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oxidation, cross-linking, and insolubilization of recombinant tropoelastin by purified lysyl oxidase.the use of recombinant human tropoelastin (rte) and selected variants thereof as substrates for the assay of lysyl oxidase activity in vitro was explored. the possibility was also assessed that an insoluble elastin-like product could be generated from this elastin precursor in the absence of other macromolecules found associated with elastin in vivo. rte was more efficiently oxidized by lysyl oxidase than the insoluble chick aorta elastin substrate conventionally used. anionic amphiphilic elasti ...19938098038
structure and copy number analyses of pap-, sfa-, and afa-related gene clusters in f165-positive bovine and porcine escherichia coli isolates.pathogenic f165-positive escherichia coli isolates of porcine and bovine origin possess gene clusters related to extraintestinal e. coli fimbrial operons pap, sfa, and afai. probes from different segments of the pap, sfa, and afai operons were used in southern hybridization to analyze 18 f165-positive, mannose-resistant hemagglutinating e. coli isolates possessing pap- and sfa-, pap- and afa-, or pap-related sequences. only single copies of the pap-, sfa-, or afa-related sequences were found amo ...19938099065
complementary dna sequence of bovine cpn10 (hsp10), a chaperone protein from mitochondria.a cdna sequence encoding a chaperone protein from bovine heart mitochondria is described. it is deduced from overlapping partial cdnas amplified in polymerase chain reactions from bovine heart cdna, using in the first instance mixtures of synthetic oligonucleotide primers based on the incomplete sequence of the cpn10 (hsp10) chaperone protein from rat liver mitochondria. the encoded bovine protein sequence is 101 amino acids in length. by analogy with the rat homologue it is likely that the init ...19938104547
milk from hyperimmunized dairy cows as a source of a novel biological response modifier.laboratory investigations have established that hyperimmunization of dairy cows with a polyvalent bacterial vaccine results in the secretion of biologically active substances into the milk. one of these factors, a low molecular weight anti-inflammatory agent (himf), has been studied in detail. the evidence supports the hypothesis that himf suppresses inflammation by inhibiting neutrophil emigration. additionally, the experiments suggested that himf was capable of modifying the host response to i ...19938317311
radiotelemetry temperature responses of mammary gland and body to intramammary injection of escherichia coli endotoxin or streptococcus agalactiae in lactating dairy cows.to investigate the feasibility of using changes in body or mammary temperature to detect mastitis, radiotransmitters were implanted midway between rear udder quarters and in the peritoneal cavity of 5 holstein cows (1 to 3 months in lactation) housed in an environmental chamber (16 +/- 2 c; lights on 7:00 am to 11:00 pm). after a 6-week control period, escherichia coli endotoxin (0.5 mg) was injected after the morning milking into left rear teat cisterns via the teat canal. wisconsin mastitis te ...19938317774
endotoxemia and brain bilirubin in the rat.to investigate the possible role of sepsis with endotoxemia in kernicterus, we studied the effect of endotoxin on accumulation of bilirubin and albumin in rat brain. male sprague-dawley rats were given escherichia coli endotoxin i.v. after 150 min 10 microci 125i-bovine serum albumin was given intravenously, followed by a 1-hour bilirubin infusion. brain bilirubin was significantly higher in the endotoxin group than in the controls (1.34 +/- 0.47 vs. 0.83 +/- 0.31 microgram/g, p < 0.05). however ...19938324097
analysis of tandem, multiple genes encoding 30-kda membrane proteins in pasteurella haemolytica a1.a number of outer membrane proteins (omps), including a 30-kda protein, may be important in eliciting immunity to pasteurella haemolytica a1, the causative agent of bovine pneumonic pasteurellosis. to better understand the nature of the 30-kda antigen, several genes encoding this protein were sequenced. sequence analysis revealed that three separate genes encoding similar, yet distinct, versions of the 30-kda protein are tandemly arranged on the p. haemolytica a1 chromosome. the genes appear to ...19938335249
babesia bovis: characterization of the t helper cell response against the 42-kda merozoite surface antigen (msa-1) in cattle.the babesia bovis major merozoite surface antigen (msa-1) is a 42-kda integral membrane glycoprotein previously shown to induce immunodominant antibody responses in cattle protectively immune to b. bovis and to induce neutralizing antibody. recent studies have also shown that msa-1 b cell epitopes common to new world strains of b. bovis are not present in either israel or australia strains. to understand the potential role of this protein in protective immunity, t helper cell responses specific ...19938344411
use of tellurite for the selection of verocytotoxigenic escherichia coli o157.potassium tellurite was assessed for the selection of verocytotoxigenic (vt+) escherichia coli o157. mics were higher for vt+ e. coli o157 than for other strains of e. coli and for aeromonas spp. macconkey medium containing sorbitol, tellurite and cefixime (tc-smac) permitted the growth of vt+ e. coli o157 and shigella sonnei but partially or completely inhibited the growth of 67% of other strains of e. coli and all or most strains of other sorbitol-non-fermenting species tested. of 391 rectal s ...19938345511
rab gdp dissociation inhibitor as a general regulator for the membrane association of rab proteins.rab proteins comprise a family of small gtpases that serve a regulatory role in membrane traffic. these proteins are in part cytosolic and in part associated with the membranes of specific exocytic and endocytic organelles. smg p25a/rab3a gdi, a cytosolic protein which inhibits the dissociation of gdp from smg p25a/rab3a, sec4p, and rab11, has also been found to prevent association of rab3a with the membrane. in this study, we have used madin-darby canine kidney cells permeabilized with the bact ...19938349690
outbreaks of salmonella dublin infection among calves on a dairy farm applying salmonella bacterins in zambia.in zambia, a dairy farm keeping about 600 cows and self-contained calves had applied s. dublin and s. typhimurium bacterins to pregnant cows and calves in combination with all-in all-out pen system for rearing calves. only relatively small scale outbreaks of s. dublin infection occurred repeatedly in these years from 1989 to 1991 among fattening calves on the farm. the results obtained from the epizootiological study suggest that the preventive measures including the vaccination with salmonella ...19938357934
abundant bacterial expression and reconstitution of an intrinsic membrane-transport protein from bovine mitochondria.the oxoglutarate carrier, an intrinsic membrane-transport protein of the inner membranes of bovine-heart mitochondria, has been expressed at an abundant level in escherichia coli. it accumulates in the bacterium as inclusion bodies, and none of the protein was detected in the bacterial inner membrane. the mitochondrial adp/atp carrier, a member of the same super-family of transport proteins as the oxoglutarate carrier, has also been expressed in e. coli. however, the expression of the adp/atp ca ...19938363582
