.	2002	12398208
[evaluation of practical usefulness of selected phenotypic and genotypic markers for pathogenicity of enterotoxic and entero-hemorrhagic strains of e.coli. ].	this study included a description of enterotoxic and verocytotoxic activity of thirty strains of e. coli and their ability to produce beta-haemolysis in a ram blood medium. enterotoxic and verocytoxic activity was determined by using rpla test. the synthesis of enterotoxin lt was observed in 10 strains and the production of e. coli shiga toxins type 1--stx1 (1 strain) or type 2 (2 strains) was observed in 3 strains of serotype o157: h7. the beta-haemolytic characteristics in vitro were demonstra ...	2002	12185692
[antimicrobial, echinococcidial and immunostimulating properties of the drug cheblin-sk-1].	the antimicrobial properties of the drug cheblin-ck-1 (cck-1) were determined in mice intraabdominally inoculated with proteus mirabilis-4691 in a dose of 140-200 million daily cultured microbial bodies. its comparison agent was ampicillin. cck-1 was found to act as an antibiotic similar to ampicillin in its effects. the antimicrobial activity of cck-1 against staphylococcus aureus and escherichia coli isolated from the contents of echinococcal cysts from patients operated on was also establishe ...	2002	12224264
resistance to quaternary ammonium compounds in food-related bacteria.	microbial resistance to antimicrobial agents continues to be a major problem. the frequent use and misuse of disinfectants based on quaternary ammonium compounds (qacs) in food-processing industries have imposed a selective pressure and may contribute to the emergence of disinfectant-resistant microorganisms. a total number of 1,325 gram-negative isolates (escherichia coli, other coliforms vibrio spp., and aeromonas spp.) and 500 enterococcus spp. from food and food-processing industries and fis ...	2002	12523638
selection of recently isolated colicinogenic escherichia coli strains inhibitory to escherichia coli o157:h7.	escherichia coli strains were screened for their ability to inhibit e. coli o157:h7. an initial evaluation of 18 strains carrying previously characterized colicins determined that only colicin e7 inhibited all of the e. coli o157:h7 strains tested. a total of 540 strains that had recently been isolated from humans and nine different animal species (cats, cattle, chickens, deer, dogs, ducks, horses, pigs, and sheep) were tested by a flip-plating technique. approximately 38% of these strains were ...	2002	12233846
flgm gains structure in living cells.	intrinsically disordered proteins such as flgm play important roles in biology, but little is known about their structure in cells. we use nmr to show that flgm gains structure inside living escherichia coli cells and under physiologically relevant conditions in vitro, i.e., in solutions containing high concentrations (>/=400 g/liter) of glucose, bsa, or ovalbumin. structure formation represents solute-induced changes in the equilibrium between the structured and disordered forms of flgm. the re ...	2002	12271132
prevalence and characterization of non-o157 shiga toxin-producing escherichia coli on carcasses in commercial beef cattle processing plants.	beef carcass sponge samples collected from july to august 1999 at four large processing plants in the united states were surveyed for the presence of non-o157 shiga toxin-producing escherichia coli (stec). twenty-eight (93%) of 30 single-source lots surveyed included at least one sample containing non-o157 stec. of 334 carcasses sampled prior to evisceration, 180 (54%) were found to harbor non-o157 stec. non-o157 stec isolates were also recovered from 27 (8%) of 326 carcasses sampled after the a ...	2002	12324330
assurance enzyme immunoassay eight hour method for detection of enterohemorrhagic escherichia coli o157:h7 in raw and cooked beef (modification of aoac official method 996.10): collaborative study.	aoac official method 996.10, assurance enzyme immunoassay (eia) for escherichia coli o157:h7 (ehec), was modified to incorporate a new enrichment protocol using biocontrol ehec8 medium for testing raw and cooked beef. foods were tested by eia and the u.s. department of agriculture/food safety and inspection service (usda/fsis) enrichment conditions and the fda bacteriological analytical manual (bam) isolation and confirmation techniques. a total of 14 collaborators participated. raw and cooked g ...	2002	12374401
recognition by tryptophanyl-trna synthetases of discriminator base on trnatrp from three biological domains.	to study the recognition by tryptophanyl-trna synthetase (trprs) of trna(trp) discriminator base, mutations were introduced into the discriminator base of bacillus subtilis, archeoglobus fulgidus, and bovine trna(trp), representing the three biological domains. when b. subtilis, a. fulgidus, and human trprs were used to acylate these trna(trp), two distinct preference profiles regarding the discriminator base of different trna(trp) substrates were found: g>a>u>c for b. subtilis trprs, and a>c>u> ...	2002	11834741
