| [possibility of fortifying milk nutrient mixtures for children with lactoglobulin against e. coli and proteus]. | sweet milk nutrient mixtures, biologically active additives (baa) and lactic acid ferments, intended for child nutrition, were enriched with the immune preparation lactoglobulin against e. coli and proteus. serological and immunochemical investigations of hemagglutinating activity and other characteristics of lactoglobulin in the enriched milk mixtures and baa evidenced that the preparation retained its full value during the technological process and in the period of storage. no signs of lactogl ... | 1986 | 3541377 |
| recombinant-dna-derived bovine growth hormone from escherichia coli. 1. demonstration that the hormone is expressed in reduced form, and isolation of the hormone in oxidized, native form. | the isolation of bacterially synthesized, recombinant-dna-derived, bovine growth hormone (r-bgh) with native structure is described. the r-bgh is found in insoluble form, in a pellet fraction, after cell breakage and centrifugation. cell envelope components (protein, lipid, endotoxin) and nucleic acids are selectively removed from the pellet fraction by an edta/lysozyme/deoxycholate extraction. we demonstrate that the r-bgh is largely reduced until solubilized using 6 m guanidine/hcl. air oxidat ... | 1987 | 3545831 |
| campylobacter jejuni in dairy cows and raw milk. | twelve herds of dairy cows were examined by rectal swabbing for the presence of campylobacter jejuni. ten herds were positive with the incidence of colonized animals ranging from 10 to 72% of those tested. with the exception of the two negative herds where mains water only was consumed, all animals drank from rivers or streams when grazing. there was no relationship between total and coliform counts and the presence of c. jejuni in raw milk. however, milk from one farm that consistently gave pos ... | 1987 | 3595744 |
| characterization of tryptophan environments in glutamate dehydrogenases from temperature-dependent phosphorescence. | tryptophan room temperature phosphorescence in solution was detected in glutamic dehydrogenase from bovine liver and escherichia coli with lifetimes of 1.2 and 0.65 s, respectively. although these enzymes possess three and five tryptophanyl residues per polypeptide chain, respectively, the temperature dependence of the phosphorescence quantum yield estimates that the room temperature emission is due, in either case, to a single residue. long triplet-state lifetimes and very small rates of o2 que ... | 1987 | 3663638 |
| specificity of o6-alkylguanine-dna alkyltransferase. | extensive investigations of the specificity of o6-alkylguanine-dna alkyltransferase (aat) have been carried out. these studies have shown that: (i) the mammalian protein differs from that of escherichia coli in lacking the ability to remove methyl groups from o4-methylthymine; (ii) the protein can remove longer alkyl groups from the o6 position but the rate of repair declines as the chain length increases; (iii) o6-methylguanine in rna is much less active as a substrate for the protein than o6-m ... | 1987 | 3679391 |
| expression of a pseudogene for interferon-alpha l. | the human leukocyte interferon-alpha l (ifn-alpha l) appears to be a pseudogene because it contains a termination codon in the dna coding for the precursor peptide (signal peptide), but the remainder of the gene codes for an interferon protein of normal length. to determine if this gene codes for an active interferon molecule, an expression plasmid was constructed for ifn-alpha l that was produced in escherichia coli. the ifn-alpha l is active on human and bovine cells, and exhibits a trace of a ... | 1987 | 3681016 |
| human and bovine milk: comparison of ganglioside composition and enterotoxin-inhibitory activity. | milk gangliosides inhibit vibrio cholerae enterotoxin and escherichia coli heat-labile enterotoxin. human milk gangliosides showed considerably higher enterotoxin-inhibitory activity compared to bovine and formula milk gangliosides as measured in vitro by enzyme-linked immunosorbent assay and in vivo in rabbit small bowel loops. while gangliosides from less than 1 ml human milk inhibited 0.1 microgram choleratoxin in vitro and in vivo, five to 10 times higher amounts of bovine milk gangliosides ... | 1986 | 3714350 |
| modification of bovine heart succinate dehydrogenase with ethoxyformic anhydride and rose bengal: evidence for essential histidyl residues protectable by substrates. | purified and membrane-bound succinate dehydrogenase (sdh) from bovine heart mitochondria was inhibited by the histidine-modifying reagents ethoxyformic anhydride (efa) and rose bengal in the presence of light. succinate and competitive inhibitors protected against inhibition, and decreased the number of histidyl residues modified by efa. the essential residue modified by efa was not the essential thiol of sdh, but modification of the essential thiol abolished the protective effect of malonate ag ... | 1986 | 3717948 |
| aetiology of diarrhoea in young calves. | faeces samples were collected from 302 untreated calves on the day of onset of diarrhoea and from 49 healthy calves at 32 farms experiencing outbreaks of diarrhoea. at least four diarrhoeic calves were sampled on each farm, and samples were examined for rotavirus, coronavirus, cryptosporidium, enterotoxigenic escherichia coli and salmonella species. although all these enteropathogens were excreted more frequently by the diarrhoeic than by the healthy calves, the difference was significant overal ... | 1986 | 3750766 |
| dexamethasone-induced attenuation of cardiopulmonary dysfunction in endotoxemic calves. | effects of dexamethasone on pulmonary hemodynamics, pulmonary mechanics, and gas exchange were determined in anesthetized (pentobarbital sodium) and paralyzed (pancuronium bromide) calves (9.4 +/- 0.4 weeks old) during 5 hours of endotoxemia. escherichia coli endotoxin (055-b5) was infused iv at 20 micrograms/kg the 1st hour, followed by a continuous infusion at 10 micrograms/kg/hour for the following 4 hours. dexamethasone (5 mg/kg) was given iv 18 hours and 1 hour before endotoxin administrati ... | 1986 | 3777644 |
| [etiology and chemotherapy of suppurative surgical infection in horses and cattle]. | a total of 24 horses and 42 cattle with a variety of local suppurative processes (wounds, abscesses, phlegmons, tendovaginitis, etc.) were studied under conditions of the clinic with regard to the most commonly found microbial species and the opportunity to work out antibioticogrammes in terms of the effectiveness of 11 of the chemotherapeutic agents widely used in the practice. it was found that prevailing in horses were staphylococci and streptococci. in cattle corynebacterium pyogenes was pre ... | 1986 | 3811221 |
| cryptosporidium among children with acute diarrhoea in the west of ireland. | during a period of 12 months beginning on 18 february 1985, 1246 specimens of faeces from 935 children aged 3 weeks to 12 years with acute diarrhoea of varying severity were examined for the presence of cryptosporidium oocysts. twenty-six patients required admission to hospital; four of them needed intravenous rehydration. predominant clinical features were diarrhoea, often watery, and vomiting. diarrhoea varied in duration between 7-15 days. cryptosporidium oocysts were found in specimens from ... | 1987 | 3819459 |
