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H D Slade

Publications and source records attributed to H D Slade.

At least 19 recordsLinked to original sources
PubMed1979

Serotype-dependent inhibition of glucan synthesis and cell adherence of Streptococcus mutans by antibody against glucosyltransferase of serotype e S. mutans.

A crude glucosyltransferase (GTase) preparation was obtained from the culture supernatant of Streptococcus mutans strain MT703 (serotype e) by 50% ammonium sulphate precipitation. Antiserum specific against the GTase was prepared by immunizing rabbits intramuscularly with the GTase in Freund incomplete adjuvant, followed by GTase without adjuvant intravenously. Gamma globulin fractions of the antiserum and normal serum were partially purified by 1/3 saturated ammonium sulphate precipitation. The antibody strongly inhibited the GTase activity (greater than 90%) of type c, e and f S. mutans, whereas the GTase of type a, d and g was not affected by the antibody. The GTase from type b S. mutans was slightly inhibited. The adherence of viable cells of type c, e, and f S. mutans to a glass surface due to synthesis of glucan by the cell-associated GTase was also significantly inhibited by the antibody to the enzyme. These results suggest that type c, e, and f and types a, d, and g S. mutans can be separated into two major groups in terms of the immunological relationship of GTase.

Antibodies, Bacterial↗
PubMed1979

Properties of Streptococcus mutans grown in a synthetic medium: binding of glucosyltransferase and in vitro adherence, and binding of dextran/glucan and glycoprotein and agglutination.

The influence of culture media on various properties of Streptococcus mutans was investigated. Strains of S. mutans (serotypes c, d, f, and g) were grown in a complex medium (Todd-Hewitt broth [THB]) or a synthetic medium (SYN). The SYN cells, in contrast to THB cells, did not bind extracellular glucosyltransferase and did not produce in vitro adherence. Both types of cells possessed constitutive levels of glucosyltransferase. B13 cells grown in SYN plus invertase-treated glucose possessed the same level of constitutive enzyme as THB cells. In contrast to THB cells, the SYN cells of seven serotype strains did not agglutinate upon the addition of high-molecular-weight dextran/glucan. Significant quantities of lower-molecular-weight (2 x 10(4) or 7 x 10(4)) dextran and B13 glucan were bound by SYN cells. SYN cells agglutinated weakly in anti-glucan serum (titers, 0 to 16), whereas THB cells possessed titers of 32 to 256. Evidence for the existence of a second binding site in agglutination which does not possess a glucan-like polymer has been obtained. B13 cells grown in invertase-treated THB agglutinated to the same degree as normal THB cells. The nature of this site is unknown. SYN cells possess the type-specific polysaccharide antigen. B13 cells did not bind from THB a glycoprotein which reacts with antisera to the A, B, or T blood group antigens or which allows agglutination upon the addition of dextran. The results demonstrate that S. mutans grown in a chemically defined medium possesse markedly different biochemical and biological activities than cells grown in a complex organic medium.

Agglutinins↗
PubMed1978

Dextran/glucan binding by Streptococcus mutans: the role of molecular size and binding site in agglutination.

1) S. mutans strains of serotypes a, d and g were strongly agglutinated with soluble glucans and dextran T2000. Homologous glucan did not in all cases produce agglutination. 2) The quantity of low molecular weight dextrans bound (T20 and T70) does not correspond to the agglutination induced by glucan or T2000. 3) The agglutination and binding of high molecular weight glucan by B13 cells was sensitive to heat, trypsin, dextranase, EDTA, SDS and urea, whereas no inhibition of binding of T20 and T70 was seen. 4) Pretreatment of B13 cells with anti-d, or anti-glucan sera, or Con A, RCA I, or RCA II completely inhibited agglutination by T2000 and caused a significant reduction of the binding of glucan. No reduction in the binding of T20 and T70 occurred. 5) An agglutination-negative mutant was agglutinated by sucrose but not by T2000 or high molecular weight glucan. It bound normal levels of T20 and T70. 6) The results indicate that B13 cells possess multiple glucan binding sites and that the site responsible for agglutination consists of both polysaccharide and protein. 7) Inhibition studies on agglutination and adherence using B13 cells indicate that the two processes involve different mechanisms.

