scholarly journals Purification and properties of N-acetylgalactosamine 6-sulphate sulphatase from human placenta

1979 ◽  
Vol 181 (1) ◽  
pp. 37-46 ◽  
Author(s):  
Josef Glössl ◽  
Wolfgang Truppe ◽  
Hans Kresse
Keyword(s):  
Human Placenta ◽  
Sodium Acetate ◽  
Heparan Sulphate ◽  
Sodium Dodecyl ◽  
Acetate Buffer ◽  
Major Protein ◽  
Sodium Acetate Buffer ◽  
Ph Optimum ◽  
Enzyme Preparations ◽  
Major Protein Band

1. N-Acetylgalactosamine 6-sulphate sulphatase was purified about 20000-fold from the soluble extract of human placenta with N-acetylgalactosamine 6-sulphate–glucuronic acid–N-acetyl[1-3H]galactosaminitol 6-sulphate as substrate in the activity assay. The enzyme appears to be a glycoprotein with a mol.wt. of about 100000 as determined by gel filtration. On gel electrophoresis in the presence of sodium dodecyl sulphate the major protein band had a mol.wt. of 78000. Variable charge heterogeneity was observed in several enzyme preparations. 2. The purified enzyme released up to one sulphate molecule from the disulphated trisaccharide. It was active towards N-acetylgalactosamine 6-sulphate and exhibited no measurable N-acetylglucosamine 6-sulphate sulphatase or any other known lysosomal sulphatase activity. Hydrolysis of [1-3H]galactitol 6-sulphate was achieved by incubation neither with a crude nor with a purified enzyme preparation. Chondroitin 6-sulphate and keratan sulphate, as well as heparin and heparan sulphate, served as competitive inhibitors of the enzyme. 3. Purified N-acetylgalactosamine 6-sulphate sulphatase activity was optimal at pH4.9 and 4.4 when assayed in 0.02m-sodium acetate buffer and at pH4.2 and 5.2 in 0.1m-sodium acetate buffer. A single pH-optimum at pH4.8 was observed for the crude enzyme and for the purified enzyme after mild periodate treatment. The sulphatase activity was inhibited by a variety of anions and cations and activated by thiol-specific and thiol reagents.

The role of silicon in forages: A quantitative X-Ray study

1987 ◽  
Vol 45 ◽  
pp. 416-417
Author(s):  
Janet H. Woodward ◽  
D. E. Akin
Keyword(s):  
Sodium Acetate ◽  
Dry Matter ◽  
Acetate Buffer ◽  
Plant Tissues ◽  
Sodium Acetate Buffer ◽  
X Ray ◽  
Dry Matter Digestibility ◽  
Percent Composition

Silicon (Si) is distributed throughout plant tissues, but its role in forages has not been clarified. Although Si has been suggested as an antiquality factor which limits the digestibility of structural carbohydrates, other research indicates that its presence in plants does not affect digestibility. We employed x-ray microanalysis to evaluate Si as an antiquality factor at specific sites of two cultivars of bermuda grass (Cynodon dactvlon (L.) Pers.). “Coastal” and “Tifton-78” were chosen for this study because previous work in our lab has shown that, although these two grasses are similar ultrastructurally, they differ in in vitro dry matter digestibility and in percent composition of Si.Two millimeter leaf sections of Tifton-7 8 (Tift-7 8) and Coastal (CBG) were incubated for 72 hr in 2.5% (w/v) cellulase in 0.05 M sodium acetate buffer, pH 5.0. For controls, sections were incubated in the sodium acetate buffer or were not treated.