| c1q, a subunit of the first component of complement, enhances binding of plasma fibronectin to bacteria. | the interaction of plasma fibronectin with c1q of the complement system has been demonstrated in the past several years. in addition, the antibody-independent binding of c1q to bacteria, as well as the binding of plasma fibronectin to bacteria, is well documented. this study examines whether the binding of c1q to bacteria enhances the interaction of c1q and bacteria with plasma fibronectin. highly purified 125i-c1q bound to several species of bacteria in the absence of antibody. the binding of 1 ... | 1985 | 3875560 |
| production of neutralizing monoclonal antibodies to escherichia coli heat-stable enterotoxin. | in an effort to develop new approaches to the study and control of infectious diarrhea, we prepared murine monoclonal antibodies to the escherichia coli heat-stable enterotoxin (sta). the toxin was purified from e. coli culture media and conjugated to bovine serum albumin. the sta-bovine serum albumin conjugate was used to immunize balb/c mice, and the immune spleen cells from these mice were fused with sp2/0 myeloma cells. resultant hybridomas were screened in an enzyme-linked immunosorbent ass ... | 1985 | 3880723 |
| channeling of a beta-oxidation intermediate on the large subunit of the fatty acid oxidation complex from escherichia coli. | the kinetic properties of the fatty acid oxidation complex from escherichia coli were studied with the aim of elucidating the functional consequence of having enoyl-coa hydratase and 3-hydroxyacyl-coa dehydrogenase associated with a multifunctional polypeptide. the kinetic parameters of individual enzymes were determined and used in model calculations based on a published theory (storer, a. c., and cornish-bowden, a. (1974) biochem. j. 141, 205-209) to predict the kinetic behavior of a system of ... | 1985 | 3882701 |
| the ecology of escherichia coli in market calves fed a milk-substitute diet. | dynamic changes in the escherichia coli population in the calf gut were studied over 21 days in a group of 18 intensively-reared market calves. isolates were identified by o-serogrouping, biotyping and resistogram patterns. seventy o-serogroups were identified among nearly 3000 e. coli isolates examined and these were subdivided into 416 strains by means of their biotype and resistogram. seventy-five per cent of these strains were detected only once or twice, which points to the continual replac ... | 1985 | 3884561 |
| an assessment of bacteroides fragilis group organisms as indicators of human faecal pollution. | membrane filtration techniques were used to enumerate bacteroides fragilis group (bfg) organisms and escherichia coli in a variety of natural waters, the influents and effluents from three types of sewage treatment plants and faeces of various animals. the results suggest that bfg organisms die off more rapidly than e. coli in water and that animal faeces are not a significant source of bfg. it is suggested that the ratio of bfg to e. coli in water may be used to indicate the proximity of a sour ... | 1985 | 3884562 |
| the ecology of escherichia coli in calves reared as dairy-cow replacements. | a continual turn-over in the strains forming the majority of faecal escherichia coli flora was demonstrated in 16 calves reared as dairy cow replacements. the incidence of antibiotic resistance among isolates, as measured by an antibiotic resistance index (ari), changed markedly with the age of the calf. the value was low initially, when the calves were 1-2 days old and housed with adult animals. it then rose rapidly during the first week after the animals had been weaned and moved into nursery ... | 1985 | 3884563 |
| rapid kinetics of ca2+-induced fusion of phosphatidylserine/phosphatidylethanolamine vesicles. the effect of bilayer curvature on leakage. | we have employed both small unilamellar vesicles (suv) and large unilamellar vesicles formed by the reverse phase evaporation technique (rev) to study the initial kinetics of membrane aggregation and fusion. stopped flow measurements of the calcium-induced changes in the turbidity of suv and rev, formed from 1:1 (mol/mol) mixtures of bovine phosphatidylserine (ps) and escherichia coli phosphatidylethanolamine (pe), were used to follow particle aggregation. simultaneous measurements of the fluore ... | 1985 | 3884605 |
| linkage of genes for heat-stable enterotoxin, drug resistance, k99 antigen, and colicin in bovine and porcine strains of enterotoxigenic escherichia coli. | linkages among genes for production of escherichia coli heat-stable enterotoxin (st), drug resistance, k99 antigen, and colicin were investigated in 2 bovine and 3 porcine strains of enterotoxigenic e coli. in conjugation experiments, all 5 isolates transferred enterotoxigenicity and the ability to produce k99; 4 of the 5 isolates also transferred antibiotic resistance markers, and 3 colicinogenic strains transmitted the ability to produce colicin. in 2 of the 3 colicin-producing strains, the ge ... | 1985 | 3888010 |
| trna-rrna sequence homologies: evidence for an ancient modular format shared by trnas and rrnas. | homologies between trnas and rrnas are identified in searches using various combinations of escherichia coli, yeast, halobacterium volcanii and bovine mitochondrial sequences. as in previously reported comparisons, the homologies are too frequent and long to be attributed to coincidence, and similar frequencies from inter- and intraspecies comparisons preclude evolutionary convergence as an explanation. in contrast to the earlier studies, patterns in the positioning of the homologies are now des ... | 1985 | 3888302 |
| characterization of the coliform and enteric bacilli in the environment of calves with colibacillosis. | in the first part of the present study the coliform and enteric bacilli in the environment of calves with colibacillosis were examined. the occurrence, number, and pathogenic properties of escherichia coli in barnyard soils were obtained from six cattle ranches. the o and k serogroups of e. coli isolates obtained from the feces of calves with colibacillosis born at these cattle ranches were determined, and their serotypes were compared with the e. coli o and k serotypes found in soils. the resul ... | 1985 | 3890744 |
| efficient expression in escherichia coli of two species of human interferon-alpha and their hybrid molecules. | a new type of interferon (ifn)-alpha cdna (ifn-alpha i') was identified in a cdna library constructed from namalva cells infected with sendai virus. the nucleotide sequence of this cdna showed homology, with the exception of two nucleotides in the coding region, with the previously identified ifn-alpha i gene (lawn et al., 1981). an expression plasmid which directs the synthesis of the mature ifn-alpha i' peptide was constructed using vectors carrying the lpp/lac promoter and "runaway" replicon. ... | 1985 | 3891272 |