apoptosis of bovine neutrophils during mastitis experimentally induced with escherichia coli or endotoxin.	to determine whether apoptosis of neutrophils was accelerated during mastits experimentally induced by use of escherichia coli or e coli endotoxin and whether differences were apparent in the response to e coli or endotoxin.	2002	11911583
prevalence and genetic profiling of virulence determinants of non-o157 shiga toxin-producing escherichia coli isolated from cattle, beef, and humans, calcutta, india.	we investigated the prevalence of shiga toxin-producing escherichia coli (stec) in hospitalized diarrhea patients in calcutta, india, as well as in healthy domestic cattle and raw beef samples collected from the city's abattoir. multiplex polymerase chain reaction using primers specific for stx1 and stx2 detected stec in 18% of cow stool samples, 50% of raw beef samples, and 1.4% and 0.6% of bloody and watery stool samples, respectively, from hospitalized diarrhea patients. various virulence gen ...	2002	11749749
molecular analysis of chromosomally florfenicol-resistant escherichia coli isolates from france and germany.	the aim of this study was to analyse chromosomally florfenicol-resistant escherichia coli isolates for their genetic relatedness, and also for the presence of the flor gene and its adjacent regions, in order to compare these regions with those associated with a flor gene located on a conjugative plasmid from e. coli. twenty-two bovine e. coli from france and germany were examined. florfenicol resistance was determined by mic determination. the presence of the flor gene was confirmed by hybridiza ...	2002	11751766
evaluation of an antimicrobial-impregnated continuous ambulatory peritoneal dialysis catheter for infection control in rats.	infection is the most serious complication arising in long-term continuous ambulatory peritoneal dialysis (capd), specifically peritonitis and exit-site infection. the initial weeks after implantation is the crucial period during which bacterial colonization of the catheter results in maximal morbidity, with staphylococcus aureus being the most virulent organism. we developed an antimicrobial-impregnated capd catheter by impregnating the cuff and tubing with chlorhexidine, silver sulfadiazine, a ...	2002	11774116
molecular typing techniques to characterize the development of a lactic acid bacteria community on vacuum-packaged beef.	the development of a community of lactic acid bacteria from vacuum-packaged beef was investigated during a 6-week storage trial at 2 degrees c. the lactic acid bacteria population was monitored by using molecular techniques to identify a random sample of isolates at biweekly intervals during the storage trial. the polymerase chain reaction and a randomly amplified polymorphic dna technique were used to identify and distinguish populations of lactic acid bacteria that developed during the storage ...	2002	11843419
chemically mediated site-specific proteolysis. alteration of protein-protein interaction.	the design and synthesis of a novel iodine-labile serine protease inhibitor was realized by the use of an ecotin analogue containing allylglycine at position 84 in lieu of methionine. allylglycine-containing ecotins were synthesized by in vitro translation of the ecotin gene containing an engineered nonsense codon (tag) at the positions of interest. a misacylated suppressor trna activated with the unnatural amino acid allylglycine was employed for the suppression of the nonsense codons in a cell ...	2002	11851428
development of a sandwich elisa and comparison with pcr for the detection of f11 and f165 fimbriated escherichia coli isolates from septicaemic disease in farm animals.	the p fimbriae f11 and f165 that have been demonstrated on escherichia coli septicaemic strains in poultry and calves, respectively, possess a nearly identical major subunit that demonstrates a serological cross-reaction. a polyclonal antibody-based sandwich elisa (selisa) that was specific for both f11 and f165 fimbriated strains was compared with a pcr method to detect f11/f165 fimbriated strains, in a collection of e. coli strains isolated from diseased animals. of 298 isolates tested, 36 wer ...	2002	11852192
bacterial expression and purification of recombinant bovine fab fragments.	we have previously described a recombinant phagemid expression vector, pcombov, designed for the production of native sequence bovine monoclonal antibodies (mab) generated by antibody phage display. bovine mab fab fragments isolated from libraries constructed using pcombov in escherichia coli strain xl1-blue, which is routinely used for antibodies expressed on the surface of phage, were expressed at very low yields. therefore, a study was undertaken to determine optimal growth conditions for max ...	2002	11812221