ibuprofen treatment of endotoxin-induced mastitis in cows.ibuprofen treatment was compared with saline solution treatment in an endotoxin-induced experimental model of bovine mastitis. acute mastitis was induced in healthy lactating holstein cows (n = 12) by intramammary inoculation of 1 mg of escherichia coli 026:b6 lipopolysaccharide in a single quarter per cow. cows were assigned at random to ibuprofen (25 mg/kg of body weight, iv, n = 6) or 0.9% sodium chloride solution control (1.25 ml/kg, iv, n = 6) treatment groups. ibuprofen or saline solution ...19938368609
structural stability of bacillus thuringiensis delta-endotoxin homolog-scanning mutants determined by susceptibility to proteases.forty homolog-scanning (double-reciprocal-crossover) mutant proteins of two bacillus thuringiensis delta-endotoxin genes (cryiaa and cryiac) were examined for potential structural alterations by a series of proteolytic assays. three groups of mutants could be identified. group 1, consisting of 13 mutants, showed no delta-endotoxin present during overexpression conditions in escherichia coli (48 h at 37 degrees c, with a ptac promoter). these mutants produced full-sized delta-endotoxin detectable ...19938368834
isolation of bovine kidney leucine aminopeptidase cdna: comparison with the lens enzyme and tissue-specific expression of two mrnas.aminopeptidases catalyze the hydrolysis of amino acid residues from the amino terminus of peptide substrates. leucine aminopeptidase (lap) from bovine lens is the best characterized aminopeptidase and the only lap for which the amino acid sequence was determined by protein sequencing. using this sequence information, we isolated a bovine kidney lap cdna and compared its deduced amino acid sequence to the published amino acid sequence for bovine lens lap. overall, the sequences are highly conserv ...19938369298
taurolidine: in vitro activity against multiple-antibiotic-resistant, nosocomially significant clinical isolates of staphylococcus aureus, enterococcus faecium, and diverse enterobacteriaceae.taurolidine at < or = 1,250 micrograms/ml killed all 37 isolates of multiple-antibiotic-resistant staphylococcus aureus (n = 9), enterococcus faecium (n = 17), and enterobacteriaceae (n = 11). time-kill experiments disclosed that bovine serum (65% v/v) only marginally retarded the bactericidal activity of 2,000 and 1,000 micrograms/ml of taurolidine against the various strains. taurolidine at 2,000 micrograms/ml did not antagonize the bactericidal activity of 50% (v/v) fresh human serum against ...19938370323
photolesions in dna upon 193 nm excitation.aqueous solutions of plasmid (pbr322 and ptz18r) and calf thymus dna were excited by 20 ns laser pulses at 193 nm. the quantum yields of single-and double-strand break formation, interstrand cross-links, locally denatured sites, (6-4)photoproducts and biological inactivation (phi ssb, phi dsb, phi icl, phi lds, phi 6-4 and phi ina, respectively) were measured. the quantum yields are virtually independent of intensity, demonstrating a one-quantum process. the obtained values in aerated neutral so ...19938378435
cytochrome bo from escherichia coli: identification of haem ligands and reaction of the reduced enzyme with carbon monoxide.inner membranes were prepared from escherichia coli strain rg 145, which is deficient in cytochrome bd, but overexpresses cytochrome bo [au and gennis (1987) j. bacteriol. 169, 3237-3242]. the latter was purified 7-fold by extracting the membranes with octyl beta-d-glucopyranoside, followed by chromatography on deae-sepharose, yielding 150 mg of protein/150 g wet weight of cells. optical e.p.r. and low-temperature m.c.d. (magnetic circular dichroism) spectroscopies were used to investigate the n ...19938382047
the short loop between epidermal growth factor-like domains 4 and 5 is critical for human thrombomodulin function.thrombomodulin (tm) is a cofactor for activation of protein c by thrombin. we showed that 80-90% of this cofactor activity is lost by oxidation of met388, located within the short interdomain loop between epidermal growth factor-like domains 4 and 5 (glaser, c. b., morser, j., clarke, j. h., blasko, e., mclean, k., kuhn, i., chang, r.-j., lin, j.-h., vilander, l., andrews, w. h., and light, d. r. (1992) j. clin. invest. 90, 2565-2573). for each of the 3 amino acids of the loop, site-specific mut ...19938384206
mitochondrial cardiolipin in diverse eukaryotes. comparison of biosynthetic reactions and molecular acyl species.cardiolipin, a unique dimeric phospholipid of bacteria and mitochondria, can be synthesized by two alternative pathways discovered in rat and escherichia coli, respectively. in mitochondrial preparations from fungi (saccharomyces cerevisiae, neurospora crassa), higher plants (phaseolus aureus), molluscs (mytilus edulis) and mammals (rat liver, bovine adrenal gland), cardiolipin was synthesized from cdp-diacylglycerol and phosphatidylglycerol, suggesting a common eukaryotic mechanism of cardiolip ...19938385010
the alpha-type 85-kda subunit of phosphatidylinositol 3-kinase is phosphorylated at tyrosines 368, 580, and 607 by the insulin receptor.we have shown previously that insulin stimulated the tyrosine phosphorylation of the alpha-type 85-kda subunit (p85) of phosphatidylinositol (pi) 3-kinase in vitro and in vivo. in the present work, we identified the major tyrosine phosphorylation sites of the alpha-type p85 by the insulin receptor. [32p]phosphopeptides obtained from lysylendopeptidase digestion of phosphorylated alpha-type p85 in intact cells after insulin treatment were analyzed using reverse-phase high performance liquid chrom ...19938385099
expression of human liver 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase in escherichia coli. role of n-2 proline in degradation of the protein.human liver 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase is 96% identical to the rat and bovine liver enzymes, and all of the critical catalytic and substrate binding residues in both the kinase and bisphosphatase domains are conserved in the three enzymes. however, in contrast to rat liver 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase, which is readily expressed in an escherichia coli t-7 rna polymerase-based expression system, the human liver bifunctional enzyme could not be exp ...19938385136
formation of a stable adduct between ubiquitin and the arabidopsis ubiquitin-conjugating enzyme, atubc1+.ubiquitin conjugating enzymes (e2s) are an integral part of a multienzyme pathway that ligates ubiquitin to intracellular target proteins. this ligation has been implicated in a number of fundamental processes including protein degradation, cell cycle progression, dna repair, and organelle biogenesis. to function, e2s form a labile thiol-ester intermediate between a specific cysteine within the e2 and the carboxyl terminus of ubiquitin; this high energy intermediate then serves as the donor for ...19938386169
cytochrome bo from e. coli does not exhibit the same proton transfer characteristics as the bovine cytochrome c oxidase during oxygen reduction.the reaction where fully reduced cytochrome bo from e. coli partially reduces dioxygen has been characterized with respect to the kinetics of the associated proton uptake, and with respect to the ph- and d2o-sensitivity of the electron transfer reactions. a monophasic proton uptake with a rate constant of about 8 x 10(3) s-1 and a stoichiometry of 0.8 h+/bo were recorded, using the indicator dye, cresol red, at ph 8.2. the electron transfer reactions were independent of ph in the range 6.0-9.5 a ...19938391485
