maple syrup urine disease: domain structure, mutations and exon skipping in the dihydrolipoyl transacylase (e2) component of the branched-chain alpha-keto acid dehydrogenase complex.maple syrup urine disease (msud) is an autosomal recessive disorder in the oxidative decarboxylation of the branched-chain alpha-keto acids derived from leucine, isoleucine and valine. the enzyme deficient in msud, the branched-chain alpha-keto acid dehydrogenase (bckad) complex, is a mitochondrial multienzyme complex consisting of at least six distinct subunits. msud is genetically heterogeneous as manifested by lesions in different subunits of the bckad complex among unrelated patients. to app ...19911943690
effect of vaccination with the r mutant escherichia coli (j5) antigen on morbidity and mortality of dairy calves.a prospective cohort study was undertaken to determine the efficacy of escherichia coli 0111:b4 (j5) vaccination in dairy calves. calves on 2 units were vaccinated when they were 2 to 3 days old and 2 weeks later with the j5 antigen or they were left unvaccinated, and were observed during the first 60 days of age for morbidity and mortality. events recorded were death, the first case of illness, the first sign of a respiratory tract condition, the first sign of diarrhea, and the first treatment. ...19911952340
antibodies to iron-regulated outer membrane proteins of coliform bacteria isolated from bovine intramammary infections.expression of iron-regulated outer membrane proteins (omp) by escherichia coli and klebsiella pneumoniae initially isolated from bovine intramammary infections (imi) was investigated. additionally, the presence of antibodies in bovine serum and mammary secretion directed against the iron-regulated omp was examined. outer membrane proteins were separated by sodium-dodecyl polyacrylamide electrophoresis. detection of immunoglobulin g directed against omp was by immunoblotting. all gram-negative ba ...19911866891
isolation and characterization of a saccharomyces cerevisiae mutant disrupted for the succinate dehydrogenase flavoprotein subunit.a partial genomic clone of the flavoprotein subunit of the mitochondrial enzyme, succinate dehydrogenase (ec from saccharomyces cerevisiae has been isolated. the partial clone was used to construct, by targeted gene disruption, a yeast mutant with a defective flavoprotein subunit gene. submitochondrial membranes from the mutant are defective in activities requiring a functional succinate dehydrogenase but not in other respiratory chain activities. in addition, the mutant contains signi ...19911939170
nine dna probes for detection of toxin and adhesin genes in escherichia coli isolated from diarrhoeal disease in animals.dna gene probes specific for genes encoding heat labile enterotoxin (lti), heat stable enterotoxins (stia, stii), vero cytotoxins (vt1, vt2), and adhesins k88 (f4), k99(f5), f41 and 987p(f6) were used to examine 873 isolates of e. coli from cases of diarrhoea (680 from pigs, 187 from cattle and six from sheep). a total of 188 were toxin gene positive and of these 84 belonged to the classical etec serogroups. of the other 104 toxin gene positive strains, 80 hybridized with the vt2 probe of which ...19901978952
[isolation of vero toxin-producing escherichia coli (vtec) from imported meats].one hundred and four samples of various imported meats obtained from the stores and supermarkets in matsuyama-city and iyo-city from november, 1987 to october, 1988 were examined and two strains of vero toxin-producing escherichia coli were isolated: one was from beef from australia and the other was from pork from canada. by bead-elisa, it was confirmed that the strain from beef produced vero toxin 1 (vt1) and vero toxin 2 variant (vt2vh) and the strain from pork produced vt2vh. these results s ...19912066599
cloning and sequence analysis of the human liver rhodanese: comparison with the bovine and chicken enzymes.the cdna for the human rhodanese (thiosulfate: cyanide sulfurtransferase, ec, a nuclearly encoded protein of the mitochondrial matrix, was isolated from a human fetal liver cdna library. nucleotide sequence revealed an open reading frame coding for a polypeptide of 295 amino acids, which presented a 57% and 58% identity with the bovine and avian rhodanese, respectively. the analysis of the 5'-ends of the coding region gave no evidence for the presence of a cleavable signal sequence as f ...19911953758
intramammary challenge with escherichia coli following immunization with a curli-producing escherichia coli.holstein and jersey cattle were immunized with a curli-producing strain of escherichia coli (pcrl65/a012) or a noncurli-producing strain (puc18/hb101) to determine differences in resistance to establishment of experimental intramammary infection. cows (n = 6 per group) were immunized at 14 d prior to drying off, 7 d of involution, and at calving with 3 x 10(10) e. coli in freund's incomplete adjuvant. at 30 d of lactation, one mammary quarter of each cow was infused with a wild strain of e. coli ...19912071713
analyzing the substrate specificity of saccharomyces cerevisiae myristoyl-coa:protein n-myristoyltransferase by co-expressing it with mammalian g protein alpha subunits in escherichia coli.a dual plasmid system was used to examine the protein and acyl-coa specificities of saccharomyces cerevisiae myristoyl-coa:protein n-myristoyltransferase (nmt) by co-expressing it in escherichia coli with each of four homologous alpha subunits of the signal-transducing, heterotrimeric g proteins. exogenous [3h]myristate was incorporated into rat gi alpha 1 and rat go alpha but not into bovine gs alpha or human gz alpha. oxygen for methylene group substitutions in myristate result in analogs with ...19911903791
rsr1 and rap1 gtpases are activated by the same gtpase-activating protein and require threonine 65 for their activation.the rsr1 protein of saccharomyces cerevisiae has been shown to be essential for bud site selection (bender, a., and pringle, j. (1989) proc. natl. acad. sci. u.s.a. 86, 9976-9980). this protein of 272 amino acids shares approximately 50% sequence identity with both ras and rap gtpases. however, neither gtp binding nor gtpase activity of the rsr1 protein has been reported. the rsr1 protein shares with human rap1 gtpases the four specific motifs, i.e. gly-12, residues 32-40, ala-59, and residues 6 ...19911910037
expression of tac antigen component of bovine interleukin-2 receptor in different leukocyte populations infected with theileria parva or theileria annulata.the tac antigen component of the bovine interleukin-2 receptor was expressed as a cro-beta-galactosidase fusion protein in escherichia coli and used to raise antibodies in rabbits. these antibodies were used for flow cytofluorimetric analysis to investigate the expression of tac antigen in a variety of theileria parva-infected cell lines and also in three theileria annulata-infected cell lines. cells expressing tac antigen on their surface were found in all t. parva-infected cell lines tested wh ...19901979317
pseudomonas cepacia adherence to respiratory epithelial cells is enhanced by pseudomonas aeruginosa.pseudomonas aeruginosa and pseudomonas cepacia are both opportunistic pathogens of patients with cystic fibrosis. the binding characteristics of these two species were compared to determine if they use similar mechanisms to adhere to respiratory epithelial cells. p. cepacia 249 was shown to be piliated, but there was no detectable homology between p. aeruginosa pilin gene probes and p. cepacia genomic dna. p. cepacia and p. aeruginosa did not appear to compete for epithelial receptors. in the pr ...19901983811
