scholarly journals Biophysical characterization of Artemia salina (L.) extracellular haemoglobins

1981 ◽  
Vol 193 (1) ◽  
pp. 353-359 ◽  
Author(s):  
E J Wood ◽  
C Barker ◽  
L Moens ◽  
W Jacob ◽  
J Heip ◽  
...  
Keyword(s):  
High Speed ◽  
Artemia Salina ◽  
Low Ph ◽  
Sedimentation Equilibrium ◽  
Guanidinium Chloride ◽  
Electron Microscopic ◽  
Biophysical Characterization ◽  
Molecular Weights ◽  
Dimeric Model

Sedimentation coefficients (s0 20,w) of 11.57 +/- 0.10 S and 11.52 +/- 0.09 S were assigned for Artemia salina (L.) extracellular haemoglobins II and III respectively. These values are not significantly different. The molecular weights, M0w and M0z, of the native haemoglobins as determined by the high-speed sedimentation-equilibrium method were for haemoglobin II 239 400 +/- 7200 and 240 400 +/- 2600 respectively, and for haemoglobin III 216 300 +/- 6500 and 219 300 +/- 4500 respectively. The observed increase of Mapp. with concentration suggested that association was occurring over the concentration range investigated. Exposure of haemoglobin II to either 6 M-guanidinium chloride or to low pH (pH 4) resulted in dissociation to units of approximately half the size of the native protein, with molecular weights approx. 115 000. Electron-microscopic observations indicated a molecular structure composed of two stacked lobed discs. These results strongly support the dimeric model for Artemia haemoglobins proposed by Moens & Kondo [(1978) Eur. J. Biochem. 82, 65-72].

Molecular weights of the α chains of chicken bone collagen by high-speed sedimentation equilibrium

Biochemistry ◽  
1969 ◽  
Vol 8 (6) ◽  
pp. 2609-2615 ◽  
Author(s):  
Elton P. Katz ◽  
Camille J. Francois ◽  
Melvin J. Glimcher
Keyword(s):  
High Speed ◽  
Bone Collagen ◽  
Sedimentation Equilibrium ◽  
Molecular Weights ◽  
Chicken Bone

scholarly journals Studies on the structure of hyaluronic acid. Characterization of the product formed when hyaluronic acid is treated with ascorbic acid

1969 ◽  
Vol 114 (4) ◽  
pp. 819-825 ◽  
Author(s):  
David A. Swann
Keyword(s):  
Ascorbic Acid ◽  
Hyaluronic Acid ◽  
Sedimentation Equilibrium ◽  
Connective Tissues ◽  
Molecular Weights ◽  
The Matrix ◽  
Molecular Sizes ◽  
Equilibrium Analyses ◽  
Physical And Chemical

Physical and chemical methods were used to characterize hyaluronic acid before (fraction HAIIBI) and after (fraction HA-AA) treatment with ascorbic acid. Fraction HA-AA was recovered with an almost quantitative yield and was shown to be chemically identical with fraction HAIIBI by all the methods used. These two materials, however, differed markedly in their molecular sizes and degree of polydispersity. By using sedimentation, diffusion and sedimentation-equilibrium analyses, weight-average molecular weights of about 1·2×106 and 6·5×104 respectively were obtained for fractions HAIIBI and HA-AA. It is concluded from these results that hyaluronic acid has a molecular weight of about 65000 and that the polysaccharide chain of this molecule is not depolymerized by ascorbic acid. It is further proposed that hyaluronic acid molecules in the matrix of connective tissues are present either in an aggregated form or as subunits of heterogeneous macromolecules, and that it is the linkages responsible for the organization of these structures which are broken by ascorbic acid.

scholarly journals Molecular weights of the Thy-1 glycoproteins from rat thymus and brain in the presence and absence of deoxycholate

