production of native, correctly folded bovine pancreatic trypsin inhibitor by escherichia coli.a gene for bovine pancreatic trypsin inhibitor (bpti) was fused to the coding sequence for the escherichia coli alkaline phosphatase signal peptide and expressed in e. coli under the control of the alkaline phosphatase promoter. when induced in phosphate-depleted medium such cells produced a trypsin inhibitor that was indistinguishable from native, properly folded bpti. in particular, the bpti produced by e. coli had three disulfide bonds that appeared to be identical to those found in native bp ...19862423515
endothelial plasminogen activator inhibitor (pai): a new member of the serpin gene family.a human endothelial cdna expression library, based on the escherichia coli plasmid puc9, was screened with a heterologous antibody raised against purified bovine aortic endothelial plasminogen activator inhibitor (pai). a synthetic oligonucleotide, derived from a partial pai cdna expression clone, was used to select a full-length pai cdna, the size of which coincides with the length of pai mrna (approximately 2350 nucleotides) as determined by northern blot analysis. the authenticity of full-len ...19862430793
in vitro methylation of bovine papillomavirus alters its ability to transform mouse cells.bovine papillomavirus (bpv) was methylated in vitro at either the 29 hpaii sites, the 27 hhai sites, or both. methylation of the hpaii sites reduced transformation by the virus two- to sixfold, while methylation at hhai sites increased transformation two- to fourfold. dna methylated at both hpaii and hhai sites did not differ detectably from unmethylated dna in its efficiency of transformation. these results indicate that specific methylation sites, rather than the absolute level of methylated c ...19862431294
oligodeoxynucleotides containing synthetic abasic sites. model substrates for dna polymerases and apurinic/apyrimidinic endonucleases.a synthetic procedure has been developed by which stable abasic sites are introduced into oligodeoxynucleotides at any desired position in the sequence. a modified tetrahydrofuran moiety, isosteric with 2'-deoxyribofuranose, serves as a structural analog of the natural apurinic/apyrimidinic site. we have also prepared oligodeoxynucleotides that lack cyclic structure at the abasic site but retain the carbon atoms of the phosphodiester backbone. these synthetic oligodeoxynucleotides are cleaved on ...19872440861
enzymatic conversion of glutamate to delta-aminolevulinic acid in soluble extracts of euglena gracilis.glutamate was converted to the chlorophyll and heme precursor delta-aminolevulinic acid in soluble extracts of euglena gracilis. delta-aminolevulinic acid-forming activity depended on the presence of native enzyme, glutamate, atp, mg2+, nadph or nadh, and rna. the requirement for reduced pyridine nucleotide was observed only if, prior to incubation, the enzyme extract was filtered through activated carbon to remove firmly bound reductant. dithiothreitol was also required for activity after carbo ...19872442164
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
improved immunogenicity of a peptide epitope after fusion to hepatitis b core protein.synthetic vaccines for viral diseases can use defined regions of viral proteins as immunogens: the peptide sequence of amino acids 141-160 of the vp1 protein of foot and mouth disease virus (fmdv) elicits virus-neutralizing antibodies to protect guinea pigs, cattle and pigs either when coupled to a carrier protein or when administered in liposomes or in incomplete freund's adjuvant. the immune response to these peptides is much lower than that to complete virus particles and the same sequence fu ...19872446137
the influence of nalidixic acid on escherichia coli growth in milk.the high antibacterial activity of nalidixic acid against escherichia coli, cultivated in raw and pasteurized milk has been shown. the low oxygen reduction potential had no influence on the antibacterial activity of this drug. the natural antibacterial agents in active milk from an inflamed udder have reduced the efficacy of nalidixic acid inhibition of the growth of e. coli.19872447751
use of a series of ompf-ompc chimeric proteins for locating antigenic determinants recognized by monoclonal antibodies against the ompc and ompf proteins of the escherichia coli outer membrane.a method is presented for the efficient location of antigenic determinants using a series of chimeric proteins. by means of in vivo homologous recombination between the ompc and ompf genes coding for ompc and ompf, homologous proteins of the escherichia coli outer membrane, a series of ompf-ompc chimeric genes was constructed (nogami, t., mizuno, t., & mizushima, s. (1985) j. bacteriol. 164, 797-801, and this work). the ompf-ompc chimeric proteins expressed by these genes were successfully used ...19872448297
the influence of a double-stranded hindrance on dna synthesis performed by dna polymerase alpha, t4 dna polymerase, dna polymerase i (klenow fragment) and amv reverse transcriptase.the influence of a double-stranded region on dna synthesis performed by a series of dna polymerases on a single-stranded template was studied. two types of double-stranded hindrances were employed: a stable hairpin formed by the template alone and a region formed by the template and an extraneous oligonucleotide complementary to the template. while t4 and calf thymus alpha dna polymerases are strongly arrested at the beginning of either of the two double-stranded hindrances, the klenow fragment ...19882449362
inhibitory effect of flavonoids on dna-dependent dna and rna polymerases.flavonoids, (-)-epigallocatechin (1), myricetin (2) and quercetin (3), were investigated for inhibitory effects on e. coli dna polymerase i and t7 bacteriophage rna polymerase. in both dna and rna synthesis, 1 and 3 inhibited enzyme reactions by non-competitive and mixed type inhibition respectively, with regard to template dnas. myricetin (2) inhibited dna and rna polymerase reactions by mixed type and competitive type inhibition, respectively, with template dnas. it was suggested that 2 intera ...19882460368
monoclonal antibodies to a proenkephalin a fusion peptide synthesized in escherichia coli recognize novel proenkephalin a precursor forms.monoclonal antibodies have been generated to a chimeric peptide comprised of escherichia coli beta-galactosidase fused to the amino acid sequence 69-207 of human preproenkephalin a. two monoclonal antibodies, pe-1 and pe-2, were identified by their ability to recognize the same segment of proenkephalin a fused to the cii gene product of the e. coli bacteriophage lambda. the binding domains of pe-1 and pe-2 have been broadly located, with respect to the primary translation product, within the ami ...19882461943
secretory leukocyte protease inhibitor binding to mrna and dna as a possible cause of toxicity to escherichia coli.the expression of the positively charged human protein secretory leukocyte protease inhibitor (slpi) in escherichia coli causes severe cellular toxicity. after induction of slpi synthesis in a high-level-expression strain, sge61, the growth of the strain is arrested and total protein and rna synthesis rates decline by 60 to 70%. the mechanism of slpi-mediated inhibition of macromolecular synthesis was examined in cell-free transcription-translation systems. slpi proved to be a potent inhibitor o ...19892467900
