RESUMEN
The cellular fatty acid compositions of 26 strains of methicillin-resistant Staphylococcus aureus (MRSA) and 17 strains of methicillin-susceptible S. aureus (MSSA) were analyzed by gas-liquid chromatography. The fatty acid compositions of the two groups were very similar with 16 identified components. The major fatty acids were Ci14 = 0, Ci15 = 0, C18 = 0 and C20 = 0. Among these fatty acids, the percentage of the Ci15 = 0 fatty acid component of MRSA strains (11.4 +/- 3.9%) was statistically higher than that of MSSA strains (6.2 +/- 2.4%) (p < 0.001). On the other hand, the percentage of the C20 = 0 fatty acid components of MRSA strains (20.2 +/- 8.8%) was statistically lower than that of MSSA strains (30.7 +/- 10.4%) (p < 0.001). The production of beta-lactamase and beta-hemolysin in both groups' strain was also unrelated to the relative amounts of the fatty acid components. These results indicated a statistical tendency for the percentage fatty acid compositions of the MRSA strains to be quantitatively different from those of the MSSA for both the Ci15 = 0 and C20 = 0 fatty acid components. Analysis of the fatty acid compositions may have an application in the differentiation of MRSA and MSSA strains.
Asunto(s)
Antibacterianos/toxicidad , Ácidos Grasos/análisis , Resistencia a la Meticilina , Meticilina/toxicidad , Staphylococcus aureus/química , Staphylococcus aureus/efectos de los fármacos , Cromatografía de Gases , Proteínas Hemolisinas/biosíntesis , Pruebas de Sensibilidad Microbiana , Especificidad de la Especie , Staphylococcus aureus/fisiología , beta-Lactamasas/biosíntesisRESUMEN
The cellular fatty acids and aldehydes of oral Eubacterium species were determined by gas chromatography-mass spectrometry. E. brachy and E. lentum contained mainly branched-chain fatty acids, whereas the others contained straight-chain acids. E. brachy, E. lentum, E. yurii ssp. yurii, E. yurii spp. margaretiae, E. limosum, E. plauti and E. aerofaciens also contained aldehydes with even carbon numbers. In addition to species-specific components, the compositional ratios of fatty acids and aldehydes characterized each individual species. The 10 species tested were divided into 5 groups by the principal component analysis. Cellular fatty acids and aldehydes would be chemical markers for interspecies differentiation of oral Eubacterium.
Asunto(s)
Aldehídos/análisis , Eubacterium/química , Ácidos Grasos/análisis , Técnicas de Tipificación Bacteriana , Eubacterium/clasificación , Humanos , Boca/microbiologíaRESUMEN
In a series of investigations into the cariogenicity of Streptococcus mutans, we studied the incorporation of exogenous fatty acids with reference to glucosyltransferase secretion and membrane fatty acid changes. When cells were grown with different fatty acids, both saturated and unsaturated fatty acids were readily incorporated into the membrane lipids and were biotransformed and elongated preferentially to the longer 16- and 18-carbon-chain fatty acids. This incorporation and chain-elongation led to significant changes in fatty acids composition. By adding fatty acids to the medium, it was possible to appropriately modify the degree of unsaturation and the relative ratio between specific fatty acids in the membrane lipids of S. mutans.
Asunto(s)
Ácidos Grasos/farmacocinética , Streptococcus mutans/metabolismo , Ácidos Grasos/análisis , Lípidos de la Membrana/análisisRESUMEN
We tested antibacterial and antiviral activities of rat cystatin S, a cysteine proteinase inhibitor, belonging to the family 2 cystatins against 18 different bacterial species and poliovirus type 1 (Sabin). Rat cystatin S specifically inhibited the growth of a human oral anaerobic bacterium Porphyromonas gingivalis due to a bactericidal effect.