1978 ◽  
Vol 169 (2) ◽  
pp. 411-417 ◽  
Author(s):  
P W Kuchel ◽  
D G Campbell ◽  
A N Barclay ◽  
A F Williams
Keyword(s):  
Molecular Weight ◽  
Equilibrium Dialysis ◽  
Sedimentation Coefficient ◽  
Sedimentation Equilibrium ◽  
Membrane Glycoproteins ◽  
Guanidinium Chloride ◽  
Molecular Weights ◽  
Methionine Residue ◽  
Disulphide Bonds ◽  
Binding Data

1. The Thy-1 membrane glycoproteins from rat thymus and brain bound deoxycholate to 24% of their own weight as measured by equilibrium dialysis. The binding occurred co-operatively at the critical micelle concentration of deoxycholate, suggesting that the glycoproteins bind to a micelle, and not to the detergent monomer. 2. From sedimentation-equilibrium and deoxycholate-binding data the molecular weights of the glycoprotein monomers were calculated to be 18700 and 17500 for thymus and brain Thy-1 glycoprotein monomers were calculated to be 18700 and 17500 for thymus and brain Thy-1 glycoproteins respectively. The molecular weight of the polypeptide part of the glycoprotein is thus 12500. 3. In the absence of deoxycholate, brain or thymus Thy-1 glycoprotein formed large homogeneous complexes of mol. wt. 270000 or 300000 respectively. The sedimentation coefficient of these was 12.8 S. The complex was only partially dissociated by 4M-guanidinium chloride. 4. After cleavage of brain or thymus Thy-1 glycoprotein with CNBr, two peptides were clearly identified. They were linked by disulphide bonds and both contained carbohydrate. This cleavage suggests there is only one methionine residue per molecule, which is consistent with the above molecular weights and the known amino acid composition.

scholarly journals Haemoglobin from the tadpole shrimp, Lepidurus apus lubbocki Characterization of the molecule and determination of the number of polypeptide chains

1979 ◽  
Vol 183 (2) ◽  
pp. 325-330 ◽  
Author(s):  
E Ilan ◽  
E Daniel
Keyword(s):  
Molecular Weight ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Sedimentation Coefficient ◽  
Sedimentation Equilibrium ◽  
Guanidinium Chloride ◽  
Tadpole Shrimp ◽  
Polypeptide Chains

Haemoglobin from the tadpole shrimp, Lepidurus apus lubbocki, was found to have a sedimentation coefficient (s020,w) of 19.3 +/- 0.2 S and a molecular weight, as determined by sedimentation equilibrium, of 798000 +/- 20000. The amino acid composition showed the lack of cysteine and cystine residues. A haem content of 3.55 +/- 0.03% was determined, corresponding to a minimal mol.wt. of 17400 +/- 200. The pH-independence in the range pH 5-11 of the sedimentation coefficient indicates a relatively high stability of the native molecule. Sodium dodecyl sulphate/polyacrylamide-gel electrophoresis gave one band with mobility corresponding to a mol.wt. of 34000 +/- 1500. The molecular weight of the polypeptide chain was determined to be 32800 +/- 800 by sedimentation equilibrium in 6 M-guanidinium chloride and 0.1 M-2-mercaptoethanol. The findings indicate that Lepidurus haemoglobin is composed of 24 identical polypeptide chains, carrying two haem groups each.

The Isolation and Characterization of a Ternary Human Plasmin B-Chain-Streptokinase-Plasminogen Complex

1987 ◽  
Vol 58 (02) ◽  
pp. 772-777 ◽  
Author(s):  
Louis Summaria ◽  
Irena Boreisha ◽  
Grant H Barlow ◽  
Kenneth C Robbins
Keyword(s):  
Ternary Complex ◽  
Double Diffusion ◽  
Sedimentation Equilibrium ◽  
Molar Ratio ◽  
Molecular Weights ◽  
Isolation And Characterization ◽  
Human Plasminogen ◽  
Equilibrium Analyses ◽  
Species Specific

