EDTA Treatments Research Articles

Ischemia induces a reduction in the content of ulinastatin-like substance in the murine hippocampus.

Effects of ischemia on the content of a ulinastatin (UT)-like substance in the murine cerebral cortex and hippocampus were studied. At 24 h post-ischemia, a significant (p < 0.05) decrease in the content of UT-like substance in the hippocampus but not the cerebral cortex and a concurrent increase in the activity of micro-calpain were observed. In in vitro experiments, a decrease was registered in the content of UT-like substance in the hippocampus in the presence of calcium. This decrease was inhibited by both EDTA and calpastatin treatments. These results implicate the destruction of UT-like substance by micro-calpain in the ischemic hippocampus.

Effect of strontium on chlorophyll content, peroxidase activity, and iron distribution in cell walls

An investigation was conducted to investigate the effect of strontium on peroxidase (POD) activity and chlorophyll (Chl) degradation in sugar beets (Beta vulgaris). Peroxidase activity was considerably increased by 10 mM strontium (Sr) addition to a Hoagland nutrient solution without additional application of calcium (Ca). When grown in a Hoagland nutrient solution containing both 5 mM Ca and 5 mM Sr, POD activity in all leaves and roots decreased, whereas Chl content per g fresh weight (f.w.) was increased slightly compared to POD activity and Chl contents in plants treated with calcium alone. Chla/b ratios were also affected by Sr treatment. Both Sr and Ca contents were higher in older leaves than in younger leaves. Cation spectra obtained by a laser microprobe mass analyzer indicated that the intensity of sodium (Na) and potassium (K) peaks were greatly reduced by EDTA and EGTA treatments, but those of Ca, Sr, and magnesium (Mg) peaks were not.

EDTA suppresses the growth of oceanic phytoplankton from the Northeast Subarctic Pacific

The effect of EDTA on the growth and biochemical composition of two oceanic phytoplankton isolates from the Northeast Subarctic Pacific was examined. Free metal ion concentrations were kept similar for all EDTA treatments (1, 10, 100 μM EDTA), and were present in replete amounts. In both the oceanic coccolithophore and the oceanic diatom, 100 μM EDTA inhibited cell division, causing a >50% and a 30% decrease in maximum growth for the coccolithophore and diatom, respectively. Cell volume, chlorophyll a and nitrogen quotas were not affected by EDTA concentrations, but carbon quotas were, with EDTA concentrations of 100 μM causing a significant increase in cellular carbon for the diatom, and coccolith carbon for the coccolithophore. The observed detrimental effects of EDTA on cell division may help explain why oceanic species have been difficult to culture. Caution is warranted when large concentrations of EDTA are used in laboratory studies, especially when working with newly isolated oceanic species.

Effect of EDTA and low calcium fertility on pericarp cation levels and ripening of rin tomato fruit

Ripening inhibited ( rin ) tomato plants were grown in silicate sand and watered with half-strength Hoagland's solution until flowering. After flowering, plants were watered until run-off daily with full-strength Hoagland's solution containing 5 mM (control) or 1 mM calcium, or full-strength Hoagland's solution with 1.25 mM or 2.5 mM Na 2 EDTA. Fruit pericarp calcium levels were the same in Na 2 EDTA and control treatments at 90 days postpollination. The 1 mM Ca treatment significantly decreased total pericarp Ca levels compared to the control treatment. Sodium levels were higher in fruit from Na 2 EDTA-treated plants than controls. Fruit from control and 1 mM Ca treatments had significantly higher Zn than fruit from the Na 2 EDTA-treatments. None of the treatments induced increased ethylene production, redness, or increased soluble solids content of rin fruit.

Influence of different chemical treatments on transport of Alcaligenes paradoxus in porous media