| chorismate mutase-prephenate dehydrogenase from escherichia coli: cooperative effects and inhibition by l-tyrosine. | the effects of a variety of structural analogs of l-tyrosine on the mutase and dehydrogenase activities of hydroxyphenylpyruvate synthase have been investigated. from these studies it is concluded that the alpha-nh3+ alpha-coo-, and the 4-oh groups are essential for binding of l-tyrosine as an inhibitor of the dehydrogenase and that the l configuration is also essential. dixon plots for inhibition of the dehydrogenase activity by some of these analogs were nonlinear and could be described by a v ... | 1985 | 3896148 |
| effect of prepartum vaccination with k99 escherichia coli vaccine on maternal and calf blood antibody concentration and calf health. | one hundred and two dry, pregnant holstein cows were identified alternately as vaccinated or nonvaccinated (group 0) animals. vaccinated cows were scheduled for vaccination at 6 and 3 wk prior to expected calving date with vicogen, a commercial vaccine produced for the prevention of calf scours caused by enteropathogenic escherichia coli that possess the k99 antigen. group 1 included cows that were less than 6 wk from freshening when the experiment started and, therefore, received only one vacci ... | 1985 | 3897306 |
| in vivo proteolytic activity of the mammary gland. contribution to the origin of secretory component, beta 2-microglobulin and bovine-associated mucoprotein (bamp) in cows milk. | milk samples were collected from holstein-friesian cows at various times after milking (10-30 min; 30 min-10 hr) and treated with a protease inhibitor or control solution. samples were then fractionated into whole, skimmed and cell-free skimmed milk aliquots. some animals were treated with e. coli endotoxin prior to sample collection. the concentrations of three membrane-associated proteins (map), beta 2-microglobulin (beta 2m), secretory component (sc) and bovine-associated mucoprotein (bamp) a ... | 1985 | 3898552 |
| [enzyme constellation of the blood plasma in the prognosis of decreased adaptability in newborn calves]. | the dynamic was studied of the enzyme activity of che, aph, ald, goat, gpt, ldg, and cph in 30 newborn calves. fifteen of the animals developed coli bacteriosis later on. blood was sampled at the 6th to 24th hour as well as on the 5th day following birth. at the 6th hour che, aph, ald, and cph of the diseased calves showed lower activity as against the enzyme activity of the unaffected animals. similar trend was noticed also at the 24th hour. contrary to the other enzymes of the constellation th ... | 1985 | 3898561 |
| cloning of a bovine interferon-alpha gene subfamily and comparisons between genetically engineered and leukocyte bovine interferons. | bovine peripheral leukocytes were virally induced for interferon production, and an acid stable, sds stable, antiviral activity was detected in the preparation. this bovine interferon (boifn) was tested for its ability to induce an antiviral state in various mammalian cells and was found to be specific to cells from bovine origin. the boifn cross reacts with antibodies against human ifn-alpha but these antibodies do not neutralize the bovine ifn activity. leukocyte boifn exhibits polymorphism up ... | 1985 | 3899795 |
| [identification of bacterial clones that encode cow's caseins by direct immunological screening of the cdna library]. | a sensitive immunoassay was used to identify recombinant dna plasmids carrying cdna fragments of bovine caseins in the cdna library from rrna of bovine mammary glands. colonies grown on nitrocellulose filters were lysed in situ and proteins from the lysates were blotted onto cnbr-activated filter paper. antigens covalently bound to the cnbr-activated paper or bound to the nitrocellulose filters were detected by reaction with antiserum to caseins, followed by 125i-labeled protein a from staphyloc ... | 1985 | 3900695 |
| induction of dna strand breaks by rsu-1069, a nitroimidazole-aziridine radiosensitizer. role of binding of both unreduced and radiation-reduced forms to dna, in vitro. | [2-14c]-rsu-1069 [1-(2-nitro-1-imidazolyl)-3-(1-aziridino)-2-propanol], either as a parent (unreduced) or following radiation reduction, binds to calf thymus dna in vitro. radiation-reduced rsu-1069 binds to a greater extent and more rapidly than the parent compound. rsu-1137, a nonaziridino analogue of rsu-1069, binds following radiation reduction. radiation-reduced misonidazole (1-(2-nitro-1-imidazolyl)-3-methoxy-2-propanol) exhibits binding ratios a thousand-fold less than those of reduced rs ... | 1985 | 3902026 |
| single amino acid substitutions at conserved residues of human interferon-alpha can effect antiviral specific activity. | site-specific in vitro mutagenesis was used to direct various amino acid substitutions at conserved positions within the sequence of human interferon-alpha 1 (ifn-alpha 1). the antiviral specific activity of ifn-alpha 1, expressed in m13 as a fusion protein [ifn-alpha 1 (phi wt)], could be altered by single amino acid substitutions. the substitution of glycine for tyrosine at position 123 results in a loss of more than 99% of the antiviral specific activity on human cells, but causes no signific ... | 1985 | 3904757 |
| cloning and expression of the leukotoxin gene of pasteurella haemolytica a1 in escherichia coli k-12. | a clone bank of pasteurella haemolytica a1 was constructed by partial digestion of the genomic dna with sau3a and ligation of 5- to 10-kilobase-pair fragments into the bamhi site of the plasmid vector pbr322. after transformation into escherichia coli k-12, a total of 4 x 10(3) recombinant clones was obtained. these were screened for the production of p. haemolytica soluble antigens by a colony enzyme-linked immunosorbent assay blot method with a rabbit antiserum raised against the soluble antig ... | 1985 | 3905610 |
| arabinosylnucleoside 5'-triphosphate inhibits dna primase of calf thymus. | it has been shown that dna primase activity is tightly associated with 10s dna polymerase alpha from calf thymus and that the ribonucleotide-dependent dna synthesis is more sensitive to aractp than dna-primed dna synthesis (yoshida, s., et al. (1983) biochim. biophys. acta 741, 348-357). here we measured dna primase activity using poly(dt) template or m13 bacteriophage single-stranded dna template and primer rna synthesis was coupled to the reaction by escherichia coli dna polymerase i klenow fr ... | 1985 | 3905783 |
| synthesis and biochemical characterization of a photoactivatable, iodinatable, cleavable bacterial lipopolysaccharide derivative. | a method for the synthesis of a photoactivatable, iodinatable, and thiol-cleavable derivative of bacterial lipopolysaccharide (lps) is described using sulfosuccinimidyl 2-(p-azidosalicylamido)-1,3'-dithiopropionate. the method described is applicable to lps from both smooth and rough bacteria. evidence is presented that the coupling reaction occurs primarily to phosphoethanolamine residues localized to the inner core region of the lps. radioiodination of the derivatized lps results in a product ... | 1985 | 3905790 |
