scholarly journals THE INTRACELLULAR LOCALIZATION OF INORGANIC CATIONS WITH POTASSIUM PYROANTIMONATE

1970 ◽  
Vol 45 (2) ◽  
pp. 355-366 ◽  
Author(s):  
Carlos J. Tandler ◽  
César M. Libanati ◽  
Carlos A. Sanchis
Keyword(s):  
Cell Morphology ◽  
Intact Cell ◽  
Intracellular Localization ◽  
Bound State ◽  
Plant Tissues ◽  
Inorganic Cations ◽  
Large Pool ◽  
Inorganic Cation ◽  
Calcium Magnesium ◽  
Potassium Pyroantimonate

Potassium pyroantimonate, when used as fixative (saturated or half-saturated, without addition of any conventional fixative) has been demonstrated to produce intracellular precipitates of the insoluble salts of calcium, magnesium, and sodium and to preserve the general cell morphology. In both animal and plant tissues, the electron-opaque antimonate precipitates were found deposited in the nucleus—as well as within the nucleolus—and in the cytoplasm, largely at the site of the ribonucleoprotein particles; the condensed chromatin appeared relatively free of precipitates. The inorganic cations are probably in a loosely bound state since they are not retained by conventional fixatives. The implications of this inorganic cation distribution in the intact cell are discussed in connection with their anionic counterparts, i.e., complexing of cations by fixed anionic charges and the coexistence of a large pool of inorganic orthophosphate anions in the nucleus and nucleolus.

scholarly journals THE DISTRIBUTION OF INORGANIC CATIONS IN MOUSE TESTIS

1971 ◽  
Vol 48 (2) ◽  
pp. 314-323 ◽  
Author(s):  
Abraham L. Kierszenbaum ◽  
Cesar M. Libanati ◽  
Carlos J. Tandler
Keyword(s):  
Aqueous Solution ◽  
Connective Tissue ◽  
Cell Morphology ◽  
Seminiferous Tubules ◽  
Plant Tissues ◽  
Cell Nuclei ◽  
Double Line ◽  
Inorganic Cations ◽  
Inorganic Cation ◽  
Potassium Pyroantimonate

For localization of pyroantimonate-precipitable cations, mouse testes were fixed with a saturated aqueous solution of potassium pyroantimonate (pH about 9.2, without addition of any conventional fixative), hardened with formaldehyde, and postosmicated. A good preservation of the cell membranes and over-all cell morphology is obtained as well as a consistent and reproducible localization of the insoluble antimonate salts of magnesium, calcium, and sodium. Four sites of prominent antimonate deposits are revealed, besides a more or less uniform distribution of the precipitates. These sites are: (a) In the walls of the seminiferous tubules, localized in two concentric layers corresponding to the inner and outer layers of the tubular wall; (b) Around the blood vessels and adjacent connective tissue; (c) At the area of contact between the Sertoli cell and spermatids, where a double line of precipitate surrounds the head of the mature spermatids; and (d) In the cell nuclei, disposed between regions of the condensed chromatin. The nucleus of mature spermatids did not show any sign of antimonate precipitation. The implications of this inorganic cation distribution are discussed with relation to their anionic counterparts, their localization in other animal and plant tissues, and the possibility that those sites may represent barriers to the free passage of ions.

scholarly journals INORGANIC CATIONS IN THE CELL NUCLEUS

1972 ◽  
Vol 53 (2) ◽  
pp. 483-493 ◽  
Author(s):  
Laura L. Tres ◽  
A. L. Kierszenbaum ◽  
C. J. Tandler
Keyword(s):  
Meiotic Prophase ◽  
Rna Synthesis ◽  
Adult Mouse ◽  
Divalent Cations ◽  
Synthetic Activity ◽  
Inorganic Cations ◽  
Transcription Process ◽  
Inorganic Cation ◽  
Interchromatin Granules ◽  
Potassium Pyroantimonate

