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J M Merrick

Publications and source records attributed to J M Merrick.

35 records · Page 2Linked to original sources
PubMed1981

Studies on Paul-Bunnel (P-B) antigen-antibody system. I. Two distinct P-B antigens.

The multiple nature of heterophile, Paul-Bunnel (P-B) antigen has been suggested by our previous studies as well as those of others. In the present study, two distinct antigens of P-B specificity were defined by means of hemagglutination and immunodiffusion tests in agarose gel; one antigen (BS) was shared by bovine (BRBC) and sheep red blood cells (SRBC) and another antigen (B) was limited to BRBC. Both anti-BS and anti-B antibodies were shown to be present in sera of 106 patients with infectious mono-nucleosis (IM) whereas they were virtually absent from the sera of the vast majority of patients with diseases other than IM and normal sera. Absorption and agglutination inhibition tests demonstrated the presence of BS and B antigens on horse erythrocytes. Goat erythrocytes were also shown to possess BS antigen, however, B antigen was found on erythrocytes of some but not all individual goats. By means of the previously established procedure, BS antigen was extracted from stromata of BRBC, SRBC and erythrocytes of horse and goat, and B antigen from BRBC and erythrocytes of some goats. BS and B antigens were also extracted from bovine lymphocytes and murine thymus and spleen tissues but not murine erythrocytes.

Absorption↗
PubMed1981

Studies on Paul-Bunnell (P-B) antigen-antibody system. II. P-B antigens in extracts of lymphoma-leukemia spleens and pathologic sera.

Preparations obtained by the chloroform-methanol extraction procedure from spleen tissues of patients with Hodgkin's disease, lymphomas, and leukemias, as well as from peripheral blood buffy coat of infectious mononucleosis (IM) patients were studied for the presence of 2 Paul-Bunnell (P-B) antigens; BS antigen shared by bovine red blood cells (BRBC) and sheep red blood cells (SRBC) and another, B antigen characteristic for BRBC. Both BS and B antigens were demonstrated by means of agglutination inhibition tests in over 40% of these extracts. None of the extracts from spleens, tonsils, and buffy coat of apparently normal human beings contained these antigens. P-B antigens of lymphoma-leukemia extracts were further purified by DEAE-Sephadex column chromatography. The purified fractions of some of these spleen extracts formed a precipitation line with IM sera, which merged into a reaction of identity with the lines formed by P-B antigens of BRBC. In studying various pathologic sera, B antigen was detected in sera of 28% of lymphoma-leukemia patients, 15% of patients with carcinomas of internal organs, and 3% of patients with systemic lupus erythematosus. On the other hand, BS antigen was found in only 3% of lymphoma-leukemia sera. These results confirmed our previous observations and indicated that both BS and B antigens are expressed as neoantigens on the patient's spleen cells as a result of pathologic processes in lymphoreticular malignancies.

Agglutination Tests↗
PubMed1979

Alterations in glycosphingolipid patterns in a line of African green monkey kidney cells infected with herpesvirus.

The major glycosphingolipids (GSLs) of a line of African green monkey kidney cells (BGM) were characterized as glucosylceramide, lactosylceramide, galactosyl-galactosyl-glucosylceramide, and N-acetylgalactosaminyl-galactosyl-galactosyl-glucosylceramide. Neutral GSLs accounted for approximately 80% of the total GSLs isolated. The predominant gangliosides were N-acetylneuraminyl-galactosyl-glucosylceramide, N-acetylgalactosaminyl-N-acetylneuraminyl-galactosyl- glucosylceramide, and galactosyl-N-acetylgalactosaminyl-N-acetylneuraminyl -galactosyl-glucosylceramide. The incorporation of labeled galactose into GSLs was compared in mock-infected and herpes simplex virus type 1-infected BGM cells. Herpes simplex virus type 1 infection resulted in a three- to four-fold increase in galactose incorporation into glucosylceramide and a decrease in galactose incorporation into galactosyl-galactosyl-glucosylceramide and N-acetyl-galactosaminyl-galactosyl-galactosyl-glucosylceramide. The virus-induced alteration in the GSL labeling pattern occurred early in infection, before the release of infectious virus, and was not prevented by the presence of cytosine arabinoside. Treatment of uninfected BGM cells with cycloheximide resulted in alterations in the GSL pattern which were similar to those observed in herpes simplex virus type 1-infected cells. These observations suggest that an early virus function such as inhibition of host cell protein synthesis is responsible for the observed alterations of GSL metabolism. Experiments with a syncytium-producing strain of herpes simplex virus type 1, herpes simplex virus type 2, and pseudorabies virus indicated that other herpes viruses altered GSL metabolism in a manner similar to herpes simplex virus type 1.