calf small intestine receptors for k99 fimbriated enterotoxigenic escherichia coli.non-acid and acid glycolipids were isolated from the small intestine of a newborn calf and tested for the ability to bind escherichia coli carrying k99 fimbriae. the bacteria did not bind to any of the non-acid glycolipids, whereas in the acid glycolipid fraction several gangliosides were detected which bind to k99 fimbriae. gangliosides capable of binding k99 fimbriated e. coli were characterized as neugc-gm3, neugc-gm2, neugc-gd1a neuac-spg and neuac-spg. no binding was detected to neuac-gm3 a ...19938391499
phosphorylation of mg(2+)-dependent protein phosphatase alpha (type 2c alpha) by casein kinase ii.in this study we show that rat mg(2+)-dependent protein phosphatase alpha (mpp alpha) expressed in saccharomyces cerevisiae cells was phosphorylated on serine residues in vivo. the recombinant rat mpp alpha purified from escherichia coli cells harboring an expression vector was phosphorylated in vitro by casein kinase ii, but not by casein kinase i, to 1.5 mol phosphate per mol enzyme protein. analysis by phosphopeptide mapping and amino acid analysis suggested that the sites of both in vivo and ...19938395836
dna unwinding by replication protein a is a property of the 70 kda subunit and is facilitated by phosphorylation of the 32 kda subunit.replication protein a (rp-a) is a heterotrimeric single-stranded dna binding protein with important functions in dna replication, dna repair and dna recombination. we have found that rp-a from calf thymus can unwind dna in the absence of atp and mgcl2, two essential cofactors for bona fide dna helicases (georgaki, a., strack, b., podust, v. and hübscher, u. febs lett. 308, 240-244, 1992). dna unwinding by rp-a was found to be sensitive to mgcl2, atp, heating and freezing/thawing. escherichia col ...19938396234
the proton pumping activity of h(+)-atpases: an improved fluorescence assay.a new method for the estimation of steady-state delta ph, and the rate of acidification, by h(+)-atpases (and other proton transporters) in inverted membrane vesicles is described. the method is based on a combination of two widely used fluorescent delta ph probes, 9-aminoacridine and 9-amino-6-chloro-2-methoxyacridine. it is demonstrated that 9-amino-6-chloro-2-methoxyacridine fluorescence quenching, which is very sensitive to small ph gradients, is not sensitive to the magnitude of large ph gr ...19938399374
mammalian polypeptide chain release factor and tryptophanyl-trna synthetase are distinct proteins.a very high (approximately 90%) structural similarity exists between the bovine, human and murine tryptophanyl-trna synthetases (wrs), and quite unexpectedly the rabbit polypeptide chain release factor (erf). this similarity may point to a very close resemblance or identity between these proteins involved in distinct steps of protein synthesis, or inadvertently to an incorrect assignment of the clone reported to encode erf, since the structure of clones encoding wrs were confirmed by peptide seq ...19938404867
replicon typing characterization of plasmids encoding resistance to gentamicin and apramycin in escherichia coli and salmonella typhimurium isolated from human and animal sources in belgium.escherichia coli and salmonella strains with plasmids conferring resistance to gentamicin and apramycin have been isolated with increasing frequency both from cattle and hospital patients in belgium. the apramycin-gentamicin resistance plasmids were characterized in recipient strains by their profiles and molecular weights using agarose gel electrophoresis, by their antimicrobial resistance patterns and by replicon typing using a series of dna probes specific for the genes controlling their syst ...19938405151
characterization of the ferrous iron uptake system of escherichia coli.escherichia coli has an iron(ii) transport system (feo) which may make an important contribution to the iron supply of the cell under anaerobic conditions. cloning and sequencing of the iron(ii) transport genes revealed an open reading frame (feoa) possibly coding for a small protein with 75 amino acids and a membrane protein with 773 amino acids (feob). the upstream region of feoab contained a binding site for the regulatory protein fur, which acts with iron(ii) as a corepressor in all known ir ...19938407793
molecular cloning, nucleotide sequencing, and affinity labeling of bovine liver udp-glucose pyrophosphorylase.a bovine liver cdna encoding udp-glucose pyrophosphorylase [ec 2.7.7.9], which catalyzes the reversible uridylyl transfer between glucose 1-phosphate and mgutp, has been cloned by the use of oligonucleotide probes synthesized on the basis of partial amino acid sequences of the enzyme. the cdna clone contained a 1,689 base-pair insert including the complete message for the subunit polypeptide (508 amino acid residues) of the octameric enzyme. the bovine liver enzyme shows significant sequence sim ...19938407878
prevalence and some properties of verotoxin (shiga-like toxin)-producing escherichia coli in seven different species of healthy domestic animals.fecal samples from 720 healthy, domestic animals representing seven different species (cattle, sheep, goats, pigs, chickens, dogs, and cats) were investigated for verotoxin (vt [shiga-like toxin])-producing escherichia coli (vtec). vtec were isolated from 208 animals (28.9%), most frequently from sheep (66.6% vtec carriers), goats (56.1%), and cattle (21.1%). vtec were isolated less frequently from pigs (7.5%), cats (13.8%), and dogs (4.8%) and were not found in chickens (< 0.7%). forty-one diff ...19938408571
lipopolysaccharide interaction with s2 subunit of pertussis toxin.using radioiodinated, photoactivable, reducible cross-linker conjugated bacterial endotoxic lipopolysaccharide (125i-asd-lps), we have demonstrated that lps selectively binds to the s2 subunit of pertussis toxin (pt). since lps also interacts with the s2 subunit of the b-oligomer of the toxin, the binding of lps to pt is not a-protomer (s1 subunit) dependent. the binding can be inhibited with native underivatized lps and with purified lipid a, suggesting that the binding is mediated through the ...19938419348
expression of wild-type and mutant bovine pancreatic ribonuclease a in escherichia coli.wild-type ribonuclease a and five mutants thereof have been expressed in escherichia coli as fusion proteins by using a t7 expression system. the five mutants are c[65-72]s, c[40-95]s, c[58-110]s, c[26-84]s, and k41g. the expressed fusion protein formed inclusion bodies which were then cleaved by factor xa. the cleaved ribonuclease a was isolated as unfolded (sulfonated), soluble protein which was subsequently folded. this expression system can be used to produce mutants of ribonuclease a in yie ...19938421696
comparative analysis of using mtt and xtt in colorimetric assays for quantitating bovine neutrophil bactericidal activity.two different tetrazolium compounds were compared for use in a colorimetric assay for quantitating bovine neutrophil bactericidal activity against staphylococcus aureus, escherichia coli, listeria monocytogenes, and brucella abortus. the tetrazolium compounds tested included 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide (mtt) and sodium 3,3'-[1[(phenylamino)carbonyl]-3,4- tetrazolium]-bis(4-methoxy-6-nitro) benzene sulfonic acid hydrate (xtt). the mtt and xtt colorimetric bacteric ...19938423367