analysis of a multicomponent thermostable dna polymerase iii replicase from an extreme thermophile.	this report takes a proteomic/genomic approach to characterize the dna polymerase iii replication apparatus of the extreme thermophile, aquifex aeolicus. genes (dnax, hola, and holb) encoding the subunits required for clamp loading activity (tau, delta, and delta') were identified. the dnax gene produces only the full-length product, tau, and therefore differs from escherichia coli dnax that produces two proteins (gamma and tau). nonetheless, the a. aeolicus proteins form a taudeltadelta' comple ...	2002	11859073
direct recovery of glutathione s-transferase by expanded bed adsorption: anion exchange as an alternative to metal affinity fusions.	the use of expanded beds of ion-exchange adsorbents for the direct recovery of a recombinant intracellular protein, glutathione s-transferase (gst), from unclarified escherichia coli homogenates is described. the results form the basis for a comparison between this approach for purifying gst and a chelating fusion strategy and highlight the need to consider the additional costs entailed by these more-complicated approaches. the separation performance was investigated with respect to choice of an ...	2002	11835138
regulation of photoreceptor phosphodiesterase (pde6) by phosphorylation of its inhibitory gamma subunit re-evaluated.	phosphorylation of the inhibitory gamma subunit (pgamma) of rod cgmp phosphodiesterase (pde6) has been reported to turn off visual excitation without the requirement for inactivation of the photoreceptor g-protein transducin. we evaluated the significance of pgamma phosphorylation for pde6 regulation by preparing pgamma stoichiometrically phosphorylated at thr(22) or at thr(35). phosphorylation of pgamma at either residue caused a minor decrease--not the previously reported increase--in the abil ...	2002	11741972
expression of receptors for verotoxin 1 from escherichia coli o157 on bovine intestinal epithelium.	human enterohaemorrhagic escherichia coli (ehec) infection most commonly arises, either directly or indirectly, from cattle, which act as a reservoir host for these bacteria. in man, ehec disease can be severe, whereas ehec do not normally cause disease in cattle. verotoxins (vts) are the main virulence factors in human disease but no role for vt has been ascribed in cattle; however, this study shows for the first time that vt receptor is expressed by the bovine intestinal tract. vt bound to cry ...	2002	11865842
biofilm bacteria: formation and comparative susceptibility to antibiotics.	the calgary biofilm device (cbd) was used to form bacterial biofilms of selected veterinary gram-negative and gram-positive pathogenic bacteria from cattle, sheep, pigs, chicken, and turkeys. the minimum inhibitory concentration (mic) and minimum biofilm eradication concentration (mbec) of ampicillin, ceftiofur, cloxacillin, oxytetracycline, penicillin g, streptomycin, tetracycline, enrofloxacin, erythromycin, gentamicin, tilmicosin, and trimethoprim-sulfadoxine for gram-positive and -negative b ...	2002	11989739
pharmacokinetics of ceftiofur in plasma and uterine secretions and tissues after subcutaneous postpartum administration in lactating dairy cows.	a study was conducted to measure concentrations of potentially active ceftiofur derivatives, in plasma, in uterine tissues (endometrium and caruncles) and in uterine secretions at different time points after a single subcutaneous administration of ceftiofur hydrochloride (excenel rtu sterile suspension) at the dose of 1 mg/kg body weight in holstein-friesian dairy cows. the animals (n=4) were injected within 24 h of calving, after expulsion of the foetal membranes. plasma, lochial fluid, caruncl ...	2002	11874524
genomic subtraction to identify and characterize sequences of shiga toxin-producing escherichia coli o91:h21.	to identify shiga toxin-producing escherichia coli genes associated with severe human disease, a genomic subtraction technique was used with hemolytic-uremic syndrome-associated o91:h21 strain ch014 and o6:h10 bovine strains. the method was adapted to the shiga toxin-producing e. coli genome: three rounds of subtraction were used to isolate dna fragments specific to strain ch014. the fragments were characterized by genetic support analysis, sequencing, and hybridization to the genome of a collec ...	2002	11976103
growth of escherichia coli o157:h7 in raw ground beef stored at 10 degrees c and the influence of competitive bacterial flora, strain variation, and fat level.	pure-culture broth-based models of the growth of escherichia coli o157:h7 have been used to estimate its behavior in ground beef, even though these models have not been adequately validated for this food product. this situation limits accurate estimates of the behavior of e. coli o157:h7 in ground beef and introduces uncertainties in risk assessments. in the present study, the growth of single and multiple strains of e. coli o157:h7 were measured in retail ground beef stored at 10 degrees c for ...	2002	12380736