Asunto(s)
Cistatinas/farmacología , Inhibidores de Cisteína Proteinasa/farmacología , Porphyromonas gingivalis/efectos de los fármacos , Secuencia de Aminoácidos , Animales , Bacterias/efectos de los fármacos , Cistatinas/química , Cistatinas/aislamiento & purificación , Humanos , Pruebas de Sensibilidad Microbiana , Datos de Secuencia Molecular , Poliovirus/efectos de los fármacos , Señales de Clasificación de Proteína/química , Señales de Clasificación de Proteína/genética , Ratas , Cistatinas Salivales , Especificidad de la Especie , Streptococcus pyogenes/efectos de los fármacosRESUMEN
The polypeptides of seven strains of human treponemes were investigated by immunoblot analysis for their binding to the human placental collagens and laminin. Of the treponemal polypeptides, eleven polypeptides, 45-kDa, 49-kDa, and 62-kDa polypeptides from T. pallidum ATCC 27087, a 48-kDa polypeptide from T. phagedenis biotype Reiter, 51-kDa and 53-kDa polypeptides from T. vincentii ATCC 35580, 30-kDa, 53-kDa and 63-kDa polypeptides from T. socranskii subsp. buccale ATCC 35534, a 52-kDa polypeptide from T. denticola ATCC 35405, and a 53-kDa polypeptide from T. denticola ATCC 33520 possessed an ability to bind to the laminin, type I, III, IV, or V collagen. An intermediate-sized human oral isolate strain G7201 did not possess any laminin- or collagen-binding polypeptides. Immunoelectron microscopy using intact treponemal cells with a single collagen-binding polypeptide and the corresponding antisera demonstrated that the 51-kDa and 53-kDa polypeptides from T. vincentii, the 53-kDa polypeptide from T. socranskii subsp. buccale ATCC 35534 and the 52-kDa polypeptide from T. denticola ATCC 35405, were outer envelope proteins.
Asunto(s)
Adhesión Bacteriana , Proteínas Bacterianas/metabolismo , Colágeno/metabolismo , Laminina/metabolismo , Treponema/fisiología , Electroforesis en Gel de Poliacrilamida , Humanos , Immunoblotting , Inmunohistoquímica , Microscopía Inmunoelectrónica , Peso Molecular , Treponema/metabolismo , Treponema/ultraestructuraRESUMEN
The surface and inner structure of the spherical bodies (SB) produced by the human oral treponeme strain G7201, similar to Treponema macrodentium, were studied by electron microscopy. Ultrathin sectioning and scanning techniques demonstrated that in the presence of a high concentration of sucrose, the outer envelope of one or both terminal ends of this oral spirochete changed into a swollen structure, the SB. Spirochetal cells adhered firmly to the surface of the resultant body. The membrane of the SB, i.e. the outer envelope, enclosed the coiled protoplasmic cylinder and five axial fibrils which were located between the envelope and th cylinder. Large expanded protoplasmic cylinders were observed, surrounded by a partially disrupted double membrane in some SBs. A number of frizzly fibrous structures, which differed from axial fibrils in number and shape, were also observed within these SBs. Except for abnormal or partially broken cylinders, the protoplasmic cylinders tended to be located close to the inner surface of the SB membrane, resulting in a central vacant space with occasional axial fibrils. These findings suggest that the oral spirochete produces an SB by terminal expansion of the outer envelope in the presence of high concentrations of sucrose. The outer envelope of the SB, which consists of two electron-dense layers, has the property of binding spirochetal cells to its outer layer and the protoplasmic cylinder and axial fibrils to the inner layer. Some protoplasmic cylinders were also observed to be swollen in the presence of high sucrose concentrations.
Asunto(s)
Boca/microbiología , Spirochaetales/ultraestructura , Microscopía Electrónica , Sacarosa/farmacologíaRESUMEN
We attempted to determine whether or not Yersinia enterocolitica could invade two cell lines derived from Burkitt's lymphoma (BL), P3HR-1, and Raji cells, and if the expression of Epstein-Barr virus (EBV) genome could be activated by the invasion of the organisms into the cells. The invasiveness of Y. enterocolitica into BL cells was examined morphologically, using transmission and scanning electron microscopy, and the induction of EBV antigens in the BL cells was examined by indirect immunofluorescence. Y. enterocolitica was clearly observed to invade P3HR-1 and Raji cells within 2 hr incubation at 37 degrees, after bacterial challenge. However, the invaded BL cells did not show significant induction of EBV early antigen after cultivation for 72 hr at 37 degrees. Although the present experiment failed to yield positive findings pertaining to the activation of EBV genome, our experimental system per se may still be a useful model when attempting to assess the effects of invading bacteria on the viral genome persistently carried in the host cells.