| septicemic colibacillosis and failure of passive transfer of colostral immunoglobulin in calves. | septicemic colibacillosis is a highly fatal disease that occurs in calves less than 2 weeks of age. the disease occurs when a calf that fails to absorb protective levels of immunoglobulin from colostrum is exposed to an invasive serotype of e. coli. management to ensure good passive transfer of colostral immunoglobulin will prevent this disease and reduce calf mortality caused by other infectious diseases as well. | 1985 | 3907781 |
| effect of iron on serotypes and haemagglutination patterns of escherichia coli in bottle-fed infants. | strains of escherichia coli isolated from faecal specimens of ten infants receiving breast milk, six receiving a cow-milk preparation with iron supplement (5 mg/l) and six the preparation without iron supplement (less than 0.5 mg/l), were serotyped and examined for their haemagglutinating activity. the escherichia coli flora of breast-fed and bottle-fed infants consisted of one resident strain, accompanied by one or more transient strains. changes in the serotype of the escherichia coli flora an ... | 1985 | 3912179 |
| [characterization of strains of escherichia coli isolated from calves with neonatal diarrhea]. | thirty fecal samples of diarrheic calves from a beef herd with previous history of neonatal diarrhea were cultured for isolation of escherichia coli k99 (+) and for enterotoxigenic tests. the age distribution of sampled calves was: 1 animal less than 6 days old, 21 between 7-15 days old and 8 between 16-30 days old. although most strains were classified as isaacson et al (16) biotype four, they were negative for detection of k99 antigen by slide agglutination test. the assay for heat-stable (st) ... | 1985 | 3916646 |
| examination of calf prochymosin accumulation in escherichia coli: disulphide linkages are a structural component of prochymosin-containing inclusion bodies. | recent reports have shown that synthesis of certain recombinant proteins in escherichia coli results in the production of intracellular inclusion bodies. these studies have not analyzed the structure of the inclusion body especially regarding the intermolecular forces holding it together. we have examined structural aspects of inclusion bodies made in e. coli as a result of high level expression of the eukaryotic protein, calf prochymosin. prochymosin is a monomeric protein containing three disu ... | 1985 | 3924595 |
| arachidonic acid metabolites in milk of cows during acute coliform mastitis. | concentrations of prostaglandin f2 alpha (pgf2 alpha) and thromboxane b2 (txb2) were evaluated in the milk of cows with naturally occurring (n = 3) and experimentally induced (n = 5) acute coliform mastitis. these arachidonic acid metabolites were measured by radioimmunoassay in unextracted milk. experimental infections were induced by inoculating 600 to 1,200 colony-forming units of escherichia coli into 1 mammary quarter per experimental cow. in the experimental cows, milk was collected before ... | 1985 | 3927804 |
| beta-sulfur substituted alpha-ketoglutarates as inhibitors and alternate substrates for isocitrate dehydrogenases and certain other enzymes. | the rs-isomers of beta-mercapto-alpha-ketoglutarate, beta-methylmercapto-alpha-ketoglutarate and beta-methylmercapto-alpha-hydroxyglutarate have been synthesized. beta-mercapto-alpha-ketoglutarate was a potent inhibitor, competitive with isocitrate and noncompetitive with nadp+, of the mitochondrial nadp-specific isozyme from pig heart (ki = 5 nm; km (dl-isocitrate)/ki(rs-beta-mercapto-alpha-ketoglutarate) = 650) and pig liver, the cytosolic isozyme from pig liver (i0.5 = 23 nm), and the nadp-li ... | 1986 | 3947094 |
| clinical pharmacology of apramycin in calves. | the minimal inhibitory concentrations (mic) of apramycin, a unique aminocyclitol antibiotic, were compared with the mic of dihydrostreptomycin and neomycin for 323 salmonella, 178 escherichia coli and twenty-six pasteurella multocida isolates recovered from newborn calves. apramycin exhibited better in vitro anti-bacterial activity than dihydrostreptomycin and neomycin; isolates of salmonella group b and e. coli resistant to the latter were sensitive to apramycin. the two-compartment open model ... | 1985 | 3989905 |
| the influence of murine macrophage-conditioned medium on cloning efficiency, antibody synthesis, and growth rate of hybridomas. | murine b-cell hybridomas made with the p3x63-ag8.653 myeloma showed increases in cloning efficiency and efficiency of growth in hypoxanthine-aminopterin-thymidine (hat) medium of 50-100-fold in the presence of medium conditioned by primary mouse peritoneal macrophages (mcm). similar effects were elicited by mcm from 3 continuous macrophage lines. the j774a.1 line conditioned the medium as efficiently as primary macrophages without induction. conditioning by the p388d1 line was several-fold less ... | 1985 | 3998479 |
| antigenic relationships in mammalian dna polymerase. | rabbit antibody was prepared against a high-molecular-weight dna polymerase purified from the soluble fraction of calf thymus gland. this antibody does not inhibit terminal deoxynucleotidyl transferase isolated from that source, but does inhibit both low-molecular-weight and high-molecular-weight dna polymerases isolated from cytoplasmic and nuclear fractions of a number of mammalian tissues (mouse l cells, calf thymus, phytohemagglutinin-stimulated human lymphocytes, rat liver, and rabbit bone ... | 1972 | 4110484 |
| a technique for ultracryotomy of cell suspensions and tissues. | ultracryotomy of fixed tissue has been investigated for a number of years but, so far, success has been limited for several reasons. the simple technique herein reported allows the ultracryotomy not only of a variety of tissues but also of single cells in suspension, with a preservation and visualization of ultrastructural detail at least equivalent to that obtained with conventional embedding procedures. in this technique, sucrose is infused into glutaraldehyde-fixed tissue pieces before freezi ... | 1973 | 4121290 |
| modification of rna polymerase after t3 phage infection of escherichia coli b. | e. coli b cells infected with t3 phage contain a modified host rna polymerase in addition to the normal rna polymerase found in uninfected cells. the modified rna polymerase behaves differently in its elution properties from the normal enzyme on deae-cellulose, phosphocellulose, and dna-cellulose column chromatography. the modified enzyme also differs from the normal polymerase in some of its enzymatic parameters. the specific activity of the modified rna polymerase is markedly lower (i.e., (1/4 ... | 1973 | 4126728 |
| herd incidence of bovine mastitis in four danish dairy districts. i. the prevalence and mastitogenic effect of micro-organisms in the mammary glands of cows. | | 1974 | 4213559 |
| escherichia coli agglutinins in cow serum, colostrum and the nursing calf. | immunochemical properties of escherichia coli o antibodies present in bovine serum and colostrum were investigated. dam and calf serum samples plus colostral whey samples were fractionated by gel filtration, and the 7s and 19s fractions isolated. antibody activity against the o antigens of four recognized e. coli bovine pathogens was determined by the indirect hemagglutination test on the whole serum and colostral whey samples and the 7s and 19s fractions thereof. mercaptoethanol reduction was u ... | 1970 | 4248443 |
