Electron microscopy of antibody-labelled cells of <i>Streptococcus mutans</i>

Emyanitoff, Ruth G.; Rucinsky, Thomas E.; Birdsell, Dale C.

doi:10.1139/m76-129

Cited by 3 publications

(2 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To connect the surface projections with the 47-kd protein, we finally studied thin sections of cells treated with antiserum specific to this protein. We selected a method best compatible with preservation of the native structure (Lawn, 1967;Mayyasi et al, 1967;Lai et al, 1973;Emyanitoff, 1976). Thus, the bacteria were treated with antiserum before any fixation.…”

Section: Resultsmentioning

confidence: 99%

A novel virulence-associated cell surface structure composed of 47-kd protein subunits in Yersinia enterocolitica.

Zaleska¹,

Lounatmaa²,

Nurminen³

et al. 1985

The EMBO Journal

View full text Add to dashboard Cite

A fresh human isolate of Yersinia enterocolitica serotype 03, and its derivative that had lost the virulence‐associated 46‐Md plasmid, were grown under defined conditions and compared for their outer membrane protein and cell surface structure. Under these conditions, the virulent strain grown at 37 degrees C expressed one major outer membrane protein (47 kd) not present in the plasmidless strain or in either strain grown at room temperature. A 200‐kd protein also seen in the same preparations was shown to be an oligomer composed of the 47‐kd protein subunits. Four different electron microscopic techniques showed tack‐like projections covering the surface of those bacteria that expressed the 47‐kd protein. These were specifically labeled with antibody to the 47‐kd protein. This surface structure appeared to mediate aggregation (auto‐agglutination) of the bacteria bringing their surfaces into unusually close apposition.

show abstract

Section: Resultsmentioning

confidence: 99%

A novel virulence-associated cell surface structure composed of 47-kd protein subunits in Yersinia enterocolitica.

Zaleska¹,

Lounatmaa²,

Nurminen³

et al. 1985

The EMBO Journal

View full text Add to dashboard Cite

show abstract

“…These filaments were not observed in untreated samples. Perhaps in the presence of specific antibodies these polymers are held in a native, extended configuration, whereas in the course of fixation and dehydration of untreated cells they become attached to the basal structure (Emyanitoff et al, 1976). In an attempt to explain the nature of these filaments, experiments using antibodies against individual moieties of the peptidoglycan molecule are in progress.…”

Section: Discussionmentioning

confidence: 99%

An Electron Microscopic Study of the Location of Peptidoglycan in Group A and C Streptococcal Cell Walls

Wagner

1978

Journal of General Microbiology

View full text Add to dashboard Cite

The morphological appearance of deproteinized Group A and C streptococcal walls after treatment by different procedures extracting teichoic acids and polysaccharides (formamide, hydrochloric acid, nitrous acid, trichloroacetic acid, sulphuric acid, sodium hydroxide and sodium deoxycholate) was compared with the content of teichoic acids and polysaccharides remaining in the treated walls. All procedures extracted teichoic acids almost completely, but polysaccharides were extracted to various degrees. The ultrastructural appearance of walls after these extractions still exhibited the triple-layered wall profile; only a reduction of thickness of the wall and of electron density of the layers occurred. Therz was no direct correlation between the reduction of rhamnose content and thickness of walls.The ultrastructural localization of peptidoglycan in the streptococcal walls was explored by means of the indirect immunoferritin technique using anti-peptidoglycan antibodies isolated from anti-Group A-variant antisera. Ferritin particles were bound predominantly to filamentous structures which protruded from both surfaces of peptidoglycan fragments and isolated walls. Peptidoglycan was also detected on the filamentous protrusions of whole cocci. These results contradict models of the streptococcal wall in which peptidoglycan forms the innermost layer and support a mosaic structure in which peptidoglycan forms a network of the peptidoglycan-polysaccharide complex. INTRODUCTIONThe chemical and morphological structures of the walls of Group A and C streptococci are very similar (Krause & McCarty, 1962;Cole, 1968). Group A streptococcal wall consists of four chemically defined components -proteins (M, T and R), polysaccharide, peptidoglycan and teichoic acid (Swanson et al., 1969). In ultrathin sections three morphologically distinct layers can usually be distinguished (Cole, 1968;Swanson et al., 1969; Wagner & Wagner, 1972~). The wall is composed of an electron-dense inner layer, a middle layer of medium electron density and an outer layer which in most strains is covered by filamentous protrusions. The morphological appearance of the wall, and the fact that proteins can easily be removed by proteolytic enzymes without affecting the viability of the streptococci (Lancefield, 1943) For the extraction studies, the bacteria were grown with shaking in Todd-Hewitt broth (Difco) for 4 h at 37 "C and then treated twice with trypsin (Difco; 0.1 %, w/v, in 0.1 M-phosphate buffer, pH 7.8) at 37 "C for 2 h. After treatment, the organisms were repeatedly washed in 0.1 M-phosphate buffer before being subjected to the different extraction procedures. For the immunoelectron microscopic studies, the bacteria were grown with shaking in Proteose broth at 37 "C overnight, then centrifuged and washed with R-K buffer (Ryter & Kellenberger, 1958).The presence of the Fc-binding factor in these strains was determined by the method of Christensen et al. (1976).Preparation of isolated walls and peptidoglycan. Bacterial suspensions were shaken with ...

show abstract

Possible role of opsonins in adsorption and transport of biological membranes and viruses by staphylococci

Быков¹,

Pashkov²,

Seleznev³

et al. 1986

Bull Exp Biol Med

View full text Add to dashboard Cite

Electron microscopy of antibody-labelled cells of Streptococcus mutans

Abstract: Examination of immune complexes between cells of Streptococcus mutans and homologous antiserum by the techniques of thin-sectioning and freeze-etching revealed that the cells were embedded within and extensive matrix 80-90 nm thick with defined boundaries.

Cited by 3 publications

References 11 publications

A novel virulence-associated cell surface structure composed of 47-kd protein subunits in Yersinia enterocolitica.

A novel virulence-associated cell surface structure composed of 47-kd protein subunits in Yersinia enterocolitica.

An Electron Microscopic Study of the Location of Peptidoglycan in Group A and C Streptococcal Cell Walls

Possible role of opsonins in adsorption and transport of biological membranes and viruses by staphylococci

Contact Info

Product

Resources

About