scholarly journals Characterization of a maternal type VI collagen in Xenopus embryos suggests a role for collagen in gastrulation.

1990 ◽  
Vol 111 (1) ◽  
pp. 271-278 ◽  
Author(s):  
A P Otte ◽  
D Roy ◽  
M Siemerink ◽  
C H Koster ◽  
F Hochstenbach ◽  
...  
Keyword(s):  
Extracellular Matrix ◽  
Amino Acid ◽  
Matrix Element ◽  
Culture Medium ◽  
Collagen Type ◽  
Developmental Stages ◽  
Molecular Weights ◽  
Collagen Type Vi ◽  
Cell Layers

We characterized a novel extracellular matrix element that is present in the earliest developmental stages of Xenopus laevis, and is recognized by an mAb 3D7. Based on amino acid composition, breakdown patterns by bacterial collagenases, and the molecular weights of the components of the antigen (240, 200, and 140 kD), we found it very similar to mammalian collagen type VI. The antigen is evenly distributed in unfertilized eggs. Shortly after fertilization, it becomes localized intracellularly in the periphery of the cleaving embryo as well as in the extracellular spaces. During gastrulation, the antigen was localized in the cells lining the blastopore and in the extracellular space between the two cell layers, in the presumptive archenteron. When Fab elements of the 3D7 antibody were added to the culture medium, gastrulation was blocked, suggesting a role for the antigen in gastrulation movements.

scholarly journals α-Crystallin. The isolation and characterization of distinct macromolecular fractions

1971 ◽  
Vol 124 (2) ◽  
pp. 337-343 ◽  
Author(s):  
Abraham Spector ◽  
Lu-Ku Li ◽  
Robert C. Augusteyn ◽  
Arthur Schneider ◽  
Thomas Freund
Keyword(s):  
Molecular Weight ◽  
Amino Acid ◽  
Gel Filtration ◽  
Deae Cellulose ◽  
Chemical Difference ◽  
Molecular Weights ◽  
Isolation And Characterization ◽  
Different Populations ◽  
Molecular Weight Fractions

α-Crystallin was isolated from calf lens periphery by chromatography on DEAE-cellulose and gel filtration. Three distinct populations of macromolecules have been isolated with molecular weights in the ranges approx. 6×105−9×105, 0.9×106−4×106and greater than 10×106. The concentration of macromolecules at the molecular-weight limits of a population are very low. The members of the different populations do not appear to be in equilibrium with each other. Further, in those molecular-weight fractions investigated, no equilibrium between members of the same population was observed. The population of lowest molecular weight comprises 65–75% of the total material. The amino acid and subunit composition of the different-sized fractions appear very similar, if not identical. The only chemical difference observed between the fractions is the presence of significant amounts of sugar in the higher-molecular-weight fractions. Subunit molecular weights of approx. 19.5×103and 22.5×103were observed for all α-crystallin fractions.

scholarly journals cDNA Cloning and Partial Characterization of the DJ-1 Gene from Tribolium castaneum

Antioxidants ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 1970
Author(s):  
Shunya Sasaki ◽  
Maaya Nishiko ◽  
Takuma Sakamoto ◽  
Michael R. Kanost ◽  
Hiroko Tabunoki
Keyword(s):  
Oxidative Stress ◽  
Amino Acid ◽  
Tribolium Castaneum ◽  
Cdna Sequence ◽  
Developmental Stages ◽  
Red Flour Beetle ◽  
Genome Database ◽  
Antioxidant Function ◽  
Increased Sensitivity

The DJ-1 gene is highly conserved across a wide variety of organisms and it plays a role in anti-oxidative stress mechanisms in cells. The red flour beetle, Tribolium castaneum, is widely used as a model insect species because it is easy to evaluate gene function in this species using RNA interference (RNAi). The T. castaneum DJ-1 (TcDJ-1) sequence is annotated in the T. castaneum genome database; however, the function and characteristics of the TcDJ-1 gene have not been elucidated. Here, we investigated the cDNA sequence of TcDJ-1 and partially characterized its function. First, we examined the TcDJ-1 amino acid sequence and found that it was highly conserved with sequences from other species. TcDJ-1 mRNA expression was higher in the early pupal and adult developmental stages. We evaluated oxidant tolerance in TcDJ-1 knockdown adults using paraquat and found that adults with TcDJ-1 knockdown exhibited increased sensitivity to paraquat. Our findings show that TcDJ-1 has an antioxidant function, as observed for DJ-1 from other insects. Therefore, these results suggest that TcDJ-1 protects against oxidative stress during metamorphosis.

scholarly journals Biochemical characterization of a second family of human Ia molecules, HLA-DS, equivalent to murine I-A subregion molecules.