Asunto(s)
Linfoma de Burkitt/microbiología , Yersinia enterocolitica/patogenicidad , Linfoma de Burkitt/ultraestructura , Línea Celular , Técnica del Anticuerpo Fluorescente , Humanos , Microscopía Electrónica , Microscopía Electrónica de Rastreo , Yersinia enterocolitica/aislamiento & purificación , Yersinia enterocolitica/ultraestructuraRESUMEN
The colonial morphology of three strains of cultivable, nonpathogenic treponemes including a human oral treponeme was examined by light and electron microscopy. Treponema phagedenis strains Kazan and Reiter produced large white colonies on the surface of solid media composed of sterility test broth, 0.9 to 3.1% agar, rifampin, and 12.5% rabbit or horse serum. A human oral treponeme, strain G7201 , grew as diffused white zones on 0.9 to 3.1% agar plates. Under the cultural conditions employed agar concentrations slightly affected the time of appearance of colonies of the three strains of treponemes. When the colonies of these three strains were viewed by scanning electron microscopy, differences in their colonial morphology were observed. The 11-day-old colonies of human oral strain G7201 were very small, 5 to 15 micron in diameter, and had a slight irregular border. Kazan treponemes developed circular, entire and low convex colonies. Scanning and transmission electron microscopy revealed that the colonies of Reiter treponemes contained spherical forms almost up to 5 micron in diameter, each consisting of an outer membrane and a treponemal main body. They were very similar to the spherical bodies produced by strain G7201 in sucrose-containing broth.
Asunto(s)
Treponema/citología , Agar , Animales , Medios de Cultivo , Caballos , Humanos , Microscopía Electrónica , Microscopía Electrónica de Rastreo , Conejos , Treponema/aislamiento & purificación , Treponema/ultraestructuraRESUMEN
The effects of n-butyrate and/or 12-O-tetradecanoylphorbol-13-acetate (TPA) on Raji and P3HR-1 cells were examined using electron microscopy. n-Butyrate treatment caused a decrease in the number and elongation of surface microvilli. In addition, well-developed rough endoplasmic reticulum and a marked decrease in condensed chromatin clumps were observed in the nucleus. The filamentous structures and nuclear membrane-like structures, which were not reported previously, appeared occasionally in the nucleus. On the other hand, in the cells treated with TPA no marked morphological changes were observed except the higher cytoplasmic:nuclear ratio. n-Butyrate-induced morphological changes were not inhibited when combined with TPA or retinoic acid. Electron microscopic studies showed remarkable differences in morphological change in these cells treated with n-butyrate and/or TPA.
Asunto(s)
Butiratos/farmacología , Linfocitos/efectos de los fármacos , Forboles/farmacología , Acetato de Tetradecanoilforbol/farmacología , Antígenos Virales/análisis , Ácido Butírico , División Celular/efectos de los fármacos , Línea Celular , Herpesvirus Humano 4/inmunología , Humanos , Linfocitos/inmunología , Linfocitos/ultraestructura , Microscopía Electrónica , Microscopía Electrónica de Rastreo , Microscopía de Contraste de Fase , Tretinoina/farmacologíaRESUMEN
The ability of spirochetes to adhere to collagens was compared among three species of human oral treponemes. Immunoblot analysis demonstrated that type I-, IV-, and V-collagen-binding polypeptides (CBPs) were detected in the heated and unheated preparations from both Treponema denticola ATCC 33520 and T. socranskii subsp. buccale ATCC 35534. Few CBPs, however, were detected in the heated and unheated preparations from a recently characterized isolate, T. medium strain G7201. Immunoelectron microscopy using rabbit antisera against the CBPs from the unheated preparations demonstrated that four CBPs, a 27 kDa type V-CBP of T. denticola ATCC 33520, a 95 kDa type IV-CBP and a 110 kDa type I-CBP of T. socranskii subsp. buccale ATCC 35534, and a 95 kDa type IV-CBP of T. medium strain G7201, were located on the outer envelopes of the individual cells. The adherence of T. denticola to the collagen-coated surfaces was significantly greater than that of T. medium, suggesting that the CBPs on the oral spirochetal cells play an important role in their adherence to collagen-rich connective tissues of the host.
