Cytochemical localization of peroxidase activity in wound vessel members of Coleus

1972 ◽  
Vol 50 (5) ◽  
pp. 977-983 ◽  
Author(s):  
Peter K. Hepler ◽  
Rita M. Rice ◽  
William A. Terranova
Keyword(s):  
Peroxidase Activity ◽  
Cell Walls ◽  
Secondary Wall ◽  
Primary Wall ◽  
Electron Microscopic ◽  
Cytochemical Localization ◽  
Secondary Thickening ◽  
Vessel Elements ◽  
Microscopic Investigations

Peroxidase activity has been localized in the cell walls and cytoplasm of wound vessel elements of Coleus which had been fixed in glutaraldehyde, incubated in diaminobenzidine (DAB) and H2O2, and postfixed in OSO4. Electron microscopic investigations revealed prominent staining in the reticulate secondary wall and in the primary wall where the secondary thickenings attach. The stain in the secondary wall is finely textured and heavier towards its periphery than towards its core. The staining of the primary wall, however, is coarsely granular. In the cytoplasm of differentiating vessel elements electron-opaque deposits are observed in the plasmalemma, especially where it overlies the secondary thickening, and in the dictyosomes and their associated vesicles. Staining also occurs on the internal membranes of developing chloroplasts where it is most likely the result of photooxidation of DAB.Staining, except in chloroplasts, appears to be due specifically to peroxidase, since either removal of H2O2 or preincubation with KCN markedly reduces staining, whereas preincubation with aminotriazole, an inhibitor of catalase, does not. The similarity of localization of peroxidase and lignin in the walls of Coleus wound vessel elements supports the postulate that the enzyme participates in lignification.

Localisation structurale et ultrastructurale d'activités peroxydasiques dans les parois du mésophylle et des fibres en cours de lignification chez l'alfa (Stipa tenacissima)

1984 ◽  
Vol 62 (12) ◽  
pp. 2644-2649 ◽  
Author(s):  
M. Harche
Keyword(s):  
Peroxidase Activity ◽  
Oxidase Activity ◽  
Cell Walls ◽  
Secondary Wall ◽  
Outer Part ◽  
Potassium Cyanide ◽  
Primary Wall ◽  
Stipa Tenacissima ◽  
Parenchyma Cells

Using diaminobenzidine as substrate, peroxidase activity was localized in the walls of parenchyma cells and differentiating fibres. In mature fibres and parenchyma a slight activity could be recognized in primary walls only. In parenchyma cells, peroxidase activity was fairly inhibited with heat, potassium cyanide, and aminotriazole, which could indicate the presence of catalase within the cell walls. However, in plasmodesmatal regions peroxidases were- resistant to the above inhibitors. Syringaldazine oxidase activity was present only in the primary wall and the outer part of the secondary wall of differentiating fibres. The parallelism between lignification and peroxidase activity in the secondary walls supports the hypothesis of the involvement of these enzymes in the lignification process.

scholarly journals Arrangement of Cellulose Microfibrils in Walls of Elongating Parenchyma Cells

1958 ◽  
Vol 4 (4) ◽  
pp. 377-382 ◽  
Author(s):  
G. Setterfield ◽  
S. T. Bayley
Keyword(s):  
Cell Walls ◽  
Secondary Wall ◽  
Cellular Differentiation ◽  
Cellulose Microfibrils ◽  
Field Region ◽  
Primary Wall ◽  
Parenchyma Cells ◽  
Pit Field ◽  
Wall Growth ◽  
Electron Microscopes

The arrangement of cellulose microfibrils in walls of elongating parenchyma cells of Avena coleoptiles, onion roots, and celery petioles was studied in polarizing and electron microscopes by examining whole cell walls and sections. Walls of these cells consist firstly of regions containing the primary pit fields and composed of microfibrils oriented predominantly transversely. The transverse microfibrils show a progressive disorientation from the inside to the outside of the wall which is consistent with the multinet model of wall growth. Between the pit-field regions and running the length of the cells are ribs composed of longitudinally oriented microfibrils. Two types of rib have been found at all stages of cell elongation. In some regions, the wall appears to consist entirely of longitudinal microfibrils so that the rib forms an integral part of the wall. At the edges of such ribs the microfibrils can be seen to change direction from longitudinal in the rib to transverse in the pit-field region. Often, however, the rib appears to consist of an extra separate layer of longitudinal microfibrils outside a continuous wall of transverse microfibrils. These ribs are quite distinct from secondary wall, which consists of longitudinal microfibrils deposited within the primary wall after elongation has ceased. It is evident that the arrangement of cellulose microfibrils in a primary wall can be complex and is probably an expression of specific cellular differentiation.

scholarly journals Cytochemical localization of peroxidase activity in early developmental stages of the moss Ceratodon purpureus. Light-microscopic observations

2015 ◽  
Vol 48 (2) ◽  
pp. 171-177
Author(s):  
B. Politycka ◽  
F. Młodzianowski ◽  
A. Woźny
Keyword(s):  
Peroxidase Activity ◽  
Cell Walls ◽  
Developmental Stages ◽  
Cytochemical Localization ◽  
Ceratodon Purpureus ◽  
Early Developmental Stages ◽  
Early Developmental

Peroxidase activity was localized in the cell walls and minute cytoplasm granules of swollen and germinating spores and in the several-celled protonema of the moss <i>Ceratodon purpureus</i> kept in darkness. Kinetin in a concentration of 100 μM inhibited the protonema development and also depressed the activity of this enzyme.