Antibodies, Bacterial↗
PubMed1978

Isolation and characterization of a Streptococcus mutans bacteriocin inhibitor from Streptococcus pyogenes.

An inhibitor of Streptococcus mutans strain GS5 bacteriocin was released from a bacteriocin-sensitive strain of S. pyogenes by sonic treatment and partly purified by gel filtration on a Sepharose 6B column. The inhibitory factor was sensitive to heat, trypsin, and periodate and possessed a molecular weight of approximately 93,000. This factor may be the receptor for the S. mutans bacteriocin.

Bacterial Proteins↗
PubMed1978

Binding of glucosyltransferase and glucan synthesis by Streptococcus mutans and other bacteria.

Lyophilized and heat-treated cells from the seven serotypes of Streptococcus mutans were examined for their ability to bind added insoluble-product glucosyl-transferase (GTase) and to synthesize cell-associated glucan from [(14)C]sucrose. Lyophilized cells of serotypes a and g did not synthesize any more additional glucan than did the controls after exposure to GTase. These cells, however, synthesized four- to eightfold-greater quantities of glucan than did the cells of the remaining serotypes. Lyophilized cells of serotypes b, c, d, e, and f synthesized two- to threefold-greater quantities of glucan after exposure to GTase than did the controls without added enzyme. Lyophilized cells of serotypes a and g synthesized 6- to 10-fold-greater quantities of glucan than did heat-treated cells of the same strain after binding of GTase. Lyophilized cells of the remaining serotypes synthesized only 1.6- to 3.3-fold-greater quantities of glucan than did the heat-treated cells. These results demonstrate that heat treatment to inactivate cell-associated GTase does not create additional GTase binding sites in S. mutans and that serotypes a and g are considerably more active in cell-associated glucan synthesis than cells of the other five serotypes. Ten species of gram-positive and gram-negative bacteria from five genera which do not produce in vitro plaque synthesized 10- to 100-fold-less glucan than did the S. mutans strains after exposure to GTase. Of these species, S. sanguis, Actinomyces viscosus, and A. naeslundii synthesized the largest quantities of glucan. Three mutant strains of S. mutans which possess a reduced ability for in vitro adherence but do agglutinate with glucan or dextran synthesized only one-third as much glucan after binding of GTase as the control. These results are discussed in relation to in vitro and in vivo plaque development and the agglutination of S. mutans. The results support earlier findings which indicate that the presence of bacterial species other than S. mutans in smooth-surface dental plaque is due in part to contact of the cells with glucan in the developing plaque and not to the binding of cell-free GTase and the in situ synthesis of glucan. The results obtained with these representative strains of the seven serotypes of S. mutans may not apply to the same extent to other strains within the serotypes.

Escherichia coli↗
PubMed1977

Binding of lectins to Streptococcus mutans cells and type-specific polysaccharides, and effect on adherence.

The lectin concanavalin A (Con A) agglutinated the cells of 13 of 15 strains of the seven serotypes of Streptococcus mutans in an 18-h incubation period. Strains of types a, d, f, and g agglutinated within 2 h. Strains of a, d, and f were also agglutinated in 2 h by the castor bean lectin RCA. S. sanguis, S. salivarius, S. bovis, Actinomyces viscosus, A. naeslundii, and Lactobacillus plantarum were agglutinated within 2 h. The S. mutans type f polysaccharide was precipitated by Con A. The a, b, c, d, and e polysaccharides were not precipitated. Glucan from d and e strains of S. mutans and dextran T2000 were also precipitated by Con A. D-glucose inhibited the agglutination of type f cells by Con A and the agglutination of type d cells by D-galactose. The quantity of [acetyl-3H]Con A bound was not proportional to the degree of agglutination. Cells grown in sucrose medium bound more Con A than those grown in glucose medium. After treatment with dextranase, the sucrose-grown cells bound two- to fourfold more Con A. The binding of Con A to the type-specific polysaccharide or to teichoic acid could not be determined by the use of specific antibody due to the binding of Con A to the antibody globulin on the cell surface. Con A bound to S. mutans cells did not inhibit the activity of cell-bound glucosyltransferase, glucan synthesis, and in vitro adherence. Bound Con A also did not inhibit the ability of heat-treated cells to bind glucosyltransferase, synthesize glucan, and produce in vitro adherence.