molecular cloning of the plasmid-located determinants for cs1 and cs2 fimbriae of enterotoxigenic escherichia coli of serotype o6:k15:h16 of human origin.the plasmid pcs001, isolated from an enterotoxigenic strain of escherichia coli, mediates expression of the cs1 or cs2 and cs3 fimbrial adhesins in appropriate e. coli hosts. to characterize this further, hindiii-generated dna fragments of this plasmid were cloned into the vector plasmid pbr322. a chimaera, called pcs200, which mediated expression of the cs1 or cs2 fimbrial antigen but not of cs3 fimbrial antigen in appropriate host strains, was obtained. the dna inserted into the vector sequenc ...19882473163
iga subclasses of human colostral antibodies specific for microbial and food antigens.the distribution of total and antigen-specific iga1 and iga2 antibodies in human colostrum was determined by elisa using subclass-specific monoclonal reagents. in 18 samples of colostrum the mean ratio of total iga1 to iga2 was found to be 53:47, respectively, but significant individual variations were observed. in two samples we found unusually low levels of iga1, while iga2 was in the normal range. iga1 and iga2 antibody activities were determined against the following antigens: bovine gamma-g ...19892478328
cloning and characterization of cdna for mitochondrial gtp:amp phosphotransferase of bovine liver.three different types of cdna clones for mitochondrial gtp:amp phosphotransferase (ak3) were isolated from a cdna library of bovine liver poly(a)+ rna. nucleotide sequencing revealed that each of these clones consisted of a common 5'-untranslated region, a common ak3-coding sequence and a 3'-untranslated region with different sizes. by northern blot analysis, three species of ak3 mrna apparently corresponding to the isolated cdna clones were detected, which would be a result of varying terminati ...19892478555
g protein beta gamma subunits from bovine brain and retina: equivalent catalytic support of adp-ribosylation of alpha subunits by pertussis toxin but differential interactions with gs alpha.we have examined the ability of the beta gamma subunits of guanine nucleotide binding regulatory proteins (g proteins) to support the pertussis toxin (pt) catalyzed adp-ribosylation of g protein alpha subunits. substoichiometric amounts of the beta gamma complex purified from either bovine brain g proteins or the bovine retinal g protein, gt, are sufficient to support the adp-ribosylation of the alpha subunits of gi (the g protein that mediates inhibition of adenylyl cyclase) and go (a g protein ...19892496748
theileria annulata sporozoite surface antigen expressed in escherichia coli elicits neutralizing antibody.theileria annulata is an economically important protozoan parasite that threatens an estimated 250 million cattle with the disease tropical theileriosis. development of a defined subunit vaccine is one means of trying to develop control measures against the disease. to this end we have characterized a surface antigen complex of the infective stage (sporozoite), by using a monoclonal antibody that neutralizes sporozoite infectivity in vitro. we have cloned the gene coding for this complex and hav ...19892499888
reduction of protein mixed disulfides (dethiolation) by escherichia coli thioredoxin: a study with glycogen phosphorylase b and creatine kinase.the role of thioredoxin in the reduction of protein mixed disulfides (dethiolation) was studied by electrofocusing methodology with glycogen phosphorylase b and creatine kinase as substrates for the reaction. glycogen phosphorylase b was effectively dethiolated by escherichia coli thioredoxin with dithiothreitol as the reductant, while creatine kinase could not be dethiolated by this mechanism. the rate of dethiolation of phosphorylase b was dependent on the concentration of thioredoxin up to a ...19892500063
an improved system for expressing pancreatic ribonuclease in escherichia improved method for expressing and purifying bovine pancreatic ribonuclease from a synthetic gene using the lambda promoter controlled by a temperature-sensitive repressor is described. the procedure involves isolation in the presence of a refolding buffer containing oxidized and reduced glutathione, under conditions where rnase can refold, but where proteases presumably do not. yields are approx. 2 mg purified protein per 1 ferment.19892523320
inhibition of the first phosphodiester bond formation catalyzed by escherichia coli rna polymerase in the presence of bovine seminal plasmin: promoter dependency.inhibition of the abortive initiation of transcription catalyzed by e. coli rna polymerase has been studied here in the presence of bovine seminal plasmin. seminal plasmin, which is known to be a stronger inhibitor than rifampicin binds at the same site as rifampicin to rna polymerase. however, unlike rifampicin, seminal plasmin showed the inhibition of the formation of both the first and second phosphodiester bonds. we observed, in vitro, that the degree of inhibition of transcription was diffe ...19892531681
expression of cdnas encoding wild-type and mutant neuromodulins in escherichia coli: comparison with the native protein from bovine brain.murine cdna that encodes neuromodulin, a neurospecific calmodulin binding protein, was inserted into the plasmid pkk223-3 for expression in escherichia coli. after being transformed into e. coli strain sg20252 (lon-), the expression vector directed the synthesis of a protein that was recognized by polyclonal antibodies raised against bovine neuromodulin. the recombinant protein expressed in e. coli was found to be tightly associated with insoluble cell material and was extractable only with guan ...19892532540
fragments of prochymosin produced in escherichia coli form insoluble inclusion bodies.bovine prochymosin produced in escherichia coli has been used as a model system to investigate factors which may cause a recombinant protein to accumulate as insoluble inclusion bodies. a series of plasmids was constructed to investigate the effect of deletions within the prochymosin-coding sequence on protein inclusion body formation. the results demonstrated that as much as 70% of the prochymosin-coding sequence could be deleted with no significant reduction in the accumulation of insoluble pr ...19892536676
bacterial expression of the p24 gag protein of the bovine leukaemia virus.the possibility of expression of the gag gene of bovine leukaemia virus (blv) in the bacterial system was investigated. the dna fragment coding for the gag core 24 kda protein of blv was inserted into the porf1 expression vector. the polypeptides expressed in e. coli were analysed by western blotting. the bacterially synthesized antigens were detected by the serum of a blv-infected cow and by mouse monoclonal antibodies against the native p24 gag protein.19892541030
alterations in bovine neutrophil function during the periparturient period.neutrophils from 8 holstein heifers were evaluated for function during the periparturient period. random migration, ingestion of bacteria, superoxide anion production, native (nonenhanced) chemiluminescence, iodination, and antibody-dependent, cell-mediated cytotoxicity by neutrophils were determined. foremilk samples were evaluated for bacteria. significant (p less than 0.05) increases in random migration of neutrophils, iodination, and chemiluminescence were evident 2 weeks before parturition ...19892541640
