Molecular Structure of the Outermost Cell Wall Component of Spirillum Serpens

1977 ◽  
Vol 35 ◽  
pp. 342-343
Author(s):  
Wah Chiu ◽  
David Grano
Keyword(s):  
Molecular Structure ◽  
Cell Wall ◽  
Outer Membrane ◽  
Gel Electrophoresis ◽  
Electron Microscopic Examination ◽  
Electron Microscopic ◽  
Cell Wall Component ◽  
Protein Components ◽  
Exposure Technique ◽  
Structural Aspects

The periodic structure external to the outer membrane of Spirillum serpens VHA has been isolated by similar procedures to those used by Buckmire and Murray (1). From SDS gel electrophoresis, we have found that the isolated fragments contain several protein components, and that the crystalline structure is composed of a glycoprotein component with a molecular weight of ∽ 140,000 daltons (2). Under an electron microscopic examination, we have visualized the hexagonally-packed glycoprotein subunits, as well as the bilayer profile of the outer membrane. In this paper, we will discuss some structural aspects of the crystalline glycoproteins, based on computer-reconstructed images of the external cell wall fragments.The specimens were prepared for electron microscopy in two ways: negatively stained with 1% PTA, and maintained in a frozen-hydrated state (3). The micrographs were taken with a JEM-100B electron microscope with a field emission gun. The minimum exposure technique was essential for imaging the frozen- hydrated specimens.

The binding of Pseudomonas aeruginosa outer membrane ghosts to human buccal epithelial cells

1986 ◽  
Vol 32 (2) ◽  
pp. 160-166 ◽  
Author(s):  
P. Doig ◽  
A. L. Franklin ◽  
R. T. Irvin
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Epithelial Cells ◽  
Outer Membrane ◽  
Copy Number ◽  
Electron Microscopic Examination ◽  
Equilibrium Analysis ◽  
Metabolic Effects ◽  
Electron Microscopic ◽  
Buccal Epithelial Cells ◽  
Number Class

The binding of outer membrane (OM) ghosts derived from Pseudomonas aeruginosa strain 492c to human buccal epithelial cells (BECs) was examined. Electron microscopic examination of the binding of OM ghosts to BECs revealed direct OM ghost–BEC interaction. Equilibrium analysis of the binding of OM ghosts to trypsinized BECs employing the Langmuir adsorption isotherm indicated the number of binding sites (iV) to be 1.3 × 10−1 μg protein per BEC with an apparent association constant (Ka) of 3.4 × 10−2 mL/μg protein. The Langmuir analysis of binding of OM ghosts to untrypsinized BECs was complex, suggesting two possible classes of receptors, a high affinity–low copy number class (Ka, 1.8 × 10−2 mL/μg protein; N, 8.6 × 10−5 μg protein per BEC) and a low affinity – high copy number class(Afa, 3.7 × 10−3 mL/μg protein; N, 9.2 × 10−4 μg protein per BEC). Sugar inhibition studies incorporating D-galactose enhanced binding to each BEC type. N-Acetylneuraminic acid and N-acetyl-glucosamine both enhanced binding of OM ghosts to untrypsinized BECs, while inhibiting binding to trypsinized BECs. D-Arabinose inhibited binding to both BEC types. Binding of OM ghosts to both BEC types was greatly inhibited by D-fucose, while L-fucose only greatly inhibited binding to untrypsinized BECs. These sugar inhibition data demonstrated a difference in the binding of OM ghosts to trypsinized and untrypsinized BECs and possibly reveal the nature of the receptor(s), free of possible bacterial metabolic effects. These data indicated that OM ghosts from 492c appear to bind to BECs in a similar manner to the intact bacteria and represent a simple model system to study the adhesion of P. aeruginosa to BECs.

A comparison of the effects of several antifungal imidazole derivatives and polyenes on Candida albicans: an ultrastructural study by scanning electron microscopy

1982 ◽  
Vol 28 (10) ◽  
pp. 1119-1126 ◽  
Author(s):  
M. Bastide ◽  
S. Jouvert ◽  
J.-M. Bastide
Keyword(s):  
Electron Microscopy ◽  
Cell Wall ◽  
Candida Albicans ◽  
Cytoplasmic Membrane ◽  
Electron Microscopic Examination ◽  
Yeast Cells ◽  
Electron Microscopic ◽  
Imidazole Derivatives ◽  
Scanning Electron Microscopic ◽  
Scanning Electron

The early events in the interaction of two polyene (amphotericin B and nystatin) and five imidazole (clotrimazole, ketoconazole, miconazole, isoconazole, and econazole) antimycotics used at fungicidal concentrations with the surface of Candida albicans were studied by scanning electron microscopic examination of treated intact young yeast cells, treated spheroplasts, and spheroplasts liberated from treated young yeast cells. In all cases, treatment lasted 2 h. The polyenes passed through the yeast cell wall and interacted with the cytoplasmic membrane causing the spheroplasts to lose their characteristic spheric form and to liberate their contents. Clotrimazole caused the formation of numerous circular openings in the cytoplasmic membrane, but only when the agent was used to treat spheroplasts directly. Ketoconazole, miconazole, isoconazole, and econazole interacted with the cell wall causing formation of convolutions and wrinkles. The three imidazole derivatives that are structurally closely related, miconazole, isoconazole, and econazole, inhibited the enzyme-catalyzed release of spheroplasts from young yeast cells.