SummaryA ternary equimolar human plasmin B-chain-streptokinase-plasminogen complex was isolated from a mixture of the plasmin B-chain-streptokinase complex and human plasminogen at 0° C and 37° C. A ternary complex which was shown to be species specific, was identified and characterized by ultracentrifugal, acrylamide gel electrophoretic, and agarose double diffusion analyses. When mixed at a 1:1 molar ratio at 0° C, 39.9% of the preparation existed as a plasmin B-chain-streptokinase-plasmino-gen complex; when mixed at 37° C, 86.d% existed as a complex, which was identified by electrophoretic analyses to be a plasmin B-chain-streptokinase-plasmin complex. Sedimentation velocity analyses gave s°2o,w values of 3.79 for the plasmin B-chain-streptokinase complex, 4.10 for Lys-plasmin, and 6.23 for the plasmin B-chain-streptokinase-plasmin complex. Sedimentation equilibrium analyses gave molecular weights of 73,900 for the plasmin B-chain-streptokinase complex, 82,900 for Lys-plasmin, and 153,100 for the plasmin B-chain-streptokinase-plasmin complex. The diisopropylphosphorofluoridatc (DFP)-inhibitcd and the p-nitrophenyl-p-guanidino-benzoate (NPGB)-inhibited plasmin B-chain-streptokinase complexes both retained their ability to form a ternary complex with human plasminogen, but this complex did not convert to a plasmin B-chain-streptokinase-plasmin complex. Thus, the active site serine residue is essential for the activator activity of the plasmin B-chain-streptokinase complex, but it is not necessary for the binding of the plasmin B-chain-streptokinase complex to plasminogen to form a ternary complex.

scholarly journals Isolation and characterization of human cervical-mucus glycoproteins

1983 ◽  
Vol 211 (1) ◽  
pp. 13-22 ◽  
Author(s):  
I Carlstedt ◽  
H Lindgren ◽  
J K Sheehan ◽  
U Ulmsten ◽  
L Wingerup
Keyword(s):  
Density Gradient ◽  
Proteinase Inhibitors ◽  
Density Gradient Centrifugation ◽  
Gradient Centrifugation ◽  
Disc Electrophoresis ◽  
Guanidinium Chloride ◽  
Molecular Weights ◽  
Isolation And Characterization ◽  
Mucus Glycoproteins

Mucus glycoproteins (mucins) were extracted from human cervical pregnancy mucus by 6 M-guanidinium chloride in the presence of proteinase inhibitors. Purification was subsequently achieved by isopycnic density-gradient centrifugation in CsCl/ guanidinium chloride gradients. The purified macromolecules represented approx. 85% of the total and were devoid of nucleic acids and proteins, as judged by analytical density-gradient centrifugation, disc electrophoresis and u.v. spectroscopy. Sedimentation-velocity centrifugation revealed a single unimodal peak with S20,W 50.1S in 0.2M-NaCl and 37.0S in 6 M-guanidinium chloride. Molecular weights obtained by light-scattering were 9.7 × 10(6) and 5.9 × 10(6) in 0.2M-NaCl and 6 M-guanidinium chloride respectively. The chemical analyses were typical of those of epithelial mucins. The macromolecules contained approx. 20% (w/w) of protein, and 65% (w/w) was accounted for as carbohydrate. Serine and threonine constituted 32 mol/100 mol and proline 10 mol/100 mol of the amino acids. The major sugars found were N-acetylglucosamine (12.8%), N-acetylgalactosamine (9.7%), galactose (18.7%), sialic acid (15.0%) and fucose (7.5%).

scholarly journals ELECTRON MICROSCOPIC AND BIOCHEMICAL CHARACTERIZATION OF COLLAGEN IN BLATTARIAN INSECTS

1967 ◽  
Vol 33 (2) ◽  
pp. 385-393 ◽  
Author(s):  
Elvin Harper ◽  
Sam Seifter ◽  
Berta Scharrer
Keyword(s):  
Trichloroacetic Acid ◽  
Biochemical Characterization ◽  
Corpus Allatum ◽  
Corpus Cardiacum ◽  
Guanidinium Chloride ◽  
Concentrated Solutions ◽  
Electron Microscopic ◽  
Bacterial Collagenase ◽  
Leucophaea Maderae