rhizobium meliloti adenylate cyclase is related to eucaryotic adenylate and guanylate cyclases.a gene from rhizobium meliloti coding for an adenylate cyclase was sequenced, and the deduced protein sequence was compared with those of other known adenylate cyclases. no similarity could be detected with the procaryotic counterparts. however, striking similarity was found with the catalytic region of saccharomyces cerevisiae adenylate cyclase, the cytoplasmic domains of bovine adenylate cyclase, and two mammalian guanylate cyclases. the gene was fused to the enteric beta-galactosidase, and th ...19901970565
the effect of interferon-gamma intramammary administration on mammary phagocyte function.the effect of recombinant bovine interferon-gamma on intramammary phagocyte function of mammary gland was studied in 4 holstein cows (study 1) and 7 holstein cows (study 2). recombinant bovine interferon-gamma was intramammarily infused on day 6 of the dry period and phagocytes were collected from lacteal secretions and tested in vitro 24 hours later. results from study 1 indicate that phagocytosis of escherichia coli and staphylococcus aureus was significantly increased after than before interf ...19902111962
interactions of the bovine brain a1-adenosine receptor with recombinant g protein alpha-subunits. selectivity for rgi alpha-3.the ability of the bovine brain a1-adenosine receptor to discriminate between different g protein subtypes was tested using g protein alpha-subunits synthesized in escherichia coli (rg alpha-subunits). when combined with a 3-fold molar excess of beta gamma-subunit purified from bovine brain and used at high concentrations, all three subtypes of rgi alpha (rgi alpha-1, rgi alpha-2, and rgi alpha-3) and rgo alpha were capable of reconstituting guanine nucleotide-sensitive high-affinity binding of ...19911917922
immunoreactive alpha a crystallin in rat non-lenticular tissues detected with a sensitive immunoassay method.for the quantitative analysis of the a subunit of alpha crystallin (alpha a) in the lens and for the survey of possible existence of alpha a in the non-lenticular tissues, we have established a highly sensitive and specific immunoassay method for alpha a. antisera to alpha a were raised in rabbits with alpha a purified from bovine lens, or the c-terminal decapeptide (eekpssapss) of alpha a (alpha apep). the antibodies to alpha a and alpha apep were purified by the use of an alpha a-coupled sepha ...19911932094
controlling acute escherichia coli mastitis during the periparturient period with recombinant bovine interferon gamma.the efficacy of recombinant bovine interferon (rboifn)-gamma against experimentally induced escherichia coli mastitis during the periparturient period was investigated. dairy cows intramammarily treated with rboifn-gamma 24 h before the e. coli challenge had fewer infected quarters, lower clinical scores, and infections of shorter duration when compared to placebo-treated animals. all rboifn-gamma treated cows survived the experimental e. coli challenge. however, placebo treated cows had a 42% m ...19911908159
preliminary characterization of a cloned neutral isoelectric form of the human peptidyl prolyl isomerase cyclophilin.we report the cloning of a neutral isoelectric form of the human peptidyl prolyl isomerase, cyclophilin, its expression in escherichia coli, and its purification and comparison to bovine thymus cyclophilin. the cloned protein exhibited a pi of approximately 7.8 and formed a simple 1:1 complex with cyclosporin a. this cloned form had a pi similar to that observed for the neutral isoform (pi approximately 7.4) of human splenocyte cyclophilin. the bovine thymus proteins exhibited anomalous behavior ...19911989998
[bacterial penetration of bovine dentinal tubules. 1].the penetration by bacteria through dentinal tubules was studied using a device that included portion of bovine anterior teeth. strains of 4 genera, streptococcus mutans, lactobacillus casei, staphylococcus aureus and escherichia coli, were used for the experiment, and the effects of acid etching of dentin on the penetration of bacteria through the dentin was examined. the time required for penetration through dentinal tubules of acid-etched samples was shorter than that of unetched samples. the ...19902134917
molecular characterization of bovine brain p75, a high affinity binding protein for the regulatory subunit of camp-dependent protein kinase ii mammalian brain, physiological signals carried by camp seem to be targeted to intraneuronal sites by the association of camp-dependent protein kinase ii beta with anchoring proteins that bind the regulatory subunit (rii beta) of the enzyme. previously, an rii beta-binding domain was characterized in a large (mr approximately 150,000) candidate anchor protein, rat brain p150 (bregman, d. b., bhattacharyya, n., and rubin, c. s. (1989) j. biol. chem. 264, 4648-4656). rii beta-binding proteins wi ...19912016323
the use of plasmid profiles and nucleic acid probes in epidemiologic investigations of foodborne, diarrheal diseases.the application of nucleic acid analyses to investigations of infectious disease outbreaks has resulted in useful molecular strain markers that distinguish the epidemic clone of a particular pathogen and help identify specific vehicles of infection. we have successfully used plasmid profile analysis, restriction endonuclease digestion of plasmid and whole-cell dnas, and nucleic acid hybridization to investigate recent outbreaks of foodborne diarrheal illness. plasmid analysis has been important ...19912018708
the action of 1-nitroso-8-nitropyrene in escherichia coli: dna adduct formation and mutational consequences in the absence of nucleotide study the mechanisms of mutagenesis by the carcinogen 1,8-dinitropyrene we have determined the dna adducts formed and mutations induced by its partially activated metabolite 1-nitroso-8-nitropyrene (1,8-nonp) in an escherichia coli strain deficient in nucleotide excision-repair. using dna sequence analysis we have characterized a collection of 159 laci- mutations recovered following treatment with 1,8-nonp. the mutational spectrum was dominated by -1 frameshifts (110 events) in runs of contig ...19912029753
the influence of anti-inflammatory therapy on bacterial clearance following intramammary escherichia coli challenge in goats.coliform mastitis in dairy cattle frequently results in systemic disease with occasional deaths in association with endotoxic shock. systemic anti-inflammatory therapy has been used to alter the course of endotoxic shock in severe cases. use of anti-inflammatory therapy has been questioned on the basis that such treatment may compromise immune function and decrease clearance of bacteria from infected mammary glands. the purpose of this investigation was to determine whether anti-inflammatory the ...19912068798
production of bovine insulin-like growth factor 2 (bigf2) in escherichia coli.bovine insulin-like growth factor 2 (bigf2) was produced in inclusion bodies in the cytoplasm of escherichia coli and accumulated at high levels: 20-25% of total coomassie-stained bacterial protein. the level of accumulation of bigf2 was affected by the choice of codons in the 5' end of the coding sequence and by a rpoh mutation in the host cells. purified recombinant bigf2 had the native n terminus and the same mitogenic activity as that of bigf2 purified from bovine serum.19912055493
verotoxic escherichia coli in human disease.verotoxin-producing e. coli (most frequently e. coli o157) have been implicated in the pathogenesis of diarrhea, hemorrhagic colitis, hemolytic uremic syndrome and thrombotic thrombocytopenic purpura. cattle, meat products, and other sources have been found to harbor these organisms. isolation of e. coli o157:h7 on macconkey-sorbitol agar is diagnostic, yet the bacteria are difficult to detect after the first week of infection. enzyme linked immunosorbent assays (elisas) can detect verotoxin in ...19912072218