Animals↗
PubMed1978

Characterization of the Hanganutziu-Deicher (serum-sickness) antigen as gangliosides containing n-glycolylneuraminic acid.

Gangliosides that possess the same sugar sequence but differing in the type of sialic acid (N-acetyl- or N-glycolylneuraminic acid) were compared for their reactivity with Hanganutziu-Deicher ('serum sickness') antibodies by double-diffusion gel precipitation tests. Only N-glycolylneuraminic acid containing gangliosides formed precipitation lines with Hanganutziu-Deicher antibodies, thus suggesting that Hanganutziu-Deicher antigens are gangliosides that contain N-glycolylneuraminic acid.

Antibody Specificity↗
PubMed1977

Isolation and partial characterization of the heterophile antigen of infectious mononucleosis from bovine erythrocytes.

The heterophile antigen (Paul-Bunnell antigen, PBA) of infectious mononucleosis was isolated by extraction of an aqueous suspension of bovine erythrocyte stromata with chloroform-methanol (2:1). The upper aqueous layer contained gangliosides, PBA, and a high-molecular-weight glycoprotein. PBA and gangliosides were separated from the high-molecular-weight glycoprotein by extraction of lyophilized upper layer with chloroform-methanol solvents. Separation of PBA from gangliosides was carried out by chromatography on DEAE-cellulose with chloroform-methanol solvents. PBA appeared to be a minor glycoprotein component of the erythrocyte membrane and had both hydrophobic and hydrophilic properties. It was soluble in either organic or aqueous solvents. On SDS-polyacrylamide gel electrophoresis, it migrated as a single component that stained for protein with Coomassie blue, for carbohydrate with periodic acid-Schiff reagent, and for lipid with oil red 0; it had an apparent molecular weight of 26,000. It was composed of 62% protein with major amino acids; glutamic acid, proline, glycine, isoleucine, leucine, and threonine (158, 116, 98, 90, 85, and 82 residues per 1,000 residues, respectively). Carbohydrate content was 9.2% with major sugar constituents: sialic acid, galactosamine, and galactose. Serologic activity of PBA was destroyed by pronase but not by trypsin.

Amino Acids↗
PubMed1977

Purification and properties of the periplasmic glucose-binding protein of Pseudomonas aeruginosa.

A glucose-binding glycoprotein (GBP) from the periplasm of Pseudomonas aeruginosa was purified to homogeneity as judged by polyacrylamide gel electrophoresis, molecular sieve chromatography, and double-diffusion gel precipitation. It had an average molecular weight of 44,500 and an isoelectric point of 4.7. One mole of glucose was bound per mole of GBP with a dissociation constant of 0.35 muM. The binding of radioactive glucose by GBP was not significantly inhibited by 10-fold-higher concentrations of other carbohydrates; however, a number of related compounds were found to compete at 100-fold-higher concentrations. Amino acid analyses revealed predominant amounts of alanine, glutamate, and glycine and a low content of sulfur-containing amino acids. The carbohydrate moiety of GBP, comprising nearly 16% of the total weight, contained galactosamine, glucosamine, fucose, galactose, glucose, and mannose. A GBP-deficient mutant, strain MB723, was found to be defective in both membrane transport and glucose chemotaxis. Strain MB724, a revertant to GBP-positive phenotype, simultaneously recovered normal levels of both membrane functions.

Bacterial Proteins↗
PubMed1976

Isolation of dicarboxylic acid- and glucose-binding proteins from Pseudomonas aeruginosa.