mechanisms involved in milk endogenous proteolysis induced by a lipopolysaccharide experimental mastitis.	experimental mastitis has been induced by the lipopolysaccharide (lps) of escherichia coli on six dairy cows in order to study the mechanisms involved in milk endogenous proteolysis during the inflammatory process. variations in somatic cell count (scc), plasmin activity, and total casein (cn) content were measured, and proteose-peptone content and the percentage of ph 4.6 insoluble peptides including gamma-cn have been considered as indicators of endogenous proteolysis. furthermore, polymorphon ...	2002	12416808
influence of dry period bacterial intramammary infection on clinical mastitis in dairy cows.	milk samples were taken from 1920 quarters (480 cows, six herds) on four occasions to examine the relationship between quarter level intramammary infection (imi) during the dry period and clinical mastitis in the next lactation. all quarters were sampled at drying off and within 1 wk of calving, and two quarters from each cow were sampled both 0 to 7 and 8 to 14 d before calving. milk samples were collected from all cases of clinical mastitis during the following lactation. logistic regression m ...	2002	12416812
photocatalytic oxidation of bacteria, bacterial and fungal spores, and model biofilm components to carbon dioxide on titanium dioxide-coated surfaces.	we report carbon mass balance and kinetic data for the total oxidation of cells, spores, and biomolecules deposited on illuminated titanium dioxide surfaces in contact with air. carbon dioxide formation by photocatalytic oxidation of methanol, glucose, escherichia coli, micrococcus luteus, bacillus subtilis (cells and spores), aspergillus niger spores, phosphatidylethanolamine, bovine serum albumin, and gum xanthan was determined as a function of time. the quantitative data provide mass balance ...	2002	12188373
antibacterial activity of pepsin-digested lactoferrin on foodborne pathogens in buffered broth systems and ultra-high temperature milk with edta.	to evaluate the antimicrobial activity in peptone yeast extract glucose (pyg) broth and ultra-high temperature (uht) milk of bovine lactoferrin hydrolysate (lfh) with pepsin against the foodborne pathogens salmonella stanley, escherichia coli, listeria monocytogenes and staphylococcus aureus.	2002	12392532
observation of additional calcium ion in the crystal structure of the triple mutant k56,120,121m of bovine pancreatic phospholipase a2.	phospholipase a(2) catalyses hydrolysis of the ester bond at the c2 position of 3-sn-phosphoglycerides. here we report the 1.9a resolution crystal structure of the triple mutant k56,120,121m of bovine pancreatic phospholipase a(2). the structure was solved by molecular replacement method using the orthorhombic form of the recombinant phospholipase a(2). the final protein model contains all the 123 amino acid residues, two calcium ions, 125 water molecules and one 2-methyl-2-4-pentanediol molecul ...	2002	12460575
engineering s-protein fragments of bovine ribonuclease a for targeted drug delivery.	high affinity interaction between s-protein and s-peptide fragments of bovine pancreatic rnase a has been recently used for construction of molecular vehicles for targeted drug delivery. the vehicle is assembled as a complex of drug carrier conjugated s-protein with s-peptide-tagged targeting protein. to avoid random chemical crosslinking of drug carriers to s-protein, we constructed a mutant 16-124aa fragment of rnase a in which 122ala is replaced with a cysteine residue. the mutant and the cor ...	2002	12460770
bovine lymphocytes express functional receptors for escherichia coli shiga toxin 1.	interactions of shiga toxins (stxs) and immune cells contribute to the pathogenesis of diseases due to stx-producing escherichia coli (stec) infections in humans and facilitate the persistence of infection in asymptomatically infected cattle. our recent findings that bovine b and t lymphocytes express gb(3)/cd77, the human stx-receptor, prompted us to determine whether the bovine homologue also mediates binding and internalization of stx1. in fact, stx1 holotoxin and recombinant b subunit (rstxb ...	2002	12495672
[the correcting role of autonomous 3'-->5' exonucleases in mammalian multienzyme dna polymerase complexes].	a study was made of the correcting role of autonomous 3'-->5' exonucleases (ae) contained in multienzyme dna polymerase complexes of rat hepatocytes or calf thymocytes. dna was synthesized on phage psi x174 amber3 or m13mp2 primer-templates, and used to transfect escherichia coli spheroplasts. frequencies were estimated for direct and reverse mutations resulting from mistakes made in the course of in vitro dna synthesis. the mistake rate of the hepatocytic complex was estimated at 3 x 10(-6) wit ...	2002	12500544