identification of a groes-like chaperonin in mitochondria that facilitates protein folding.mitochondria contain a polypeptide that is functionally equivalent to escherichia coli chaperonin 10 (cpn10; also known as groes). this mitochondrial cpn10 has been identified in beef and rat liver and is able to replace bacterial cpn10 in the chaperonin-dependent reconstitution of chemically denatured ribulose-1,5-bisphosphate carboxylase. thus, like the bacterial homologue, mitochondrial cpn10 facilitates a k(+)- and mg.atp-dependent discharge of unfolded (or partially folded) ribulose bisphos ...19901977163
synthesis of bovine leukemia virus antigens in escherichia coli.plasmids were constructed by the use of pex vectors that encode and express different parts of the bovine leukemia virus (blv): main core protein p24, nucleic acid-binding protein p12, transmembrane protein gp30, and different segments of envelope protein gp51. expression of fusion proteins with molecular weights higher than 117 kd for all recombinant plasmids was shown in coomassie-blue stained gels and by western blot analysis with rabbit anti-blv sera. coupling of a gp51-encoding with a p24-e ...19901966363
immune complex induced experimental colitis: beneficial effect of sulphasalazine in rabbits.experimental colitis was induced in rabbits by exposing the colon mucosa to 1% formalin followed by i.v. injections of soluble immune complexes made with antigen in excess. the animals were preimmunized with escherichia coli o14:k7:h--inducing antibodies cross-reactive to intestinal epithelium. animals with this colitis were divided in two groups. one group was treated with sulphasalazine and the other was given vehicle only. sulphasalazine was administered daily at 125.5 mumol (50 mg) per kg bo ...19901983323
characterization of a new putative colonization factor (cs17) from a human enterotoxigenic escherichia coli of serotype o114:h21 which produces only heat-labile enterotoxin.enterotoxigenic escherichia coli (etec) of serotype o114:h21, which produced only heat-labile enterotoxin (lt), gave mannose-resistant hemagglutination (mrha) with bovine erythrocytes. one strain, e20738a, was shown to possess fimbriae of approximately 7.5 nm diameter. on sds-page two possible fimbrial polypeptides of molecular masses 17.5 and 15.5 kda were seen; the 17.5-kda band was the most prominent. loss of lt and mrha together from strain e20738a was associated with loss of a 100-mda plasm ...19901967623
temporal changes in metabolites of prostanoids in milk of heifers after intramammary infusion of escherichia coli organisms.a study was conducted to characterize the changes in the concentrations of three metabolites of prostanoids in the milk of a) heifers (n = 14; control) inoculated with escherichia coli (e. coli) organisms into the udder and b) in heifers (n = 10; treatment) vaccinated with e. coli bacterin and treated similar to control heifers. milk samples were obtained from the challenged quarter and analyzed for the concentrations of stable metabolites of thromboxane a2 (txb2), prostacyclin (pcm) and prostag ...19902111572
cloning and nucleotide sequence of cdna for ki antigen, a highly conserved nuclear protein detected with sera from patients with systemic lupus erythematosus.patients with systemic lupus erythematosus (sle) produce autoantibodies against a variety of nuclear antigens including ki antigen. although anti-ki autoantibodies were found in a significant number of sle patients, the nature of ki antigen is poorly characterized. by using anti-ki serum as a probe we have cloned a bovine cdna directing the synthesis in escherichia coli of a polypeptide immunologically indistinguishable from the authentic ki antigen. a homologous human cdna was also cloned and i ...19901968796
16s ribosomal dna amplification for phylogenetic study.a set of oligonucleotide primers capable of initiating enzymatic amplification (polymerase chain reaction) on a phylogenetically and taxonomically wide range of bacteria is described along with methods for their use and examples. one pair of primers is capable of amplifying nearly full-length 16s ribosomal dna (rdna) from many bacterial genera; the additional primers are useful for various exceptional sequences. methods for purification of amplified material, direct sequencing, cloning, sequenci ...19911987160
bacteriologic and pathologic studies of hepatic lesions in an abattoir, lesion specimens from 140 condemned sheep livers were collected for bacteriologic culture and for pathologic examination. grossly, 23 lesions were abscesses; from 9 of which, fusobacterium necrophorum biovar a (3 in pure culture and 6 in mixed culture) was isolated and from 14 of which, biovar b (6 in pure culture and 8 in mixed culture) was isolated. escherichia coli was the predominant facultative anaerobic bacterium and clostridium perfringens was the predominant obligate anae ...19902180351
factors influencing the adherence of strains of streptococcus bovis and escherichia coli isolated from ruminal epithelium.two strains of streptococcus bovis (a1 and a5) and one strain of escherichia coli (0141:h28) isolated from the surface of bovine ruminal mucous epithelium were examined for adherence to isolated and cultured ruminal epithelial cells. the e. coli adhered to the target cell by means of fimbriae, which had several common properties with type 1 common fimbriae and caused mannose-sensitive haemagglutination. the a1 strain of s. bovis was devoid of fimbriae and its adherence to the epithelial surface ...19901974372
[experimental udder infection with escherichia coli. 2. morphological changes of the epithelium in the area of the glands of the milk cistern and the large milk ducts].optical light, transmission, and scanning electron microscopy were used in investigations of epithelia in the glandular region of the milk cistern and greater lactiferous ducts and yielded the following findings, four and six hours from infection: degeneration and necrosis of epithelial cells, intraepithelial foreign cell infiltration (neutrophilic granulocytes, lymphocytes, macrophages), intra-epithelial oedema and locally delimited epithelial loss. the lesions differed by intensity in various ...19902096792
identification of enteropathogenic escherichia coli isolated in britain as enteroaggregative or as members of a subclass of attaching-and-effacing e. coli not hybridising with the epec adherence-factor probe.strains of escherichia coli from sporadic cases of diarrhoea and belonging to serotypes o44:h18, o55:h7, o111ab:h21, o111ab:h25 or o126:h27 were examined for virulence properties. with the exception of o111ab:h25 these are considered to be classical enteropathogenic e. coli (epec) serotypes. the strains had been isolated in britain from the faeces of children less than 3 years old. of the serotypes examined, 7 of 13 o44:h18 strains, all of 10 o111ab:h21 strains and 13 of 21 o126:h27 strains belo ...19911941998
mutations in the heparin-binding domains of human basic fibroblast growth factor alter its biological activity.eleven structural analogues of human basic fibroblast growth factor (bfgf) have been prepared by site-directed mutagenesis of a synthetic bfgf gene to examine the effect of amino acid substitutions in the three putative heparin-binding domains on fgf's biological activity. after expression in escherichia coli, the mutant proteins were purified to homogeneity by use of heparin-sepharose chromatography and analyzed for their ability to stimulate dna synthesis in human foreskin fibroblasts. recombi ...19912036431