antimicrobial activity of clove oil dispersed in a concentrated sugar solution.essential oil of clove, dispersed (0.4% v/v) in a concentrated sugar solution, had a marked germicidal effect against various bacteria and candida albicans. staphylococcus aureus (five strains), klebsiella pneumoniae, pseudomonas aeruginosa, clostridium perfringens, and escherichia coli inoculated at a level of 10(7) cfu/ml, and c. albicans (inoculum 4.0 x 10(5) cfu/ml) were killed (greater than 99.999%) after 2-7 min in a laboratory broth supplemented with 63% (v/w) of sugar, and containing 0.4 ...19892542213
a c-terminal domain of gap is sufficient to stimulate ras p21 gtpase activity.the cdna for bovine ras p21 gtpase activating protein (gap) has been cloned and the 1044 amino acid polypeptide encoded by the clone has been shown to bind the gtp complexes of both normal and oncogenic harvey (ha) ras p21. to identify the regions of gap critical for the catalytic stimulation of ras p21 gtpase activity, a series of truncated forms of gap protein were expressed in escherichia coli. the c-terminal 343 amino acids of gap (residues 702-1044) were observed to bind ha ras p21-gtp and ...19892545441
studies on the binding substances on human erythrocytes for the heat-labile enterotoxin isolated from chicken enterotoxigenic escherichia study the predominant binding substance for the heat-labile enterotoxin (ltc) isolated from chicken enterotoxigenic escherichia coli, competitive binding assays were performed with neuraminidase-treated human type b erythrocytes and 125i-labeled b subunit of ltc (ltc-b). of all inhibitors used, the ganglioside gm1 was the most effective in inhibiting the binding of 125i-labeled ltc-b to the erythrocytes. the other gangliosides used as inhibitors, gangliosides gd1b, gd1a, gm2, gt1b and gm3, we ...19892547442
high yield synthesis of the bovine leukemia virus (blv) p24 major internal protein in saccharomyces cerevisiae.bovine leukemia virus (blv) p24 gene was expressed in saccharomyces cerevisiae under the control of the pho5 (encoding repressible acid phosphatase, rapase) promoter. yeast cells were transformed by a yeast-e. coli shuttle vector carrying the pho5 promoter, the p24 gene and the cyc1 transcription terminator. after low inorganic phosphate (pi) induction of the pho5 promoter, p24 accumulated in the producing cells up to a concentration representing 10% of total soluble proteins. the expression lev ...19892551773
arpp-21, a cyclic amp-regulated phosphoprotein enriched in dopamine-innervated brain regions. ii. molecular cloning and nucleotide sequence.a cdna clone for the mrna of bovine arpp-21 (camp-regulated phosphoprotein, mr = 21,000 as determined by sds-page) was isolated from a modified okayama-berg plasmid library. transformed escherichia coli colonies were screened by in situ colony hybridization with 2 different oligonucleotide probes derived from the amino acid sequence of the bovine protein. sequence analysis of the longest cdna clone, ptkai [2407 nucleotides plus a poly(a) tail], revealed a 267-nucleotide-long coding region in agr ...19892552037
modulation of the cellular immune responses to t-cell-dependent and t cell-independent antigens in lambs with induced bovine viral diarrhea virus infection.functional interaction between lymphoid cells and lymphotropic viruses is particularly evident for bovine viral diarrhea virus (bvdv) in cattle and its closely related virus, the border disease virus (bvdv) in sheep. the most important aspect of acute or chronic phases of bvdv or bdv infection was the host's increased susceptibility to secondary bacterial or viral infection. to study the ability of bvdv to alter the development of the cellular immune responses to concomitant inoculation with t c ...19892552879
electron transfer facilitated by superoxide dismutase: a model for membrane redox systems?membranes, which are an amalgam of proteins and lipids, effect electron transfer through largely unknown mechanisms. using albumin with bound fatty acids as a model, we have investigated the possible role of these two membrane constituents in electron transfer. in the presence of albumin: fatty acid, there is substantial enhancement of the reduction of ferricytochrome c by ferrous iron. to assess the possible role of free superoxide in cytochrome c reduction, we added mammalian copper/zinc conta ...19892556133
bacteroides-specific igg and iga subclass antibody-secreting cells isolated from chronically inflamed gingival tissues.the emergence of cells that produce igg and iga subclass antibodies to bacteroides gingivalis (porphyromonas gingivalis) fimbriae and lipopolysaccharide (lps) antigens was examined in mononuclear cells isolated from inflamed gingiva of different stages (slight, moderate or advanced) of adult periodontitis (ap). antigen-specific igm, igg (including igg1, igg2, igg3 and igg4) and iga (including iga1 and iga2) producing cells were enumerated by the elispot assay and were compared with total ig-prod ...19892567645
antigen-antibody interaction. the immunodominant region of edp208 pili.the edp208 pilus contains a major antigenic determinant in the n-terminal dodecapeptide, as shown by e. a. worobec, a. k. taneja, r. s. hodges, and w. paranchych ((1983) j. bacteriol. 153, 955-961). this peptide was chemically synthesized, coupled to bovine serum albumin with n-hydroxysuccinimidyl p-azido-benzoate, and used in immunoblot and enzyme-linked immunosorbent assays to show it was capable of reacting with anti-edp208 pilus antibodies. antibodies raised against the synthetic peptide con ...19852578457
gal-gal pyelonephritis escherichia coli pili linear immunogenic and antigenic epitopes.the linear immunogenic and antigenic structure of e. coli gal-gal pili from the recombinant strain hu 849 was investigated with nine synthetic peptides corresponding to regions of the pilus sequence predicted to contain hydrophilic beta-turns. five peptides, as bovine serum albumin conjugates, were found by anti-hu 849 pilus serum and were thus designated "immunogenic epitopes." peptides corresponding to r 25-38, r 38-50, and r 48-61 (which jointly comprise the single intramolecular disulfide lo ...19852580037
a possible correlation between histological changes in regional subcutaneous tissue induced by bacterial lipopolysaccharides and their adjuvant activities.previously it was demonstrated that klebsiella pneumoniae o3 lipopolysaccharide (ko3 lps) exhibited much stronger adjuvant action on antibody response to subcutaneously (s.c.) injected sheep red blood cells or deaggregated bovine serum albumin than did other kinds of lps, the r-form lps lacking the o-specific polysaccharide chain of ko3 lps (r-lps), and the lipid a fractionated from ko3 lps. we compared histological changes in the regional subcutaneous tissues of mice injected subcutaneously (s. ...19892586346
neurite extension and neuronal survival activities of recombinant s100 beta proteins that differ in the content and position of cysteine residues.s100 beta produced in escherichia coli from a synthetic gene (van eldik, l. j., j. l. staecker, and f. winningham-major. 1988. j. biol. chem. 263:7830-7837) stimulates neurite outgrowth and enhances cell maintenance in cultures of embryonic chick cerebral cortex neurons. in control experiments, the neurite extension activity is reduced by preincubation with antibodies made against bovine brain s100 beta. when either of the two cysteines in s100 beta are altered by site-directed mutagenesis, the ...19892592414
