Publications
| Title | Abstract | Year Filter | PMID(sorted descending) Filter |
|---|
| 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 ... | 1989 | 2687989 |
| 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 ... | 1989 | 2684977 |
| etec-like strains from cattle. | 1989 | 2683340 | |
| 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 ... | 1989 | 2683337 |
| 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 ... | 1989 | 2681256 |
| 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 ... | 1989 | 2680987 |
| 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 ... | 1989 | 2679252 |
| [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 ... | 1989 | 2678591 |
| [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 ... | 1989 | 2678590 |
| [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 ... | 1989 | 2678588 |
| 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 ... | 1989 | 2674160 |
| 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- ... | 1989 | 2673828 |
| 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 ... | 1989 | 2673705 |
| 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 ... | 1989 | 2672915 |
| 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 ... | 1989 | 2672554 |
| 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 ... | 1989 | 2670166 |
| 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 ... | 1989 | 2663070 |
| 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 ... | 1989 | 2653954 |
| 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 ... | 1989 | 2650619 |
| 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 ... | 1989 | 2647798 |
| 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 ... | 1989 | 2644542 |
| 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 ... | 1989 | 2623085 |
| 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 ... | 1989 | 2592414 |
| 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. ... | 1989 | 2586346 |
| 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 ... | 1985 | 2580037 |
| 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 ... | 1985 | 2578457 |
| 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 ... | 1989 | 2567645 |
| 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 ... | 1989 | 2556133 |
| 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 ... | 1989 | 2552879 |
| 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 ... | 1989 | 2552037 |
| 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 ... | 1989 | 2551773 |
| studies on the binding substances on human erythrocytes for the heat-labile enterotoxin isolated from chicken enterotoxigenic escherichia coli. | to 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 ... | 1989 | 2547442 |
| 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 ... | 1989 | 2545441 |
| 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 ... | 1989 | 2542213 |
| 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 ... | 1989 | 2541640 |
| 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. | 1989 | 2541030 |
| 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 ... | 1989 | 2536676 |
| 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 ... | 1989 | 2532540 |
| 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 ... | 1989 | 2531681 |
| an improved system for expressing pancreatic ribonuclease in escherichia coli. | an 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. | 1989 | 2523320 |
| 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 ... | 1989 | 2500063 |
| 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 ... | 1989 | 2499888 |
| 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 ... | 1989 | 2496748 |
| 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 ... | 1989 | 2478555 |
| 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 ... | 1989 | 2478328 |
| 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 ... | 1988 | 2473163 |
| 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 ... | 1989 | 2467900 |
| 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 ... | 1988 | 2461943 |
| 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 ... | 1988 | 2460368 |
| 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 ... | 1988 | 2449362 |
| 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 ... | 1987 | 2448297 |
| 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. | 1987 | 2447751 |
| 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 ... | 1987 | 2446137 |
| 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 ... | 1987 | 2443451 |
| 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 ... | 1987 | 2442164 |
| 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 ... | 1987 | 2440861 |
| 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 ... | 1986 | 2431294 |
| 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 ... | 1986 | 2430793 |
| 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 ... | 1986 | 2423515 |
| 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 ... | 1986 | 2421619 |
| an enzyme-linked immunosorbent assay (elisa) for the measurement of antibodies to different parts of the gram-negative lipopolysaccharide core region. | bovine serum albumin was complexed with the core antigens of either escherichia coli j5 lps, salmonella minnesota r595 lps or e. coli lipid a. these core-bsa complexes were used for solid-phase coating in elisas for anti-core antibodies. antibodies, binding to various parts of the core region were easily quantified in a single experimental set-up, which was hitherto not possible. the elisa has only 3 incubation steps and is not costly as only moderate amounts of the core antigens (i.e., 1 microg ... | 1985 | 2413127 |
| 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 ... | 1985 | 2408604 |
| 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 ... | 1985 | 2408304 |
| 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 4.1.1.32) (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 ... | 1990 | 2407342 |
| 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 ... | 1990 | 2406717 |
| 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 ... | 1990 | 2406259 |
| 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 ... | 1990 | 2405755 |
| 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 ... | 1990 | 2404453 |
| 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. ... | 1990 | 2403535 |
| 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 ... | 1990 | 2341638 |
| 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 ... | 1990 | 2341175 |
| 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 ... | 1990 | 2332638 |
| 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 ... | 1990 | 2307186 |
| 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 ... | 1990 | 2302193 |
| 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 ... | 1990 | 2276697 |
| 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 ... | 1990 | 2273142 |
| 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 ... | 1990 | 2268293 |
| 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 ... | 1990 | 2268161 |
| 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 ... | 1990 | 2266972 |
| 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, ... | 1990 | 2261460 |
| 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 ... | 1990 | 2254332 |
| 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. | 1990 | 2218036 |
| the three-dimensional structure of recombinant bovine chymosin at 2.3 a resolution. | the crystal structure of recombinant bovine chymosin (ec 3.4.23.4; 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 ... | 1990 | 2217166 |
| protein stability and electrostatic interactions between solvent exposed charged side chains. | to 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 ... | 1990 | 2217161 |
| cellular requirements for anti-dna production induced in mice by immunization with bacterial dna. | to 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 ... | 1990 | 2209690 |
| 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 ... | 1990 | 2203759 |
| 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 ... | 1990 | 2201125 |
| 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 ... | 1990 | 2200514 |
| 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 ... | 1990 | 2200092 |
| 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 ... | 1990 | 2198287 |
| a statewide outbreak of escherichia coli o157:h7 infections in washington state. | in 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 ... | 1990 | 2196790 |
| 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 ... | 1990 | 2196415 |
| 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 ... | 1990 | 2195077 |
| 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 ... | 1990 | 2195031 |
| 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 ... | 1990 | 2191629 |
| 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 ... | 1990 | 2191044 |
| 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, ... | 1990 | 2189401 |
| 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 ... | 1990 | 2188979 |
| 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 ... | 1990 | 2184175 |
| 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 ... | 1990 | 2184174 |