Electrophoretic and electron microscopic examination of the adductor and diductor muscles of an articulate brachiopod, Terebratalia transversa

1982 ◽  
Vol 60 (4) ◽  
pp. 550-559 ◽  
Author(s):  
William P. Eshleman ◽  
Jerrel L. Wilkens ◽  
Michael J. Cavey
Keyword(s):  
Gel Electrophoresis ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Electron Microscopic Examination ◽  
Light Chains ◽  
Electron Microscopic ◽  
Electrophoretic Patterns ◽  
Transmission Electron ◽  
Adductor Muscles ◽  
Regulation Of Contraction

The proteins of the striated adductor muscles, smooth adductor muscles, and diductor muscles of the articulate brachiopod Terebratalia transversa have been examined by sodium dodecyl sulfate – polyacrylamide gel electrophoresis. Electrophoretic patterns indicate the presence of paramyosin in all of these valve muscles. Tentative identification has also been made of the proteins responsible for actin and for myosin regulation of contraction (troponin–tropomyosin and myosin light chains, respectively). The myofilaments of the striated adductor cells, smooth adductor cells, and diductor cells have been characterized by transmission electron microscopy. The smooth adductor cells and the diductor cells exhibit very thick myofilaments which are fusiform in shape, exceptionally long, and axially banded. Morphological features of these thick myofilaments are consistent with those of paramyosin filaments found in other muscles and myoepithelia. Although the striated adductor cells contain paramyosin, it is not manifest in the thick myofilaments.

scholarly journals Two Types of Bacteria Adherent to Bovine Respiratory Tract Ciliated Epithelium

1993 ◽  
Vol 30 (1) ◽  
pp. 12-19 ◽  
Author(s):  
A. T. Hastie ◽  
L. P. Evans ◽  
A. M. Allen
Keyword(s):  
Cell Wall ◽  
Microscopic Examination ◽  
Lectin Binding ◽  
Electron Microscopic Examination ◽  
Tracheal Epithelium ◽  
Ciliated Cells ◽  
Electron Microscopic ◽  
Department Of Agriculture ◽  
Immunogold Staining ◽  
Transmission Electron

Two hundred sixty tracheas were obtained from a Philadelphia abattoir under permit from the Department of Agriculture; the tracheas were excised from predominantly Holstein calves of both sexes that weighed approximately 250 kg. Tracheas were transported in normal saline to the laboratory at Thomas Jefferson University, Philadelphia, Pennsylvania. Evidence of bacteria adherent to the tracheal epithelium was found in specimens from 20/24 of these tracheas. The epithelium from each of five tracheas was placed in glutaraldehyde fixative for transmission electron microscopic examination. Epithelium from each of 12 other tracheas was placed in formaldehyde fixative for light microscopic examination. Microscopically, 13 of these 17 bovine tracheal epithelia were observed to contain bacteria located longitudinally parallel to and between cilia and microvilli of ciliated cells. Preparations of ciliary axonemes isolated from the epithelium of seven additional bovine tracheas also contained these bacteria in sections viewed by a transmission electron microscope. These bacteria had two different ultrastructural morphologies: filamentous with a trilaminar-structured cell wall and short with a thick, homogeneously stained cell wall beneath a regularly arrayed surface layer. The short bacillus had surface carbohydrates, including mannose, galactose, and N-acetylgalactosamine, identified by lectin binding. The filamentous bacillus was apparently externally deficient in these carbohydrates. Immunogold staining revealed that the filamentous bacillus was antigenically related to cilia-associated respiratory (CAR) bacillus, which has been identified in rabbit and rodent species. Significantly decreased numbers of cilia were obtained from tracheal epithelium heavily colonized by the filamentous bacilli, suggesting a pathologic change in ciliated cells.