cloning, characterization, and expression studies in escherichia coli of growth hormone cdnas from indian zebu cattle, reverine buffalo, and beetal goat.	the growth hormone cdnas from three different economically important animal species of indian origin viz., indian zebu cattle (bos indicus), indian reverine buffalo (bubalus bubalis), and beetal goat (capra hircus) were isolated by the rt-pcr technique. the amplified product was then cloned into phagemid pbluescriptiiks- and the nucleotide sequence of the entire 573 base coding region for each product was determined. the genetic sequences as well as the translated protein sequence of these rumin ...	2002	12517072
enterohemorrhagic escherichia coli o157: epidemiology and ecology in bovine production environments.	enterohemorrhagic escherichia coli, particularly the o157(:h7) serogroup, has become a worldwide public health concern. since cattle feces are often implicated as the source of e. coli o157 in human infections, considerable resources have been devoted to defining the epidemiology and ecology of e. coli o157 in cattle environments so that control might begin at the farm level. diagnostic limitations and the complexity of often interrelated microbial, animal, herd, environmental and production fac ...	2002	12665108
sympathoadrenal and immune system activation during the periparturient period and their association with bovine coliform mastitis. a review.	increased incidence of clinical mastitis in high-yielding cows during early lactation has been attributed to a depressed functional capacity of the immune system. sympathoadrenal factors are known to play an important role in modulating the host susceptibility and resistance to infectious diseases. of primary importance in combating acute intramammary infections are polymorphonuclear leukocytes (pmn), as they represent one of the early lines of immunological defense. the release of stress hormon ...	2003	12670012
comparison of shiga toxin production by hemolytic-uremic syndrome-associated and bovine-associated shiga toxin-producing escherichia coli isolates.	there is considerable diversity among shiga toxin (stx)-producing escherichia coli (stec) bacteria, and only a subset of these organisms are thought to be human pathogens. the characteristics that distinguish stec bacteria that give rise to human disease are not well understood. stxs, the principal virulence determinants of stec, are thought to account for hemolytic-uremic syndrome (hus), a severe clinical consequence of stec infection. stxs are typically bacteriophage encoded, and their product ...	2003	12571029
pathogen survival in swine manure environments and transmission of human enteric illness--a review.	the influence of zoonotic pathogens in animal manure on human health and well-being as a direct or indirect cause of human enteric illness is examined. available international data are considered, but the study is focused on the developing situation in western canada, where it is certain there will be further rapid growth in livestock numbers, particularly hogs. major pathogens considered are escherichia coli o157:h7, salmonella, campylobacter, yersinia, cryptosporidium, and giardia. canada is n ...	2003	12708660
geographical variation in ribotype profiles of escherichia coli isolates from humans, swine, poultry, beef, and dairy cattle in florida.	waters impacted by fecal pollution can exact high risks to human health and can result in financial losses due to closures of water systems used for recreation and for harvesting seafood. identifying the sources of fecal pollution in water is paramount in assessing the potential human health risks involved as well as in assessing necessary remedial action. recently, various researchers have used the ribotyping method to identify sources of bacterial indicators (escherichia coli and enterococci) ...	2003	12571033
verotoxin-producing escherichia coli in spain: prevalence, serotypes, and virulence genes of o157:h7 and non-o157 vtec in ruminants, raw beef products, and humans.	in spain, as in many other countries, verotoxin-producing escherichia coli (vtec) strains have been frequently isolated from cattle, sheep, and foods. vtec strains have caused seven outbreaks in spain (six caused by e. coli o157:h7 and one by e. coli o111:h- [nonmotile]) in recent years. an analysis of the serotypes indicated serological diversity. among the strains isolated from humans, serotypes o26:h11, o111:h-, and o157:h7 were found to be more prevalent. the most frequently detected serotyp ...	2003	12671177
presence and characterization of extraintestinal pathogenic escherichia coli virulence genes in f165-positive e. coli strains isolated from diseased calves and pigs.	the virulence genotype profile and presence of a pathogenicity island(s) (pai) were studied in 18 strains of f165-positive escherichia coli originally isolated from diseased calves or piglets. on the basis of their adhesion phenotypes and genotypes, these extraintestinal pathogenic strains were classified into three groups. the f165 fimbrial complex consists of at least two serologically and genetically distinct fimbriae: f165(1) and f165(2). f165(1) is encoded by the foo operon (pap-like), and ...	2003	12682117