properties of purine nucleoside phosphorylase (pnp) of mammalian and bacterial origin.purine nucleoside phosphorylase (pnp), from calf spleen, human erythrocytes and e. coli have been examined with regard to structural requirements of substrates and inhibitors. kinetic parameters (km, vmax/km) for a variety of n(1) and/or n(7)-methylated analogues of guanosine, inosine and adenosine have been evaluated for all three enzymes. the substrate and/or inhibitor properties of purine riboside, 1,6-dihydropurine riboside, some deazapurine nucleosides: 3-deaza- and 7-deazainosine, 1,3-dide ...19902109978
administration of bacterial lipopolysaccharide elicits circulating tumor necrosis factor-alpha in neonatal calves.the presence of tumor necrosis factor-alpha (tnf-alpha) during endotoxemia in ruminants has not been reported previously. in this study, we detected the in vivo release of bovine tnf-alpha by using wehi-164 murine fibrosarcoma cells as targets in an 18-h cytotoxicity assay. treatment of the wehi-164 cells with 1 microgram of actinomycin d (dactinomycin) enhanced approximately twofold the susceptibility of the cells to tnf-alpha activity. tnf-alpha activity in sera from neonatal calves injected i ...19902112564
selective carboxyl methylation of structurally altered calmodulins in xenopus oocytes.the eucaryotic protein carboxyl methyltransferase specifically modifies atypical d-aspartyl and l-isoaspartyl residues which are generated spontaneously as proteins age. the selectivity of the enzyme for altered proteins in intact cells was explored by co-injecting xenopus laevis oocytes with s-adenosyl-l-[methyl-3h]methionine and structurally altered calmodulins generated during a 14-day preincubation in vitro. control experiments indicated that the oocyte protein carboxyl methyltransferase was ...19902123492
mitochondrial atp synthase. cdna cloning, amino acid sequence, overexpression, and properties of the rat liver alpha subunit.the predicted amino acid sequence of the alpha subunit of the rat liver mitochondrial atp synthase has been obtained by sequencing a cdna for the alpha subunit. analysis of the sequence shows that it contains the a and b consensus sequences found in many nucleotide-binding proteins. twelve amino acids of the rat liver alpha subunit differ from the sequence of the bovine heart alpha subunit; four of these involve differences in charge. the rat liver alpha subunit, from arginine 15 to the c-termin ...19902137825
a synthetic 13-residue peptide corresponding to the hydrophobic region of bovine seminalplasmin has antibacterial activity and also causes lysis of red blood cells.seminalplasmin (spln), a 47-residue peptide present in bovine seminal plasma, is one of the few proteins isolated from mammalian sources having potent antibacterial activity. spln also interacts with sperm acrosomal and plasma membranes. on the basis of analysis of the primary structure of spln with respect to its relative hydrophobicity and hydrophilicity, a region comprising of 13-amino acids, pro-lys-leu-leu-glu-thr-phe-leu-ser-lys-trp-ile-gly, has been delineated. it is demonstrated that a s ...19902113055
characterization of a thermostable bacillus stearothermophilus alpha-amylase.liquefying-type bacillus stearothermophilus alpha-amylase was characterized. the coding gene was cloned in bacillus subtilis and the enzyme was produced in three different host organisms: b. stearothermophilus, b. subtilis, and escherichia coli. properties of the purified enzyme were similar irrespective of the host. temperature optimum was at 70-80 degrees c and ph optimum at 5.0-6.0. the enzyme was stable for 1 h in the ph range 6.0-7.5 at 80 degrees c. the enzyme was stabilized by ca2+, na+, ...19902119192
protection of cattle and swine against foot-and-mouth disease, using biosynthetic peptide vaccines.a single dose of foot-and-mouth disease (fmd) virus protein 1 (vp1) peptide, expressed in escherichia coli as a fusion protein with 190 amino acids (aa) of the le' protein of the tryptophan operon of e coli, elicited an immune response in steers sufficient to withstand the challenge of exposure to animals with acute fmd. the 58-micrograms dose of viral peptide, composed of a segment of the vp1 from the a12 strain (a12) of fmd virus (fmdv; a12-32dimer) in a tandem repeat configuration of aa137 th ...19902154148
isolation of escherichia coli serotype o157:h7 and other shiga-like-toxin-producing e. coli from dairy cattle.we examined 1,266 fecal specimens from healthy cattle during the investigations of two sporadic cases of hemolytic uremic syndrome associated with raw milk consumption and an outbreak of gastroenteritis and hemolytic uremic syndrome caused by escherichia coli serotype o157:h7. we collected specimens from heifers, calves, and adult cows on 22 farms, in a stockyard, and in a packing house. we also collected 3 raw hamburger specimens from a restaurant and 23 raw milk samples from two farms. all spe ...19912056066
[expression in escherichia coli of hybrid genes containing sequences coding the bovine adrenocorticotropic hormone].e. coli strains producing a hybrid protein, containing adrenocorticotropic hormone (acth) and protein a of s. aureus was obtained. the sequence coding for acth was obtained from the bovine proopiomelanocortin cdna and, after the modification of the 5'- and 3'-terminal parts, was linked with the protein a gene and its derivatives due to synthetic adaptors. three forms of acth gene, coding this hormone with differing n-terminal amino acid were used to construct the fusion gene. the hybrid proteins ...19902161493
homologous recombination in a mammalian plasmid.bovine papillomavirus (bpv) shuttle vectors replicate as a circular plasmid in mouse cell nuclei without impairing host cell viability. we used these vectors to analyze homologous recombination in mammalian cells. when several bpv-based plasmids carrying direct repeats were introduced into c127 cells, we detected many recombinant plasmid molecules that have lost the sequence between the repeats. many recombinant type molecules as well as parental type molecules were detected in all the cell clon ...19902177135
[hemolytic-uremic syndrome: association with vero cytotoxin-producing escherichia coli. an epidemiological and microbiological study on possible animal reservoirs].vero cytotoxin-producing strains of escherichia coli (vtec) appear to be in man associated with a range of clinical symptoms from mild non bloody diarrhoea to haemorrhagic colitis and severe haemolytic uraemic syndrome (hus). we present two patients affected by hus who were investigated to determine evidence of infection by vtec. in one of the patient free fecal cytotoxin active on vero cells was detected as well as seroconversion of vt-neutralizing antibody titre. both children were living in t ...19902093884
cross-reactive affinity purification of immunoglobulin recognizing common gram-negative bacterial core antigens.a procedure isolating immunoglobulins specific for common gram-negative bacterial core antigens is described. a polyclonal reagent was purified by ammonium sulfate precipitation, dialysis, and column affinity chromatography. the initial vaccinal antigen was an ra mutant escherichia coli o111:b4 (strain j5). the capture antigen was lipopolysaccharide derived from an ra mutant, salmonella typhimurium tv119 covalently-linked to an agarose matrix. column eluants were characterized in terms of total ...19902191044
an intrinsic tonoplast protein of protein storage vacuoles in seeds is structurally related to a bacterial solute transporter (gipf).the tonoplast mediates the transport of various ions and metabolites between the vacuole and cytosol by mechanisms that remain to be elucidated at the molecular level. the primary structure of only one tonoplast protein, the h(+)-atpase, has been reported to date. here we report the primary structure of tonoplast intrinsic protein (tip), a 27-kilodalton intrinsic membrane protein that occurs widely in the tonoplasts of the protein storage vacuoles (protein bodies) of seeds [johnson, k.d., et al. ...19902152174