| [r factors in strains of pathogenic enterobacteria isolated from domestic animals and particularly from dogs]. | strains of enterobacteria (nine escherichia coli and two salmonella) isolated from primary or secondary infections in the dog, cat, pig, calf and kangaroo were studied for the presence of extrachromosomal drug resistance factors (r factors). seven strains of e. coli and two strains of salmonella transferred resistance involving the following antibiotics: streptomycin, ampicillin, chloramphenicol, neomycin and tetracycline. all strains harboring r factors transferred streptomycin resistance and t ... | 1972 | 4258542 |
| studies on the chick-lethal toxin of eecherichia coli. | a toxin which is lethal for two week old chicks has been recovered from strains of escherichia coli o78:k80 of bovine and avian origin and from avian isolates of serogroups o2, o45 and o109. the toxin is heat-labile, antigenic, high in protein, inactivated by pronase, trypsin, amylase, and pancreatic lipase. the toxin may be precipitated by ammonium sulfate or tca treatment from the supernatant obtained by repeated centrifugation of sonicated cells. considerable purification has been obtained by ... | 1973 | 4270809 |
| the hygiene and marketing of fresh cream as assessed by the methylene blue test. a report by a working party to the director of the public health laboratory service. | the hygiene and marketing of fresh cream in england and wales was investigated by a working party of the public health laboratory service (phls) between 1 october 1968 and 31 july 1969. thirty-one cream-producing dairies were visited and observations made in the light of the code of practice published by the milk and milk products technical advisory committee of the ministry of agriculture, fisheries and food, and the scottish home and health department. suggestions are made in this report to st ... | 1971 | 4326247 |
| electrophoretic analysis of ribosomal and viral ribonucleic acids with a simple technique for slicing low-concentration polyacrylamide gels. | the electrophoretic mobilities of ribosomal ribonucleic acids (rna) from cultured mammalian (hela, vero, mdbk), avian (chick embryo), and bacterial (escherichia coli) cells, and rna species extracted from selected viruses (sindbis, polio, tobacco mosaic, sendai) were compared, employing a simple, inexpensive technique for slicing low-concentration polyacrylamide gels. the procedure provides for rapid fractionation of gels used for characterization of rna, incorporating extrusion and serial secti ... | 1971 | 4331767 |
| degradation of dna rna hybrids by ribonuclease h and dna polymerases of cellular and viral origin. | ribonuclease h from human kb cells, chick embryos, calf thymus, avian myeloblastosis virus, and rous associated virus specifically degrades the rna of dna.rna hybrids, producing mono- and oligoribonucleotides terminated in 5'-phosphates. the cellular rnase h is an endonuclease, whereas the viral enzyme appears to be an exonuclease. viral dna polymerase and rnase h copurify through all separation steps. therefore, rnase h activity is an intrinsic part of the viral dna polymerase. dna.rna hybrids ... | 1972 | 4343966 |
| invitro formation of assimilatory reduced nicotinamide adenine dinucleotide phosphate: nitrate reductase from a neurospora mutant and a component of molybdenum-enzymes. | an active neurospora-like assimilatory nadph-nitrate reductase (ec 1.6.6.2), which can be formed in vitro by incubation of extracts of nitrate-induced neurospora crassa mutant nit-1 with extracts of (a) certain other nonallelic nitrate reductase mutants, (b) uninduced wild type, or (c) xanthine oxidizing and liver aldehyde-oxidase systems was also formed by combination of the nit-1 extract with other acid-treated enzymes known to contain molybdenum. these molybdenum enzymes included (a) nitrogen ... | 1971 | 4399835 |
| anti-gamma globulins and chronic infection: comparative studies of the immune response to various bacteria and gamma globulin preparations. | a study of the relationship of clinical states associated with prolonged infection (bacterial endocarditis and osteomyelitis) and generation of serum anti-gamma globulins was made with particular reference to quantitative amounts of staphylococcal protein a in various infecting strains. no correlation between individual strain amounts of protein a and presence of anti-gamma globulins was detected. thirty-eight rabbits were immunized intravenously with various strains of bacteria (staphylococcus ... | 1972 | 4404684 |
| [practical experiences in the prevention and therapy of most important calf and young cattle diseases in large herds]. | | 1972 | 4569838 |
| transcription of brain chromatin by ribonucleic acid polymerases from brain nuclei and from escherichia coli. | 1. transcription of ox brain chromatin by brain nuclear rna polymerase ii and escherichia coli rna polymerase was studied. 2. the soluble chromatin prepared from brain nuclei contained dna, rna, histone and non-histone proteins. such chromatin preparations did not display any endogenous rna polymerase activity, when assayed in the presence of concentrations of kcl as high as 0.4m. 3. the chromatin-templated activity of brain nuclear polymerase ii was stimulated by kcl, with an optimum around 0.2 ... | 1972 | 4571299 |
| [studies, in the field, of a polyvalent vaccine against pulmonary infections in cattle]. | | 1972 | 4573942 |
| the kinetics of hydrolysis of synthetic glucuronic esters and glucuronic ethers by bovine liver and escherichia coli beta-glucuronidase. | 1. the relative rates of hydrolysis of synthetically prepared beta-d-glucuronic esters [aglycone: benzoic acid, veratroic (3,4-dimethoxybenzoic) acid, indol-3-ylacetic acid and ethylbutyric acid], and beta-d-glucuronic ethers (aglycone: phenolphthalein, p-nitrophenol, 3,4-dimethoxyphenol, 3,4-dimethoxybenzyl alcohol) by commercial preparations of beta-glucuronidase from bovine liver and escherichia coli were investigated. the rates of hydrolysis of all compounds tested were followed by measuring ... | 1973 | 4584027 |
| infection and immunoglobulin concentrations in chediak-higashi mice. | the chediak-higashi syndrome (chs) has been reported in man, cattle, mink, and mice. chs humans and cattle have an increased incidence of pyogenic infections, whereas chs mink are more susceptible to aleutian disease. age- and sex-matched groups of chs mice (mutant strain) and c57 bl/6n (parent strain) were challenged with candida albicans, escherichia coli, klebsiella pneumoniae, and staphylococcus aureus intravenously and streptococcus pneumoniae intraperitoneally. a significant increase (p < ... | 1974 | 4601767 |
| growth of indigenous organisms in aerated filtrate of feedlot waste. | filtrates from feedlot waste were incubated under aerobic conditions to evaluate the availability of nutrients for cell production and to assess the capacity of indigenous flora to produce stabilized effluents. incubation was carried out in 9-liter aerated jar fermentors. three-fourths of the organic material and one-third of the nitrogen were taken up in 4 days; 90% utilization of organic material and nitrogen required almost a month. acid was produced initially, but aerated liquid thereafter r ... | 1974 | 4609184 |