Earlier reports indicated the presence of significant amounts of inorganic salts in the nucleus. In the present study the possibility that this might be related to the transcription process was tested on seminiferous epithelium of the adult mouse, using potassium pyroantimonate as a fixative. The results indicated that a correlation exists between the inorganic cations comprising the pyroantimonate-precipitable fraction and the RNA synthetic activity. During meiotic prophase an accumulation of cation-antimonate precipitates occurs dispersed through the middle pachytene nuclei, the stage in which RNA synthesis reaches a maximum. At other stages (zygotene to diplotene), where RNA synthesis falls to a low level, that pattern is not seen; cation-antimonate deposits are restricted to a few masses in areas apparently free of chromatin. The condensed sex chromosomes, the heterochromatin of the "basal knobs," the axial elements, and the synaptonemal complexes are devoid of antimonate deposits during the meiotic prophase. The Sertoli cells, active in RNA synthesis in both nucleoplasm and nucleolus, show cation-antimonate deposits at these sites. In the nucleoplasm some "patches" of precipitates appear coincident with clusters of interchromatin granules; in the nucleolus the inorganic cations are mainly located in the fibrillar and/or amorphous areas, whereas relatively few are shown by the granular component. The condensed chromatin bodies associated with the nucleolus were always free of antimonate precipitates. It is suggested that the observed sites of inorganic cation accumulation within the nucleus may at least partially indicate the presence of RNA polymerases, the activity of which is dependent on divalent cations.

scholarly journals INORGANIC CATIONS IN RAT KIDNEY

1971 ◽  
Vol 50 (3) ◽  
pp. 830-839 ◽  
Author(s):  
C. J. Tandler ◽  
A. L. Kierszenbaum
Keyword(s):  
Aqueous Solution ◽  
Connective Tissue ◽  
Rat Kidney ◽  
Basement Membranes ◽  
Cell Nuclei ◽  
Inorganic Cations ◽  
Dense Granules ◽  
Distal Tubules ◽  
The Masses ◽  
Potassium Pyroantimonate

For localization of pyroantimonate-precipitable cations, rat kidney was fixed by perfusion with a saturated aqueous solution of potassium pyroantimonate (pH about 9.2, without addition of any conventional fixative). A remarkably good preservation of the tissue and cell morphology was obtained as well as a consistent and reproducible localization of the insoluble antimonate salts of magnesium, calcium, and sodium. All proximal and distal tubules and glomeruli were delimited by massive electron-opaque precipitates localized in the basement membrane and, to a lesser extent, in adjacent connective tissue. In the intraglomerular capillaries the antimonate precipitate was encountered in the basement membranes and also between the foot processes. In addition to a more or less uniform distribution in the cytoplasm and between the microvilli of the brush border, antimonate precipitates were found in all cell nuclei, mainly between the masses of condensed chromatin. The mitochondria usually contained a few large antimonate deposits which probably correspond to the so-called "dense granules" observed after conventional fixations.

OCCURRENCE AND PROPERTIES OF L-AMINOACID:2-GLYOXYLATE AMINOTRANSFERASE IN PLANTS

1965 ◽  
Vol 43 (4) ◽  
pp. 495-506 ◽  
Author(s):  
E. A. Cossins ◽  
S. K. Sinha
Keyword(s):  
Enzyme System ◽  
Intracellular Localization ◽  
Plant Tissues ◽  
Amino Group ◽  
Transaminase Activity ◽  
Higher Plant ◽  
Amino Donor ◽  
Glyoxylate Aminotransferase

Extracts prepared from a variety of higher plant tissues have been examined for L-aminoacid:2-glyoxylate aminotransferase (glyoxylate transaminase) activity. This enzyme has been detected in extracts prepared from sunflower cotyledons, corn coleoptiles, mature pea leaves, and carrot storage tissues.Measurement of glyoxylate transaminase activity was based on ability of the extracts to convert glyoxylate- 1,2-C14 to glycine-1,2-C14 in the presence of a suitable amino group donor.Properties of this enzyme system, including amino donor requirements, inhibition, pH optima, and reversibility, have been studied using extracts prepared from mature pea leaves. In sunflower cotyledons, glyoxylate transaminase activity decreased during germination. Studies of the intracellular localization of this enzyme have shown that glyoxylate transamination occurs mainly in the cytoplasm.