porphobilinogen synthase from escherichia coli is a zn(ii) metalloenzyme stimulated by mg(ii).porphobilinogen synthase (pbgs) is essential to all life forms; in mammals it is definitively established that zn(ii) is required for activity. the literature regarding the metal requirement for pbgs in other animals, plants, and bacteria neither establishes nor disproves a zn(ii) requirement. we have characterized escherichia coli pbgs and found it to be remarkably similar to bovine pbgs. the similarities include a requirement for zn(ii), inhibition by 1,10-phenanthroline, an exceptional therma ...19938424649
cytokine production during endotoxin-induced mastitis in lactating dairy cows.the role of interleukin-1 (il-1), interleukin-6 (il-6), and tumor necrosis factor alpha during endotoxin-induced mastitis in cows was characterized. six cows had 10 micrograms of escherichia coli lipopolysaccharide infused into 1 mammary gland. three other cows served as nontreated controls. within 1.5 to 2.5 hours after infusion, endotoxin caused obvious edema of the mammary gland and increased serum albumin concentration in milk of infused glands 6 times. milk somatic cell count began to incre ...19938427476
functional organization of microtubule-associated protein tau. identification of regions which affect microtubule growth, nucleation, and bundle formation in vitro.tau protein is a microtubule-associated protein that is almost exclusively expressed in the brain and is enriched in the axon. determination of tau's sequence has revealed three to four tandem repeats that have been shown to constitute the microtubule binding site. in order to study the functional organization of tau, we prepared a series of truncated tau fragments using an escherichia coli expression system. we assayed each fragment's activity in promoting growth of microtubules and in nucleati ...19938429017
two light-transducing membrane proteins: bacteriorhodopsin and the mammalian rhodopsin.site-directed mutagenesis has provided insight into the mechanisms of action of bacteriorhodopsin and rhodopsin. these studies are summarized here.19938433978
interleukin-1 beta-specific partial agonists defined by site-directed mutagenesis studies.monocyte-derived interleukin 1 (il-1) mediates a wide range of biological effects including destruction of the cartilage matrix in articular diseases such as rheumatoid and osteoarthritis. to elucidate further the relationships between protein structure and biological activities, we have analyzed the sequence of several il-1 polypeptides using the algorithm of parker, the hydrophobic cluster analysis method and published structural data. this led us to identify several residues that seemed to be ...19938436117
vero cytotoxin-producing escherichia coli in a herd of dairy cattle. 19938438553
aminopeptidases: structure and function.aminopeptidases catalyze the cleavage of amino acids from the amino terminus of protein or peptide substrates. they are widely distributed throughout the animal and plant kingdoms and are found in many subcellular organelles, in cytoplasm, and as membrane components. several aminopeptidases perform essential cellular functions. many, but not all, of these peptidases are zinc metalloenzymes and are inhibited by the transition-state analog bestatin. some are monomeric, and others are assemblies of ...19938440407
vitamin e as an adjuvant in an escherichia coli j5 vaccine.vitamin e was tested as an adjuvant in an escherichia coli (o111:b4) j5 vaccine. twenty cows were assigned to five groups of 4 cows. cows in four groups were vaccinated with an e. coli j5 bacterin containing 5 ml of 10(9) boiled cells/ml. vaccinations were at drying off, 30 d after drying off, and within 48 h after calving. vaccine adjuvants differed among groups. the four treatment adjuvants were 5 ml of freund's incomplete adjuvant, 5 ml of vitamin e, 2.5 ml of freund's plus 2.5 ml of vitamin ...19938445093
serum concentrations of copper, iron, and zinc during escherichia coli-induced mastitis.six holstein cows were intracisternally challenged with 50 cfu of escherichia coli to induce acute mastitis. clinical status, milk concentrations of bacteria, and serum albumin concentration were determined to monitor the progress and severity of infection for 72 h after bacterial challenge. blood samples were also collected throughout infection to determine serum concentrations of zn, fe, and cu. experimental e. coli mastitis resulted in mean serum concentrations of zn, fe, and cu of 28, 35, an ...19938445094
endotoxemia in dairy cattle: role of eicosanoids in reticulorumen stasis.the role of arachidonic acid metabolites in the forestomach stasis induced by escherichia coli endotoxin was evaluated. six adult holstein cows received saline solution; endotoxin at 1, 10, and 100 ng/kg of body weight; flunixin meglumine at 1.1 mg/kg of body weight; and flunixin meglumine at 1.1 mg/kg plus endotoxin at 100 ng/kg. the frequency of reticulorumen contractions, mental attitude, body temperature, respiratory rate, heart rate, and plasma concentration of prostaglandin e2, prostacycli ...19938445095
detection of bacterial antigens in milk samples from clinical cases of bovine mastitis in which culture is negative.elisas to detect antigens against staphylococcus aureus, escherichia coli, streptococcus agalactiae, streptococcus dysgalactiae and streptococcus uberis were developed and used on whey samples from quarter milk samples from cases of clinical mastitis in which no bacterial pathogen had been isolated by standard culture techniques. antigens against one or other of the bacteria listed above were detected in 68 per cent of 84 samples. fifty-one per cent of the 84 samples contained antigens to e coli ...19938451811
nucleotide sequence and over-expression of morphine dehydrogenase, a plasmid-encoded gene from pseudomonas putida m10.pseudomonas putida m10 was originally isolated from factory waste liquors by selection for growth on morphine. the nadp(+)-dependent morphine dehydrogenase that initiates morphine catabolism is encoded by a large plasmid of 165 kb. treatment of p. putida m10 with ethidium bromide led to the isolation of a putative plasmid-free strain that was incapable of growth on morphine. the structural gene for morphine dehydrogenase, mora, has been located on the plasmid by oligonucleotide hybridization, by ...19938452544
characterization of the mouse autoantigen la (ss-b). identification of conserved rna-binding motifs, a putative atp binding site and reactivity of recombinant protein with poly(u) and human autoantibodies.to facilitate the study of autoimmunity to the nuclear ag la (ss-b) we have isolated and characterized cdna encoding the mouse la (ss-b) protein. mouse la (ss-b) protein has 76.7% identity to both human and bovine la (ss-b) proteins and the previously recognized rnp-binding motifs were noted to be highly conserved across the three species. examination of the primary sequence of human and bovine la (ss-b) newly identifies the site of a potential atp-binding motif g/axxxxgk which is preserved in m ...19938454877
