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.

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.

Properties of Isolated Mitochondria of Agaricus Bisporus: Their Relationship to Dormancy and the Germination of Spores

1973 ◽  
Vol 31 ◽  
pp. 458-459
Author(s):  
K. S. McCarty ◽  
R. F. Weave ◽  
L. Kemper ◽  
F. S. Vogel
Keyword(s):  
Mitochondrial Dna ◽  
Ethidium Bromide ◽  
Microscopic Examination ◽  
Agaricus Bisporus ◽  
Osmotic Shock ◽  
Electron Microscopic Examination ◽  
Electron Microscopic ◽  
Isolated Mitochondria ◽  
Dna Strands ◽  
Cytoplasmic Ribosomes

During the prodromal stages of sporulation in the Basidiomycete, Agaricus bisporus, mitochondria accumulate in the basidial cells, zygotes, in the gill tissues prior to entry of these mitochondria, together with two haploid nuclei and cytoplasmic ribosomes, into the exospores. The mitochondria contain prominent loci of DNA [Fig. 1]. A modified Kleinschmidt spread technique1 has been used to evaluate the DNA strands from purified whole mitochondria released by osmotic shock, mitochondrial DNA purified on CsCl gradients [density = 1.698 gms/cc], and DNA purified on ethidium bromide CsCl gradients. The DNA appeared as linear strands up to 25 u in length and circular forms 2.2-5.2 u in circumference. In specimens prepared by osmotic shock, many strands of DNA are apparently attached to membrane fragments [Fig. 2]. When mitochondria were ruptured in hypotonic sucrose and then fixed in glutaraldehyde, the ribosomes were released for electron microscopic examination.

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.

Artifact-free electron microscopic immunocytochemistry on rat brain tissue

1991 ◽  
Vol 49 ◽  
pp. 272-273
Author(s):  
Veronika Burmeister ◽  
N. Ludvig ◽  
P.C. Jobe
Keyword(s):  
Microscopic Examination ◽  
Free Electron ◽  
Electron Microscopic Examination ◽  
Ultrastructural Localization ◽  
Rabbit Serum ◽  
Electron Microscopic ◽  
Electron Microscopic Immunocytochemistry ◽  
Phosphate Buffered Saline ◽  
Rat Brain Tissue ◽  
Immune Rabbit

Electron microscopic immunocytochemistry provides an important tool to determine the ultrastructural distribution of various molecules in both normal and pathologic tissues. However, the specific immunostaining may be obscured by artifactual immunoreaction product, misleading the investigator. Previous observations show that shortening the incubation period with the primary antibody from the generally used 12-24 hours to 1 hour substantially reduces the artifactual immunostaining. We now extend this finding by the demonstration of artifact-free ultrastructural localization of the Ca2/calmodulindependent cyclic nucleotide phosphodiesterase (CaM-dependent PDE) immunoreactivity in brain.Anesthetized rats were perfused transcardially with phosphate-buffered saline followed by a fixative containing paraformaldehyde (4%) and glutaraldehyde (0.25%) in PBS. The brains were removed, and 40μm sections were cut with a vibratome. The sections were processed for immunocytochemistry as described by Ludvig et al. Both non-immune rabbit serum and specific CaM-dependent PDE antibodies were used. In both experiments incubations were at one hour and overnight. The immunostained sections were processed for electron microscopic examination.

Ultrastructural studies of Chlamydia psittaci 6BC variant strains. I. Ultrastructure of the surface layers of egg-passaged 6BC strain

1973 ◽  
Vol 19 (8) ◽  
pp. 887-894
Author(s):  
Linda Poffenroth ◽  
J. W. Costerton ◽  
Nonna Kordová ◽  
John C. Wilt
Keyword(s):  
Chick Embryo ◽  
Microscopic Examination ◽  
Electron Microscopic Examination ◽  
Chlamydia Psittaci ◽  
Gram Negative Bacteria ◽  
Surface Layers ◽  
Electron Microscopic ◽  
Gram Negative ◽  
Ultrastructural Studies ◽  
First Time

Electron microscopic examination of a semipurified Chlamydia psittaci 6BC strain attenuated in chick embryo yolk sac revealed for the first time two morphologically distinct small elementary bodies which differ both in the ultrastructure of their surface layers and in their buoyant densities in sucrose gradients. Also, the morphology of the surface layers of the larger reticulate forms in cell-free systems is described for the first time. Many points of difference between the surface envelopes and internal structure of chlamydial particles and those of Gram-negative bacteria are discussed.

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