Relationship of autofluorescent and ultraviolet-absorbing components in cell walls and wall appositions to disease resistance in kohlrabi roots

1986 ◽  
Vol 64 (2) ◽  
pp. 273-275 ◽  
Author(s):  
James R. Aist ◽  
Herbert W. Israel
Keyword(s):  
Cell Walls ◽  
Secondary Wall ◽  
Root Hairs ◽  
Root Hair Cell ◽  
Vessel Elements ◽  
Wall Appositions ◽  
Olpidium Brassicae ◽  
Phenolic Derivatives ◽  
Relationship Of ◽  
Resistance To Penetration

It has been shown that wound plugs induced mechanically by bending of kohlrabi root hairs are more resistant to subsequent penetration attempts by Olpidium brassicae than are papillae induced by the fungus. A histochemical, autofluorescence, and ultraviolet-microspectrophotometric study was undertaken to determine if a differential composition of phenolic derivatives could explain this difference in resistance. Phenolics in the secondary wall thickenings of xylem vessel elements of roots were distinct from those in wound plugs, papillae, and root hair cell walls. But phenolics in wound plugs and papillae could not be distinguished from each other by the methods employed. Thus, the results do not support the hypothesis that wound plugs are more resistant to penetration than are papillae because they contain phenolic derivatives not found in the latter. However, the possibility that an earlier deposition of phenolics in wound plugs accounts for their greater resistance to penetration has not been ruled out.

ON THE CELL WALLS OF DIMORPHIC FUNGI CAUSING SYSTEMIC INFECTIONS

1954 ◽  
Vol 1 (1) ◽  
pp. 1-5 ◽  
Author(s):  
F. Blank
Keyword(s):  
Cell Walls ◽  
Histoplasma Capsulatum ◽  
Paracoccidioides Brasiliensis ◽  
Blastomyces Dermatitidis ◽  
Growth Phases ◽  
Electron Microscopic ◽  
Dimorphic Fungi ◽  
Polymeric Substance ◽  
Systemic Infections ◽  
Microscopic Investigations

Cultures of the mycelial and tissue-like growth phases of Blastomyces dermatitidis, Paracoccidioides brasiliensis, Histoplasma capsulatum, and Sporotrichum Schenckii were extracted and oxidized as described by Scholl in 1908. Debye–Scherrer diagrams of the so prepared cell walls show the presence of chitin in both growth phases of each fungus investigated, and give no evidence of the presence of cellulose or another high polymeric substance in the membranes. Nitrogen determinations of the same material corroborate these findings. Electron-microscopic investigations of the isolated chitin of Blastomyces dermatitidis did not reveal any substantial difference in the submicroscopic structures of the framework of the mycelial and yeast-like growth phases.

scholarly journals Cytochemical localization of peroxidase activity in the protonema of the moss Ceratodon purpureus during differentiation of gametophore buds induced by kinetin

2015 ◽  
Vol 45 (1–2) ◽  
pp. 119-125
Author(s):  
A. Sobkowiak ◽  
F. Młodzianowski ◽  
A. Szweykowska
Keyword(s):  
High Activity ◽  
Peroxidase Activity ◽  
Cell Walls ◽  
Differentiation Process ◽  
Colour Reaction ◽  
Cytochemical Localization ◽  
Ceratodon Purpureus ◽  
Reaction Characteristic

An increase in the activity of peroxidases under the influence of kinetin has been demonstrated in the protonema of the moss <i>Ceratodon purpureus</i>. It was connected above all with initiation and acceleration of the differentiation process of gametophore buds which showed a high activity of these enzymes. The increase in peroxidase activity was also noted in the degenerating intercalary cells which produced the buds. The colour reaction characteristic for peroxidases was best noticeable in the minute spherical granules (peroxysomes), nucleoli and cell walls.