Seven chemicals, three buffers, and a salt solution known to affect bacterial attachment were tested to quantify their abilities to enhance the penetration of Alcaligenes paradoxus in porous media. Chemical treatments included Tween 20 (a nonionic surfactant that affects hydrophobic interactions), sodium dodecyl sulfate (an anionic surfactant), EDTA (a cell membrane permeabilizer that removes outer membrane lipopolysaccharides), sodium PPi (a surface charge modifier), sodium periodate (an oxidizer that cleaves surface polysaccharides), lysozyme (an enzyme that cleaves cell wall components), and proteinase K (a nonspecific protease that cleaves peptide bonds). Buffers included MOPS [3-(N-morpholino)propanesulfonic acid], Tris, phosphate, and an unbuffered solution containing only NaCl. Transport characteristics in the porous media were compared by using a sticking coefficient, alpha, defined as the rate at which particles stick to a grain of medium divided by the rate at which they strike the grain. Tween 20 reduced alpha by 2.5 orders of magnitude, to alpha = 0.0016, and was the most effective chemical treatment for decreasing bacterial attachment to glass beads in buffered solutions. Similar reductions in alpha were achieved in unbuffered solutions by reducing the solution ionic strength to 0.01 mM. EDTA, protease, and other treatments designed to alter cell structures did not reduce alpha by more than an order of magnitude. The number of bacteria retained by the porous media was decreased by treatments that made A. paradoxus more hydrophobic and less electrostatically charged, although alpha was poorly correlated with electrophoretic mobility and hydrophobicity index measurements at lower alpha values.(ABSTRACT TRUNCATED AT 250 WORDS)

Control of the bioavailability of iron in heavy veal production by different feeding management systems: Use of Ca–EDTA as an iron chelating agent

Seventy male dairy black and white veal calves were allotted to five treatment groups: MILK, in which animals received exclusively milk replacer; MIX, in which animals received concentrates ad lib and milk replacer during the whole period, more specifically, 750 g of milk powder d−1 starting at week 4; GRAIN, in which animals received milk replacer during the first 4 wk and concentrates during the whole period; MIX+EDTA and GRAIN+EDTA, in which animals received the same diet as their respective controls plus 15 mg of EDTA mg−1 of Fe in the concentrates of the diet starting at week 4 of the experiment. MILK–fed calves had better average daily gains (ADG) than MIX–EDTA–fed or GRAIN+EDTA–fed calves (P &lt; 0.001). However, GRAIN+EDTA–fed calves had lower ADG than GRAIN calves (P &lt; 0.01). The EDTA treatments were without effect (P &gt; 0.10) on feed efficiency and EDTA did not affect N digestibility (P &gt; 0.10) or Fe retention (P &gt; 0.10). Treatments with EDTA lightened the color of the meat (P &lt; 0.01), reduced myoglobin and reduced muscle Fe (P &lt; 0.01). Diet reduced carcass fatness in the following decreasing order: MILK, MIX, GRAIN. Treatments with EDTA had no effect on carcass composition. Key words: Veal, milk-replacer, grain, meat color, chelator

Separation of casein hydrolysates using polysulfone ultrafiltration membranes with pH and EDTA treatments applied

Separation d'hydrolysats caseiques sur des membranes d'ultrafiltration en polysulfone avec variation de pH et addition de EDTA. La preparation de fractions peptidiques issues d'un hydrolysat caseique peut etre realisee par ultrafiltration afin de separer l'enzyme du melange reactionnel et/ou pour l'obtention de fractions peptidiques specifiques. Toutefois, l'ultrafiltration d'hydrolysats caseiques conduit a des phenomenes d'encrassement severes affectant a la fois la chute du flux de permeation et les proprietes de rejet de la membrane. Les membranes de polysulfone utilisees lors de travaux anterieurs presentaient des proprietes de rejet specifiques face aux acides amines charges ou hydroxyles. Pour cette etude, des membranes planes de polysulfone et de polyethersulfone ont ete selectionnees pour leurs proprietes de surface distinctes. L'ultrafiltration d'un hydrolysat trypsique de caseinate de sodium a ete etudiee et des variables physico-chimiques ont ete introduites, soient le pH de l'hydrolysat (pH 6, 8, 10) et l'ajout d'un agent sequestrant pour le calcium (20 mmol l -1 EDTA). L'evolution du flux de permeation, le coefficient de rejet de l'azote total, le profil de masse moleculaire et la composition en acides amines dans les permeats ont ete determines. Bien que les membranes de polyethersulfone possedaient une permeabilite a l'eau a 25°C superieure au polysulfone (+15%), des flux de permeation (1 h -1 m -2 ) similaires ont ete observes lors de l'ultrafiltration des hydrolysats. Les coefficients de rejet etaient similaires pour les deux materiaux. Il a ete observe que le pH et l'exces de EDTA exercaient un effet superieur a celui du materiau sur les proprietes de rejet (azote, peptides, acides amines) et sur la chute du flux de permeation. Les deux materiaux montrent un comportement different face aux molecules chargees.