Agglutination↗
PubMed1976

Characterization of an anti-glucosyltransferase serum specific for insoluble glucan synthesis by Streptococcus mutans.

An anti-glucosyltransferase serum, which synthesized 96% insoluble glucans, was prepared against a purified enzyme preparation from Streptococcus mutans strain HS6 (serotype a). This serum was examined for its effects on glucan synthesis by crude enzyme preparations from eight strains (four serotypes) of S. mutans and for the ability of these preparations to promote adherence of S. mutans to a smooth surface. Glucosyltransferase activity was assayed by measuring the incorporation of glucose from [14C]glucose-labeled sucrose into water-insoluble and water-soluble (ethanol-insoluble) glucans. Anti-glucosyltransferase serum inhibited insoluble glucan synthesis by crude enzyme preparations from cells of the four serotypes of S. mutans. Enzymes from strains of types a, b, and d were inhibited between 70 to 90%; enzymes from type c strains were inhibited from 45 to 60%. The adherence to a glass surface of heat-killed cells from these four serotypes was likewise inhibited. Soluble glucan synthesis was not inhibited by the serum, and in some cases its synthesis increased as insoluble glucan synthesis decreased.

Cell Adhesion↗
PubMed1976

Chemical and immunological properties of the type f polysaccharide antigen of Streptococcus mutans.

The type-specific cell wall polysaccharide antigen was extracted, purified, and characterized from type f Streptococcus mutans strain OMZ175 and MT557. The antigen was extracted from lyophilized cells with 5% trichloroacetic acid at 85 C for 15 min or saline at 120 C for 30 min. The trichloroacetic acid antigen was chromatographically separated into three antigenic fractions on a diethylaminoethyl-Sephadex A-25 column. Antigen 1 (Ag1P), which was specific for type f antiserum, was further purified by passing through carboxymethyl-Sephadex C-25 and Sephadex G-200 columns. It was a polysaccharide composed of 49% rhamnose and 47% glucose. No reaction was obtained with anti-polyglycerophosphate (PGP) serum. Antigen 2 was reactive with both type f and PGP antisera and contained significant amounts of protein and phosphorus. Antigen 3 was reactive only with PGP antiserum and had no type specificity. The polysaccharide antigen gave a single precipitin band against type-specific antiserum on immunodiffusion and immunoelectrophoresis. The presence of alpha-1,6-glucosidic linkages was indicated by a 90% inhibition of the precipitin reaction by isomaltose and alpha-methyl-D-glucopyranoside, adsorption to and release from a concanavalin A-Sepharose column, and reaction with an S. mutans (type e) glucan antiserum. This antiserum was used to show that the type f polysaccharide antigen did not contain free glucan. An analysis of the antigen released from the antigen-glucan antiserum complex showed the presence of rhamnose and glucose. This released antigen also reacted with an f antiserum, which did not react with commercial dextran. The results show that the type f polysaccharide antigen is the first of those S. mutans type-specific polysaccharides identified to be immunologically related to an S. mutans glucan.

Antigens, Bacterial↗
PubMed1976

Purification and immunochemical characterization of type e polysaccharide antigen of Streptococcus mutans.