genetic reconstruction and characterization of the recombinant transacylase (e2b) component of bovine branched-chain alpha-keto acid dehydrogenase complex. implication of histidine 391 as an active site residue.genetically altered transacylase (e2b) proteins of the bovine branched-chain alpha-keto acid dehydrogenase complex were overexpressed in escherichia coli and characterized. deletion by psti or bal31 digestion of the amino-terminal region of the inner-core domain (residues 175-421) beyond residue 209 resulted in a complete loss of transacylase activity. the enzyme assay was carried out using [1-14c]isovaleryl-coa and exogenous dihydrolipoamide as substrates. the removal of 4 residues (thr-ile-pro ...19902198287
differences in susceptibility of inbred and outbred infant mice to enterotoxigenic escherichia coli of bovine, porcine and human origin.infant mice from outbred swiss of1 and from inbred dba/2, c57bl/6, balb/cby and cba strains were screened for usefulness in the diarrhoea model with enterotoxigenic escherichia coli (etec) strains of bovine, porcine and human origin. mouse strains were either weakly susceptible or not susceptible to etec strains of porcine or human origin bearing antigen k88, 987p, cfa/i or cfa/ii. in contrast, some mouse strains were highly susceptible to bovine and porcine etec strains bearing k99 or f41 or bo ...19902179554
effects of allopurinol on endotoxin-induced increase in serum xanthine oxidase in the horse.using a modified bovine milk enzyme kinetic assay, xanthine oxidase activity of serum collected from 34 adult, healthy horses of both sexes was determined. enzyme activity varied from 0 to 126 mu litre-1 with a mean of 44.95 +/- 21.05 mu litre-1. the optimal ph and temperature for maximal activity were 7.8 and 28 degrees c, respectively. freezing the serum for four days at -70 degrees c did not destroy the enzyme activity. various doses (25, 50 and 75 micrograms kg-1, intraperitoneally) of endot ...19902200092
persistent excretion of rotavirus by pregnant a study of the epizootiology and prevalence of enteropathogens which may be involved in neonatal calf diarrhoea, 10 in-calf cows from a herd with a history of rotavirus-induced calf diarrhoea were monitored over a period of six to seven months. all the cows excreted rotavirus intermittently without showing any clinical signs, and 21.8 per cent of faecal samples contained rotavirus. reoviruses were isolated from 87 per cent of the samples from the cows, and from all the 10 calves born to them. ...19902164274
sequential initiation of lagging and leading strand synthesis by two different polymerase complexes at the sv40 dna replication origin.enzymatic synthesis of dna from the simian virus 40 origin of dna replication has been reconstituted in vitro with eight purified components. dna polymerase alpha-primase complex first initiates dna synthesis at the replication origin and continues as the lagging strand polymerase. subsequently, the dna polymerase delta complex initiates replication on the leading strand template. some prokaryotic dna polymerase complexes can replace the eukaryotic polymerase delta complex. a model for polymeras ...19902165567
evidence for nonintercalative complexes formed from the reversible binding of benzo[a]pyrene metabolites to closed-circular, single-stranded m13mp19 dna.the fluorescence excitation spectrum of complexes formed from the reversible binding of the proximate carcinogen, trans-7,8-dihydroxy-7,8-dihydro-benzo[a]pyrene (bp78d) to closed-circular, single-stranded, viral m13mp19 dna (ss m13 dna) exhibits a red-shift of 5 nm compared to the spectrum of bp78d measured without dna or with native, calf thymus dna. in ss m13 dna which is 0.10 mm in po4-, the fluorescence intensity of bp78d is 2.3 times smaller than the intensity measured without dna; however, ...19902189401
1h nmr resonance assignments, secondary structure, and global fold of apo bovine calbindin d9k.the solution structure and dynamics of apo bovine calbindin d9k have been studied by a wide range of two-dimensional 1h nuclear magnetic resonance experiments. due to the presence of conformational heterogeneity in the wild-type protein, the sequential resonance assignment was carried out on a pro43----gly mutant. by use of a combination of scalar correlation experiments acquired from h2o solution, 61 of the 76 1h spin systems could be assigned to particular amino acid types. the remaining reson ...19902200514
the f1 atp synthetase beta-subunit: a major yeast novobiocin binding protein.novobiocin affects dna metabolism in both prokaryotes and eukaryotes, resulting in cell death. in prokaryotes, the drug is a specific inhibitor of dna gyrase, a type ii topoisomerase that can be purified on a novobiocin-sepharose column. the yeast type ii topoisomerase is neither the biochemical, nor the genetic target of the antibiotic. we have purified the major yeast novobiocin binding proteins and identified one of them as the beta-subunit of the yeast mitochondrial f1 atp synthetase, a prot ...19902178164
the production, purification, and bioactivity of recombinant bovine trophoblast protein-1 (bovine trophoblast interferon).bovine trophoblast protein-1 (btp-1) is a 172-amino acid interferon- alpha that has a role in maternal recognition of pregnancy in cattle. here we describe production of btp-1 by recombinant procedures in escherichia coli. a btp-1 gene was constructed which lacked the codons representing the signal sequence and provided a met initiation codon ahead of the tgt codon encoding cys1 of the mature protein. this construct was placed under the control of the trp promoter within the expression vector pt ...19902178217
site-directed mutations of human growth hormone that selectively modify its lactogenic activity and binding properties.two novel analogs of human (h) gh, 1) des-7-hgh (arg8met, asp11ala) in which the arg8 was substituted by met and asp11 by ala, and 2) bovine (b) gh/hgh hybrid ii (metala 1-13/14-191, ala11asp) composed of 13 n-terminal amino acid of bgh and elongated by two amino acids (met-ala-1-13) and 14-191 amino acids of hgh, were constructed and expressed in escherichia coli. cd spectra indicated that the alpha-helix content of the purified proteins was similar to that of the native hormone. both analogs r ...19902178223
modulation of resistance to mastitis pathogens by pretreatment of mice with t-2 toxin.t-2 toxin, a secondary metabolite of fusarium species, is a mycotoxin with immunomodulatory activity. in the present investigation the effects of t-2 toxin on host resistance was studied. the virulence of escherichia coli and staphylococcus aureus in the mammary glands of mice treated with t-2 toxin was compared with their virulence in control mice. virulence was estimated from the ability to induce various types of lesions and bacterial growth in the mammary gland. pretreatment of mice with a s ...19902276697
separation of sublethal and lethal effects of the bactericidal/permeability increasing protein on escherichia coli.binding of the bactericidal/permeability increasing protein (bpi) of granulocytes to escherichia coli promptly produces several discrete outer envelope alterations and growth arrest without major impairment of bacterial structure or biosynthetic capabilities, raising the question whether these early effects of bpi are sufficient to cause bacterial death. in this study, the bactericidal action of bpi was examined more closely. we have found that bovine or human serum albumin blocks bacterial kill ...19902179269