Inducible binding proteins for C4-dicarboxylic acids (DBP) and glucose (GBP) were isolated from Pseudomonas aeruginosa by extraction of exponential-phase cells with 0.2 M MgC12 (pH 8.5) and by an osmotic shock procedure without affecting cell viability. DBP synthesis was induced by growth on aspartate, alpha-ketoglutarate, succinate, fumarate, malate, and malonate but not by growth on acetate, citrate, pyruvate, or glucose. Binding of succinate by DBP was competitively inhibited by 10-fold concentrations of fumarate and malate but not by a variety of related substances. GBP synthesis and transport of methyl alpha-glucoside by whole cells were induced by growth on glucose or pyruvate plus galactose, 2-deoxyglucose, or methyl alpha-glucoside but not by growth on gluconate, succinate, acetate, or pyruvate. The binding of radioactive glucose by GBP was significantly inhibited by 10-fold concentrations of glucose, galactose, and glucose-1-phosphate but not by the other carbohydrates tested. The binding of glucose by GBP or succinate by DBP did not result in any chemical alteration of the substrates.

Bacterial Proteins↗
PubMed1974

Extracellular enzyme secretion by Pseudomonas lemoignei.

The ability of succinate to repress the secretion of Pseudomonas lemoignei poly-beta-hydroxybutyrate depolymerase was a function of pH. Repression only occurred when the pH of the medium was 7.0 or less. At a higher pH, lack of sensitivity to succinate concentration may have been due to a limited ability to transport succinate. Actively secreting cultures (at pH 7.4) continued to secrete enzyme for approximately 30 min after the pH was rapidly decreased to pH 6.8, even though sufficient succinate was present to repress enzyme synthesis. Similarly, after the addition of rifampin to secreting cultures, there was a 30-min delay before secretion was inhibited. Evidence is presented which suggests that continued secretion may be the result of depolymerase messenger ribonucleic acid accumulation within the cells. Studies with chloramphenicol indicated that de novo protein synthesis is necessary for the secretion of poly-beta-hydroxybutyrate depolymerase and that exoenzyme is not released from a preformed pool. Studies with various inhibitors of protein synthesis indicated that synthesis of exoenzyme is 5 to 10 times more susceptible to inhibition than is the synthesis of cell-associated proteins.

Bacterial Proteins↗
PubMed1971

Metabolism of poly- -hydroxybutyrate: effect of mild alkaline extraction on native poly- -hydroxybutyrate granules.

Mild alkaline extraction of native poly-beta-hydroxybutyrate (PHB) granules results in the solubilization of a protein fraction. Both the solubilized protein fraction and the extracted granules are essentially devoid of PHB synthetase activity unless recombined. The protein fraction has been separated by chromatography into two components (A-I and A-II). A-I but not A-II can be recombined with extracted granules to give rise to PHB synthetase activity. Extracted granules no longer require pretreatment with activator or trypsin but are directly susceptible to hydrolysis by Rhodospirillum rubrum depolymerase. Addition of A-II or A-I prevents the direct hydrolysis by depolymerase. The inhibition is reversed by activator or trypsin. We conclude that native granules are associated with a protein inhibitor which prevents the hydrolysis of PHB by depolymerase unless the protein is destroyed by trypsin, removed by alkaline extraction, or modified by activator.

Bacillus megaterium↗
PubMed1968

Identification of propionate as an endogenous CO2 acceptor in Rhodospirillum rubrum and properties of purified propionyl-coenzyme A carboxylase.

A heat-stable endogenous CO(2) acceptor has been found in extracts of Rhodospirillum rubrum grown photoheterotrophically on acetate. Evidence is presented which suggests that this factor is propionic acid. Thus, paper and gas chromatographic analyses have indicated that propionic acid is present in boiled extracts prepared from R. rubrum cells. The products of (14)CO(2) fixation obtained with either the boiled extract or propionic acid as the CO(2) acceptor were identical and were identified as methylmalonic acid and succinic acid by paper chromatography. The enzyme which catalyzes the carboxylation of propionyl-coenzyme A (propionyl-CoA carboxylase) was purified from R. rubrum cells grown on acetate and its properties were studied. The enzyme is similar to propionyl-CoA carboxylases isolated from mammalian sources.