The occurrence of collagen in the cockroach Leucophaea maderae has been demonstrated by electron optical and biochemical techniques. Electron micrographs of tissues of this and a related species (Blaberus craniifer) are presented and they show that collagenous-type fibers occur in the stroma of nonneural as well as neural organs of these insects. Hydroxyproline and hydroxylysine, amino acids considered to be "markers" for collagen, have been shown to be present in proteins extracted from material rich in neuroglandular tissue (corpus cardiacum plus corpus allatum). Trimmed carcasses of Leucophaea maderae have been shown to contain a protein or proteins soluble in hot trichloroacetic acid, with compositional characteristics similar to those of collagens in general, including diagnostic proportions of glycine, proline, hydroxyproline, and hydroxylysine. This collagen is not soluble in dilute acetic acid or in concentrated solutions of guanidinium chloride. It is measurably digested by bacterial collagenase.

Improved purification and further characterization of Clostridium perfringens type A enterotoxin

1973 ◽  
Vol 19 (11) ◽  
pp. 1379-1382 ◽  
Author(s):  
A. H. W. Hauschild ◽  
R. Hilsheimer ◽  
W. G. Martin
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Clostridium Perfringens ◽  
Amino Acid Analysis ◽  
Sedimentation Coefficient ◽  
Type A ◽  
Sedimentation Equilibrium ◽  
Molecular Weights ◽  
Hydrolysis Of

The procedure for the purification of Clostridium perfringens type A enterotoxin was simplified, and the purity of the toxin was improved. Hydrolysis of the toxin by the p-toluenesulfonic acid procedure yielded 18 common amino acids. Among these, aspartic acid, serine, leucine, and glutamic acid were the predominant components. The sedimentation coefficient (s°20, w) was 2.8 Svedberg units. The molecular weights determined by the Archibald technique, sedimentation equilibrium, and amino acid analysis were 40 000, 36 000, and 33 000, respectively.

scholarly journals Isolation, characterization and oxygen equilibrium of an extracellular haemoglobin from Eunice aphroditois (Pallas)

1976 ◽  
Vol 159 (1) ◽  
pp. 35-42 ◽  
Author(s):  
J V Bannister ◽  
W H Bannister ◽  
A Anastasi ◽  
E J Wood
Keyword(s):  
Minor Component ◽  
Sedimentation Equilibrium ◽  
Hill Coefficient ◽  
Electron Microscopic ◽  
Microscopic Appearance ◽  
Molecular Weights ◽  
Ph Values ◽  
Electron Microscopic Appearance ◽  
Ph Range ◽  
The Hill

The extracellular haemoglobin from the polychaeta,Eunice aphroditois, existed as a mixture of a heavy major component (so20, w = 56.96 +/- 0.125) and a light minor component (so20, w = 10.00 +/- 0.13S), the latter probably being a dissociation product of the former. The molecular weight of the purified heavier component, as detetermined by sedimentation equilibrium, was 3.44 X 10(6) +/- 0.04X10(6). The molecule had the electron-microscopic appearance typical of annelid haemoglobins, consisting of a stack of two hexagonal plates, with dimensions 26.32 +/- 0.27 nm across the flats of the hexagon, height of stack 17.86 +/- 0.34 nm. The sugar composition is reported, and the isoelectric point was approx. pH7.8. The haem content was 2.31 +/- 0.01%, corresponding to a minimal mol.wt. of 26700. Detergent/gel electrophoresis revealed the presence of at least four bands with molecular weights in the range 14600-31000. Five N-terminal amino acids were found. In addition to the 10S component, which co-existed with the 57S component at all pH values in the range 4.0-10.6, at low pH values (less than pH.5.0) A 16S and a 1.9 S component were found. The absorption and circular-dichroic spectra are reported, and the alpha-helical content, calculated from the ellipticity at 222 nm, was about 40%. The molecule bound O2 co-operatively with a maximum value of the Hill coefficient, h, of 3.9. Over the pH range 7.0-8.0 there was a positive Bohr effect.

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