| continuous non-therapeutic use of antibacterial drugs in feed and drug resistance of the gram-negative enteric florae of food-producing animals. | fecal samples from illinois farm animals and montana range cattle were examined for the frequency of gram-negative enteric organisms resistant to oxytetracycline, dihydrostreptomycin, or ampicillin. the illinois farm animals were continually fed rations containing various antibacterial drugs. the montana range cattle had minimal exposure to antibacterial drugs. the majority of samples from illinois farm animals demonstrated 10% or more antibiotic-resistant organisms. in contrast, resistant organ ... | 1974 | 4615630 |
| phagocytosis of microbial l-forms. | little data are available regarding l-form phagocyte interactions. due to difficulty with more conventional methods, a serum-free technique of surface phagocytosis employing cellulose ester micropore filters, fluorochrome staining, and reflecting fluorescence microscopy was developed. intracellular localization of l-frms was confirmed by electron microscopy. in timed experiments, phagocytosis of a group d streptococcus (atcc 23241) and its l-form (t53i) were maximal at 30 min, although the bacte ... | 1972 | 4628960 |
| platelet interaction with bacteria. 3. ultrastructure. | the interaction of several common strains of bacteria with rabbit or human platelets in vitro has been examined sequentially with scanning and transmission electron microscopy. bacteria were added to platelets in their native plasma or to washed platelets in a balanced salt solution at ratios of about 1:1 or at low bacteria to platelet ratios (down to 1:100). the platelet-bacterial interaction (pbi) was studied with recording nephelometry. matched samples were fixed for microscopy at various poi ... | 1973 | 4632008 |
| evaluation of t3 coliphage injuries and efficacy of selected materials in preventing them. | a procedure was developed to analyze the inactivation of coliphage t3 during freeze-drying and subsequent rehydration. the amount of gross disruption of the phage as compared with the amount of phage remaining intact was evaluated by cesium chloride density gradient centrifugation. the amount of phage material able to adsorb to host cells and the residual infectivity after the drying were also evaluated. these analyses made it possible to determine the amount of phage material (i) degraded to pr ... | 1967 | 4860532 |
| volatile fatty acids and the inhibition of escherichia coli growth by rumen fluid. | concentrations of volatile fatty acids (vfa) normally found in bovine rumen fluid inhibited growth of escherichia coli in antibiotic medium 3. acetic, propionic, and butyric acids each produced growth inhibition which was markedly ph-dependent. little inhibition was observed at ph 7.0, and inhibition increased with decreasing ph. a combination of 60 mumoles of acetate, 20 mumoles of propionate, and 15 mumoles of butyrate per ml gave 96, 69, and 2% inhibition at ph 6.0, 6.5, and 7.0, respectively ... | 1969 | 4886864 |
| [detection of e. coli in cow's milk]. | | 1971 | 4942596 |
| characteristics of antimicrobial resistance of escherichia coli from animals: relationship to veterinary and management uses of antimicrobial agents. | five-hundred fifty-five (555) isolates of escherichia coli were obtained from fecal specimens of a representative number of animals from five farms in the united states. antibiotic exposure of the selected herds was determined by an epidemiological survey of these farms. the incidence of multiple resistance in the e. coli isolates was higher in herds exposed to continuous feeding of antimicrobial agents (84.8%) than in a herd not receiving antimicrobials (15.7%). the most common resistance confi ... | 1971 | 4943278 |
| [disinfection in colibacteriosis of small cattle]. | | 1971 | 4946542 |
| [microflora of the uterus in postpartum cows]. | | 1971 | 4946545 |
| uridinediphosphogalactose-4-epimerase deficiency in salmonella typhimurium and its correction by plasmoid-borne galactose genes of escherichia coli k-12: effects on mouse virulence, phagocytosis, and serum sensitivity. | the synthesis of smooth lipopolysaccharide (lps) in relation to mouse virulence and resistance to serum bactericidal activity in vitro and to rapid intravenous clearance in vivo was studied in salmonella typhimurium by using a virulent [median lethal dose (ld(50)) = 10(2)], smooth, and genetically marked strain, a uridinediphosphogalactose epimerase-deficient mutant of it which was, therefore, rough, and a derivative of the mutant made smooth again by acquisition of the galactose-positive genes ... | 1971 | 4949486 |
| in vitro and in vivo characterization of pyocin. | pyocin, a bacteriocin obtained from lysates of ultraviolet-induced cultures of pseudomonas aeruginosa was characterized in vitro and in vivo after 1,000-fold purification by chemical, column, and differential centrifugation procedures. electron micrographs of negatively stained pyocin preparations contained rod-shaped particles which resembled the contractile tail protein of the t-even phages of escherichia coli. although two separate and distinct pyocin fractions were eluted from diethylaminoet ... | 1967 | 4960899 |
| comparative studies of antigens from mycoplasma mycoides and escherichia coli. | extracts of sonically disrupted mycoplasma mycoides and escherichia coli were fractionated by sucrose density gradient centrifugation. the presence of antigen in each of the fractions was determined by complement-fixation and agar-gel diffusion precipitin tests, in which cow, pig, and rabbit anti-m. mycoides sera and rabbit anti-e. coli serum were used. fractions of m. mycoides, with a buoyant density of 1.225 or lower, fixed complement with cow and pig anti-m. mycoides sera. these fractions als ... | 1968 | 4967193 |
| antibacterial activity of dihydro-1,3-oxazine derivatives condensed with aromatic rings in positions 5,6. | 1. the antibacterial activity in vitro of dihydro-1,3-oxazine derivatives with aromatic rings condensed in positions 5, 6 was examined.2. of more than thirty compounds examined, two (t 615 and t 638) showed marked activity against various strains of mycobacterium tuberculosis at concentrations below 2 mug/ml.3. these two compounds also showed marked activity against escherichia coli, clostridium pneumoniae and salmonella typhi.4. both showed marked activity in vivo against tuberculosis produced ... | 1971 | 5003353 |
| [the properdin level in cattle during immunization and hyperimmunization with escherichia coli, pasteurella and tetanus toxin]. | | 1965 | 5321201 |
| prevalence of enteric pathogens in the feces of healthy beef calves. | fecal specimens from 136 healthy beef calves (1 day to 12 weeks of age) were examined for the presence of infectious agents known to cause enteric disease in calves. the calves were selected from 22 herds in which all calves were free of clinically apparent enteric disease. salmonella sp, enterotoxigenic escherichia coli, cryptosporidium, and coronavirus were not detected in any of the calves. three calves were infected with rotavirus and 1 calf was infected with yersinia enterocolitica. campylo ... | 1984 | 6089621 |