thermal and urea-induced unfolding of the marginally stable lac repressor dna-binding domain: a model system for analysis of solute effects on protein processes.	thermodynamic and structural evidence indicates that the dna binding domains of lac repressor (laci) exhibit significant conformational adaptability in operator binding, and that the marginally stable helix-turn-helix (hth) recognition element is greatly stabilized by operator binding. here we use circular dichroism at 222 nm to quantify the thermodynamics of the urea- and thermally induced unfolding of the marginally stable laci hth. van't hoff analysis of the two-state unfolding data, highly a ...	2003	12590610
vaccination strategies for reducing clinical severity of coliform mastitis.	brief history and extensive published field efficacy data of the two rough ("r") bacterial mutants utilized in commercial preparations of the core antigen bacterins escherichia coli o111:b4 (strain j5) and salmonella typhimurium re-17 are summarized. particular dosage schedules and routes of administration of coliform mastitis bacterins are compared for their associated ecacy. practical concerns in employing a coliform mastitis vaccination program are discussed. characteristics of farms using co ...	2003	12682942
opsonic activity of serum and whey from cows immunized with the ferric citrate receptor.	the effects of immunizing dairy cows with the ferric citrate receptor, feca, on the opsonic activity of serum and whey were measured in a phagocytosis assay. fifteen cows were assigned to five blocks of three cows based on date of expected parturition. cows within a block were randomly assigned to one of three treatments: 1) feca immunization, 2) immunization with a commercially available escherichia coli j5 bacterin, and 3) unimmunized controls. cows were challenged at approximately 21 dim by i ...	2003	12613859
antimicrobial resistance of bacteria isolated from dairy cow milk samples submitted for bacterial culture: 8,905 samples (1994-2001).	to determine whether antimicrobial resistance patterns of major mastitis pathogens isolated from milk samples from dairy cows have changed over time.	2003	12784967
evidence for a cd14- and serum-independent pathway in the induction of endotoxin-tolerance in human monocytes and thp-1 monocytic cells.	lipopolysaccharide (lps) stimulation of macrophages or monocytes is believed to occur via a serum- and cd14-dependent signaling pathway via toll-like receptor 4 (tlr4). we sought to determine whether serum and/or cd14 are required for lps to induce the endotoxin-tolerant state in human monocytes. lps treatments were performed in the presence or absence of an anti-cd14 monoclonal antibody and with or without fetal bovine serum. endotoxin tolerance was assessed after an 18-h exposure (pretreatment ...	2003	12688542
molecular cloning and heterologous expression in e. coli of cytochrome p45017alpha. comparison of structural and functional properties of substrate-specific cytochromes p450 from different species.	to elucidate the nature of substrate specificity and intrinsic mechanism of hydroxylation of steroids, in the present work we carried out molecular cloning and heterologous expression of cdna for three new forms of cytochrome p45017alpha from species of the bovidae family (sheep, goat, and bison), which catalyze 17alpha-hydroxylation of both progesterone (p4) or pregnenolone (p5) and 17,20-lyase reaction resulting in cleavage of side chain with formation of c(19)-steroids. recombinant cytochrome ...	2003	12693981
shiga toxin-producing escherichia coli (stec) isolated from healthy dairy cattle in southern brazil.	over a period of 1 year, the production of verotoxin was investigated in 1127 escherichia coli isolated from 243 dairy cattle from 60 small farms in southern brazil. vero cell assay was used to detect toxins in culture supernatants from e. coli isolated from bovine feces. shiga toxin-producing e. coli (stec) detection rates were 95% (57 of 60) for farms and 49% (119 of 243) for cattle. prevalence of stec-positive cattle in the farms ranged from 0 to 100%. ninety-six percent (315 of 327) of the s ...	2003	12695042
2-methyl-3-hydroxybutyryl-coa dehydrogenase deficiency is caused by mutations in the hadh2 gene.	2-methyl-3-hydroxybutyryl-coa dehydrogenase (mhbd) deficiency is a novel inborn error of isoleucine degradation. in this article, we report the elucidation of the molecular basis of mhbd deficiency. to this end, we purified the enzyme from bovine liver. maldi-tof mass spectrometry analysis revealed that the purified protein was identical to bovine 3-hydroxyacyl-coa dehydrogenase type ii. the human homolog of this bovine enzyme is a short-chain 3-hydroxyacyl-coa dehydrogenase, also known as the " ...	2003	12696021