Etude des polypeptides de structure du virus iridescent de Chilo suppressalis (Iridovirus type 6)

1979 ◽  
Vol 25 (7) ◽  
pp. 841-849 ◽  
Author(s):  
Sylvie Barray ◽  
Gerard DeVauchelle
Keyword(s):  
Microscopic Examination ◽  
Gel Electrophoresis ◽  
Electron Microscopic Examination ◽  
Chilo Suppressalis ◽  
Purification Procedure ◽  
Chilo Iridescent Virus ◽  
Electron Microscopic ◽  
Iridescent Virus ◽  
Molecular Weights ◽  
Artificial Mixtures

We report a procedure for the purification of Chilo iridescent virus (Iridovirus type 6), an evaluation of the purification procedure, and the results of analyses of the virion proteins by acrylamide gel electrophoresis. Purity was evaluated in three ways, i.e., by analysis of purified virions from artificial mixtures of infected and labeled uninfected larvae, electrophoresis at neutral pH, and electron-microscopic examination. Analysis of the polypeptides of purified CIV gave the following results: (i) after solubilization with SDS-B-mercaptoethanol, 16 polypeptides could be resolved in Coomassie brillant blue-stained electrophoretograms with molecular weights ranging from 18 000 to 115 000; (ii) after solubilization with SDS-urea, 26 polypeptides could be resolved with molecular weights ranging from 10 000 to 230 000 daltons.

The novel structure of a microorganism of human gingival plaque

1974 ◽  
Vol 20 (10) ◽  
pp. 1307-1309 ◽  
Author(s):  
Nagi Halhoul ◽  
J. Ross Colvin
Keyword(s):  
Cell Wall ◽  
Microscopic Examination ◽  
Electron Microscopic Examination ◽  
Extracellular Polysaccharide ◽  
The Novel ◽  
Electron Microscopic ◽  
Individual Fiber ◽  
Novel Structure ◽  
Pass Through

Electron-microscopic examination of gingival plaque microflora showed a bacillus-like, microencapsulated, thick-walled organism with a previously unreported structure. This structure, which is not an example of fimbriae, flagellae, or attached extracellular polysaccharide, is a tuft of thin fibers about 0.3 μm long at only one end of the cell. The fibers begin in or near to the cell wall and pass through the microcapsule to the outside. The name lotussy is proposed for this new structure and the name lotuslifa for an individual fiber or filament.

An Electron Microscope Study of the Outer Layers of Barley Leaves Infected with Rhynchosporium secalis

1974 ◽  
Vol 1 (2) ◽  
pp. 313 ◽  
Author(s):  
CC Ryan ◽  
CJ Grivell
Keyword(s):  
Cell Wall ◽  
Outer Layer ◽  
Electron Microscope Study ◽  
Electron Microscopic Examination ◽  
Ruthenium Red ◽  
Electron Microscopic ◽  
Before And After ◽  
Barley Leaves ◽  
Epidermal Cell Wall ◽  
Wall Following

An electron microscopic examination was made of barley leaves before and after infection by R. secalis. Ruthenium red was used as an electron-opaque stain for pectic material. In uninfected leaves the adaxial surface consisted of wax, cuticle, pectic and inner and outer layer of the epidermal cell wall. Following penetration, infecting hyphae grew between the pectic layer and outer layer of the epidermal wall. The pectic and cuticular layers remained largely intact in leaf lesions until conidia were produced, whereas the cell wall was degraded and replaced by hyphae.

Chemistry and Organization of Aleurone Cell Wall Components From Wheat and Barley

1981 ◽  
Vol 8 (5) ◽  
pp. 475 ◽  
Author(s):  
A Bacic ◽  
BA Stone
Keyword(s):  
Cell Wall ◽  
Electron Microscopic Examination ◽  
Alkaline Media ◽  
Methylation Analysis ◽  
Electron Microscopic ◽  
Aleurone Cell ◽  
Transmission Electron ◽  
Covalent Interactions ◽  
Differential Solubility ◽  
Wall Components

Methylation analysis and hydrolysis with specific enzymes indicates that aleurone cell wall preparations from wheat (Triticum aestivum cv. Insignia) and barley (Hordeum vulgare cv. Clipper) are composed of two main types of polysaccharides, heteroxylans and 1,3;1,4-β-glucans. Small amounts of glucomannan and cellulose are also present. Approximately 1% of a 1,3-β-glucan was also detected in the wall preparations using a specific 1,3-β-glucan exohydrolase. This material probably corresponds to the aniline blue-fluorescent deposits seen at the aleurone-endosperm interface. As isolated, the aleurone wall preparations are associated with protein, 10.5% in wheat and 16.0% in barley. Electron microscopic examination and amino acid analyses indicated that a major part of this protein arises from cytoplasmic protein deposited on the walls during isolation in organic solvents. Fractionation of the walls by conventional procedures showed that the heteroxylan and 1,3 ;1,4-β-glucan components were extracted by water, 8 M urea and alkaline solvents. Their differential solubility is discussed in terms of their structural organization and possible covalent interactions between polymers. Transmission electron microscopy of the walls at each stage of fractionation showed that the bilayered organization was retained after water and 8 M urea extraction but was lost following extraction in alkaline media.

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