Evidence for motility-related fimbriae in the gliding microorganism Myxococcus xanthus

1976 ◽  
Vol 22 (10) ◽  
pp. 1589-1593 ◽  
Author(s):  
Thomas H. MacRae ◽  
Howard D. McCurdy
Keyword(s):  
Microscopic Examination ◽  
Myxococcus Xanthus ◽  
Electron Microscopic Examination ◽  
Electron Microscopic ◽  
Cell Lysates ◽  
Myxococcus Virescens

An electron-microscopic examination of negatively stained preparations from cell lysates of Myxococcus xanthus and in situ samples of Myxococcus xanthus, Myxococcus virescens, and Myxococcus fulvus has demonstrated the presence of polar fimbriae, about 8.5 nm in diameter, on motile but not nonmotile cells.

scholarly journals Localization of DNA in Ultrascopic Nuclear Appendages of Polymorphonuclear White Blood Cells from Patients with Low Serum B12

2002 ◽  
Vol 50 (10) ◽  
pp. 1381-1388 ◽  
Author(s):  
Robert W. Bunting ◽  
Martin K. Selig
Keyword(s):  
Microscopic Examination ◽  
Blood Cells ◽  
White Blood Cells ◽  
Serum Vitamin ◽  
Electron Microscopic Examination ◽  
Vitamin B ◽  
Electron Microscopic ◽  
Ultrastructural Finding ◽  
Low Serum

Polymorphonuclear white blood cells from patients with low serum vitamin B12 (cobalamin) have ultrascopic appendages that project from their nuclear membranes. These appendages are most often found in the shape of blebs and stalks. Cytoplasmic rings that may be separated from the nucleus have also been seen. There is no known function for these appendages. Blood from 11 patients with low serum B12 was processed for electron microscopic examination. In situ end-labeling of DNA and subsequent electron microscopic examination were performed. DNA was localized in all of the visualized appendages and rings. Treatment with DNases I and II decreased the labeling of these appendages by 63%. These DNA-laden appendages are a unique ultrastructural finding and may function to transfer fragmented DNA, which occurs in vitamin B12 deficiency, from the nucleus into the cytoplasm.

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.

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.

Sign in / Sign up

Export Citation Format

Share Document