antibiotic resistance in animals.	there is currently no systematic surveillance or monitoring of antibiotic resistance in australian animals. registration of antibiotics for use in animals is tightly controlled and has been very conservative. fluoroquinolones have not been registered for use in food producing animals and other products have been removed from the market because of human health concerns. in the late 1970s, the animal health committee coordinated a survey of resistance in salmonella and escherichia coli isolates fr ...	2003	12807287
surveillance for antibiotic resistance in veterinary pathogens from the perspective of a regional diagnostic laboratory.	the toowoomba veterinary laboratory tests for antibiotic resistance through passive surveillance of bacterial pathogens from diseased, frequently intensively managed, animals. testing is carried out on the basis of the number of animals involved, the nature and severity of the disease and the identity and significance of the bacterium, the results guiding the submitting veterinarian in implementing appropriate treatment. the antibiotics chosen for testing are those that are currently registered ...	2003	12807288
influence of agitation, inoculum density, ph, and strain on the growth parameters of escherichia coli o157:h7--relevance to risk assessment.	foods may differ in at least two key variables from broth culture systems typically used to measure growth kinetics of enteropathogens: initial population density of the pathogen and agitation of the culture. the present study used nine escherichia coli o157:h7 strains isolated from beef and associated with human illness. initial kinetic experiments with one e. coli o157:h7 strain in brain-heart infusion (bhi) broth at ph 5.5 were performed in a 2 x 2 x 3 factorial design, testing the effects of ...	2003	12706036
bayesian methods for estimating pathogen prevalence within groups of animals from faecal-pat sampling.	pathogens such as escherichia coli o157:h7 and campylobacter spp. have been implicated in outbreaks of food poisoning in the uk and elsewhere. domestic animals and wildlife are important reservoirs for both of these agents, and cross-contamination from faeces is believed to be responsible for many human outbreaks. appropriate parameterisation of quantitative microbial-risk models requires representative data at all levels of the food chain. our focus in this paper is on the early stages of the f ...	2003	12706055
forage feeding to reduce preharvest escherichia coli populations in cattle, a review.	although escherichia coli are commensal organisms that reside within the host gut, some pathogenic strains of e. coli can cause hemorrhagic colitis in humans. the most notable enterohemorrhagic e. coli (ehec) strain is o157:h7. cattle are asymptomatic natural reservoirs of e. coli o157:h7, and it has been reported that as many as 30% of all cattle are carriers of this pathogen, and in some circumstances this can be as high as 80%. feedlot and high-producing dairy cattle are fed large grain ratio ...	2003	12703622
occurrence and characteristics of cs31a antigen-producing escherichia coli in calves with diarrhoea and septicaemia in argentina.	cs31a is a k88-related non-fimbrial adhesin first described on escherichia coli strains isolated from diarrhoeic and septicaemic calves. in this report, cs31a antigen was screened by immunological methods and confirmed by pcr among bovine e. coli isolates. in addition, cs31a-producing strains were characterized with respect to different fimbrial antigens, o-serogroup and other properties related to virulence. faecal or tissue specimens of 100 diarrhoeic or septicaemic calves and 27 older cattle ...	2003	12710494
hemolytic-uremic syndrome associated with enterohemorrhagic escherichia coli o26:h infection and consumption of unpasteurized cow's milk.	enterohemorrhagic escherichia coli (ehec) o26 has emerged as a significant cause of hemolytic-uremic syndrome (hus). the source and the vehicle of contamination with ehec o26 are not often identified. we report two austrian cases of hus due to e. coli o26:h- affecting an 11-month-old boy and a 28-month-old girl in which transmission through unpasteurized cow's milk was positively identified.	2003	12718809
a new method for enzymatic preparation of isopentenyladenine-type and trans-zeatin-type cytokinins with radioisotope-labeling.	we describe a new enzymatic reaction method for the preparation of the radioisotope-labeled cytokinins isopentenyladenine (ip), trans-zeatin (tz), and their ribosides. the method is based on the three enzyme activities of an adenylate isopentenyltransferase (ipt; ec 2.5.1.27) from arabidopsis thaliana, an alkaline phosphatase (ec 3.1.3.1) from calf intestine, and a purine-nucleoside phosphorylase (ec 2.4.2.1) from escherichia coli. the a. thaliana ipt, atipt7, utilized both dimethylallyldiphosph ...	2003	12728344