the three-dimensional structure of recombinant bovine chymosin at 2.3 a resolution.the crystal structure of recombinant bovine chymosin (ec; renin), which was cloned and expressed in escherichia coli, has been determined using x-ray data extending to 2.3 a resolution. the crystals of the enzyme used in this study belong to the space group i222 with unit cell dimensions alpha = 72.7 a, b = 80.3 a, and c = 114.8 a. the structure was solved by the molecular replacement method and was refined by a restrained least-squares procedure. the crystallographic r factor is 0.165 ...19902217166
specific interaction of the murine transcription termination factor ttf i with class-i rna polymerases.the 18-base-pair sequence element aggtcgaccagtactccg (the sal box) signals termination of mouse ribosomal gene transcription. this sequence is recognized by a sequence-specific dna-binding protein, ttf i, which mediates the termination of transcription by rna polymerase i (pol i). subsequently, the ends of the primary transcripts are trimmed by 10 nucleotides in a sequence-dependent 3'-terminal processing reaction. we have now investigated whether ttf i bound to its target sequence will block el ...19902181320
expression of antigens from chromosomal and linear plasmid dna of borrelia coriaceae.three recombinant plasmids containing dna from borrelia coriaceae, the putative agent of epizootic bovine abortion, expressed antigens in escherichia coli that reacted with antibodies specific for b. coriaceae. two of the recombinants each expressed a single high-molecular-weight antigen. the third recombinant expressed three smaller antigens. the dna inserts were sized and mapped. hybridization of the cloned inserts to pulsed-field electrophoresis samples of b. coriaceae whole-cell dna revealed ...19902341175
polyisoprenylation of ras in vitro by a farnesyl-protein transferase.farnesylation of ras occurs in vivo on a cys residue in the c-terminal sequence -cys-val-leu-ser (termed a caax box). this modification is required for ras membrane localization and cell transforming activity. using [3h]farnesyl-ppi as precursor and escherichia coli-expressed ras, forms of ras having the caax sequence were radiolabeled upon incubation with the cytosolic fraction of bovine brain. forms of ras having a deletion of the caax sequence or a cys to ser substitution in this sequence wer ...19902203759
sympathico-adrenal effects of endotoxaemia in cattle.intradermal injection of 46 micrograms e coli endotoxin had no effect on the plasma cortisol and noradrenaline concentrations of four dairy cows. mean values were similar to normal values reported in the literature. intravenous injection of 75 micrograms of endotoxin on the following day caused a massive increase in plasma cortisol concentrations which lasted for seven hours. plasma noradrenaline concentrations increased rapidly after the intravenous administration of endotoxin and remained high ...19902201125
production of recombinant human tropoelastin: characterization and demonstration of immunologic and chemotactic activity.tropoelastin cannot readily be prepared in quantity from natural sources and this has limited research in several important areas including structure/function relationships and fiber assembly. in order to eliminate this limitation, human tropoelastin has been expressed in a recombinant bacterial system and the protein has been highly purified. the size, amino acid composition, and sequence of the amino terminus of the recombinant tropoelastin (rte) all agree with values predicted by the nucleoti ...19902191629
phagocytosis, bactericidal activity, and oxidative metabolism of milk neutrophils from dairy cows fed selenium-supplemented and selenium-deficient diets.six primiparous holstein cows were fed a se-deficient diet, beginning at least 90 days before their first calving, and 6 other primiparous cows were given the same diet plus a supplement of 2 mg of se/cow/d as sodium selenite. all cows were fed their diets for the duration of the experimental period. one uninfected quarter of each cow was injected with 25 micrograms of escherichia coli endotoxin at postpartum week 5. leukocytes were isolated by centrifugation from milk collected at postinjection ...19902405755
point mutations in a pbr322-based expression plasmid resulting in increased synthesis of bovine growth hormone in escherichia coli.the bgh cdna coding for bovine growth hormone (bgh) is expressed poorly in escherichia coli using a pbr322-based expression plasmid. random mutagenesis of the plasmid gave rise to two types of plasmid mutants which increased the expression of bgh. one class had single base changes in the first four codons of the bgh sequence. the second class had single base changes in regions of the plasmid involved in controlling plasmid replication but had little effect on plasmid copy number.19902182388
preinfection functions of blood polymorphonuclear leukocytes and the outcome of experimental escherichia coli mastitis in the cow.the relationship between preinfection functions of blood neutrophils and outcome of experimental escherichia coli mastitis was studied in 11 cows. random migration, chemotaxis, phagocytosis, and chemiluminescence by neutrophils were determined in white blood cell suspensions, and in purified neutrophil suspensions. the course of e. coli mastitis (10(4) e. coli 0:157 in rear quarters) was monitored using clinical parameters, counts of e. coli in mastitic secretion, and milk production. regression ...19902184174
expression and assembly of mature apotransacylase (e2b) of bovine branched-chain alpha-keto acid dehydrogenase complex in escherichia coli. demonstration of transacylase activity and modification by lipoylation.a cdna clone encoding the entire transacylase (e2b) precursor of the bovine branched-chain alpha-keto acid dehydrogenase complex (griffin, t. a., lau, k. s., and chuang, d. t. (1988) j. biol. chem. 263, 14008-14014) was used to construct a prokaryotic expression vector for recombinant mature e2b. the overexpression in escherichia coli correlates with the presence near the 5'-terminus of the mature e2b coding region (nucleotides 20 to 28) of the sequence 5'-tcaaact-ct-3'. it has been proposed tha ...19902195031
virulent escherichia coli strains for chicks bind fibronectin and type ii collagen.125i-fibronectin and 125i-collagen (type ii) binding was detected in escherichia coli strains isolated from chickens and poults. high fibronectin binding-strains also bind the 29 kd aminoterminal fragment of fibronectin. binding properties in strain ck28 were partially characterized. the highest binding of 125i-fibronectin and 125i-collagen for strain ck28 was obtained with bacteria grown at 33 degrees c. binding of 125i-fibronectin, its 125i-29 kd fragment, and 125i-collagen, was very rapid, re ...19902196415
cellular requirements for anti-dna production induced in mice by immunization with bacterial further define dna immunization as a model for anti-dna production, we investigated the cellular requirements for this response in mice immunized with single-stranded dna from e. coli. the anti-dna responses of genetically immune-deficient mice and congenic controls were measured by elisa after immunization with e. coli dna as complexes with methylated bovine serum albumin in complete freund's adjuvant. t cell-deficient balb/c-nu/nu mice failed to produce igg anti-dna by this protocol despite ...19902209690
a statewide outbreak of escherichia coli o157:h7 infections in washington november 1986, a statewide outbreak of escherichia coli o157:h7 infections in washington state was identified after a physician in an eastern washington community hospitalized three patients with hemorrhagic colitis which progressed to thrombotic thrombocytopenic purpura. epidemiologic investigation identified 37 cases in this community and linked the illnesses to a local restaurant which had served ground beef that was the suspected initial vehicle of transmission. the plasmid profile and to ...19902196790