Analysis of the Physical and Functional Characteristics of Cell Clumping in Lactose-Positive Transconjugants of Lactococcus lactis ssp. lactis ML3

Transconjugants of Lactococcus lactis ssp. lactis ML3 that acquire the ability to utilize lactose often exhibit self-aggregation and become able to transfer the ability to utilize lactose at frequencies 102 to 105 times higher than strain ML3. Our laboratory investigated the physical and functional characteristics of cell aggregation in ML3 transconjugants. Results showed that donor cell auto-aggregation was dissociated when cells were suspended in buffers that contained EDTA or when they were briefly exposed to proteinase K or α-chymotrypsin. Conjugation studies revealed that disruption of donor cell aggregation substantially decreased the efficiency of lactose plasmid transfer. Dissociation by EDTA or proteolytic enzyme treatments was reversible, and recovery of high frequency lactose plasmid transfer ability accompanied the restoration of donor self-aggregation. Analysis of cell-surface proteins isolated from lactose-positive, aggregation-positive and from lactose-positive, aggregation-negative transconjugants of ML3 by PAGE indicated that aggregation-positive cells produced a unique protein of approximately 125 kDa. The results suggested that cell aggregation was essential for high frequency lactose plasmid transfer in ML3 transconjugants and that at least one large protein was involved in aggregation.

Induction of systemic resistance to rust in Vicia faba by phosphate and EDTA: effects of calcium

Resistance in the upper leaves of broad bean (Vicia faba) plants to infection by the rust fungus, Uromyces viciae‐fabae, was increased following treatment of the lower leaves with 10 mm potassium phosphate or 5 mm EDTA. Increasing the interval between treatment of the lower leaves and inoculation of the upper leaves had little effect on rust infection. Thus rust infection was reduced by 50 and 34% if the upper leaves were inoculated 1 day after treatment of the lower leaves with potassium phosphate or EDTA, respectively, while there was a 75% reduction in infection if the interval between treatment and inoculation was increased to 12 days. Application of calcium nitrate (10 mm) after the phosphate or EDTA treatments prevented the induction of systemic resistance. Calcium nitrate applied alone to the lower leaves had no significant effect on rust infection of the upper leaves.

Chelant enhanced passivation of carbon steel in deoxygenated alkaline aqueous solutions

AbstractThe passivation characteristics of carbon steel surfaces at 473 K in the presence of certain chelating agents such as NTA DTP A, and HEDTA are described. The relative impacts of these chelants on the passivation process are evaluated by using base metal loss, soluble and insoluble iron concentrations in the mediums SEM studies of the topography of the surface coatings, and electrochemical investigations of the protection afforded by the oxide coating. The results have been compared with the passivation behaviour obtained under simple alkaline pH (LiOH) treatment (without chelating agents) and that previously obtained in the presence of EDTA. It is found that at 473 K, the presence of these complexing agents greatly increases the base metal loss, although a lower base metal loss is observed with LiOH. but the oxide film formed is more protective than the one formed under LiOR or EDTA treatments. The morphology of the coatings formed under complexing conditions has revealed highly developed crystall...

Cytofluorometric study of lectin binding to the keratinocytes of epidermolysis bullosa simplex

Epidermolysis bullosa (EB) simplex is a congenital disease that has blister formation following minor mechanical trauma to the skin. The least amount of information concerning the pathogenesis is known in this disease. One possibility is that there are structural abnormalities in keratinocytes. In the present study, we report the binding of lectin (Ricinus communis agglutinin, Peanut agglutinin, and Soybean agglutinin) to keratinocytes using cytofluorometry. Biopsy skin specimens were taken from patients with simplex, junctional, and dystrophic forms of EB, and normal volunteers. Free keratinocytes were obtained by the treatment of EDTA and trypsin, and fractionated by centrifugation on a continuous colloidal silica (Percoll) density gradient. Fractionated basal cells were stained with biotinyl lectins and avidin-FITC, and measured by cytofluorometry. In all lectins examined, the intensity was low in the basal cells of EB simplex, as compared with normal controls. However, there were no differences among the other forms of EB and normal controls. This results suggest the presence of structural abnormalities in epidermis of EB simplex.