| homologous versus heterologous gene expression in the yeast, saccharomyces cerevisiae. | dna sequences normally flanking the highly expressed yeast 3-phosphoglycerate kinase (pgk) gene have been placed adjacent to heterologous mammalian genes on high copy number plasmid vectors and used for expression experiments in yeast. for many genes thus far expressed with this system, expression has been 15-50 times lower than the expression of the natural homologous pgk gene on the same plasmid. we have extensively investigated this dramatic difference and have found that in most cases it is ... | 1984 | 6096814 |
| mode of degradation of plasmid dna with ozone. | the ozonization of pbr322 closed circular dna showed the conversion to open circular dna. the damaged site was investigated by restriction mapping. the results showed the damage and subsequent cleavage of the dna strand of ccdna by ozonization may occur at the region sensitive to nuclease s1. | 1984 | 6097879 |
| [virological and bacteriological research on the etiology of gastroenteritis in newborn calves]. | virologic and bacteriologic studies were carried out of samples taken from calves with clinical gastroenteritis and from calves that died at the age of 2 to 10 days. a total of 199 samples were investigated of calves on 48 cattle-breeding farms. in 69 of the cases (34.2 per cent) strains of escherichia coli were isolated, prevailing being those of the o8, o9, o15, o21, o26, o55, and o78 serogroups. three of the strains isolated from fecal samples of clinically affected calves possessed the k99 a ... | 1984 | 6099625 |
| the early pathogenesis of bovine mastitis due to escherichia coli. | the pathogenesis of coliform mastitis was studied after infusing each of ten lactating quarters of three dairy cows with a large dose (ca. 1 x 10(9) colony-forming units) of virulent escherichia coli strain b117. this approach was adopted first to maximize the chance of observing microscopic lesions in the tissues of a gland and secondly to overwhelm the differences that might be shown between animals in their response to the infection. the infected glands were examined at intervals of up to 4 h ... | 1980 | 6109290 |
| new haemagglutinating fimbriae on escherichia coli strains isolated from urine. | the haemagglutination patterns of 255 urinary escherichia coli isolates were examined with human (a, rh+), bovine, chicken and guinea pig erythrocytes in the presence and absence of d-mannose. the strains were divided into four groups according to their haemagglutination properties. about 40% of the isolated agglutinated human red blood cells in the presence of d-mannose. the haemagglutinin of one of these. e. coli o18a, c: k- strain no. 119 was stable, temperature sensitive, did not develop at ... | 1980 | 6110318 |
| adhesion of enterotoxigenic escherichia coli in humans and animals. | enterotoxigenic escherichia coli (etec), an important cause of diarrhoea in humans and animal, require accessory virulence properties in addition to enterotoxin to manifest virulence. several classes of pili (hair-like protein surface organelles) promote adhesion of etec to small intestinal mucosa. antibody directed against adhesion pili interferes with colonization of the small intestine and prevents disease. this paper reviews studies with purified k88, k99 and 987 type pili used as parenteral ... | 1981 | 6114818 |
| antibody response of cows to escherichia coli pilus antigen k99 after oral vaccination with live or dead bacteria. | | 1983 | 6132572 |
| the production of f41 fimbriae by piglet strains of enterotoxigenic escherichia coli that lack k88, k99 and 987p fimbriae. | the enterotoxigenic escherichia coli strains 1676, 1706, 1751 and kec96a, which do not produce fimbrial adhesive antigens of the k88, k99 or 987p antigen type reacted both in vitro and in vivo with antiserum to f41 fimbriae in an indirect immunofluorescent antibody technique. antiserum used to demonstrate material b, an adhesive antigen thought to mediate the adhesive and mannose-resistant (mr) haemagglutinating properties of e. coli strains 1676, 1706 and 1751, reacted in vitro with an f41+ str ... | 1983 | 6138394 |
| the evolution of alpha-fetoprotein and albumin. i. a comparison of the primary amino acid sequences of mammalian alpha-fetoprotein and albumin. | the amino acid sequence of mouse alpha-fetoprotein has been deduced from the nucleotide sequence of its mrna and three chimeric plasmids containing overlapping segments of its cdna. a comparison of the amino acid sequence with that of either human and bovine albumin reveals in each case a 32% conservation of primary sequence. in addition, using the regularly spaced positions of cystine bridges, a 2-dimensional structure was generated, which revealed the presence of 3 closely related domains with ... | 1981 | 6161929 |
| immunological properties of escherichia coli heat-stable enterotoxins: development of a radioimmunoassay specific for heat-stable enterotoxins with suckling mouse activity. | antiserum was raised against the purified heat-stable enterotoxin (st) produced by enterotoxigenic escherichia coli strain 431, a class ii porcine enteropathogen. the antiserum was used to examine the antigenic determinants of sts produced by enterotoxigenic strains of different host origins and develop a sensitive radioimmunoassay specific for st having biological activity in suckling mice and piglets (sta). the antiserum neutralized one effective dose of toxin at a dilution of 1:5,000 and neut ... | 1981 | 6167519 |
| bactericidal activity of bovine serum against escherichia coli isolated from the environment in 3 herds of dairy cows. | | 1981 | 6179401 |
| identification of salmonellae of serogroup c1 by immunofluorescence and co-agglutination with antiserum against an oligosaccharide-protein conjugate. | antiserum specific for salmonella o7 antigen raised by immunisation of rabbits with an artificial conjugate consisting of oligosaccharide and bovine serum albumin (os-bsa). the oligosaccharide was a pentasaccharide isolated after cleavage of the o antigen polysaccharide chain of salmonella thompson (o antigen 6, 7) with endo-glycanase from bacteriophage 14. the usefulness of the s. thompson os-bsa antiserum for rapid and accurate identification of isolates of salmonella of serogroup c1 (o6, 7) w ... | 1982 | 6183432 |
| localization of the major antigenic determinant of edp208 pili at the n-terminus of the pilus protein. | trypsin digestion of pilin monomers from edp208 conjugative pili causes cleavage of lys12 to yield an n-terminal dodecapeptide, et1 (mr approximately equal to 1,500), and the remaining c-terminal fragment, er (mr approximately equal to 10,000). using the amino acid sequence for et1 provided by frost et al. (j. bacteriol. 153:950-954), we synthesized the n-terminal dodecapeptide chemically, conjugated it to bovine serum albumin, and subjected it to immunological studies. antisera prepared against ... | 1983 | 6185467 |