Asunto(s)
Adhesión Bacteriana , Proteínas de la Membrana Bacteriana Externa/análisis , Proteínas Portadoras/análisis , Colágeno/metabolismo , Treponema/química , Treponema/fisiología , Proteínas de la Membrana Bacteriana Externa/inmunología , Proteínas de la Membrana Bacteriana Externa/aislamiento & purificación , Proteínas de la Membrana Bacteriana Externa/metabolismo , Proteínas Portadoras/metabolismo , Electroforesis en Gel de Poliacrilamida , Calor , Humanos , Immunoblotting , Microscopía Electrónica , Péptidos/análisis , Unión Proteica , Treponema/inmunologíaRESUMEN
The osmium-dimethyl sulfoxide-osmium method for clear visualization of intracellular structure was used to observe the detailed inner structure of the spherical bodies produced in vitro by a human oral treponeme. Scanning electron microscopy of the cracked spherical body revealed no morphological differences between the outer and inner surfaces of the spherical body membrane, and that multiple folded or somewhat linear main bodies adhere closely to the inner surface. In addition, axial flagella partially free from the main bodies spread widely within the body to make a network, and a number of blebs ranging from approximately 1 micrometer to 0.2 micrometer in diameter were located near the terminal or subterminal areas of the main bodies. The origin of the blebs and the mechanism of spherical body formation are discussed.
Asunto(s)
Treponema/ultraestructura , Microscopía Electrónica de Rastreo , Enfermedades de la Boca/microbiología , Infecciones por Treponema/microbiologíaRESUMEN
Major polypeptides from a human oral spirochete Treponema denticola ATCC 33520 were examined to demonstrate their ability to bind to human plasma fibronectin by immunoblot analysis. Of three main polypeptides separated on sodium dodecyl sulfate polyacrylamide gels 53,000-daltons (53-kDa) and 72-kDa surface antigenic proteins and a 38-kDa axial flagellar protein showed the ability to bind to fibronectin, suggesting that fibronectin on host cells can mediate cytoadherence of T. denticola by its binding to the surface proteins or the exposed 38-kDa axial flagellar protein.
Asunto(s)
Adhesinas Bacterianas , Proteínas de la Membrana Bacteriana Externa/metabolismo , Proteínas Bacterianas , Proteínas Portadoras , Treponema/metabolismo , Secuencia de Aminoácidos , Antígenos Bacterianos/química , Antígenos Bacterianos/metabolismo , Adhesión Bacteriana/fisiología , Proteínas de la Membrana Bacteriana Externa/química , Proteínas de la Membrana Bacteriana Externa/inmunología , Sitios de Unión , Fibronectinas/química , Fibronectinas/metabolismo , Humanos , Immunoblotting , Técnicas In Vitro , Datos de Secuencia Molecular , Peso Molecular , Boca/microbiología , Oligopéptidos/química , Oligopéptidos/metabolismo , Oligopéptidos/farmacología , Treponema/inmunología , Treponema/aislamiento & purificaciónRESUMEN
Human oral spirochetes are prominent inhabitants of subgingival plaque in patients with periodontal disease. By immunoelectron microscopy using protein A-gold complexes and either polyclonal mouse antiserum against the 53-kDa antigen or 53-kDa-antigen-specific monoclonal antibody, a major polypeptide antigen, with a molecular weight of 53,000 (molecular size, 53 kilodaltons [kDa]), of a human oral spirochete, Treponema denticola ATCC 33520, was found to localize on the surface of the outer envelope.