conserved dna sequences in chlamydial plasmids.two 7.4-kb plasmids from chlamydia psittaci have been cloned and characterized. these plasmids are quite distinct from the 6.2-kb c. psittaci and the c. trachomatis plasmids when compared by restriction endonuclease analysis. the plasmids show considerable cross-hybridization, with only a small region highly conserved and identified as a 4 x 22-bp tandemly repeated region. this sequence is identical in the two size categories of c. psittaci plasmids and differs from c. trachomatis plasmids by on ...19892623085
peptidyl-prolyl cis-trans isomerase is the cyclosporin a-binding protein cyclophilin.peptidyl-prolyl cis-trans isomerase (ppiase) catalyses the cis-trans isomerization of proline imidic peptide bonds in oligopeptides and has been shown to accelerate the refolding of several proteins in vitro. its activity has been detected in yeast, insects and escherichia coli as well as in mammals, and it is though to be essential for protein folding during protein synthesis in the cell. we purified ppiase from pig kidney and found that its amino-acid sequence is identical to that reported for ...19892644542
effect of steroidal anti-inflammatory drugs on escherichia coli endotoxin-induced mastitis in the cow.effects of intramammary infusion of prednisolone (40 mg) or intramuscular injection of dexamethasone (30 mg) or flumethasone (5 mg) on local and systemic signs in escherichia coli endotoxin-induced mastitis were studied. the effect of varying intervals (0, 2, and 4 h) between intramammary infusion of endotoxin and prednisolone in the same quarter was determined. intramammary infusion of endotoxin (.01 mg lipopolysaccharide of e. coli) produced inflammation of the infused quarter, fever, tachycar ...19892647798
enzyme-capture assay for rapid detection of escherichia coli in oysters.enzyme-capture assays (ecas) for escherichia coli beta-d-glucuronidase (gud) were performed directly from 24-h gas-positive lauryl tryptose broth (ltb) fermentation tubes that had been inoculated with oyster homogenate seeded with e. coli. the ltb-eca method yielded results in 1 day that were equivalent to those obtained in 2 days by an ltb and ec-4-methylumbelliferyl-beta-d-glucuronide (ec-mug) method. overall, 62 of 64 (97%) positive ec-mug broths from which e. coli was isolated were correctly ...19892650619
hemagglutinating activity of the b subunit(s) of the heat-labile enterotoxin isolated from chicken enterotoxigenic escherichia coli.the hemagglutinating activity of the b subunit(s) of the heat-labile enterotoxin (ltc-b) produced by chicken enterotoxigenic escherichia coli was studied by hemagglutination and hemagglutination inhibition. no or weak hemagglutination of intact human erythrocytes was found by the ltc-b at the highest concentration used, whereas strong hemagglutination of both neuraminidase- and pronase-treated human erythrocytes was found. enhancement in hemagglutination of treated human erythrocytes induced by ...19892653954
picosecond tryptophan fluorescence of thioredoxin: evidence for discrete species in slow exchange.the steady-state tryptophan fluorescence and time-resolved tryptophan fluorescence of escherichia coli thioredoxin, calf thymus thioredoxin, and yeast thioredoxin have been studied. in all proteins, the tryptophan residues undergo strong static and dynamic quenching, probably due to charge-transfer interactions with the nearby sulfur atoms of the active cysteines. the use of a high-resolution photon counting instrument, with a time response of 60 ps full width at half-maximum, allowed the detect ...19892663070
prevention of clinical coliform mastitis in dairy cows by a mutant escherichia coli vaccine.a prospective cohort study was undertaken in two commercial california dairies. the treatment group, 246 cows, received three doses of a whole cell bacterin of j5 escherichia coli (mutant of e. coli o111:b4) plus freund's incomplete adjuvant vaccine (two in the dry period and one after calving) while 240 unvaccinated cows served as controls. thirty-five cases of clinical coliform mastitis were diagnosed, six in vaccinated cows and 29 in unvaccinated cows. bacteria isolated from the clinical case ...19892670166
detection of conglutinin in bovine serum by complement-dependent agglutination of escherichia coli.agglutination of escherichia coli (eca) by normal bovine serum was shown to be prevented by heating serum to 56 degrees c for 30 min, but restored by normal horse, swine, rabbit or guinea pig sera. further investigation of the eca reaction using techniques to distinguish between conglutination and immunoconglutination indicated eca to be a conglutination reaction. testing of 264 sera obtained from 22 normal cattle over a period of 5 months did not show individual or seasonal variation in eca. ch ...19892672554
rapid decay of serum igg recognizing gram-negative cell wall core antigens in neonatal calves.serum immunoglobulins of the igg isotype recognizing common gram-negative cell core epitopes were serially measured, using a direct elisa, on samples obtained from 20 neonatal holstein calves. an r-mutant escherichia coli (strain j5) was used as a plate antigen in this assay. total serum igg concentration was measured using radial immunodiffusion. half-lives of core antigen-specific igg (7.56 days) and total serum igg (22.66 days) were dramatically different (p less than 0.0005). this may be an ...19892672915
expression of bovine cytochrome p450c17 cdna in saccharomyces cerevisiae.we constructed expression plasmids for bovine adrenal cytochrome p450c17 (p450c17) by inserting the corresponding cdna between the yeast alcohol dehydrogenase i promoter and terminator of the expression vector paah5. plasmids pa alpha 1 and pa alpha 2 contained the entire coding region for bovine p450c17, whereas pac alpha 1 included the cdna coding for chimeric p450c alpha consisting of the amino-terminal 45 amino acid residues of rat p450c and the carboxy-terminal 482 amino acid residues of bo ...19892673705
properties of vero cytotoxin-producing escherichia coli of human and animal origin belonging to serotypes other than o157:h7.eight non-o157:h7 vero cytotoxin (vt)-producing escherichia coli (vtec) strains isolated from ill persons and nine bovine and lamb strains of serogroups matching the human strains, were characterized for various properties known to be associated with e. coli virulence. five different serogroups were represented: o5, o55, o103, o111 and o153. the bovine and lamb strains produced vt1, while 3 human strains produced vt1, 3 produced vt2 and 2 were positive for both vt1 and vt2. the strains were non- ...19892673828
phospholipase a2 engineering: design, synthesis, and expression of a gene for bovine (pro)phospholipase a2.a gene coding for the (pro)phospholipase a2 (pla2) from bovine pancreas has been designed, synthesized, and expressed in escherichia coli. the gene was designed with a variety of restriction sites that will facilitate future mutagenesis studies. codons occurring frequently in prokaryotic systems were chosen whenever possible. the total gene spans 404 base pairs and was divided into 33 oligonucleotides. the gene was constructed in two halves of 224 and 180 base pairs from the oligonucleotides by ...19892674160