The type-specific antigen of Streptococcus mutans strain MT703, serotype e, has been chromatographically purified and characterized. Two chromatographic fractions were obtained from saline extracts which reacted with both anti-MT703 whole-cell serum and Lancefield group E serum. The major fraction (eI) was identified as a polysaccharide composed of 37% glucose, 56% rhamnose, 5% protein, and 0.3% phosphorus, whereas the minor fraction (eII) contained 66% protein in addition to 10% glucose and 17% rhamnose. The immunological specificity of these antigens was found to be the same by immunodiffusion in agar gel. Another fraction with a negative charge (eIII) reacted with polyglycerophosphate antisera from Streptococcus mutans and Streptococcus pyogenes. For comparison, the MT703 antigen in a hot trichloroacetic acid extract (eA) and the group E antigen from a saline extract of cells of strain K129 (EI) were similarly purified by anionic ion-exchange chromatography. Although the ratio of glucose and rhamnose in eA was 1:0.9 and in eI and eII approximately 1:1.5, reactions of identity were obtained in gel diffusion against specific anti-e serum. This difference in ratio is probably a result of the extraction procedures. Both the type e and group E antisera were reactive with both eI and EI antigens. The adsorption of group E antiserum with MT703 cells removed all E antibody, whereas type e-specific antibody remained after adsorption with K129 cells. These results suggest that eI antigen possesses both e and E specificities, whereas EI possesses E only. These findings were supported by the quantitative precipitin test and immunodiffusion and/or immunoelectrophoretic patterns in agar gel. Methyl-beta-D-glucopyranoside markedly inhibited the precipitin reaction in both type e and group E sera. However, a significantly stronger inhibition by cellobiose of type e serum than of group E serum indicates that a beta-linked glucose-glucose dimer is the predominant antigenic determinant of the e specificity. The presence of both e and E specificities on a single polysaccharide molecule was demonstrated by the use of purified e antigen released from a specific e-anti-e complex. This antigen reacted with a group E-specific serum as well as a type e-specific serum. An examination of five S. mutans type e strains showed the presence of group E specificity also, whereas the I, II, and IV serotypes of group E streptococci only possessed the group E specificity.

Antigens, Bacterial↗
PubMed1976

Selective adsorption of heterophile polyglycerophosphate antigen from antigen extracts of Streptococcus mutans and other gram-positive bacteria.

Hot saline extracts of Streptococcus mutans have been shown to contain antigenic substances which occasionally react nonspecifically with some antisera against whole cells of various serological groups and types of streptococci. Chromatography of the extract of S. mutans strain MT703 (serotype e) on a diethylaminoethyl-Sephadex A-25 column gave two principal antigens. One antigen was eluted without adsorption to the resin and was identified as the serotype-specific polysaccharide. The other antigen, which contained a large quantity of phosphorus, was absorbed to and released from the resin by gradient elution. It was reactive against the antisera specific for polyglycerophosphate (PGP) from group A Streptococcus pyogenes and/or S. mutans strain Ingbritt (type c). The PGP antigen was further purified by gel filtration with Sephadex G-75. Two peaks, PGP-1, and PGP-2, were obtained. Each possessed the same antigenic specificity to anti-PGP serum as shown by immunodiffusion. Chemical analyses revealed that the molar ratio of phosphorus to glycerol in both was about 1:1, although the protein content between the two was significantly different. PGP antigen was found to be widely distributed in hot saline extracts from various gram-positive bacteria, with a few exceptions. However, all gram-negative bacteria examined were free of PGP. The PGP in the hot saline extracts of various gram-positive bacteria possessed an essentially identical antigenic specificity. The addition of diethylaminoethyl-Sephadex A-25 resin to hot saline extracts successfully removed the cross-reacting PGP antigen. After adsorption of the extract from S. mutans, the supernatant contained only type-specific polysaccharide antigen, except type b, in which both type b-specific polysaccharide and PGP antigens were absorbed with the resin. This simple procedure should be useful for the removal of the PGP-type teichoic acid from antigen extracts of bacteria that contain uncharged polysaccharides.

Antigens, Bacterial↗
PubMed1976

Chemical composition of Streptococcus mutans type c antigen: comparison to type a, b, and d antigens.