Asunto(s)
Antígenos Bacterianos/aislamiento & purificación , Antígenos de Superficie/aislamiento & purificación , Treponema/inmunología , Pruebas de Aglutinación , Anticuerpos Antibacterianos , Anticuerpos Monoclonales , Especificidad de Anticuerpos , Antígenos Bacterianos/inmunología , Antígenos de Superficie/inmunología , Humanos , Inmunohistoquímica , Microscopía Electrónica , Enfermedades Periodontales/microbiología , Enfermedades Periodontales/patología , Treponema/ultraestructuraRESUMEN
We examined the genetic characteristics of a human oral treponeme isolated from subgingival plaque of a patient with periodontal disease that could not be assigned to any of the previously described oral Treponema species. The guanine-plus-cytosine content of its DNA was 51 mole%. The levels of DNA-DNA relatedness of the organism to other Treponema species, including Treponema denticola, Treponema vincentii, Treponema socranskii, Treponema pallidum and Treponema phagedenis, were less than 30%. This study clearly demonstrated that the isolated treponeme could be completely distinct from the established oral Treponema species genetically. Also, the study indicated remarkable genetic heterogeneity among human oral Treponema species.
Asunto(s)
Placa Dental/microbiología , Treponema/genética , Citosina/análisis , ADN Bacteriano/química , Heterogeneidad Genética , Guanina/análisis , Humanos , Masculino , Persona de Mediana Edad , Hibridación de Ácido Nucleico , Periodontitis/microbiología , Homología de Secuencia de Ácido Nucleico , Treponema/clasificación , Treponema/aislamiento & purificaciónRESUMEN
The morphological changes which occur in Raji cells during EBV induced fusion are described. Of particular interest is the formation of local contacts between cells, at these points the plasmalemmae of the two cells become disorganized and cytoplasmic bridges are formed.
Asunto(s)
Butiratos/farmacología , Fusión Celular , Herpesvirus Humano 4/fisiología , Forboles/farmacología , Acetato de Tetradecanoilforbol/farmacología , Ácido Butírico , Fusión Celular/efectos de los fármacos , Células Cultivadas , Infecciones por Herpesviridae/patología , Humanos , Linfocitos/ultraestructura , Microscopía ElectrónicaRESUMEN
1. Both Tween 80 and sodium fluoride significantly enhanced total extracellular glucosyltransferase activities of Streptococcus mutans. 2. Water-insoluble and water-soluble glucan formation were uniformly increased by Tween 80, whereas fluoride stimulated only water-soluble glucan formation. 3. Elevated glucan formation was due to an increase in enzymes secreted from bacterial cells. 4. Fatty acid composition and phospholipid content in bacterial membrane were changed by Tween 80, although sodium fluoride scarcely showed these changes. 5. Comparative results suggest that modulation of membrane lipids participates in mutansucrase production but not in dextransucrase production of S. mutans.
Asunto(s)
Glucosiltransferasas/biosíntesis , Polisorbatos/farmacología , Fluoruro de Sodio/farmacología , Streptococcus mutans/enzimología , Lípidos de la Membrana/metabolismo , Streptococcus mutans/efectos de los fármacosRESUMEN
Two polypeptide antigens with molecular sizes of 34,000 daltons (34 kDa) and 38 kDa were separated from heated cells of a human clinical treponeme strain G7201 and Treponema denticola ATCC 35404, respectively. The rabbit polyclonal antisera against these antigens were produced and examined for their immunological reactions with the two heated antigens or intact spirochetal cells. Immunoblot analysis showed that the 34-kDa protein was also detected in T. denticola ATCC 35404 and ATCC 33520, and the 38-kDa protein was detected only in the two ATCC strains. Immunoelectron microscopy using the two rabbit antisera and protein A-gold complexes demonstrated that the 38-kDa protein antigen was present on the axial flagella of two T. denticola strains, and that the 34-kDa protein was located in the axial flagella of the G7201 cell, but neither in axial flagella nor on outer envelopes of the two ATCC strains cells, suggesting that the native 34-kDa axial flagellar protein of the G7201 strain may be different from that of T. denticola in terms of immunological reactivity.