[escherichia coli mastitis in cattle. i. clinical diagnosis and epidemiological aspects].the diagnostic aspects, incidence, risk factors and prevention of coliform mastitis are reviewed in the present paper. it is concluded that it is not possible to establish an accurate diagnosis of coliform mastitis, which is based on a specific clinical symptom differentiating it from other forms of mastitis. not any single symptom or combination of symptoms is specific for coliform mastitis. the importance of coliform mastitis in dairy cattle showed a marked increase during the last few decades ...19892678588
[escherichia coli mastitis in cattle. ii. pathogenesis and symptomatic therapy].the pathogenesis, course run by the disease, and symptomatic treatment of mastitis due to escherichia coli in dairy cattle are reviewed in relation to the functioning of cellular and humoral defence mechanisms. the systemic symptoms of disease during mastitis caused by e. coli are attributed to the release and subsequent absorption from the udder of endogenous inflammatory mediators, rather than the direct absorption of endotoxins into the circulation. the course run by the disease during mastit ...19892678590
[escherichia coli mastitis in cattle. iii. antibacterial therapy].this review paper is concerned with antibacterial therapy of mastitis caused by escherichia coli. the choice of an antibacterial agent is discussed, and nine criteria are referred to, on which this choice should be based. in the second part possible forms of antibacterial treatment are discussed. literature on parenteral and local treatment of mastitis due to e. coli is scarcely available. the evaluation of antibacterial drugs is mainly based on mic values and pharmacokinetic studies in normal a ...19892678591
pharmacokinetics of ceftazidime given alone and combination with probenecid to unweaned calves.ceftazidime pharmacokinetic values were studied in unweaned calves given the antibiotic alone or in combination with probenecid. ceftazidime was administered iv to 9 calves at a dosage of 10 mg/kg of body weight and im (10 mg/kg) to 8 calves, to 7 calves (10 mg/kg plus probenecid [40 mg/kg]), and to 9 calves (10 mg/kg plus probenecid [80 mg/kg]). serum concentration-vs-time data were analyzed, using noncompartmental methods based on statistical moment theory. the data for iv ceftazidime administ ...19892679252
cloning and expression of the pasteurella multocida toxin gene, toxa, in escherichia coli.a chromosomal dna library of a toxigenic type d strain of pasteurella multocida subsp. multocida was established in escherichia coli. from this library two clones, spe308 and spe312, were identified by using a monoclonal antibody against the osteoclast-stimulating p. multocida toxin (pmt). extracts of these clones showed cytopathic activity identical to that of extracts of toxigenic p. multocida. the recombinant plasmids, pspe308 and pspe312, directed the synthesis of a protein with an apparent ...19892680987
close association of verotoxin (shiga-like toxin) production with enterohemolysin production in strains of escherichia coli.sixty-four verotoxin-producing (vt+) escherichia coli strains were analyzed for vt1- and vt2-specific dna sequences and for production of hemolysin. strains of human origin were of the following serotypes: o157:h7 or h-, o111:h8 or h-, o26:h11, o114:h4, and rough:h7. strains of serotypes o157:h7, o113:h21, o116:h21, and rough:h- were from cattle, while those of serotype o139:k12:h1 were from pigs. all 64 isolates carried either vt1 or vt2 or both genes. sixty of the strains (93.8%) were hemolyti ...19892681256
occurrence of 'attaching and effacing' lesions in the small intestine of calves experimentally infected with bovine isolates of verocytotoxic e coli.nine calves (five colostrum-fed, four colostrum-deprived) were challenged with two field strains of escherichia coli which produced either verocytotoxin 1 (vt1) or verocytotoxin 2 (vt2). although three colostrum-fed calves had blood and mucus in their faeces, no diarrhoea was observed. three of the four colostrum-deprived calves had diarrhoea and in two of them severe lesions were detected in the small intestine. focal changes were detected in the colon of three calves. e coli were associated wi ...19892683337
etec-like strains from cattle. 19892683340
glutaredoxin from rabbit bone marrow. purification, characterization, and amino acid sequence determined by tandem mass spectrometry.a glutaredoxin was purified from rabbit bone marrow, and its amino acid sequence was determined by high performance tandem mass spectrometry. the sequences of peptides generated by digestion with trypsin alone or in combination with thermolysin were determined from their collision-induced dissociation (cid) mass spectra. alignment of these sequences and additional sequence information were obtained from the collision-induced dissociation mass spectra of peptides obtained from digestion of the in ...19892684977
haematological changes in buffalo calves inoculated with escherichia coli endotoxin and corticosteroids.haematological studies were conducted on 10 clinically normal water buffalo calves to determine leucocytic responses to escherichia coli endotoxin, prednisolone and dexamethasone. intravenous injection of 10 micrograms endotoxin induced minimal decreases in leucocyte numbers, whereas 20, 50 and 100 micrograms produced a marked leucopenia within one hour. moderate to marked leucopenia, neutropenia and lymphopenia persisted for three to 14 hours. significant rebound neutrophilia was evident at six ...19892687989
hemagglutination, hydrophobicity, enterotoxigenicity, and drug-resistance characteristics of avian escherichia coli.a total of 35 escherichia coli isolates obtained from necropsy materials of hens with septicemia in the konya region of turkey were examined for hemagglutination (ha), cell-surface hydrophobicity, enterotoxigenicity, and drug resistance. ha tests were performed on live cultures with human (group a), bovine, avian (chicken), and guinea pig erythrocytes with and without mannose. nine ha patterns were observed. of the 35 isolates, 62.8% exhibited mannose sensitive hemagglutination (msha), 8.6% exhi ...19892695047
production of monoclonal antibodies toward bovine interferons-alpha suitable for immunopurification.five murine hybridoma clones, producing monoclonal antibodies (mabs) to bovine interferon-alpha (boifn-alpha) were established. one of these, f12, secreted mabs giving high titers, in elisa tests, neutralizing both boifn-alpha, -alpha c, and boifn-alpha d activities, belonging to the mouse igg1 class, and having a binding affinity constant of 10(8) m-1. f12 mabs were used for immunoaffinity purification of boifn-alpha, and recombinant boifn-alpha c from escherichia coli extracts was purified to ...19892715671
a covalent angiogenin/ribonuclease hybrid with a fourth disulfide bond generated by regional mutagenesis.human angiogenin is a blood vessel inducing protein whose primary structure displays 33% identity to that of bovine pancreatic ribonuclease a (rnase a). angiogenin catalyzes limited cleavage of 18s and 28s ribosomal rna and is several orders of magnitude less potent than rnase a toward conventional substrates. a striking structural difference between angiogenin and rnase is the virtual absence of sequence similarity within the region of rnase that contains the cys-65--cys-72 disulfide bond. inde ...19892719939
combined immunodeficiency in a calf.combined immunodeficiency was documented in a 6-week-old angus calf. the calf had lymphopenia, undetectable serum igm or iga, and low concentrations of serum igg (420 mg/dl). the calf was treated for diarrhea, pneumonia, and shock, and was given antimicrobial drugs, fluids, and plasma. the calf died of systemic candidiasis and escherichia coli bacteremia. aggregated lymphatic folliculi (peyer patches), lymph nodes, and thymic and splenic lymphoid tissue could not be identified at necropsy.19892768060