STARCH GEL ELECTROPHORESIS OF COBRA AND RATTLESNAKE VENOMS

1963 ◽  
Vol 41 (4) ◽  
pp. 1073-1078 ◽  
Author(s):  
J. M. Neelin
Keyword(s):  
Ionic Strength ◽  
Gel Electrophoresis ◽  
Sodium Acetate ◽  
Acetate Buffer ◽  
Starch Gel Electrophoresis ◽  
Two Dimensional ◽  
Sodium Acetate Buffer ◽  
Cacodylate Buffer ◽  
Starch Gel ◽  
Acidic Proteins

The effect of pH on gradient starch gel electrophoresis of the venoms of Crotalus adamanteus and Naja flava has been examined. Sodium acetate buffer, pH 4.1, ionic strength 0.020, appeared most effective for resolution of the former venom, and acetate buffer, pH 4.7, or cacodylate buffer, pH 6.0, for the latter. Two-dimensional starch gel electrophoresis resolved at least 20 zones from the crotaline venom and 11 from the colubrid. Two zones of hemolytic activity were separated from each venom: in C. adamanteus the less cationic zone included possibly two or more acidic proteins; the corresponding zone of N. flava was more basic, more homogeneous, and more active under the conditions of assay.

scholarly journals XRD Identification of Ore Minerals during Cruises: Refinement of Extraction Procedure with Sodium Acetate Buffer

Minerals ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 160
Author(s):  
Jelena Milinovic ◽  
Ágata Alveirinho Dias ◽  
Ana I. Janeiro ◽  
Manuel F. C. Pereira ◽  
Sofia Martins ◽  
...  
Keyword(s):  
Sodium Acetate ◽  
Extraction Procedure ◽  
Xrd Analysis ◽  
Acetate Buffer ◽  
Sodium Acetate Buffer ◽  
Sediment Samples ◽  
New Information ◽  
Ore Minerals ◽  
Mid Atlantic Ridge ◽  
Seafloor Sediments

The on-board identification of ore minerals during a cruise is often postponed until long after the cruise is over. During the M127 cruise, 21 cores with deep-seafloor sediments were recovered in the Trans-Atlantic Geotraverse (TAG) field along the Mid Atlantic Ridge (MAR). Sediments were analyzed on-board for physicochemical properties such as lightness (L*), pH and Eh. Selected samples were studied for mineral composition by X-ray powder diffraction (XRD). Based on XRD data, sediment samples were separated into high-, low- and non-carbonated. Removal of carbonates is a common technique in mineralogical studies in which HCl is used as the extraction agent. In the present study, sequential extraction was performed with sodium acetate buffer (pH 5.0) to remove carbonates. The ratio between the highest calcite XRD reflection in the original samples (Iorig) vs its XRD-reflection in samples after their treatment with the buffer (Itreat) was used as a quantitative parameter of calcite removal, as well as to identify minor minerals in carbonated samples (when Iorig/Itreat > 24). It was found that the lightness parameter (L*) showed a positive correlation with calcite XRD reflection in selected TAG samples, and this could be applied to the preliminary on-board determination of extraction steps with acetate buffer (pH 5.0) in carbonated sediment samples. The most abundant minerals detected in carbonated samples were quartz and Al- and Fe-rich clays. Other silicates were also detected (e.g., calcic plagioclase, montmorillonite, nontronite). In non-carbonated samples, Fe oxides and hydroxides (goethite and hematite, respectively) were detected. Pyrite was the dominant hydrothermal mineral and Cu sulfides (chalcopyrite, covellite) and hydrothermal Mn oxides (birnessite and todorokite) were mineral phases identified in few samples, whereas paratacamite was detected in the top 20 cm of the core. The present study demonstrates that portable XRD analysis makes it possible to characterize mineralogy at cored sites, in particular in both low- and high-carbonated samples, before the end of most cruises, thus enabling the quick modification of exploration strategies in light of new information as it becomes available in near-real time.

scholarly journals The recombination of dimers of immunoglobulin peptide chains

1970 ◽  
Vol 118 (5) ◽  
pp. 703-712 ◽  
Author(s):  
G. T. Stevenson ◽  
K. J. Dorrington
Keyword(s):  
Immunoglobulin G ◽  
Sodium Acetate ◽  
Optical Rotatory Dispersion ◽  
Acetate Buffer ◽  
Light Chains ◽  
Sodium Acetate Buffer ◽  
Covalent Bonds ◽  
Myeloma Protein ◽  
Disulphide Bonds ◽  
Antigenic Properties

