CYTOLOGY OF PHAGE-INFECTED STREPTOMYCES GRISEUS HYPHAE

1965 ◽  
Vol 11 (1) ◽  
pp. 103-107
Author(s):  
C. M. Gilmour ◽  
E. B. Bradford
Keyword(s):  
Electron Microscopy ◽  
Cell Wall ◽  
Plasma Membrane ◽  
Fine Structure ◽  
Streptomyces Griseus ◽  
Membrane Disruption ◽  
Hexagonal Shape ◽  
Ultrathin Sections ◽  
Irregular Cell

The fine structure of phage-infected Streptomyces griseus hyphae was examined using ultrathin sections and electron microscopy. The intracellular phage was observed to be uniformly distributed throughout the cytoplasm. The diameter and hexagonal shape of the head compared well with shadowed phage preparations. Alterations in fine structure centered on irregular cell wall disintegration, plasma membrane disruption, and leakage of cytoplasmic components.

scholarly journals THE FINE STRUCTURE AND MODE OF ATTACHMENT OF THE SHEATHED FLAGELLUM OF VIBRIO METCHNIKOVII

1963 ◽  
Vol 18 (2) ◽  
pp. 327-336 ◽  
Author(s):  
Audrey M. Glauert ◽  
D. Kerridge ◽  
R. W. Horne
Keyword(s):  
Electron Microscopy ◽  
Cell Wall ◽  
Plasma Membrane ◽  
Fine Structure ◽  
Thin Sections ◽  
Basal Disc ◽  
The Core ◽  
Thin Sectioning ◽  
Potassium Phosphotungstate ◽  
Mode Of Attachment

The sheathed flagellum of Vibrio metchnikovii was chosen for a study of the attachment of the flagellum to the bacterial cell. Normal and autolysed organisms and isolated flagella were studied by electron microscopy using the techniques of thin sectioning and negative staining. The sheath of the flagellum has the same layered structure as the cell wall of the bacterium, and in favourable thin sections it appears that the sheath is a continuation of the cell wall. After autolysis the sheath is usually absent and the core of the flagellum has a diameter of 120 A. Electron micrographs of autolysed bacteria negatively stained with potassium phosphotungstate show that the core ends in a basal disc just inside the plasma membrane. The basal disc is about 350 A in diameter and is thus considerably smaller than the "basal granules" described previously by other workers.

Electron microscopy of two nematode-destroying fungi, Meristacrum asterospermum and Zygnemomyces echinulatus (Meristacraceae, Entomophthorales)

1997 ◽  
Vol 75 (5) ◽  
pp. 762-768 ◽  
Author(s):  
Masatoshi Saikawa ◽  
Masami Oguchi ◽  
Rafael F. Castañeda Ruiz
Keyword(s):  
Electron Microscopy ◽  
Cell Wall ◽  
Key Words ◽  
Septal Wall ◽  
Apical Portion ◽  
Key Words Infection ◽  
Ultrathin Sections

Infection of nematodes by Meristacrum asterospermum and Zygnemomyces echinulatus was initiated by conidia adhering to the nematode's cuticle. Each conidium developed an infection peg to penetrate the nematode after adhesion. In M. asterospermum, an infection peg just under the penetration was found in ultrathin sections, in which the peg's cell wall was broken into several lobes that were covered entirely with an amorphous mass of electron-opaque substance. Septa formed in the apical portion of aerial conidiophore under conidiation. The septal wall was nonperforate and often contained electron-opaque inclusions. Vegetative hyphae of Z. echinulatus had typical bifurcate septa, but septa at both ends of the pedicel of conidia were often slightly deformed. Key words: infection of nematodes, Meristacrum asterospermum, septum, Zygnemomyces echinulatus.

scholarly journals The fine structure produced in cells by primary fixatives 2. Potassium dichromate

1965 ◽  
Vol s3-106 (73) ◽  
pp. 15-21
Author(s):  
JOHN R. BAKER
Keyword(s):  
Electron Microscopy ◽  
Plasma Membrane ◽  
Fine Structure ◽  
Golgi Apparatus ◽  
Nuclear Membrane ◽  
Osmium Tetroxide ◽  
Potassium Dichromate ◽  
Potassium Dichromate Solution ◽  
Zymogen Granules ◽  
Mouse Pancreas

The exocrine cells of the mouse pancreas were fixed in potassium dichromate solution, embedded in araldite or other suitable medium, and examined by electron microscopy. Almost every part of these cells is seriously distorted or destroyed by this fixative. The ergastoplasm is generally unrecognizable, the mitochondria and zymogen granules are seldom visible, and no sign of the plasma membrane, microvilli, or Golgi apparatus is seen. The contents of the nucleus are profoundly rearranged. It is seen to contain a large, dark, irregularly shaped, finely granular object; the evidence suggests that this consists of coagulated histone. The sole constituent of the cell that is well fixed is the inner nuclear membrane. The destructive properties of potassium dichromate are much mitigated when it is mixed in suitable proportions with osmium tetroxide or formaldehyde.