the eukaryotic host factor that activates exoenzyme s of pseudomonas aeruginosa is a member of the 14-3-3 protein family.exoenzyme s (exos), which has been implicated as a virulence factor of pseudomonas aeruginosa, catalyzes transfer of the adp-ribose moiety of nad+ to many eukaryotic cellular proteins. its preferred substrates include ras and several other 21- to 25-kda gtp-binding proteins. exos absolutely requires a ubiquitous eukaryotic protein factor, termed fas (factor activating exos), for enzymatic activity. here we describe the cloning and expression of a gene encoding fas from a bovine brain cdna librar ...19938460141
further characterization of pasteurella haemolytica-like bacteria isolated from swine enteritis.dna-dna hybridization studies were conducted on six pasteurella haemolytica-like (phl) organisms recovered from cases of swine enteritis. chromosomal-enriched fractions of phl organisms served as the source of dna for southern blots or as whole-chromosomal dna probes. under stringent hybridization conditions, chromosomal dna probes of a prototype phl (strain 6213a) organism distinguished other phl organisms from pasteurella haemolytica types a1 and t3, pasteurella multiocida types a:1 and a:3, e ...19938460470
toxicity of bordetella avium beta-cystathionase toward mc3t3-e1 osteogenic cells.bordetella avium is the etiological agent of an upper respiratory disease in birds which, symptomatically and pathologically, resembles bordetellosis in humans. studies of the virulence of this organism revealed a novel cytotoxic protein, designated osteotoxin, that was lethal for mc3t3-e1 osteogenic cells, fetal bovine trabecular cells, umr106-01(bsp) rat osteosarcoma cells, and embryonic bovine tracheal cells. the osteotoxin lacked dermonecrotic toxin activity, exhibited no cross-reactivity wi ...19938463265
the binding site for the beta gamma subunits of heterotrimeric g proteins on the beta-adrenergic receptor kinase.the beta gamma subunits of heterotrimeric g proteins play important roles in regulating receptor-stimulated signal transduction processes. recently appreciated among these is their role in the signaling events that lead to the phosphorylation and subsequent desensitization of muscarinic cholinergic (haga, k., and haga, t. (1992) j. biol. chem. 267, 2222-2227) and beta-adrenergic (pitcher, j. a., inglese, j., higgins, j. b., arriza, j. l., casey, p. j., kim, c., benovic, j. l., kwatra, m. m., car ...19938463335
effects of intramammary endotoxin infusion on milking-induced oxytocin release.one overt sign of clinical coliform mastitis in dairy cows is the failure to eject milk normally or to "milk out" the udder. the effect, if any, of coliform mastitis on oxytocin release is unknown. therefore, the objective of this study was to determine the effect of endotoxin mastitis on milking-induced release of oxytocin in lactating cows. fifteen multiparous pregnant lactating holstein cows were divided into three groups of 5 cows each. cows in group 1 served as controls and received an intr ...19938463485
cocatalytic zinc motifs in enzyme catalysis.cocatalytic zinc binding sites are characteristic of enzyme molecules which contain two or more zinc and/or other metal atoms. in each site an aspartate, glutamate, or histidine residue simultaneously binds to two zinc atoms or a zinc and a different metal atom. in the resultant amino acid bridge, two of the cocatalytic metal atoms bind to the same amino acid. consequently the participating metal atoms are in close proximity and function as a catalytic unit, typical of this motif. in these funct ...19938464881
soluble antigen profoundly reduces memory b-cell numbers even when given after challenge immunization.the splenic b-cell repertoire of unimmunized c57bl/6 mice can be examined for anti-(4-hydroxy-3-nitrophenyl)acetyl (np) b cells of relatively high affinity by using a dual strategy. first, limiting numbers of splenocytes are polyclonally activated by escherichia coli lipopolysaccharide and a mixture of interleukins 2, 4, and 5 in the presence of 3t3 filler cells, thus ensuring that many b-cell clones switch to igg1 antibody production. second, an enzyme-linked immunosorbent assay is geared to re ...19938464928
bacterial agents detected in a 10-year study of bovine abortions and stillbirths.in a 10-year survey started in 1980, specimens from 8,995 bovine abortions and stillbirths were submitted to the south dakota animal disease research and diagnostic laboratory. of these, 8,962 were suitable for some type of examination. bacteria were determined to be the cause of 1,299 (14.49%). the 5 bacteria most commonly associated with bovine abortion or stillbirth were actinomyces pyogenes, 378 (4.22%); bacillus spp., 321 (3.58%); listeria spp., 121 (1.35%); escherichia coli, 98 (1.09%); an ...19938466983
[biosynthesis of bovine growth hormone in escherichia coli dh1 cells and its purification on a pilot scale].the biosynthesis of the bovine growth hormone (bgh) in e. coli dh1 cells containing the plasmid pbgh(1-119)ptrp was studied. it was found that bgh accumulated in the cytoplasm of bacterial cells as optically dense granules that can be isolated by low-speed centrifugation. a fraction of purified protein granules was used for further purification of bgh. a purified bgh preparation contained two polypeptides with molecular weights of 18,000 and 22,000 d. the state of plasmid was investigated during ...19938475017
comparison of several new chromogenic galactosides as substrates for various beta-d-galactosidases.the kinetic characteristics of beta-galactosidases from bovine liver and testes, escherichia coli, aspergillus niger and jack bean were studied using five newly-developed colorimetric substrates. all the chromophores released by enzyme hydrolysis had high extinction coefficients in the visible region of the spectrum. varying amounts of substrate inhibition were found with each of these substrates (vbztm-gal, vlm-gal, vlpr-gal, vqm-gal and vqpr-gal), but this was not a significant problem if the ...19938476929
sandwich enzyme immunoassay for rat retinol-binding protein using antibody against recombinant antigen and its application.the development of a sandwich enzyme immunoassay for rat retinol-binding protein using molecular biological techniques was described. rat retinol-binding protein gene cloned by the pcr method was expressed by a fusion vector pezz18 in escherichia coli strain hb101. a recombinant retinol-binding protein fused with igg-binding domain zz of protein a was purified with igg-sepharose. antibody against the recombinant protein was found to be specific to rat retinol-binding protein in plasma by immunob ...19938484958
steroid induced single strand breaks in dna mediated by active oxygen species and its biological consequences.a mutagenic steroidal derivative (3 beta-acetoxy-5 alpha-cholestano[6 alpha,5-d']1'-3'oxathiolane-2' thione) structurally related to cholesterol caused strand scission and induced nicks in calf thymus, supercoiled pbr322 and single stranded m13 mp8 phage dnas. s1 nuclease hydrolysis, reaction with pbr322 and m13 phage dna as well as treatment of e. coil mutant strains and phage was used to evaluate the effect of test steroid on the dna molecule. the strand scission/nicking of dna by the test ste ...19938485466
immunodiagnosis of group-a streptococci by latex agglutination assays with monoclonal or monospecific polyvalent antibodies.seven clones of murine monoclonal antibodies specific for group-a streptococci were generated. all of them were of igm isotypes and recognized trypsinized as well as nontrypsinized group-a streptococci and polysaccharide. these were devoid of reactivity with streptococci-b, -c, -g and staphylococcus aureus. polyclonal antibodies against group-a polysaccharide (aps) were also raised in rabbits by linking aps to bovine serum albumin, and rendered monospecific by adsorption. latex agglutination ass ...19938486405