Occurrence and characteristics of agglutination of Vibrio cholerae by serum from the eastern oyster, Crassostrea virginica

Cell-free hemolymph (serum) of the eastern oyster, Crassostrea virginica, agglutinated Vibrio cholerae, including all O1 serovars and biovars. Seventy-nine other strains of bacteria, including 14 genera and 26 species, were not agglutinated. The A, B, and C factors of O1 antigen were not involved in agglutination. Bacterial agglutinating (BA) activity was demonstrated for oysters inhabiting different environments of the U.S. Atlantic and Gulf coasts. Oyster serum BA titers showed high individual variation. The serum component(s) involved in BA was inhibited by 80 degrees C heat, pronase, EDTA, mucin, and fetuin treatments. N-Acetylneuraminic acid (10 mg/ml) weakly inhibited BA activity. Ligands of V. cholerae were sensitive to neuraminidase and resistant to 80 degrees C and pronase. High salinities (24 and 30%) enhanced BA. Cross-adsorption tests with V. cholerae and human O+ erythrocytes indicated that BA and hemagglutinating activities may involve different serum components. These results imply that the ecology of V. cholerae in C. virginica is influenced by agglutinating activity of oyster serum.

Release of outer membrane fragments from wild-type Escherichia coli and from several E. coli lipopolysaccharide mutants by EDTA and heat shock treatments

EDTA-induced outer membrane losses from whole cells of wild-type Escherichia coli (O111:B4) and several lipopolysaccharide (LPS) mutants derived from E. coli K-12 D21 were analyzed. EDTA treatment induced losses of LPS (up to 40%), outer membrane proteins OmpA, OmpF/C, and lipoprotein, periplasmic proteins, and phosphatidylethanolamine. The extent of these releases was strain specific. Successively more EDTA was necessary to induce these losses from strains containing LPS with increasing polysaccharide chain length. An additional heat shock immediately following the EDTA treatment had no effect on LPS release, but it decreased the release of outer membrane proteins and reduced the leakage of periplasmic proteins, suggesting that the temporary increase in outer membrane "permeability" caused by Ca2+-EDTA treatment was rapidly reversed by the redistribution of outer membrane components, a process which is favored by a mild heat shock. The fact that the material released from E. coli C600 showed a constant ratio of lipoprotein, OmpA, and phosphatidylethanolamine at all EDTA concentrations tested suggests that the material is lost as specific outer membrane patches. The envelope alterations caused by EDTA did not result in cell lysis.

Fusion of small unilamellar vesicles with viable EDTA-treated Escherichia coli cells

Fusion characteristics of EDTA-treated Escherichia coli cells with small unilamellar vesicles were investigated, using a membrane fusion assay based on resonance energy transfer. Ca2+-EDTA treatments of Escherichia coli O111:B4 (wild type), E. coli C600 (rough), and E. coli D21f2 (deep rough) which permeabilize the outer membrane by inducing the release of lipopolysaccharide and outer membrane proteins resulted in fusion activity of the intact and viable bacteria with small unilamellar vesicles. No fusion activity was observed when the EDTA treatment was omitted. Fusion could be elicited at low pH and by a combination of a higher pH and Ca2+. The low-pH-induced fusion was composed of a fast and a slow reaction. The latter and the Ca2+-induced fusion could be completely inhibited by trypsin treatments of the EDTA-treated cells, which also resulted in the simultaneous disappearance of two outer membrane protein bands (50 and 58 kilodaltons) and the appearance of proteins banding at 22, 52, and 54 kilodaltons. The most efficient fusion was obtained with negatively charged liposomes composed of cardiolipin. In contrast to the Ca2+-induced fusion, fusion was observed at low pH with small unilamellar vesicles containing lipids with decreased negative charge (phosphatidylserine). Fluorescent and phase-contrast microscopy revealed that essentially all bacteria were engaged in fusion. We propose that a Ca2+-EDTA treatment of E. coli cells results in the appearance of phospholipids and the exposure of a protein(s) in the outer leaflet of the outer membrane, both of which could mediate fusion with liposomes.

Cadmium-binding protein in a cadmium-resistant strain of Saccharomyces cerevisiae

A Cd-binding protein in the Cd 2+-resistant strain 301N of Saccharomyces cerevisiae was induced by administration to 0.5 mM CdSO 4. The protein was purified by a gel-permeation and subsequent ion-exchange column chromatographies. The purified Cd-binding protein had the characteristics of metallothioneins: (1) low molecular weight (9.0 kDa), (2) high Cd content (63 μg/mg protein), (3) amino-acid composition rich in cysteine (18%), basic and acidic amino acids and free from aromatic amino acids, and (4) an absorption shoulder at near 250 nm. Acid pH or EDTA treatments abolished 250 nm absorption of the Cd-binding protein, and the formed apoprotein was capable of binding Cd 2+, Cu 2+ and Zn 2+, respectively. Heat treatment (75 °C) little affected the ultraviolet absorption or sodium dodecyl sulfate-polyacrylamide gel electrophoresis profiles of Cd-binding protein. These results suggest that metallothionein generally found in animals also occurs in Cd-adapted yeast cells and thus has a role in its Cd-resistance.