The fine structure of Sphaerotilus nutans

1973 ◽  
Vol 19 (3) ◽  
pp. 309-313 ◽  
Author(s):  
Judith F. M. Hoeniger ◽  
H.-D. Tauschel ◽  
J. L. Stokes
Keyword(s):  
Electron Microscopy ◽  
Plasma Membrane ◽  
Fine Structure ◽  
Lateral Position ◽  
Thin Sections ◽  
Liquid Cultures ◽  
Sphaerotilus Natans ◽  
Stationary Liquid ◽  
Basal Disk ◽  
Polar Organelle

Sphaerotilus natans developed sheathed filaments in stationary liquid cultures and motile swarm cells in shaken ones. Electron microscopy of negatively stained preparations and thin sections showed that the sheath consists of fibrils. When the filaments were grown in broth with glucose added, the sheath was much thicker and the cells were packed with granules of poly-β-hydroxybutyrate.Swarm cells possess a subpolar tuft of 10 to 30 flagella and a polar organelle which is usually inserted in a lateral position and believed to be ribbon-shaped. The polar organelle consists of an inner layer joined by spokes to an accentuated plasma membrane. The flagellar hook terminates in a basal disk, consisting of two rings, which is connected by a central rod to a second basal disk.

Ultrastructure of a marine psychrophilic Vibrio

1970 ◽  
Vol 16 (11) ◽  
pp. 1027-1031 ◽  
Author(s):  
S. F. Kennedy ◽  
R. R. Colwell ◽  
G. B. Chapman
Keyword(s):  
Electron Microscopy ◽  
Cell Wall ◽  
Plasma Membrane ◽  
Cell Division ◽  
Wall Material ◽  
Cross Wall ◽  
Growth Stages ◽  
Culture Age ◽  
Primary Mechanism ◽  
Age Studies

The structure of Vibrio marinus strain PS-207 was studied by both phase and electron microscopy. It was found to possess a trilaminar plasma membrane and cell wall. Membrane-bounded subunits containing DNA-like material were found dispersed throughout the cytoplasm. Giant round forms or "macrospheres" were observed in all growth stages. The size, shape, and construction of the "macrospheres" showed some variation, but could not be related to culture age. Studies of cell division in V. marinus strain PS-207 indicate the primary mechanism to be a synthesis and centripetal deposition of plasma membrane with a concomitant or subsequent synthesis and centripetal deposition of cross wall material.

Contractile elements of Lemna trisulca L. glycerinated cell models during chloroplast translocations

2000 ◽  
Vol 78 (4) ◽  
pp. 503-510
Author(s):  
Robert A Rinaldi ◽  
Barbara Kalisz-Nowak ◽  
Wlodzimierz Korohoda ◽  
Stanislaw Wieckowski ◽  
Wincenty Kilarski ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Cell Wall ◽  
Plasma Membrane ◽  
Contractile Element ◽  
Cell Models ◽  
Chloroplast Membranes ◽  
Chloroplast Membrane ◽  
Membrane Cell

Electron microscopy of Lemna glycerinated cell models depicts contractile elements during chloroplast translocations. One contractile element, the thin ectoplasmic layer, is [Formula: see text] 0.4 µm thick, pressed against plasma membrane-cell wall. Thin ectoplasmic layer contains numerous oriented filaments and some appear to be actin and myosin. Another contractile element is the outer chloroplast membrane which envelops each chloroplast and joins or fuses with the thin ectoplasmic layer. Choroplast interconnections are formed between two or more chloroplasts by outer chloroplast membranes; they enhance chloroplast communications, translocations, and molecular exchanges.Key words: chloroplast translocations, contractility, tubular connections.