purification, composition, and activity of two bactenecins, antibacterial peptides of bovine neutrophils.extracts of granules of bovine neutrophils are known to exhibit a marked antibacterial activity in vitro. by a simple, two-step chromatographic procedure, we have resolved two peptide components of the antibacterial system. they were named bac-5 and bac-7 from the general term bactenecin and had molecular masses of about 5 and 7 kilodaltons, respectively. over 45 and 20% of the amino acid residues in the two bactenecins are proline and arginine, respectively. the remaining amino acids are mainly ...19892777377
bovine mitochondrial protein synthesis elongation factors. identification and initial characterization of an elongation factor tu-elongation factor ts complex.animal mitochondrial protein synthesis factors elongation factor (ef) tu and ef-ts have been purified as an ef-tu.ts complex from crude extracts of bovine liver mitochondria. the mitochondrial complex has been purified 10,000-fold to near homogeneity by a combination of chromatographic procedures including high performance liquid chromatography. the mitochondrial ef-tu.ts complex is very stable and cannot be dissociated even in the presence of high concentrations of guanine nucleotides. no guani ...19892808417
high levels of circulating neutralizing antibody in normal animals to recombinant mouse interferon-beta produced in yeast.plasma from normal outbred swiss mice not previously given interferon (ifn) neutralized a glycosylated (high-mannose) recombinant murine ifn-beta made in yeast (rmuifn-beta y). the neutralization antibody titers were as high as 1:6,000 versus rmuifn-beta y, whereas the titers obtained with native murine ifn-beta (muifn-beta) were 100-fold less; a recombinant murine ifn-beta make in escherichia coli (rmuifn-beta ec) was not neutralized at 1:10 dilution of plasma. an elisa using rmuifn-beta y demo ...19892809279
non-oxidative antibacterial activity of bovine neutrophil granule proteins towards mastitis pathogens.acid extracts of bovine neutrophil granules displayed potent antibacterial activity towards a number of mastitis pathogens in vitro. killing of pathogens by acid extractable granule protein was dependent on incubation time, protein concentration, bacterial cell load, ph and ionic strength. gram-negative and gram-positive organisms showed variable sensitivity to granule extract. strains of staphylococcus aureus were the most resistant of tested organisms to granule extract. gram-negative organism ...19892816175
nucleotide sequence and expression in escherichia coli of the gene encoding the nonstructural protein ncvp2 of bovine rotavirus.cloned dna copy of rotavirus genome segment 5 from bovine rotavirus rf strain has been used to determine the nucleotide sequence of the gene that encodes for the nonstructural viral protein ncvp2. the sequence data indicated that segment 5 consists of 1581 base pairs and is a + t rich (66%). the positive strand of segment 5 contains a single open reading frame that extends 491 codons and possesses 5'- and 3'-terminal untranslated regions of 32 and 73 base pairs, respectively. the first aug confo ...19872823457
expression and accurate processing of yeast penta-ubiquitin in escherichia expression vector (psjyub-5) was constructed which contained five repeats of the "yeast ubiquitin gene" regulated by a heat-inducible lambda pl promoter. the vector, when expressed in escherichia coli, produced a penta-ubiquitin of approximately 42 kda. purified penta-ubiquitin was found to be as active as the human mono-ubiquitin in the in vitro atp/ubiquitin-dependent proteolytic assay of the reticulocyte lysate, indicating that the expressed gene product was recognized by the enzymes invol ...19872826431
enteric infections in veal calves: a longitudinal study on four veal calf units.forty-five calves on four veal calf units were monitored during the first four weeks after their arrival. faecal samples were collected on alternate days and screened for the presence of rotaviruses, bovine coronavirus, cryptosporidium oocysts, k99 positive strains of e. coli and salmonella spp. rotaviruses and cryptosporidium were the most commonly detected agents (78% and 60% respectively of the calves). bovine coronavirus was detected in the faeces of 18% of the calves, whilst k99 positive e. ...19872827367
illegitimate recombination mediated by calf thymus dna topoisomerase ii in vitro.we have found that purified calf thymus dna topoisomerase ii mediates recombination between two phage lambda dna molecules in an in vitro system. the enzyme mainly produced a linear monomer recombinant dna that can be packaged in vitro. novobiocin and anti-calf thymus dna topoisomerase ii antibody inhibit this atp-dependent recombination. the recombinant molecules contain duplications or deletions, and most crossovers take place between nonhomologous sequences of lambda dna, as judged by the seq ...19882832845
functional mapping of the human papillomavirus type 11 transcriptional enhancer and its interaction with the trans-acting e2 proteins.the transcriptional enhancer sequences of the papillomaviruses are regulated by trans-acting factors encoded by the viral e2 open reading frame. we have performed detailed functional and physical analyses of the enhancer of the human papillomavirus type 11 (hpv-11). using the chloramphenicol acetyltransferase (cat) assay in transiently transfected monkey cv-1 cells, the enhancer region has been localized to a 270-bp tract immediately preceding the e6 open reading frame, and it consists of two fu ...19882833426
colonization of the streptomycin-treated mouse large intestine by a human fecal escherichia coli strain: role of adhesion to mucosal receptors.escherichia coli f-18, a normal fecal isolate, was previously shown to be an excellent colonizer of the streptomycin-treated cd-1 mouse large intestine, whereas e. coli f-18col-, a derivative of e. coli f-18 that no longer makes the e. coli f-18 colicin, was shown to be a poor mouse colonizer. it was also shown that e. coli f-18 bound two to three times more soluble colonic mucus protein than did e. coli f-18col- and that a major receptor in cd-1 mouse colonic mucus was a 50.5-kilodalton glycopr ...19882833441
bovine seminalplasmin [corrected] is a dna unwinding protein.the duplex dna unwinding ability of seminalplasmin [corrected] from bovine semen was examined by treatment of plasmid-protein complexes with calf thymus topoisomerase i and resolution of the topoisomer distributions by agarose gel electrophoresis. binding of seminalplasmin [corrected] results in a moderate degree of unwinding of supercoiled plasmid. the elongation of the rna chain by e. coli rna polymerase over promoter containing template is not inhibited by seminalplasmin [corrected]. however, ...19882834234
conservation of primary structure in the lipoyl-bearing and dihydrolipoyl dehydrogenase binding domains of mammalian branched-chain alpha-keto acid dehydrogenase complex: molecular cloning of human and bovine transacylase (e2) cdnas.the subunit structures and conservation of the dihydrolipoyl transacylase (e2) components of bovine and human branched-chain alpha-keto acid dehydrogenase complexes were investigated by western blotting, peptide sequencing, and cdna cloning methods. rabbit antiserum prepared against the sodium dodecyl sulfate (sds) denaturated bovine e2 subunit recognized the inner e2 core, and the first hinge region of the e2 chain, but failed to react with the lipoyl-bearing domain as determined by western blo ...19882837277