Potassium nutrition, ionic relations, and oxalic acid accumulation in three cultivars of Setaria sphacelata

1972 ◽  
Vol 23 (6) ◽  
pp. 969 ◽  
Author(s):  
FW Smith
Keyword(s):  
Oxalic Acid ◽  
Nitrogen Fertilization ◽  
Response Curves ◽  
Potassium Nutrition ◽  
Potassium Fertilization ◽  
Inorganic Cation ◽  
Setaria Sphacelata ◽  
Calcium Magnesium ◽  
Ionic Relations ◽  
Potassium Response

The effects of potassium and nitrogen fertilization on growth, chemical composition, ionic relations, and oxalic acid levels in the Nandi, Kazungula, and Narok cultivars of Setaria sphacelata have been studied. Potassium response curves have been derived and their use in predicting 'critical potassium levels' in these grasses discussed. Cation-anion balances (total inorganic cation concentrationndash;total inorganic anion concentration) have been calculated and the effects of potassium and nitrogen fertilization on ionic relations are discussed. The Kazungula and Narok cultivars contained higher levels of the cations calcium, magnesium, sodium, and ammonium when grown under limiting potassium conditions than when supplied with adequate potassium. The Nandi cultivar was similarly affected but did not accumulate sodium. All plants with high levels of potassium in their tissues also contained high levels of nitrate when the nitrogen supply was adequate. The cation-anion balance increased with increasing potassium fertilization in all cultivars but there was an interaction between potassium fertilization and nitrogen fertilization. Potassium and nitrogen fertilization resulted in large increases in oxalic acid levels. It is shown that the amount of oxalic acid accumulated is related to the cation-anion balance.

scholarly journals OspE2 of Shigella sonnei Is Required for the Maintenance of Cell Architecture of Bacterium-Infected Cells

2006 ◽  
Vol 74 (5) ◽  
pp. 2587-2595 ◽  
Author(s):  
Masashi Miura ◽  
Jun Terajima ◽  
Hidemasa Izumiya ◽  
Jiro Mitobe ◽  
Teruya Komano ◽  
...  
Keyword(s):  
Cell Morphology ◽  
Deletion Mutant ◽  
Intact Cell ◽  
Shigella Sonnei ◽  
Host Cells ◽  
Cell Monolayers ◽  
Bacterial Transmission ◽  
Infected Cells ◽  
Invasion Analysis ◽  
In Cells

ABSTRACT The OspE2 product of Shigella spp., the expression of which is regulated by the mxiE gene, is secreted through a type III secretion system into host cells. We investigated the function of OspE2 of Shigella sonnei by using cultured epithelial cells. Cells invaded by an ospE2 deletion mutant altered their morphology into the rounding shape, which was not due to cell death, whereas cells invaded by the wild-type strain kept their cell shape intact. The ospE2 mutation did not affect initial cell entry and multiplication in cells, but the mutant formed smaller-than-normal plaques on cell monolayers, indicating a deficiency in cell-to-cell spread by the bacteria. An mxiE deletion mutant also showed changes in cell morphology and deficiency in bacterial spread to adjacent cells. In cells invaded by the ospE2 mutant, disturbance of actin stress fibers was prominent at 3 h after invasion. Analysis of OspE2 localization indicated that the OspE2 protein accumulated on focal contact-like structures in the infected host cells. These results suggest that colocalization of the OspE2 protein in the focal contacts of infected cells may function to maintain an intact cell morphology. The morphological change induced by invasion of the ospE2 mutant may affect secondary bacterial transmission.

scholarly journals An automated method for the determination of deoxyribonuclease activity as exemplified by fractionation of the components of the medicament Varidase®