protein stability and electrostatic interactions between solvent exposed charged side investigate the contribution to protein stability of electrostatic interactions between charged surface residues, we have studied the effect of substituting three negatively charged solvent exposed residues with their side-chain amide analogs in bovine calbindin d9k--a small (mr 8,500) globular protein of the calmodulin superfamily. the free energy of urea-induced unfolding for the wild-type and seven mutant proteins has been measured. the mutant proteins have increased stability towards unfo ...19902217161
growth of gram-negative bacteria in dry cow secretion.gram-negative bacteria (n = 192) isolated from infected bovine mammary glands were tested for growth in a pooled source of dry cow secretion. growth of klebsiella pneumoniae in dry cow secretion was greater than growth of escherichia coli and klebsiella oxytoca. escherichia coli originating during the early dry period exhibited greater growth in dry cow secretion than those originating around calving or during lactation. klebsiella pneumoniae growth did not differ with time of origin of intramam ...19902184175
melibiose permease and alpha-galactosidase of escherichia coli: identification by selective labeling using a t7 rna polymerase/promoter expression system.identification and selective labeling of the melibiose permease and alpha-galactosidase in escherichia coli, which are encoded by the melb and mela genes, respectively, have been accomplished by selectively labeling the two gene products with a t7 rna polymerase expression system [tabor, s., & richardson, c. c. (1985) proc. natl. acad. sci. u.s.a. 82, 1074]. following generation of a novel ecori restriction site in the intergenic sequence between the two genes of the mel operon by oligonucleotid ...19902159786
cdna cloning and chromosomal assignment of the human o6-methylguanine-dna methyltransferase. cdna expression in escherichia coli and gene expression in human cells.the o6-methylguanine-dna methyltransferases are the most common form of cellular defense against the biological effects of o6-methylguanine in dna. by screening a cdna library with oligonucleotide probes derived from the active site amino acid sequence of the bovine methyltransferase, we have isolated a cdna clone for the human enzyme. the cdna contains a single open reading frame encoding a protein of mr 21,700 which exhibits considerable homology to three bacterial methyltransferases. when pro ...19902188979
intramammary challenge of the bovine mammary gland with coliform bacteria during early involution.isolates of escherichia coli (n = 12), klebsiella pneumoniae (n = 20), and klebsiella oxytoca (n = 10) were used to challenge involuting mammary glands at 7 d of the dry period. bacteria were selected for challenge on the basis of their ability to grow in a pooled source of dry cow secretion obtained at 21 d of involution. challenge bacteria were classified as highly adapted (in vitro growth greater than 7 cfu log10/ml) or poorly adapted (growth less than 2 cfu log10/ml) for growth in dry cow se ...19902195077
prevalence of mastitis in imported friesian cows in sudan.three hundred twenty-two lactating friesian cows were examined for mastitis by different diagnostic techniques. the predominant pathogens encountered were staphylococci, streptococci, corynebacterium and escherichia coli spp.19902218036
characterization of an immunoprotective protein complex of anaplasma marginale by cloning and expression of the gene coding for polypeptide am105l.immunization with an anaplasma marginale surface protein complex containing two polypeptides (am105u and am105l), each having a molecular weight of 105,000, protected cattle against challenge with virulent organisms. these polypeptides were immunoprecipitated together from detergent extracts of a. marginale by a neutralizing monoclonal antibody. after surface radioiodination of intact parasites, both am105u and am105l contained the radiolabel. to define the structural and antigenic relationships ...19872443451
identification of the map2- and p75-binding domain in the regulatory subunit (rii beta) of type ii camp-dependent protein kinase. cloning and expression of the cdna for bovine brain rii beta.cdna clones coding for the regulatory subunit (rii beta) of type ii camp-dependent protein kinase were isolated from a bovine brain cdna expression library in lambda gt11. the cdna codes for a protein of 418 amino acids which is 98% homologous to the rat and human rii beta proteins. a series of expression vectors coding for truncated rii beta proteins were constructed in path plasmids and fusion proteins were expressed in escherichia coli. polyclonal and monoclonal antibodies made against purifi ...19902254332
a bifunctional fusion protein containing fc-binding fragment b of staphylococcal protein a amino terminal to antidigoxin single-chain fv.a bifunctional molecule was genetically engineered which contained an amino-terminal effector domain that bound immunoglobulin fc (fragment b of staphylococcal protein a) and a carboxyl-terminal domain that bound digoxin [a single-chain fv (sfv)]. effector and sfv binding properties were virtually identical with those of the parent molecules, despite the proximity of the fb to the sfv combining site. this finding is unprecedented since in all molecules of the natural immunoglobulin superfamily, ...19902261460
expression of fatty acid-binding protein from bovine heart in escherichia coli.the coding part of the cdna of cardiac fatty acid-binding protein (cfabp) from bovine heart was cloned into the vector pkk233-2. after induction with isopropyl-beta-d-thiogalactopyranoside cfabp was found in a soluble form in the cytosol of plasmid transformed e. coli amounting up to 5.7% of the soluble protein. cfabp was detected after sds-polyacrylamide gelelectrophoresis and/or isoelectric focusing and western blot by immuno-staining and was determined quantitatively by a solid phase enzyme-l ...19902266972
increased sensitivity of the rapid hydrophobic grid membrane filter enzyme-labeled antibody procedure for escherichia coli o157 detection in foods and bovine feces.several strains of escherichia coli o157:h7 artificially inoculated into vegetables and dairy products were recovered on hydrophobic grid membrane filters and enumerated by an enzyme-labeled antibody assay. the mean of the recoveries from 12 fresh vegetables was 108.8%, whereas that from 10 dairy products was 93.2%. modified tryptic soy broth at 43 degrees c with shaking at 100 rpm provided optimum recovery of the organism from meat, with a sensitivity of less than or equal to 1 cfu/g, which is ...19902268161
translation of preprochymosin in vitro. evidence for folding of prochymosin to the native conformation.1. the cdna coding for preprochymosin has been sub-cloned into the transcription/translation vector pgem-3z, the t7 promoter used to transcribe the gene and the product expressed in an 'in vitro' cell-free system comprising rabbit reticulocyte lysate and dog pancreatic microsomes. 2. translations in various conditions, and analyses of the translation product in reducing and non-reducing conditions, indicate that oxidizing translation conditions and the cleavage of the n-terminal 'pre-' sequence ...19902268293
hemagglutination and hemolysis by escherichia coli isolated from bovine intramammary infections.seventy-six escherichia coli isolated from bovine intramammary infections were tested for hemagglutination and hemolysis of erythrocytes. fifty-seven percent of isolates were hemagglutination-positive for bovine erythrocytes compared with 46% that agglutinated guinea pig erythrocytes. twenty-eight percent of isolates were hemagglutination-positive for erythrocytes from both species. only 14.5 and 2.6% of isolates were mannose-resistant, hemagglutination-positive for bovine and guinea pig erythro ...19902273142