| a comparison of triclosan and chlorhexidine preparations with 60 per cent isopropyl alcohol for hygienic hand disinfection. | four detergent preparations containing triclosan; two alcoholic products, containing triclosan and chlorhexidine respectively, and a detergent preparation containing chlorhexidine were compared with 60 per cent isopropyl alcohol following a single hand wash using escherichia coli as the test organism. in vitro tests indicated that all had a high activity against hospital pathogens. the triclosan-containing preparations exhibited a significant pathogens. the triclosan-containing preparations exhi ... | 1983 | 6195237 |
| characterization of new hydrophobic pili of human enterotoxigenic escherichia coli: a possible new colonization factor. | enterotoxigenic escherichia coli strains were divided into five groups on the basis of their bacterial surface hydrophobicity (honda et al., fems microbiol. lett. 17:273-276, 1983). strains in group iii showed heat-stable high hydrophobicity, although they did not show mannose-resistant hemagglutination with either human or bovine erythrocytes. e. coli strain 260-1 in group iii was characterized. electron microscopic examination revealed the presence of pili on the surface of this strain, but no ... | 1984 | 6199307 |
| replication of m13mp7 single-stranded dna in vitro by the 9-s dna polymerase alpha from calf thymus. | the replication of m13 single-stranded dna by the 9s dna polymerase alpha from calf thymus has been studied in vitro. priming conditions, the nature of the replication products and conditions for optimal elongation have been investigated. oligonucleotides comprising only four nucleotides can serve as primers. both ribo and deoxy oligonucleotides can be elongated. priming by the short oligonucleotides occurs at multiple sites on the m13 genome. if replication is primed at single sites with a spec ... | 1984 | 6202519 |
| [primary and spatial structure of trna]. | the recent achievements in studying of structure of trna are considered in the present paper. a brief analysis of the new methods for sequencing trna was carried out. due to the development of these methods about 300 trna primary structures have been determined. comparison of the primary trna structures gives us the possibility to divide them into seven classes: prokaryotic initiator trnas and eukaryotic initiator trnas; prokaryotic elongator trnas and eukaryotic elongator trnas; archaebacterial ... | 1984 | 6209547 |
| nuclear genes coding the yeast mitochondrial adenosine triphosphatase complex. isolation of atp2 coding the f1-atpase beta subunit. | a yeast nuclear pet mutant of saccharomyces cerevisiae lacking any detectable mitochondrial f1-atpase activity was genetically complemented upon transformation with a pool of wild type genomic dna fragments carried in the yeast escherchia coli shuttle vector yep 13. plasmid-dependent complementation restored both growth of the pet mutant on a nonfermentable carbon source as well as functional mitochondrial atpase activity. characterization of the complementing plasmid by plasmid deletion analysi ... | 1983 | 6225776 |
| amino acid sequence of the oligomycin sensitivity-conferring protein (oscp) of beef-heart mitochondria and its homology with the delta-subunit of the f1-atpase of escherichia coli. | the complete amino acid sequence of the oligomycin sensitivity-conferring protein (oscp) of beef-heart mitochondria is reported. the protein contains 190 amino acids and has a molecular mass of 20 967. its structure is characterized by a concentration of charged amino acids in the two terminal segments (n 1-77 and c 128-190) of the protein, whereas its central region is more hydrophobic. the earlier reported homology of the protein with the delta-subunit of e. coli f1, based on the terminal amin ... | 1984 | 6229420 |
| stimulation of streptococcus thermophilus growth in mastitic milk. | growth of streptococcus thermophilus was faster in mastitic milk, aseptically collected following intramammary infusion of escherichia coli endotoxin, than in normal aseptically collected milk. the contribution of polymorphonuclear leucocytes (pmn), of plasma and plasmin to this stimulation has been investigated. addition of plasmin to low cell count milk stimulated growth of the streptococcus to the same degree as mastitic milk. however, addition of plasma or pmn from blood or from milk were le ... | 1984 | 6231318 |
| effect of serum albumin on siderophore-mediated utilization of transferrin iron. | the effect of serum and serum proteins on enterobactin- and aerobactin-mediated utilization of transferrin iron has been investigated. serum was found to impede transfer of iron from iron transferrin to enterobactin and from [55fe]ferric enterobactin to cells of escherichia coli bn3040 na 1r iuc . in contrast, serum had essentially no effect on the rate of these reactions mediated by aerobactin. three purified serum proteins, human serum albumin, bovine serum albumin, and human immunoglobulin, w ... | 1984 | 6234017 |
| isolation and properties of calmodulin from dictyostelium discoideum. | a calcium-dependent regulatory protein (calmodulin) was purified from vegetative amoebae of dictyostelium discoideum. the properties of dictyostelium calmodulin are similar but not identical to those of bovine brain calmodulin. calmodulin activity was not detected in extracts of saccharomyces cerevisiae or escherichia coli. | 1980 | 6243626 |
| dissociation and reconstitution of membranes synthesizing the peptidoglycan of escherichia coli. lipid dependence of the synthetic enzymes. | the peptidoglycan synthetic enzymes can be dissociated with cholate and licl into components with mobilities on a gel filtration column in the same ranges as bovine serum albumin. the active enzymes can be separated further from the lipids necessary for synthesis by precipitation with ammonium sulfate. the needed lipids stable to hydrolysis with base. a protein needed for peptidoglycan polymerization can be separated from the other synthetic enzymes by hydroxylapatite chromatography. | 1980 | 6244296 |
| the dna polymerase beta reaction with ultraviolet-irradiated dna incised by correndonuclease. | covalently closed circular col e1 dna was ultraviolet-irradiated with a dose of 60 j/m2, thus introducing about 3.2 pyrimidine dimers per dna molecule. treatment of irradiated col e1 dna with micrococcus luteus correndonuclease resulted, in the vicinity of pyrimidine dimers, in an average of 3.3 incisions per dna molecule, and converted dna to the open circular form. incised col e1 dna stimulated no reaction with calf thymus dna polymerase alpha but was recognized as a template by dna polymerase ... | 1980 | 6250619 |
| cloning of human papilloma virus genomic dnas and analysis of homologous polynucleotide sequences. | the complete dna genomes of four distinct human papilloma viruses (human papilloma virus subtype 1a [hpv-1a], hpv-1b, hpv-2a, and hpv-4) were molecularly cloned in escherichia coli, using the certified plasmid vector pbr322. the restriction endonuclease patterns of the cloned hpv-1a and hpv-1b dnas were similar to those already published for uncloned dnas. physical maps were constructed for hpv-2a dna and hpv-4 dna, since these viral dnas had not been previously mapped. by using the cloned dnas, ... | 1980 | 6253665 |