nonradioactive labeling of synthetic oligonucleotide probes with terminal deoxynucleotidyl transferase.synthetic oligonucleotides were tailed at the 3' end using terminal deoxynucleotidyl transferase. nucleotide triphosphates with free primary amines at the end of side chains were compared for their tailing efficiency and/or detection sensitivity, using biotin-11-dutp as a reference. free primary amines were tagged with activated biotin or fluorescein isothiocyanate. the probes were then detected with either streptavidin-alkaline phosphatase complex or anti-fluorescein antibodies and alkaline pho ...19882837921
site-specific dna recombination in mammalian cells by the cre recombinase of bacteriophage p1.the cre protein encoded by the coliphage p1 is a 38-kda protein that efficiently promotes both intra- and intermolecular synapsis and recombination of dna both in escherichia coli and in vitro. recombination occurs at a specific site, called lox, and does not require any other protein factors. the cre protein is shown here also to be able to cause synapsis of dna and site-specific recombination in a mammalian cell line. a stable mouse cell line was established that expresses the cre protein unde ...19882839833
comparison of the bovine herpesvirus 1 gi gene and the herpes simplex virus type 1 gb a previous report, we localized the gene for a 130-kilodalton envelope glycoprotein (gi) of bovine herpesvirus 1 (bhv-1) to a 3.6-kilobase hpai-kpni restriction endonuclease fragment from the long unique region of the bhv-1 genome (map position 0.405 to 0.432) and showed that a herpes simplex virus 1 (hsv-1) glycoprotein b (gb) probe uniquely hybridized to this bhv-1 restriction fragment. here we present the complete nucleotide sequence of the bhv-1 gi gene and the predicted 932-amino-acid se ...19882841484
electron-transfer complexes of ascaris suum muscle mitochondria. iii. composition and fumarate reductase activity of complex ii.complex ii of the anaerobic respiratory chain in ascaris muscle mitochondria showed a high fumarate reductase activity when reduced methyl viologen was used as the electron donor. the maximum activity was 49 mumol/min per mg protein, which is much higher than that of the mammalian counterpart. the mitochondria of ascaris-fertilized eggs, which require oxygen for its development, also showed fumarate reductase activity with a specific activity intermediate between those of adult ascaris and mamma ...19882843227
activation of ada protein as a transcriptional regulator by direct alkylation with methylating agents.the adaptive response is a cellular process to induce dna repair enzymes in response to a challenge of alkylating agents. in this process ada protein, the product of the ada gene, plays a major role; it accepts the methyl groups of the methylated dna at the cysteine residues of its own molecule, and the methylated form of ada protein promotes transcription of its own gene, thereby triggering induction of the whole process. in addition to this dna-mediated activation of ada protein, we have propo ...19882843522
polymorphonuclear leucocyte dysfunction during short term metabolic changes from normo- to hyperglycemia in type 1 (insulin dependent) diabetic patients.polymorphonuclear leucocyte (pmn) ingestion of particles coated with lipopolysaccharide (lps) from escherichia coli was compared to other pmn functions in seven patients with insulin dependent diabetes mellitus (iddm) during short-term controlled metabolic changes from normo- to hyperglycemia without ketoacidosis. factors known to interfere with pmn functions were excluded. pmn ingestion of particles coated with both lps and bovine serum albumin became reduced from normo- to hyperglycemia. pmn m ...19882846445
diphosphonates are potent inhibitors of mammalian inorganic pyrophosphatase.methanediphosphonate and 12 analogs thereof with different substituents at the carbon atom are potent competitive inhibitors of highly purified rat liver and bovine heart inorganic pyrophosphatases. the inhibition constants for the most effective diphosphonates, which contain an nh2 or oh group at the bridge carbon atom, are in the micromolar range. yeast and escherichia coli pyrophosphatases are markedly less sensitive to the diphosphonates. pyrophosphatase inhibition may be related to the nume ...19882848451
a model of acute infectious neonatal diarrhoea.oral inoculation of neonatal mfi mice with enterotoxigenic strains of escherichia coli that possessed the k99 or f41 antigen or both resulted in severe diarrhoea with high mortality. the diarrhoea was associated with increased fluid in the gut, greatly increased numbers of e. coli in gut homogenates and reduced weight gain compared to control animals. further studies with strain b44 demonstrated greatly increased numbers of e. coli on the surface of the intestinal mucosa and haemo-concentration. ...19872856846
the action of alpha-ketoglutarate dehydrogenase on 4-chloronitrosobenzene: evidence for species-dependent differences in active site properties.the reaction of bovine (bos taurus) and porcine (sus scrufa) cardiac alpha-ketoglutarate dehydrogenase complex (alpha-kgd) with 4-chloronitrosobenzene (i) was shown to produce a hydroxamic acid (iv) and a product due to a bamberger rearrangement as previously shown for escherichia coli alpha-kgd. the conversion of i into an active site-bound electrophile was general among the three alpha-kgd enzymes tested, but quantitative differences in products and kinetics were shown. the reaction of i was s ...19852858339
[synthesis and cloning of dna complementary to mrna of the bovine mammary gland].poly(a+)mrna from bovine mammary glands was used to synthesize double-stranded cdnas that were subsequently inserted into the plasmid vector pbr322 at the pst1 site by means of oligo(dg)-oligo(dc) tailing. after transfection of escherichia coli jc5183, recombinant plasmid library containing 5400 clones was screened by serial rounds of colony hybridization in situ to total [23p] poly(a+)mrna and electrophoretically homogenious [32p]16smrna of mammary glands. then hybrid selection of mrna and subs ...19852859232
arylsulphatase a and acid phosphatase activities in plasma and leucocytes during lps fever in the ox (bos taurus).intravenous injection of e. coli lps (0.5 micrograms/kg) produced the biphasic elevation of rectal temperature (tr) in conscious oxen. the fever was accompanied by a significant increase of the arylsulphatase a (asa) activities in plasma and in mononuclear leucocytes. in polymorphonuclear cells a substantial decrease of the asa activity after 1 hr fever was observed. after 3.5 hr of fever the polymorphonuclear activity of asa restored to normal found before lps administration. in contrast with a ...19852859950
inactivation of escherichia coli glutamine synthetase by xanthine oxidase, nicotinate hydroxylase, horseradish peroxidase, or glucose oxidase: effects of ferredoxin, putidaredoxin, and menadione.previous studies have shown that several mixed-function oxidation (mfo) systems are capable of catalyzing the inactivation of glutamine synthetase (gs) [r.l. levine, c. n. oliver, r. m. fulks, and e. r. stadtman (1978) proc. natl. acad. sci. usa 78, 2120-2124] and a number of the other enzymes [l. fucci, c. n. oliver, m. j. coon, and e. r. stadtman (1983) proc. natl. acad. sci. usa 80, 1521-1525]. it has now been found that in the presence of fe(iii), o2, and an appropriate electron donor (hypox ...19852860872