thermal inactivation of escherichia coli o157:h7 in ground beef supplemented with sodium lactate.	a study was conducted to investigate the antimicrobial effect of sodium lactate (nal) (0, 1.5, 3.0, and 4.5%) on the survival of escherichia coli o157:h7 in 93% lean ground beef. samples inoculated with a mixture of four strains of e. coli o157:h7 (10(7) to 10(8) cfu/g) were subjected to immersion heating in a water bath stabilized at 55, 57.5, 60, 62.5, or 65 degrees c. results of statistical analysis indicated that the heating temperature was the only factor affecting the decimal reduction tim ...	2003	12696693
transfer of a rifampicin-resistant escherichia coli strain among feedlot cattle.	to determine the incidence of transfer of a naturally occurring rifampicin-resistant strain of escherichia coli (rrec) among cattle in a research feedlot.	2003	12859774
glutamate counteracts the denaturing effect of urea through its effect on the denatured state.	the urea induced equilibrium denaturation behavior of glutaminyl-trna synthetase from escherichia coli (glnrs) in 0.25 m potassium l-glutamate, a naturally occurring osmolyte in e. coli, has been studied. both the native to molten globule and molten globule to unfolded state transitions are shifted significantly toward higher urea concentrations in the presence of l-glutamate, suggesting that l-glutamate has the ability to counteract the denaturing effect of urea. d-glutamate has a similar effec ...	2003	12844489
efficient hsp90-independent in vitro activation by hsc70 and hsp40 of duck hepatitis b virus reverse transcriptase, an assumed hsp90 client protein.	hsp90 is a specialized chaperone that controls the activity of many key regulator proteins such as steroid hormone receptors (shrs). hormone binding, and therefore shr activation, requires hsp90, which is loaded onto the receptors by a series of events involving hsp70, hsp40, hop, and p23. the reverse transcriptase (rt) of hepatitis b viruses, small dna-containing viruses that replicate via an rna intermediate, has been reported to depend similarly on hsp90 for enzymatic activity. using an in vi ...	2003	12851401
preparation of recombinant rat eosinophil-associated ribonuclease-1 and -2 and analysis of their biological activities.	rat eosinophils contain eosinophil-associated ribonucleases (ears) in their granules. ears are thought to be synthesized as pre-forms and stored in the granules as mature forms. however, the n-terminal amino acid of mature ear-1 and ear-2 is still controversial. therefore, we prepared two recombinant mature forms of ear-1 and ear-2 in which the n-terminal amino acids are ser24 (s) [ear-1 (s) and ear-2 (s)] and gln26 (q) [ear-1 (q) and ear-2 (q)], and analyzed their biological activities by compa ...	2003	12853122
factors influencing the shedding of verocytotoxin-producing escherichia coli o157 by beef suckler cows.	a study was designed to investigate management factors that might influence the shedding of verocytotoxin-producing escherichia coli (vtec) o157 by beef cows in scotland, where there is a particularly high rate of human infection. thirty-two herds were visited at least monthly over approximately 1 year for collection of fresh faecal pat samples and information on management factors. the faecal pat samples were tested for vtec o157 by established culture and immunomagnetic separation methods. que ...	2003	12729199
sensitivity of methods for the isolation of escherichia coli o157 from naturally infected bovine faeces.	at present, no standard protocol has been described to detect the presence of escherichia coli o157 in cattle faeces. therefore, the sensitivity of 26 different isolation methods was determined in order to recommend a method of choice. faeces samples from 17 different beef cattle at a farm previously found positive for e. coli o157 were subdivided into a total of 40 samples. it was not known whether the 17 cattle shed e. coli o157 at the time of sampling. at another farm where cattle have been f ...	2003	12829388
genetic characterization of escherichia coli populations from host sources of fecal pollution by using dna fingerprinting.	escherichia coli isolates were obtained from common host sources of fecal pollution and characterized by using repetitive extragenic palindromic (rep) pcr fingerprinting. the genetic relationship of strains within each host group was assessed as was the relationship of strains among different host groups. multiple isolates from a single host animal (gull, human, or dog) were found to be identical; however, in some of the animals, additional strains occurred at a lower frequency. rep pcr fingerpr ...	2003	12732525
origin of contamination and genetic diversity of escherichia coli in beef cattle.	the possible origin of beef contamination and genetic diversity of escherichia coli populations in beef cattle, on carcasses and ground beef, was examined by using random amplification of polymorphic dna (rapd) and pcr-restriction fragment length polymorphism (pcr-rflp) analysis of the flic gene. e. coli was recovered from the feces of 10 beef cattle during pasture grazing and feedlot finishing and from hides, carcasses, and ground beef after slaughter. the 1,403 e. coli isolates (855 fecal, 320 ...	2003	12732550