human complex ii (succinate-ubiquinone oxidoreductase): cdna cloning of iron sulfur (ip) subunit of liver mitochondria.complex ii (succinate-ubiquinone oxidoreductase) is an important enzyme complex of both the tricarboxylic acid cycle and of the aerobic respiratory chains of mitochondria in eukaryotic cell and prokaryotic organisms. in this study, the amino acid sequence of iron sulfur-subunit in human liver mitochondria was deduced from cdna which was isolated by immunoscreening a human liver lambda gtll cdna library. an isolated clone contains an open reading frame of 786 nucleotides and encodes a mature prot ...19902302193
experimental observations on the pathogenesis of necrobacillosis.earlier studies showed that the minimum infective dose (greater than 10(6) organisms) of a virulent strain of fusobacterium necrophorum could be greatly reduced by suspending the fusobacteria in sub-lethal doses of cultures of other bacteria such as escherichia coli before inoculating mice subcutaneously. in the present study the infective dose of the same strain of f. necrophorum was reduced by a factor of greater than 10(3) by suspending the fusobacteria in sub-lethal doses of 5% homogenate of ...19902307186
the gene sequence and some properties of protein h. a novel igg-binding protein.the gene for protein h, a novel bacterial cell wall protein with specific affinity for human igg fc, was cloned from a group a streptococcus and expressed in escherichia coli. recombinant e. coli cells produced two forms of a human igg fc-binding protein, one with an apparent mr of 42 kda in a periplasmic fraction and the other with an apparent mr of 45 kda in a mixed fraction of cytoplasms and membranes. both 42-kda and 45-kda protein preparations similarly bound to human igg1 to igg4, human ig ...19902332638
physiological responses to intramammary or intravenous treatment with endotoxin in lactating dairy cows.twenty-one, middle to late lactation holstein cows were assigned to one of three treatments in a completely randomized design to examine physiological changes associated with intramammary or intravenous administration of escherichia coli endotoxin. treatments were 1) hank's balanced salt solution infusion in two contralateral quarters (control), 2) e. coli endotoxin infusion in two contralateral quarters, and 3) intravenous infusion of e. coli endotoxin. blood was sampled and rectal temperature ...19902341638
glycoprotein glycans that inhibit adhesion of escherichia coli mediated by k99 fimbriae: treatment of experimental colibacillosis.calf diarrhea due to infection by enterotoxigenic escherichia coli was treated by administration of glycoprotein glycans derived from bovine plasma. the glycan moieties of the nonimmunoglobulin fraction of plasma mimicked the oligosaccharide moiety of intestinal receptors recognized by k99 pili. these glycoprotein glycans inhibited adhesion of e. coli k99+ st+ to erythrocyte glycoconjugates in vitro, and they protected colostrum-deprived newborn calves against lethal doses of enterotoxigenic e. ...19902403535
superoxide dismutases enhance the rate of autoxidation of 3-hydroxyanthranilic acid.the autoxidation of 3-hydroxyanthranilate to cinnabarinate at 37 degrees c and at ph 7.4 is hastened by superoxide dismutase (sod). the cu,zn-containing enzyme from bovine erythrocytes and the mn-containing enzyme from escherichia coli were equally effective in this regard; whereas the h2o2-inactivated cu,zn enzyme was ineffective. catalase appears to augment the effect of superoxide dismutase, because it prevents the bleaching of cinnabarinate by h2o2. it follows that o2-, which is a product of ...19902404453
analysis of clathrin light chain-heavy chain interactions using truncated mutants of rat liver light chain lcb3.clathrin light chains are extended molecules located along the proximal segment of each of the three heavy chain legs of a clathrin trimer. all mammalian light chains share a central segment with 10 repeated heptad motifs believed to mediate the interaction with clathrin heavy chains. in order to test this model in more detail, we have expressed intact rat liver clathrin light chain lcb3 in escherichia coli and find that it binds tightly to calf clathrin heavy chains. using a set of expressed tr ...19902406259
are many z-dna binding proteins actually phospholipid-binding proteins?we used a z-dna affinity column to isolate a collection of z-dna binding proteins from a high salt extract of escherichia coli. we identified one of the major z-dna binding proteins of this fraction, not as a protein involved in gene regulation or genetic recombination, but rather as an outer membrane porin protein. we then showed that several other known phospholipid-binding proteins (bovine lung annexins and human serum lipoproteins) also bind much more tightly to z-dna than to b-dna. in all c ...19902406717
high level, regulated expression of the chimeric p-enolpyruvate carboxykinase (gtp)-bacterial o6-alkylguanine-dna alkyltransferase (ada) gene in transgenic mice.transgenic animals expressing genes capable of repairing dna may be a valuable tool to study the effect of dna-damaging agents on tissue-specific carcinogenesis. for this reason, we constructed a chimeric gene consisting of the promoter-regulatory region of the phosphoenolpyruvate carboxykinase (gtp) (ec (pepck) gene linked to the escherichia coli ada gene coding for o6-alkylguanine-dna alkyltransferase and the polyadenylate region from the bovine growth hormone gene. the pepck promote ...19902407342
serological comparison of the escherichia coli prototype strains for the f(y) and att 25 adhesions implicated in neonatal diarrhoea in calves.slide agglutination tests using single absorbed and double absorbed antisera indicated that the att 25 prototype escherichia coli strain 25 kh9 produces the f(y) adhesion; that this e coli also produces at least one other surface antigen not found on the f(y) prototype e coli strain 11a; and that f(y)+ e coli strain 28a produces at least one other surface antigen not produced by the prototype strains for the f(y) and att 25 antigens. these antigens were found on e coli isolated from outbreaks of ...19852408304
isolation, characterization and possible mode of action of antiseminalplasmin, a new protein that inhibits the antimicrobial activity of seminalplasmin.the isolation from bovine seminal plasma and purification of a new protein called 'antiseminalplasmin', which reverses the inhibition of the growth of, and rna synthesis in, escherichia coli by seminalplasmin (another protein of bovine seminal plasma), is described. antiseminalplasmin, a weakly acidic protein, has a minimum mr of about 39 000 and appears to consist of three acidic peptide chains that move close to each other on electrophoresis on cellulose acetate strips or on sodium dodecyl sul ...19852408604
in vitro study of polymorphonuclear leukocyte damage to mammary tissues of lactating cows.effects of polymorphonuclear neutrophil leukocytes (pmn) on mammary tissue of lactating cows were studied in vitro. the pmn were isolated from mammary glands of nulliparous heifers given an injection of 5 micrograms of escherichia coli endotoxin. mammary tissue was obtained from noninfected quarters of 5 lactating holstein cows and was cultured in supplemented medium 199. mammary explants were treated by addition of intact or lysed pmn (10(5), 10(6), 10(7)/ml) or pmn (10(5), 10(7)/ml) which were ...19862421619
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