identity elements of trna(trp). identification and evolutionary conservation.in this study, the varying reactivities of bacillus subtilis tryptophanyl-trna synthetase toward prokaryotic, eukaryotic, and halophile trnas were employed to define the potential identity elements on trna(trp). on this basis mutagenesis was performed to obtain, through in vivo heterologous expression in escherichia coli and in vitro transcription with t7 rna polymerase, mutant b. subtilis trna(trp) for comparison with the wild-type. these comparisons served to establish g73 and the anticodon as ...19938486627
costs of clinical mastitis and mastitis prevention in dairy herds.a stratified random sample of 50 ohio dairy herds, monitored for 1 year between march 1988 and may 1989, was used to estimate the component costs of clinical mastitis per cow-year overall and by organism, the component costs of an episode of clinical mastitis overall and by organism, and the incidence of clinical mastitis by organism. each herd was visited monthly by a veterinarian who conducted on-farm interviews and completed standardized data-collection forms designed to elicit economic infor ...19938496076
production of biologically active light chain of tetanus toxin in escherichia coli. evidence for the importance of the c-terminal 16 amino acids for full biological activity.the activity of the light (l) chain of tetanus toxin, and of mutants constructed by site-directed mutagenesis, was studied by expression and purification of the proteins from e. coli. wild-type recombinant l chain (ptet87) was active in the inhibition of exocytosis from cultured bovine adrenal chromaffin cells, although at a level 5-15% of that of l chain purified from tetanus toxin. l chain mutants which terminated at leu-438 (ptet89), or which contained a cys-to-ser mutation at residue 439 (pt ...19938500613
cerebrospinal fluid composition of cattle with endotoxin-induced mastitis treated with isotonic (0.9%) or hypertonic (7.5%) sodium chloride.this study examined the safety of intravenous hypertonic saline in cattle with experimental gram-negative endotoxemia. cerebrospinal fluid (csf) composition was examined in five control cows and eight treated cows 24 hours after the intramammary infusion of 1 mg of endotoxin. four of the endotoxin challenged cows were treated intravenously with isotonic (0.9%) sodium chloride and four cows were treated intravenously with hypertonic (7.5%) sodium chloride. decreased csf osmolality, and sodium and ...19938501700
expression of bovine seminal ribonuclease in escherichia coli.bovine seminal rnaase (bs-rnaase), an unusually dimeric member of the pancreatic-like ribonuclease superfamily, is also a multifunctional biological effector, with antitumor, immunosuppressive, and antispermatogenic activities. we report here the cloning of a semi-synthetic cdna coding for the protein subunit chain, its expression with a t7 expression system in escherichia coli inclusion bodies, the dimerization of correctly reoxidized monomeric protein, followed by the purification in high yiel ...19938503902
cloning and functional expression of dendrotoxin k from black mamba, a k+ channel blocker.mamba dendrotoxins, 7k m(r) polypeptides with three disulfide bonds, selectively inhibit certain fast-activating, voltage-sensitive neuronal k+ channels and have been instrumental in their identification, localization, and purification. however, derivatives with more refined specificity are essential to define the structural and functional properties of the multiple subtypes known to reside in the nervous system. hence, utilizing a constructed cdna library from the venom glands of the black mamb ...19938504088
characterization of the foot-and-mouth disease virus 3c protease expressed in escherichia coli.we have constructed a clone encoding the foot-and-mouth disease virus (fmdv) 3c protease gene (p3c) using the polymerase chain reaction. the construct was engineered to contain initiation and termination codons and cloned into a plasmid under the control of the bacteriophage t7 promoter. the p3c gene was expressed both in an in vitro transcription-translation system and in vivo in an escherichia coli system containing an inducible t7 rna polymerase gene. in both systems the expressed products we ...19938212567
hemostasis in cows with endotoxin-induced mastitis.hemostasis was evaluated in cows with experimentally induced endotoxemia and mastitis, caused by intramammary infusion of endotoxin (1 mg) derived from escherichia coli. hemostatic tests included prothrombin time; activated partial thromboplastin time; thrombin time; fibrinogen, fibrin(ogen) degradation products, and platelet concentrations; and antithrombin-iii and plasminogen activities. significant alterations were observed in the mean values of most analytes (prothrombin time was increased; ...19938214888
substrate specificity of the escherichia coli endonuclease iii: excision of thymine- and cytosine-derived lesions in dna produced by radiation-generated free radicals.the excision of modified bases from dna by escherichia coli endonuclease iii was investigated. modified bases were produced in dna by exposure of dilute buffered solutions of dna to ionizing radiation under oxic or anoxic conditions. the technique of gas chromatography/mass spectrometry (gc/ms) was used to identify and quantify 16 pyrimidine- and purine-derived dna lesions. dna substrates were incubated either with the native enzyme or with the heat-inactivated enzyme. subsequently, dna was prec ...19938218289
cloning, sequencing and expression of a pasteurella haemolytica a1 gene encoding a purk-like protein.a membrane protein antigen of pasteurella haemolytica a1 encoded on the recombinant plasmid pyfc13 is isolated and characterized. nucleotide sequence analysis of the insert dna in pyfc13 identified the gene mpa1, which codes a protein of approximately 45 kda without signal sequence. the deduced amino acids from the dna sequence are homologous to bacillus subtilis purk by 29.4%; to schizosaccharomyces pombe pur6 by 29.34%, to saccharomyces cerevisiae pur6 by 25.867%; and to e. coli purk by 25.223 ...19938219279
escherichia coli producing cnf1 and cnf2 cytotoxins in animals with different disorders.two dna probes were used for the detection of cnf1- and cnf2-positive e coli strains in a collection of 553 e coli isolates from cattle, sheep, goats, pigs, horses, dogs, cats and poultry. cnf-positive e coli were frequently associated with septicaemia in cattle, dogs, and cats, with diarrhoea in calves, cats and dogs, and with abortion in bovine and porcine species. cnf2-positive strains were observed among adult healthy cattle. they were also found in cases of pneumonia, metritis, mastitis in ...19938220498
isolation and characterization of the rickettsia prowazekii gene encoding the flavoprotein subunit of succinate dehydrogenase.the gene (sdha) coding for the flavoprotein subunit (sdha) of succinate dehydrogenase of the obligate intracellular parasitic bacterium, rickettsia prowazekii, has been isolated using an oligodeoxyribonucleotide probe to the conserved flavin adenine dinucleotide (fad)-binding region of characterized flavoproteins. nucleotide (nt) sequence analysis revealed an open reading frame (orf) of 1791 bp capable of encoding a protein of 596 amino acids (aa) with a deduced m(r) of 65,444. the deduced aa se ...19938224887