1993 ◽  
Vol 15 (2) ◽  
pp. 65-70 ◽  
Author(s):  
I. C. Locke ◽  
M. P. Ramsey ◽  
S. S. Hill ◽  
B. G. Carpenter
Keyword(s):  
Exchange Resin ◽  
Active Constituents ◽  
Inorganic Cations ◽  
Automated Method ◽  
Absorbance Change ◽  
Inorganic Cation ◽  
Anionic Exchange ◽  
Salt Gradient ◽  
Deoxyribonuclease Activity

The activity of most deoxyribonuclease enzymes can be monitored by measuring the change in absorbance at 260 nm which accompanies the breakdown of the double-stranded structure of native DNA. An automated method for determining deoxyribonuclease activity, based on such an absorbance change, which can overcome problems of inhibition arising from the presence of inorganic cations, is described. Variations in inorganic cation concentration is a particular problem when measuring the activity of chromatographic fractions eluted via a salt gradient. A comparison is made between the automated and a manual method for the assay of deoxyribonuclease active constituents, of the medicament ‘Varidase’, eluted from a Cellex-D (Bio-Rad Laboratories Ltd) anionic exchange resin using a 0.05-1.0 M sodium chloride gradient.

POTASSIUM IN PLANT METABOLISM.: II. EFFECT OF POTASSIUM UPON THE CARBOHYDRATE AND MINERAL COMPOSITION OF POTATO PLANTS

1959 ◽  
Vol 39 (2) ◽  
pp. 246-252 ◽  
Author(s):  
G. M. Ward
Keyword(s):  
Vegetative Growth ◽  
Starch Content ◽  
Sand Culture ◽  
Plant Tissues ◽  
Plant Metabolism ◽  
Direct Function ◽  
Potato Plants ◽  
Sodium Calcium ◽  
Calcium Magnesium ◽  
Potassium Application

Potato plants grown in sand culture and fed varying quantities of potassium responded with more vegetative growth and produced more and larger tubers as potassium application increased. Seven treatments ranging from complete deficiency to luxury consumption levels resulted in increasing amounts of potassium in all plant tissues and in decreasing amounts of sodium, calcium, magnesium, iron and copper in certain tissues. The amount of starch in the leaves was a direct function of the amount of potassium applied, but the starch content of the tubers was not.

Levels of small molecules in dormant spores of Sporosarcina species and comparison with levels in spores of Bacillus and Clostridium species

1993 ◽  
Vol 39 (2) ◽  
pp. 259-262 ◽  
Author(s):  
Charles A. Loshon ◽  
Peter Setlow
Keyword(s):  
Amino Acids ◽  
Small Molecules ◽  
Free Amino ◽  
Evolutionary Relationship ◽  
Bacillus Species ◽  
Clostridium Species ◽  
Inorganic Cations ◽  
Large Pool ◽  
Sporulation Process ◽  
Phosphoglyceric Acid

Dormant spores of Sporosarcina halophila and Sporosarcina ureae contained no detectable ATP, significant levels of ADP, even higher levels of AMP, and a large pool of 3-phosphoglyceric acid, similar to what is found in dormant spores of Bacillus and Clostridium species. Sporosarcina halophila and S. ureae spores also contained significant pools of free amino acids, in particular glutamic acid, as in the case with spores of Bacillus but not Clostridium species. Levels of monovalent and divalent inorganic cations were comparable in spores of Sporosarcina, Clostridium, and Bacillus species, and cation levels in spores of the slight halophile S. halophila were similar to those in S. ureae spores. These data suggest that levels of small molecules are generally similar in spores of all Gram-positive organisms, and further suggest that these levels reflect fundamental and conserved features of the sporulation process and dormant spores in these organisms. The data are also consistent with the proposed close evolutionary relationship between Bacillus and Sporosarcina species.Key words: Bacillus, Clostridium, small molecules, spores, Sporosarcina.

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