Cytofluorometric study on lectin binding of isolated guinea pig keratinocytes

Lectin binding was cytofluorometrically measured on fractionated keratinocytes of guinea pig. Free keratinocytes were obtained by treatment of EDTA and trypsin. After the treatment, they were separated into 3 fractions by centrifugation on a continuous colloidal silica (Percoll) density gradient. Cells in each fraction were stained by biotinyl lectins and avidin-FITC, and fluorescence intensity was measured by cytofluorometry. Results obtained indicate that little cell surface glycoconjugate is lost during the preparation of free keratinocytes.

Reduction of Transit Injury-Associated Black Discoloration of Fresh Peaches with EDTA Treatments

Reduction of Transit Injury-Associated Black Discoloration of Fresh Peaches with EDTA Treatments

Effects of ionic and complexed metal concentrations on plant uptake of cadmium and micronutrient metals from solution

Uptake of Cd and micronutrient metals by intact tomato plants (Lycopersicon esculentum, cv. Wisconsin-55) from solution cultures was investigated by establishing four levels of Cd-ion activity in the presence or absence of a metal-complexing agent (±EDTA). Activity ratios of Cd, Cu, Mn, Ni, and Zn were controlled with chelating resin while activity ratios of K, Ca, and Mg were controlled with a strong-acid cation-exchange resin. Hydrogen ion activity was controlled with a weak-acid cation-exchange resin and P activity by a cation-exchange resin containing adsorbed polynuclear hydroxy-Al. The concentrations of all nutrients and Cd were maintained at concentrations similar to those occuring in solutions of sludge-amended soils. The EDTA treatments increased the concentrations of Cu and Ni in hydroponic solution by approximately four orders of magnitude, Zn by two orders of magnitude, Cd by a factor of 50, Mn by a factor of 2.4, and Fe by a factor of 1.6 Neither the Cd nor the EDTA treatments affected plant yield, and Cd treatments did not significantly affect uptake of other elements. EDTA treatments inhibited Fe uptake, enhanced Cu uptake, and had little effect on the uptake of Cd, Zn, and Mn. Accumulation of Cd, Zn, Mn, and Cu in plant shoots appears to be related to their respective ionic activities rather than their concentrations in hydroponic solution.

Localization of Rh1(D), 2(C), 3(E), 4(c), 5(e) and 25(LW) antigens of human Rh blood groups in fetal erythrocyte membranes

1. 1. The fetal erythrocyte membranes were partially solubilized with Triton X-100 at the low concentration (0.5%). The localizations of Rh1(D), 2(C), 3(E), 4(c), 5(e) and 25(LW) were investigated. 2. 2. Using hemagglutination inhibition assay, Rh1(D) antigen activity was observed in the Triton-treated membrane (Triton shell) containing mainly band 1, 2 (spectrin), band 5 (actin), band 4.1 and a part of band 3, while Rh2(C), 3(E), 4(c), 5(e) and 25(LW) antigens were detected in the supernatant containing band 3, 6, 2.2, 2.3 and 4.2. 3. 3. It is suggested that: (i) Rh1(D) antigen would associate with cytoskeleton matrix of fetal erythrocyte membranes; (ii) Rh1(D) and Rh25(LW) antigens might be integral membrane proteins, while Rh2(C), 3(E), 4(c) and 5(e) antigens would be surface membrane proteins which are easily released from membranes by EDTA, mercaptoethanol and alkaline treatments.

Comparison of immunological, biochemical and biophysical properties of three hemorrhagic factors isolated from the venom of Bothrops jararaca (jararaca)

M. T. Assakura, A. P. Reichl and F. R. Mandelbaum. Comparison of immunological, biochemical and biophysical properties of three hemorrhagic factors isolated from the venom of Bothrops jararaca (jararaca). Toxicon 24, 943 - 946, 1986.—Compared to the crude velonom of Bothrops jararaca, which needs 5000 ng to produce a hemorrhagic spot of 1 cm 2 on rabbit skin, the isolated hemorrhagic factors HF 1, HF 2 and HF 3 require 100, 20 and 15 ng of protein, respectively. Although these hemorrhagic factors possess different biochemical and biophysical properties, they are immunologically related proteins. The hemorrhagic, as well as the proteolytic, activities of these factors are destroyed by EDTA, acidic pH or heat treatments.