atp hydrolysis is not stoichiometrically linked with proteolysis in the atp-dependent protease la from escherichia coli.protein degradation in escherichia coli involves the atp-dependent serine protease la. protease la is a homotetramer with one proteolytic and one atp binding site per monomer. its proteolytic activity has been shown to be highly increased by simultaneous hydrolysis of atp, which is essential for the degradation of protein substrates by this enzyme. we have cloned and purified a proteolytically inactive la mutant, in which the catalytically active serine residue at position 679 was replaced by al ...19938226758
bovine acute mastitis: effects of intravenous sodium salicylate on endotoxin-induced intramammary inflammation.effects of the nonsteroidal antiinflammatory agent sodium salicylate on endotoxin-induced mastitis were evaluated in lactating cows. escherichia coli endotoxin was administered to a mammary quarter 1 h after initiation of a 12-h i.v. infusion of sodium salicylate. milk scc, bsa concentrations in milk, mammary inflammation, rectal temperature, appetite, milk production, and plasma and lymph pgf2 alpha were monitored. gross mammary inflammation was not reduced by salicylate infusion, nor did sodiu ...19938227658
forms of lactoferrin: their antibacterial effect on enterotoxigenic escherichia coli.the antibacterial effects of various forms of lactoferrin on enterotoxigenic strains of escherichia coli were tested in vitro using a microassay for bacterial growth. native and apo-lactoferrin exhibited variable activity against 19 strains, whereas holo-lactoferrin had no effect. at a concentration of .2 mg/ml of apo-lactoferrin, strains could be distinguished as either sensitive or resistant to inhibition. zinc-saturated lactoferrin was as inhibitory as apo-lactoferrin when sensitive and resis ...19938227660
characterisation of verocytotoxin-producing escherichia coli isolated from pigs and cattle in northern italy. 19938236671
comparative efficacy of flunixin, ketoprofen, and ketorolac for treating endotoxemic neonatal calves.saline (0.9% nacl) solution or 1 of 3 nonsteroidal anti-inflammatory drugs (nsaid) was administered i.v. to 5 neonatal calves 15 minutes after the start of a 3-hour i.v. infusion of escherichia coli lipopolysaccharide (lps; 2 micrograms/kg/h). four additional calves were given a 3-hour i.v. infusion of saline solution alone. clinical attitude, mean arterial blood pressure, pcv, wbc, and plasma lactate, glucose, and eicosanoid concentrations (thromboxane b2, 6-keto-pgf1 alpha) were monitored for ...19938239142
a cdna derived from pig bone marrow cells predicts a sequence identical to the intestinal antibacterial peptide pr-39.we have recently shown that a group of antimicrobial peptides of bovine neutrophils share highly identical pro-sequences. in this paper we report the cdna sequence of a 172 amino acid residue pig myeloid protein showing a similar pro-sequence of 101 residues. the carboxyl-moiety of the predicted protein is identical to the mature form of the proline- and arginine-rich antibacterial peptide named pr-39, isolated from pig intestine.19938250863
neonatal septicemia in calves: 25 cases (1985-1990).historical, physical, and clinicopathologic findings in 25 septicemic calves were examined to further characterize the clinical features of naturally induced bovine neonatal septicemia. owners often reported single organ disease, but physical examination revealed multiple organ disease in more than half the calves. a third of the calves were admitted as representative of a herd problem. laboratory findings were variable, but commonly included changes in the differential wbc count and plasma fibr ...19938253629
[physiological function of the gastrointestinal tract and pathophysiological changes in neonatal diarrhea of calves].firstly, the basic principles of absorption and secretion in the intestine of healthy animals are described. the etiology and the pathophysiologic mechanisms of neonatal diarrhea in the calf due to e. coli and rota-/coronavirus are discussed. enterotoxins of e. coli stimulate primarily the secretion of chloride (and thereby water) in the small intestine without damaging the intestinal mucosa. the sodium-dependent transport systems for the absorption of glucose and amino acids remain intact. in c ...19938261915
multiresistant strains of escherichia coli isolated from the rumen of young calves.five multiresistant strains of escherichia coli were isolated from the rumen fluid of young calves. resistance to tetracycline and ampicillin was found to be associated with the transfer of a 6.4 kbp plasmid present in two investigated strains.19938262445
protection against chloroethylnitrosourea cytotoxicity by eukaryotic 3-methyladenine dna glycosylase.a eukaryotic 3-methyladenine dna glycosylase gene, the saccharomyces cerevisiae mag gene, was shown to prevent n-(2-chloroethyl)-n-nitrosourea toxicity. disruption of the mag gene by insertion of the ura3 gene increased the sensitivity of s. cerevisiae cells to n-(2-chloroethyl)-n-nitrosourea, and the expression of mag in glycosylase-deficient escherichia coli cells protected against the cytotoxic effects of n-(2-chloroethyl)-n-nitrosourea. extracts of e. coli cells that contain and express the ...19938265637
[infectious diarrhea of calves: therapeutic and preventive possibilities based on etiological, pathophysiological and immunological data].in this article the current knowledge on the development mechanisms of bacterial, viral and cryptosporidial neonatal calf diarrhoea are briefly reviewed as basis for an efficacious prophylaxis strategy. hygienic measures will prevent the infection of the calf before colostrum intake and will diminish the infection pressure during the first weeks of life. moreover, local intestinal immunity will be provided by early administration of immune colostrum for the prevention of e.coli diarrhoea and pro ...19938266306
cattle as a possible source of verocytotoxin-producing escherichia coli o157 infections in man.in may-june 1992 cases of infection with verocytotoxin-producing (vt+) escherichia coli o157 in south yorkshire could have been associated with prior consumption of beef from a local abattoir. during investigation of the abattoir, bovine rectal swabs and samples of meat and surface swabs from beef carcasses were examined for e. coli o157, isolates of which were tested for toxigenicity, plasmid content and phage type. e. coli o157 was isolated from 84 (4%) of 2103 bovine rectal swabs; of these 84 ...19938270004
severity of experimental escherichia coli mastitis in ketonemic and nonketonemic dairy cows.the severity of experimental escherichia coli mastitis in relation to in vitro chemotaxis of polymorphonuclear leukocytes was investigated in cows during negative energy balance. the negative energy balance was induced by feed restriction. cows were classified into two groups, ketonemic and nonketonemic, based on the beta-hydroxybutyrate concentration in the peripheral blood at the moment of inoculation. bacterial growth in the inoculated quarter was used as a parameter to indicate the severity ...19938270685