Butyrates↗
PubMed1965

Effect of polymyxin B, tyrocidine, gramicidin D, and other antibiotics on the enzymatic hydrolysis of poly-beta-hydroxybutyrate.

Merrick, J. M. (State University of New York, Buffalo). Effect of polymyxin B, tyrocydine, gramicidin D, and other antibiotics on the enzymatic hydrolysis of poly-beta-hydroxybutyrate. J. Bacteriol. 90:965-969. 1965.-Previous studies have demonstrated that native poly-beta-hydroxybutyrate (PHB) granules isolated from Bacillus megaterium are surrounded by a discrete membranelike structure. Morphological alterations of PHB granules are mainly characterized by membrane fragmentation, and can be correlated with decreased susceptibility of the polymer to enzymatic hydrolysis by soluble factors. In the present investigation, the inhibitory effect of a variety of surface-active and other antibiotics on the enzymatic depolymerization of PHB was examined. The most potent inhibitors were polymyxin B, tyrocidine, and gramicidin D. These polypeptide antibiotics are known to attack other types of membranous structures. The results, therefore, support previous evidence that the membrane or similar constituents of PHB granules are intimately involved in its metabolism. Chlortetracycline was also found to be a potent inhibitor of the depolymerization, but its mechanism of action may be different from the other antibiotics. The polymer-synthesizing enzyme(s), also localized on the granules, is inhibited by tyrocidine and gramicidin D but not by polymyxin B or chlortetracycline.

Antimycin A↗
PubMedDate not supplied

Hydrolysis of native poly(hydroxybutyrate) granules (PHB), crystalline PHB, and artificial amorphous PHB granules by intracellular and extracellular depolymerases.

Native poly(hydroxybutyrate) (PHB) granules, purified PHB and artificial amorphous PHB granules were examined as putative substrates for hydrolysis by the intracellular depolymerase system of Rhodospirillum rubrum and the extracellular depolymerase of Pseudomonas lemoignei. The R. rubrum depolymerizing system requires pretreatment of granules with a heat stable 'activator' fraction; the activator can be replaced by mild trypsin treatment. Artificial granules were prepared with a cationic detergent, cetyltrimethylammonium bromide (CTAB) and an anionic detergent, (sodium cholate). Cholate and CTAB PHB granules were hydrolyzed by both enzyme systems; however, some differences were noted. Cholate granules were hydrolyzed in the absence of the R. rubrum activator fraction. Activator was required for the hydrolysis of CTAB granules but could be replaced by heparin in the extracellular depolymerase system but not in the intracellular depolymerase system. A Triton X-114 extract of native PHB granules inhibited the hydrolysis of trypsin-activated granules by the intracellular depolymerase. The inhibition was reversed by the activator fraction. Detergent extracts of granules activated with the R. rubrum activator were unable to inhibit the hydrolysis of trypsin-activated granules. These data suggest that the activator acts to modify an inhibitor present on native granules.

Bacillus megaterium↗
PubMedDate not supplied

Immunization of the gastrointestinal tract with bacterial and viral antigens: implications in mucosal immunity.

The effects of oral immunization with Pseudomonas aeruginosa (PAOI), Chlamydia trachomatis or respiratory syncytial virus (RSV) on the development of specific antibody responses in the intestine, respiratory tract and genital secretions was studied in several animal models. Oral immunization resulted in the development of specific immunity in distant mucosal sites. However, its role in influencing the outcome of reinfection challenge at the distant site varied with the antigen. Little or no protection was observed against infection with Pseudomonas aeruginosa in the respiratory tract. Limited protection was observed against respiratory tract infection with RSV. On the other hand oral immunization appeared to be quite effective in preventing respiratory or genital infection with Chlamydia trachomatis. Finally, preliminary studies have suggested that intestinal immunization via the process of breast feeding can also be employed as an effective means to induce anti-idiotypic immunity against RSV in the breast feeding neonates.

Animals↗