1982 ◽  
Vol 156 (2) ◽  
pp. 550-566 ◽  
Author(s):  
S M Goyert ◽  
J E Shively ◽  
J Silver
Keyword(s):  
Amino Acid ◽  
Amino Acid Sequence ◽  
Amino Acid Sequence Identity ◽  
Biochemical Characterization ◽  
Amino Acid Sequence Homology ◽  
Molecular Weights ◽  
Hla Dr ◽  
D Region ◽  
Polypeptide Chains

In mice, two families of structurally distinct Ia molecules, one designated I-A and the other I-E, have been identified and characterized. The HLA-DR molecules represent one family of human Ia molecules equivalent to the murine I-E molecules on the basis of amino acid sequence homology. We describe the isolation and biochemical characterization of a second family of human Ia molecules, designated HLA-DS for second D-region locus, equivalent to the murine I-A molecules. The human HLA-DS molecules consist of two polypeptide chains, DS alpha (37,000 mol wt) and DS beta (29,000 mol wt), with 73% amino acid sequence identity to the murine I-A molecules. Furthermore, the HLA-DS molecules are closely linked genetically to HLA-DR molecules, a situation analogous to that observed in mice. The similarity in molecular weights of the DR and DS molecules might explain why others have failed to identify the latter in man.

scholarly journals Characterization of three constituent chains of collagen type VI by peptide sequences and cDNA clones

1987 ◽  
Vol 168 (2) ◽  
pp. 309-317 ◽  
Author(s):  
Mon-Li CHU ◽  
Karlheinz MANN ◽  
Rainer DEUTZMANN ◽  
Dorothy PRIBULA-CONWAY ◽  
Chuen-Chin HSU-CHEN ◽  
...  
Keyword(s):  
Collagen Type ◽  
Cdna Clones ◽  
Collagen Type Vi

scholarly journals Purification and Partial Characterization of Rat Fibrinogen (rat-Fbg)

1977 ◽  
Author(s):  
W. Nieuwenhuizen ◽  
Irina A.M. van Ruijven-Vermeer
Keyword(s):  
Amino Acid ◽  
Gel Electrophoresis ◽  
Proteolytic Enzymes ◽  
Mammalian Species ◽  
Rat Plasma ◽  
Gel Chromatography ◽  
Molecular Weights ◽  
Ammonium Sulphate Precipitation ◽  
Proteolytic Activities

Rat-Fbg was purified from rat plasma using Sepharose-1ysi ne chromatography, repeated ammonium sulphate precipitation (35% saturation) and gel chromatography on Sepharose 6B.In order to minimize proteolytic activity, rats were injected intravenously with Trasylol before bleeding, and the collected blood was treated with Trasylol and DFP.A preparation was obtained, which was 95% clottable and showed a single band on SDS-poly-acrylamide gel electrophoresis. Alanine was the only detectable am i no-term i na 1 amino acid.After reduction and modification of the SH groups the material could be separated into three distinct chains (Aα, Bβ and γ) by pore-limit Polyacrylamide slab-gel electrophoresis in sod i urn dodecyl sulphate. The amino acid composition of the whole Fbg and of the separated modified chains were determined. The molecular weights were 61,000, 58,000 and 51,000 for Aα, Bβ and γ-chains, respectively.In as far as the chains are concerned, our results are in contrast with the findings of Bouma et al. (J. Biol. Chem. 250(1975) 4678), who could not discriminate between Aα- and Bβ-chains in SDS-polyacry1 am i de gel electrophoresis. Evidence will be presented that this can be due to Aa-chain degradation caused by incomplete inhibition of proteolytic enzymes during the purification.It is concluded, that complete inhibition of proteolytic activities in all purification steps is essential to obtain native fibrinogen. Moreover, in contrast to the conclusions of Bouma rat-Fbg does not differ essentially from Fbg from other mammalian species.

scholarly journals Isolation and characterization of keratin-like proteins from cultured cells with fibroblastic morphology.