[frequency of fy and k99 pili in strains of escherichia coli isolated from diarrheal calves in france].epidemiological study of bovine e. coli shows that the fy e. coli pilus which has previously been described and is also known as att25, can be found in 30 of 415 fecal samples of diarrheic calves, eight of them carrying both fy and k99 pili. the k99 e. coli pilus is present in 86 fecal samples. strains carrying both fy and k99 pili account for 9% of k99 enterotoxigenic e. coli. k99-, fy+ e. coli do not produce the thermostable enterotoxin (tsa). k99+, fy- or k99+, fy+ e. coli are present mainly ...19852861785
[anti-k99 vaccination and colostric protection of calves infected experimentally with escherichia coli k99].colostral antibodies of cows vaccinated with e. coli b41 (o101: k99, f41) protect completely b41 experimentally infected calves. in order to know more precisely the role of k99, f41 antibodies in protection, calves receiving the colostrum of b41 vaccinated cows are infected with e. coli b44 (o9: k30: h-k99, f41). vaccination multiplies k99 antibodies in colostrum by seven. in b44 infected calves, specific k99, f41 antibodies protect only 3 out of 6 calves completely. additive effect of antibodie ...19852861786
the use of [3h]aniline to identify the essential carboxyl group in the bovine mitochondrial f1-atpase that reacts with 1-(ethoxycarbonyl)-2-ethoxy-1,2-dihydroquinoline.the inactivation of the bovine heart mitochondrial f1-atpase with 1-(ethoxycarbonyl)-2-ethoxy-1,2-dihydroquinoline (eedq) in the presence of [3h]aniline at ph 7.0 led to the covalent incorporation of 3h into the enzyme. when the atpase was inactivated by 94% with 0.9 mm eedq in the presence of 3.6 mm [3h]aniline in a large-scale experiment in which the protein concentration was 21 mg/ml, 4.2 mol [3h]anilide were formed per mol enzyme, of which 0.35 mol was incorporated per mol of the alpha subun ...19852862844
expression of human terminal deoxynucleotidyl transferase in escherichia coli.a cloned dna fragment related to pt17 containing a partial cdna sequence of human terminal deoxynucleotidyl transferase was used as a probe to screen for the full length cdna sequence of the enzyme in a lambda gt11 library constructed from human lymphoblastoid km-3 cdna. a recombinant containing a 2068-base pair insert was isolated and recloned into the ecori site of the sequencing plasmic puc-8 as two subclones, pt711 and pt106. dna sequencing and hybridization studies showed that pt711 contain ...19852863268
high performance liquid chromatography purification and amino terminal sequence analysis of the subunits of bovine heart mitochondrial f1-atpase.all five subunits of bovine heart mitochondrial f1-atpase have been isolated by reverse-phase hplc and nh2-terminal sequences determined by gas phase edman degradations. bovine gamma exhibits 16 identities in the first 30 residues compared with the nh2-terminus of gamma from e.coli f1. bovine delta exhibit about 27% identity with residues 28-59 of precursor delta from n.crassa and in the first six residues is identical with delta from s.cerevisiae. approximately half of bovine epsilon has been s ...19852864928
additive protective effects of colostral antipili antibodies in calves experimentally infected with enterotoxigenic escherichia coli.with oral infection of calves by an enterotoxigenic escherichia coli strain carrying k99, f41, and fy adhesins, colostrums from cows vaccinated against either k99+f41 or fy did not provide protection, but a mixture of the two colostrums did. the association of antibodies directed against the different adhesins is more effective than antibodies directed against one adhesin alone for colostral protection against enterotoxigenic e. coli carrying several adhesins.19852866162
isolation of escherichia coli o157:h7 from dairy cattle associated with two cases of haemolytic uraemic syndrome. 19862877210
stimulation of human polymorphonuclear leukocyte oxidative metabolism by type 1 pili from escherichia coli.we compared the degree to which escherichia coli phase variants which do (t1p+ e. coli) or do not (t1p- e. coli) express type 1 pili (t1p) stimulate human polymorphonuclear leukocyte (pmn) oxidative activity. unopsonized t1p+ e. coli stimulated the release of 0.20 to 0.24 nmol of h2o2 per 10(6) pmn per min and the consumption of 1.4 to 4.0 nmol of o2 per 10(6) pmn per min; no measurable pmn oxidative activity was stimulated by unopsonized t1p- e. coli. in the presence of serum opsonins, t1p+ e. ...19872880806
f41 pili as protective antigens of enterotoxigenic escherichia coli that produce f41, k99, or both pilus antigens.pigs suckling dams that have been vaccinated with pilus antigen are protected against challenge with enterotoxigenic escherichia coli (etec) strains that express the same pilus antigen. however, some etec strains express more than one pilus antigen. pregnant swine were vaccinated either with e. coli hb101 that harbored a recombinant plasmid coding for f41 expression (f41+) or with the hb101 parent strain that carries the phc79 vector (f41-). suckling pigs born to vaccinated dams were challenged ...19872880807
monoclonal antibody passive hemagglutination and capture enzyme-linked immunosorbent assays for direct detection and quantitation of f41 and k99 fimbrial antigens in enterotoxigenic escherichia coli.production of diarrhea in neonatal calves by enterotoxigenic escherichia coli depends on its ability to attach to the epithelial cells of the intestine via surface adhesins called pili or fimbriae and to secrete enterotoxins. the most important of these fimbriae are designated k99 and f41. we produced and characterized a murine monoclonal antibody specific to f41. this monoclonal antibody and a k99-specific monoclonal antibody were used to develop sensitive and specific passive hemagglutination ...19872880866
receptor-specific agglutination tests for detection of bacteria that bind globoseries glycolipids.specific binding to the globoseries of glycolipid receptors explains the adherence of uropathogenic escherichia coli to host cells. the minimal receptor disaccharide gal alpha 1----4gal beta [galactose alpha (1----4)galactose beta] is recognized by most attaching clinical isolates. however, wild-type isolates can express adhesins with several different receptor specificities. bioassays do not permit separate analysis of each receptor specificity, since the target cells contain multiple potential ...19872880867
cattle as reservoir of verotoxin-producing escherichia coli o157:h7. 19872886741
incidence and some characteristics of fimbriae fy and 31a of escherichia coli isolates from calves with diarrhea in japan.escherichia coli isolates from calves with diarrhea (1 day to 8 weeks old, 140 individuals) were surveyed for the three immunologically distinct fimbrial adhesins fy, 31a, and k99. of a total of 1,370 strains isolated, 96 (7.0%), 34 (2.5%), 75 (5.5%), and 13 (0.9%) were identified as fy+, 31a+, fy+.31a+, and k99+, respectively. the k99+ strains also manifested heat-stable enterotoxin production (st+), while fy+, 31a+, and fy+.31a+ strains were st-. expression of fy and 31a was repressed at lower ...19872889130
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