1. Both the γ and light peptide chains of human pooled and myeloma immunoglobulin G can be prepared as non-aggregating dimers at pH5.4 in 4mm-sodium acetate buffer. The dimeric state is maintained by non-covalent bonds, since the formation of interchain disulphide bonds was prevented by alkylation of the thiol groups. In the case of the light chains there is some evidence that the dimers are in equilibrium with a small amount of monomer. 2. When such dimers of the γ and light chains are mixed at pH5.4 in 4mm-sodium acetate buffer they combine rapidly, yielding a product that resembles the original immunoglobulin G in its physicochemical and antigenic properties. However, the original optical rotatory dispersion spectrum was regained only with the homogeneous myeloma protein. The recombined pooled immunoglobulin G had a spectrum slightly different from the original, suggesting that at least some of the recombinant molecules had not regained native conformations. 3. Dimers of γ chains stabilized by interchain disulphide bonds were able to recombine with light chains. However, light chains stabilized in the dimeric state by interchain disulphide bonds would not combine with γ chains. 4. The chains of rabbit immunoglobulin G behave similarly to the human chains in this system, apart from the alkylated light chains showing clearer evidence of monomeric components.

Partial purification and characterization of isopenicillin N epimerase activity from Streptomyces clavuligerus

1983 ◽  
Vol 29 (11) ◽  
pp. 1526-1531 ◽  
Author(s):  
Susan E. Jensen ◽  
Donald W. S. Westlake ◽  
Saul Wolfe
Keyword(s):  
Pyridoxal Phosphate ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Streptomyces Clavuligerus ◽  
Enzymic Activity ◽  
Partial Purification ◽  
Major Protein ◽  
Major Protein Band ◽  
Isopenicillin N

Epimerase activity, which converts isopenicillin N to penicillin N, has been partially purified from cell-free extracts of Streptomyces clavuligerus. No stimulating cofactors of this activity were found, and neither EDTA nor anaerobic incubation caused significant inhibition of activity. Although pyridoxal phosphate did not stimulate epimerase activity, the presence of this cofactor was necessary for the stabilization of enzymic activity during the purification process. Epimerase activity was purified 35.5-fold by a combination of salt precipitation, gel filtration, and ion exchange chromatography. Gel filtration indicated that the epimerase has a molecular weight of 60 000 and sodium dodecyl sulphate – polyacrylamide gel electrophoresis of the 35.5-fold purified epimerase showed a major protein band running near that location. Pyridoxal phosphate antagonists did not uniformly inhibit epimerase activity, but the inhibitory effect of hydroxylamine could be partially reversed by pyridoxal phosphate.

SOME CHARACTERISTICS OF BRAIN TYROSINE HYDROXYLASE

1967 ◽  
Vol 45 (10) ◽  
pp. 1557-1563 ◽  
Author(s):  
E. G. McGeer ◽  
S. Gibson ◽  
P. L. McGeer
Keyword(s):  
Tyrosine Hydroxylase ◽  
Rat Brain ◽  
Phosphate Buffer ◽  
Sodium Acetate ◽  
Acetate Buffer ◽  
Sodium Acetate Buffer ◽  
Optimum Conditions ◽  
Hydroxylase Activity ◽  
Michaelis Constant ◽  
Brain Tyrosine Hydroxylase

Tyrosine hydroxylase from brain homogenates differed from tyrosine hydroxylase from adrenal homogenates in being particle-bound, insensitive to cofactors, possessing a lower Michaelis constant for tyrosine, and being responsive to slightly different optimum conditions of pH and buffer. The combination of 0.02 M mercaptoethanol and 0.1–1.0 mM 2-amino-4-hydroxy-6,7-dimethyltetrahydropteridine (DMPH4) increased tyrosine hydroxylase activity in beef adrenal homogenates 15-fold, but was without effect on activity in rat brain homogenates. The Km for tyrosine in beef adrenal homogenates was 4 × 10−6 M, and in rat brain homogenates was 0.45 × 10−6 M. Conversion in beef adrenal homogenates was maximum in 0.6 M sodium acetate buffer, pH 6.0, and in rat brain homogenates was maximum in 0.28 M phosphate buffer, pH 6.2.

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