effects of recombinant human cytokines on mitogen-induced bovine peripheral blood mononuclear cell proliferation.the effects of interleukin 1 alpha (il-1 alpha), il-1 beta, il-2, il-3, il-4, il-5, il-6, il-7, il-8, and insulin growth factor-1 (igf-1) on proliferation of mitogen-stimulated bovine peripheral blood mononuclear cells (pbmc) were determined. four concentrations of each cytokine were incubated 48 or 96 h with pbmc alone or with pbmc and three concentrations of three different mitogens. the mitogens included concanavalin a (con a) phytohemagglutinin (pha), and escherichia coli 055:b5 lipopolysacc ...19938142606
vasoactive intestinal peptide and helodermin inhibit phospholipase a2 activity in vitro.we recently reported that the widely distributed neuropeptide vasoactive intestinal peptide (vip) reduces inflammatory lung injury due to a variety of agents and inhibits the associated generation of cyclo-oxygenase and lipoxygenase products. we therefore investigated whether vip may inhibit phospholipase a2 activity, thus reducing the release of arachidonic acid, the common precursor of all eicosanoids. vip dose-dependently inhibited pla2 of porcine pancreas and of naja naja venom, as assessed ...19938278623
sugar-binding sites with specificity for glucosamine in the guinea pig middle ear mucosa.glucosamine-binding sites were detected in lowicryl k4m-embedded guinea pig middle ear mucosa by electron microscopy, using glucosaminyl bovine serum albumin. incubation of ultrathin tissue sections with gold-labeled glucosaminyl bovine serum albumin (glcn/bsa/gold) resulted in binding mainly on cilia, microvilli, rough endoplasmic reticulum and nuclei. the sugar binding was not inhibited after ultrathin sections had been digested with trypsin or neuraminidase. various carbohydrates and glycocon ...19938286107
overproduction of the toxic protein, bovine pancreatic dnasei, in escherichia coli using a tightly controlled t7-promoter-based vector.a synthetic gene coding for bovine pancreatic dnasei has been cloned under the control of a t7 promoter present on the plasmid pet11. this construct yields a stable escherichia coli transformant only when transcription from this promoter is tightly controlled. production of recombinant dnasei (rednasei) is achieved by infection of the cells with a mutant lambda phage, ce6, which carries the gene encoding t7 rna polymerase. induced bacterial cultures yield in excess of 2 mg per litre of rednasei ...19938294027
possible link between cattle and e coli o157 infection in a human. 19938296437
growth of lactobacilli, staphylococcus aureus and escherichia coli in normal and mastitic milk and whey.the growth of three lactobacilli (lactobacillus acidophilus, l. bulgaricus and l. casei), staphylococcus aureus and escherichia coli was followed in normal and mastitic milk and whey using the standard plate count method. l. acidophilus, l. bulgaricus 6032 and l. casei 6028 grew well in normal milk, but had decreased growth in mastitic milk if not pre-adapted in mastitic whey. s. aureus 26003 and e. coli 44102 showed enhanced growth in mastitic milk as compared with their growth in normal milk. ...19938296441
characterization of the nr1, nr2a, and nr2c receptor proteins.n-methyl-d-aspartate (nmda) receptor subunits were characterized with seven polyclonal antibodies. the antibodies were directed against nr1-a, nr2a-n1, and nr2c-n1, representing n-terminal sequences of the nr1, nr2a, and nr2c subunits, and against nr1-e, nr2a-c1, and nr2c-c1, derived from c-terminal sequences of these subunits. the anti-nr1-d antibody was raised against the putative internal loop of nr1. a size of 118 kda was found in sodium dodecyl sulfate-polyacrylamide gel electrophoresis for ...19938298456
the expression of bovine microsomal cytochrome b5 in escherichia coli and a study of the solution structure and stability of variant proteins.the dna sequence of bovine microsomal cytochrome b5 has been amplified from a liver cdna library using a polymerase chain reaction. the amplified cdna when cloned into plasmids that support the high-level production of cytochrome b5 in e.coli leads to protein overexpression and results in cell colonies bearing a strong red colouration. using cassette mutagenesis, truncated versions of the cytochrome b5 cdna have been made that encode the first 90 amino acid residues (ala1-lys90), the first 104 a ...19938309945
neutral red assay for measurement of quantitative vero cell cytotoxicity.a neutral red assay involving vero cells was used to quantitate the cytotoxic activity of verotoxins (vt) produced by escherichia coli and to investigate changes in titer caused by altering the composition of the cell culture medium. three variations on medium 199 were investigated: one involved supplementing the medium with 5% fetal bovine serum (fbs), a second was the use of serum-free (sf) medium that contained 5% bovine serum albumin and 5 mug of fibronectin per ml, and the third involved th ...199316348976
spontaneous uterine infections are associated with elevated prostaglandin f(2)alpha metabolite concentrations in postpartum dairy cows.postpartum holstein (n=21) and jersey (n=4) cows were used to determine if uterine infections are associated with elevated plasma concentrations of 13,14-dihydro-15-keto-prostaglandin f(2)alpha (pgfm). based upon clinical examinations and bacterial content of intrauterine fluid samples, cows detected with uterine infections between 21 and 28 d post partum were used (infected; n=14). these cows were matched with herdmates that were free of infection (control; n=11). beginning on the day the cows ...199416727399
transfer of multiple drug resistance plasmids between bacteria of diverse origins in natural microenvironments.plasmids harboring multiple antimicrobial-resistance determinants (r plasmids) were transferred in simulated natural microenvironments from various bacterial pathogens of human, animal, or fish origin to susceptible strains isolated from a different ecological niche. r plasmids in a strain of the human pathogen vibrio cholerae o1 e1 tor and a bovine escherichia coli strain were conjugated to a susceptible strain of the fish pathogenic bacterium aeromonas salmonicida subsp. salmonicida in marine ...199411865872
studies on the proton-translocating nadh:ubiquinone oxidoreductases of mitochondria and escherichia coli using the inhibitor 1,10-phenanthroline.mitochondrial nadh:ubiquinone oxidoreductase (complex i) is uncompetitively inhibited by 1,10-phenanthroline (op). epr spectroscopy of submitochondrial particles indicates that op, similarly to rotenone, inhibits electron transfer between the fe-s clusters of complex i and the ubiquinone pool. the proton-translocating nadh dehydrogenase (ndh1) of e. coli is more sensitive to op than is ndh1 of paracoccus. epr spectroscopy of membranous e. coli ndh1 shows that two slow- and one fast-relaxing fe-s ...19948313963
metabolic, endocrine and haematological responses to intravenous e. coli endotoxin administration in 1-week-old calves.responses to i.v. injected e. coli endotoxin (e), followed by saline infusion, as compared with saline infusion alone, were studied for 24 h in 1-week-old calves. after administration of e, respiratory rate (rr), heart rate (hr), rectal temperature (rt), serum iron, insulin, (i), cortisol and tumor necrosis factor-alpha, transiently, and urea, continuously, increased. isoleucine and leucine became elevated at 24 h, whereas white-blood-cell number, free fatty acids (ffa) and triglycerides (tg) in ...19948831269
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