1984 ◽  
Vol 98 (4) ◽  
pp. 1231-1237 ◽  
Author(s):  
R V Zackroff ◽  
A E Goldman ◽  
J C Jones ◽  
P M Steinert ◽  
R D Goldman
Keyword(s):  
Amino Acid ◽  
Secondary Structure ◽  
Cultured Cells ◽  
Coiled Coil ◽  
Uranyl Acetate ◽  
3T3 Cells ◽  
Immunological Properties ◽  
Molecular Weights ◽  
Isolation And Characterization

Intermediate filaments (IF) isolated from a variety of cultured cells, conventionally described as fibroblasts, are composed predominantely of proteins of molecular weights of 54,000 and/or 55,000. Less than 15% of the protein found in native IF preparations from these cells is composed of three to four polypeptides of molecular weights 60,000-70,000. We have investigated some biochemical and immunological properties of these proteins isolated from BHK-21 and mouse 3T3 cells. They are capable of forming paracrystals that exhibit a light/dark banding pattern when negatively stained with uranyl acetate. The dark bands are composed of longitudinally aligned approximately 2-nm-diam filaments. The center-to-center spacing between either dark or light bands is 37-40 nm. These dimensions are consistent with the secondary structure of IF polypeptides and suggest that the dark bands represent lateral alignment of alpha-helical coiled-coil domains. Immunoblotting, secondary structure, as well as amino acid composition data indicate that the 60,000-70,000-mol-wt paracrystal polypeptides are similar to keratin. Thus, polypeptides with biochemical and immunological properties of epidermal keratin are present in cells normally considered to be fibroblasts.

Production and Characterization of Ovalbumin and Ovotransferrin from Chicken Egg White

2012 ◽  
Vol 8 (2) ◽  
Author(s):  
Jianguo Liu ◽  
Jing Liu ◽  
Xuefang Zhang
Keyword(s):  
Amino Acid ◽  
Binding Capacity ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Egg White ◽  
Molecular Weights ◽  
Chicken Egg ◽  
Isoelectric Points ◽  
Iron Binding Capacity

An efficient and easily scaled up method to separate ovalbumin and ovotransferrin simultaneously from chicken egg white using ultrafiltration is proposed. The purities of ovalbumin and ovotransferrin obtained were 94% and 89%, with the yields of 82% and 76%, respectively. The resulting ovalbumin and ovotransferrin products was then characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, isoelectric focusing, dynamic light scattering, circular dichroism, and amino acid analysis to confirm their molecular weights, isoelectric points, aggregate sizes, molecular secondary structures, and amino acid compositions. The iron-binding capacity of the purified ovotransferrin was also evaluated.

Characterization of excretory-secretory antigens of Fasciola hepatica

Parasitology ◽  
1982 ◽  
Vol 85 (1) ◽  
pp. 179-188 ◽  
Author(s):  
D. O. Irving ◽  
M. J. Howell
Keyword(s):  
Molecular Weight ◽  
Culture Medium ◽  
Fasciola Hepatica ◽  
Culture Media ◽  
Minor Component ◽  
Serum Free Medium ◽  
Molecular Weights ◽  
A Minor ◽  
Somatic Antigens

SUMMARYTwenty-one day old Fasciola hepatica were recovered from the livers of infected mice and cultured for 5–7 days in a serum-free medium containing either [C]leucine, [C]isoleucine or [S]methionine, or in a medium containing [C]leucine and serum from a sheep vaccinated with excretory– secretory (ES) antigens of juvenile F. hepatica. All three labelled amino acids were incorporated into fluke proteins. Labelled proteins also appeared in the culture medium. Three major polypeptides detected in the culture media had apparent molecular weights of 26000, 24000 and 23000. All were immunoprecipitated from [C]leucine-labelled culture medium using antisera against fluke somatic antigens raised in rabbits or from sheep vaccinated with ES antigens of juvenile F. hepatica. A polypeptide of molecular weight 27 000 was also prominent in the culture medium when [C]isoleucine was used. This polypeptide was present as a minor component when [C]leucine and [S]methionine were included in the culture media; it did not appear to be immunoprecipitated by the above antisera from [C]leucine-labelled culture medium. In the presence of serum from vaccinated sheep, the ES antigens formed immune complexes which contained the polypeptides mentioned above, together with several higher molecular weight polypeptides. Additionally, a number of minor bands of varying molecular weight were present. After micro-Ouchterlony gel immunodiffusion, 2 precipitin lines formed between the labelled ES antigens and antisera. Electrophoresis of these indicated that the 23000, 24000 and 26000 Dalton labelled polypeptides were present in each. The higher molecular weight and the 27000 Dalton labelled polypeptides were also present in one of the lines.

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