Studies of the serotype a, b, and d antigens of S mutans were extended to include the serotype c antigen. Type c antigen was extracted from cells of strain Ingbritt and purified by repeated column chromatography. Two type c antigens fractions were separated by chromatography on DEAE-Sephadex and were designated I and II. On agar gel diffusion, the major components of antigens I and II were serologically identical with the major component of the crude Ingbritt extract. Rhamnose and glucose were present in a 2.4:1 ratio and comprised 98 and 93% of the purified antigens, respectively. The compositions of the c antigens were directly related to the carbohydrate content of the serotype c cell wall. In contrast, purified a, b-II, and d antigens, which are also cell wall polysaccharides contain only trace amounts of rhamnose, a major wall carbohydrate. Studies which used comparative immunoelectrophoresis demonstrated that the purified a, b-I, and d antigens were serologically identical to the antigen preparations that have been used for the immunological classification of these serotypes.

Antigens, Bacterial↗
PubMed1976

Adherence of serotype e Streptococcus mutans and the inhibitory effect of Lancefield group E and S mutans type e antiserum.

S mutans strain MT703 from an active carious lesion in the tooth of a child had type e specificity and showed a cross-reaction with the Lancefield group E cell wall streptococcal polysaccharide antigen. Heat-killed cells MT703 adhered to a glass surface in the presence of CGT MT703 and sucrose. Pretreatment of the cells with anti-MT703 whole cell serums inhibited adherecne. The removal of glycerol teichoic acid antibody and group E antibody from the MT703 serum did not result in a loss of inhibitory activity. Antiserum with or without adsorption significantly inhibited glucan synthesis by CGT from sucrose. Antibodies specific for the polyglycerol phosphate of teichoic acid did not inhibit adherence. Anti-group E serum and serums specific for other types of S mutans, did not show adherence inhibitory activity except for an occasional type c specific antiserum. Antibody specific for the type e antigen produced significant inhibition of the binding of CGT to the MT703 cell wall, and adherence of these cells did not occur. Antibody to CGT inhibited glucan synthesis. Treatment of the cells with dextranase, dextran antibody, or trypsin caused a significant reduction in adherence. The results suggest that the type antigen and dextran on the surface of the S mutans type e cell are functional in adherence, and that these polymers are associated with cell wall protein.

Glucose↗
PubMed1975

Serological purification of polysaccharide antigens from Streptococcus mutans serotypes a and d: characterization of multiple antigenic determinants.

The polysaccharide antigen preparations from serotype a and serotype d strains of Streptococcus mutans contained both a serotype-specific antigenic determinant and a common a-d antigenic determinant, as demonstrated by agar gel diffusion studies and a quantitative cross-precipitin assay. The chromatographically purified antigens were isolated by a method which depended on their serological specificity to determine if these two antigenic determinants were located on the same molecule. The a and d polysaccharides were recovered from specific antigen-antibody complexes and characterized with respect to their immunological specificity and chemical composition. Agar gel diffusion tests demonstrated that, in both the a and d preparations, the serotype-specific antigenic determinant and the common a-d antigenic determinant were present in one molecule.

Animals↗
PubMed1975

Production and properties of an extracellular bacteriocin from Streptococcus mutans bacteriocidal for group A and other streptococci.

An extracellular bacteriocidal substance is produced by a serotype c strain of Streptococcus mutans in liquid meduim during the stationary phase of growth. The lethal effect of the substance was demonstrated by the decrease in viable counts of a standardized suspension of group A streptococci in broth. No lysis of affected cells was observed and no changes in appearance of these cells was seen in electron micrographs. The material was effective against certain strains of immmunological groups A, C, D, G, H, L, and O streptococci. It was inactive against strains of S. mutans belonging to the a, b, c, and d serotypes, Bacillus subtilis, Staphylococcus aureus, Pseudomonas aeruginosa, and Escherichia coli. The factor was purified 273-fold from the culture fluid by column chromatography. It was sensitive to trysin and Pronase and resistant to catalase. It possessed a molecular weight of more than 20,000 and was not dialyzable. The properties of this substance indicate that it is a bacteriocin. Group A streptococci, which had been treated with antiserum specific for the cell wall group and type antigens, were susceptible to the bacteriocin. Streptococcal strains resistant to the lethal action of the bacteriocin adsorbed the bacteriocin from the solutions, as did the sensitive cells. The bacteriocin was not adsorbed at 0 C.

Adsorption↗