Enlarged Crystalline Patches on the Plasma Membrane of Yeast Protoplasts

1980 ◽  
Vol 38 ◽  
pp. 686-687
Author(s):  
G. Sosinsky ◽  
R. Schekman ◽  
R. Glaeser
Keyword(s):  
Electron Microscopy ◽  
Cell Wall ◽  
Plasma Membrane ◽  
High Resolution Electron Microscopy ◽  
Yeast Cells ◽  
Physiological Conditions ◽  
Resolution Electron ◽  
Yeast Protoplasts ◽  
Intramembraneous Particles ◽  
Crystalline Array

The crystalline patches of intramembraneous particles that form in the yeast plasma membrane, under stationary state physiological conditions, represent a potentially interesting specimen for high resolution electron microscopy. Isolation of these crystalline membrane patches first requires removal of the cell wall and the formation of osmotically fragile yeast protoplasts. In developing a procedure for the isolation of these crystalline membrane patches, we have found that the intramembraneous particles form much larger crystalline patches in protoplasts than in intact yeast cells. We have performed deep etch experiments and have found that the crystalline array of particles is not expressed on the extracellular surface of the plasma membrane.

scholarly journals Electron Microscopy Studies of Cell-Wall-Anchored Cellulose (Avicel)-Binding Protein (AbpS) from Streptomyces reticuli

1999 ◽  
Vol 65 (3) ◽  
pp. 886-892 ◽  
Author(s):  
Stefan Walter ◽  
Manfred Rohde ◽  
Matthias Machner ◽  
Hildgund Schrempf
Keyword(s):  
Electron Microscopy ◽  
Cell Wall ◽  
Binding Protein ◽  
Crystalline Cellulose ◽  
Terminal Part ◽  
Transmission Electron ◽  
Hydrophobic Amino Acids ◽  
Ultrathin Sections ◽  
Covalently Linked ◽  
Scanning Electron

ABSTRACT Streptomyces reticuli produces a 35-kDa cellulose (Avicel)-binding protein (AbpS) which interacts strongly with crystalline cellulose but not with soluble types of cellulose. Antibodies that were highly specific for the NH2-terminal part of AbpS were isolated by using truncated AbpS proteins that differed in the length of the NH2 terminus. Using these antibodies for immunolabelling and investigations in which fluorescence, transmission electron, or immunofield scanning electron microscopy was used showed that the NH2 terminus of AbpS protrudes from the murein layer of S. reticuli. Additionally, inspection of ultrathin sections of the cell wall, as well as biochemical experiments performed with isolated murein, revealed that AbpS is tightly and very likely covalently linked to the polyglucane layer. As AbpS has also been found to be associated with protoplasts, we predicted that a COOH-terminal stretch consisting of 17 hydrophobic amino acids anchors the protein to the membrane. Different amounts of AbpS homologues of several Streptomyces strains were synthesized.

Preparation of Ultrathin Sections of Polymeric Materials

1963 ◽  
Vol 36 (3) ◽  
pp. 799-802
Author(s):  
K. Kh. Razikov ◽  
G. S. Markova
Keyword(s):  
Electron Microscopy ◽  
Fine Structure ◽  
Electron Diffraction ◽  
Present Article ◽  
Ultrathin Section ◽  
Polymeric Materials ◽  
Thermal Regulation ◽  
Polymeric Fibers ◽  
Thin Sections ◽  
Ultrathin Sections

Abstract Much importance attaches at the present time to the use of ultrathin sections for the investigation of the structure of polymeric materials by electron microscopy, electron diffraction and other methods. Extremely thin sections (down to hundredths of a micron) can be prepared by means of ultramicrotomes in which thermal regulation of the feed of the specimen is provided. The use of ultramicrotomes in various branches of sciences has given valuable information on the fine structure of many substances. In the present article we describe the use of the ultrathin section method for the investigation of the structure of polymers by means of an ultramicrotome of the “Sjostrand Ultra-microtome LKB-Producter” type. As a result of the elasticity of polymeric materials the preparation of thin sections is rendered difficult. Therefore the development of a method of producing ultrathin sections of polymeric materials is of considerable interest. We have developed such a method for the study of the structure of thin polymeric fibers (of diameter 15 to 20 µ) of thick monofilament (of diameter 0.5 mm and above) and also of films. The technique of preparation of ultrathin sections consists of the following stages: 1) embedding the specimens for investigation; 2) preparation of the specimen for cutting; 3) preparation of the knives; and 4) preparation of the apparatus and cutting.

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