A Correlation between Detergent Tolerance and Cell Wall Structure in Green Algae

1987 ◽  
Vol 42 (3) ◽  
pp. 245-250 ◽  
Author(s):  
Susanne Biedlingmaier ◽  
Gerhard Wanner ◽  
Ahlert Schmidt
Keyword(s):  
Cell Wall ◽  
Chlorophyll Content ◽  
Cell Walls ◽  
Linear Alkylbenzene Sulfonate ◽  
Wall Structure ◽  
Electron Microscopic ◽  
Linear Alkylbenzene ◽  
Chemical Attack ◽  
Alkylbenzene Sulfonate ◽  
Microscopic Investigations

12 strains of the geni Chlorella, Scenedesmus, Chlamydomonas, and Dunaliella were tested for their tolerance against the anionic detergent “LAS” (linear alkylbenzene sulfonate). Cellular parameters (cell titer and chlorophyll content) were monitored for 28 days after addition of LAS (0.01-2 mᴍ). A 100-fold difference in sensitivity toward LAS was detected for the algal strains analyzed. Electron microscopic investigations revealed that LAS-resistance is correlated with both, the presence of thick cell walls and sporopollenin layers. It is speculated that this structure acts as a protecting coat preventing the chemical attack of detergents on algal cells. An application for selecting algae by detergents is proposed.

Autofluorescent and ultraviolet-absorbing components in cell walls and papillae of barley coleoptiles and their relationship to disease resistance

1986 ◽  
Vol 64 (2) ◽  
pp. 266-272 ◽  
Author(s):  
James R. Aist ◽  
Herbert W. Israel
Keyword(s):  
Disease Resistance ◽  
Cell Walls ◽  
Secondary Wall ◽  
Epidermal Cells ◽  
Ultraviolet Absorption ◽  
Absorption Properties ◽  
Vessel Elements ◽  
Histochemical Tests ◽  
Phenolic Derivatives ◽  
Periclinal Walls

Earlier studies showed that normal-size papillae induced in barley coleoptile epidermal cells by Erysiphe graminis f. sp. hordei were less effective in resisting fungal penetration attempts than were oversize papillae. To determine if a differential content of phenolic derivatives could account for this difference in resistance, we analyzed normal papillae and oversize papillae by histochemical, epifluorimetric, and ultraviolet-microspectrophotometric methods. Whereas the histochemical tests revealed phenolic derivatives only in oversize papillae, the autofluorescence and ultraviolet-absorption properties indicated that both types of papillae contain phenolics. Ultraviolet-absorption spectra indicated that the phenolics were primarily phenylpropanoid groups. Phenolics in papillae were distinct from both those in the secondary wall thickenings of coleoptile xylem vessel elements and those in the periclinal walls of coleoptile epidermal cells. The deposition of phenolics in oversize papillae long before they were challenged by the fungus, the presence of certain phenolics that, tentatively, were detected histochemically only in the oversize papillae, or both could have rendered them resistant to penetration by the fungus.

Convergent Beam Electron Diffraction

1978 ◽  
Vol 36 (3) ◽  
pp. 304-315
Author(s):  
G. Lehmpfuhl
Keyword(s):  
Electron Diffraction ◽  
Diffraction Pattern ◽  
Crystal Surface ◽  
Diffraction Spot ◽  
Crystal Thickness ◽  
Large Area ◽  
Electron Microscopic ◽  
Additional Information ◽  
Microscopic Investigations

Introduction In electron microscopic investigations of crystalline specimens the direct observation of the electron diffraction pattern gives additional information about the specimen. The quality of this information depends on the quality of the crystals or the crystal area contributing to the diffraction pattern. By selected area diffraction in a conventional electron microscope, specimen areas as small as 1 µ in diameter can be investigated. It is well known that crystal areas of that size which must be thin enough (in the order of 1000 Å) for electron microscopic investigations are normally somewhat distorted by bending, or they are not homogeneous. Furthermore, the crystal surface is not well defined over such a large area. These are facts which cause reduction of information in the diffraction pattern. The intensity of a diffraction spot, for example, depends on the crystal thickness. If the thickness is not uniform over the investigated area, one observes an averaged intensity, so that the intensity distribution in the diffraction pattern cannot be used for an analysis unless additional information is available.

Determination of the phase structure of polymerblends by electron microscopy

1978 ◽  
Vol 36 (1) ◽  
pp. 492-493
Author(s):  
Dr. G. Kaemof
Keyword(s):  
Screw Extruder ◽  
Electron Microscopic ◽  
Thin Sections ◽  
Single Screw Extruder ◽  
Transmission Electron ◽  
The Matrix ◽  
Twin Screw ◽  
Special Case ◽  
Microscopic Investigations

A mixture of polycarbonate (PC) and styrene-acrylonitrile-copolymer (SAN) represents a very good example for the efficiency of electron microscopic investigations concerning the determination of optimum production procedures for high grade product properties.The following parameters have been varied:components of charge (PC : SAN 50 : 50, 60 : 40, 70 : 30), kind of compounding machine (single screw extruder, twin screw extruder, discontinuous kneader), mass-temperature (lowest and highest possible temperature).The transmission electron microscopic investigations (TEM) were carried out on ultra thin sections, the PC-phase of which was selectively etched by triethylamine.The phase transition (matrix to disperse phase) does not occur - as might be expected - at a PC to SAN ratio of 50 : 50, but at a ratio of 65 : 35. Our results show that the matrix is preferably formed by the components with the lower melting viscosity (in this special case SAN), even at concentrations of less than 50 %.

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