(1/3737) The isolation and partial characterization of the serum lipoproteins and apolipoproteins of the rainbow trout.
1. VLD (very-low-density), LD (low-density) and HD (high-density) lipoproteins were isolated from the serum of trout (Salmo gairdneri Richardson). 2. Each lipoprotein class resembled that of the human in immunological reactivity, electrophoretic behaviour and appearance in the electron microscope. Trout LD lipoprotein, however, was of greater density than human LD lipoprotein. 3. The trout lipoproteins have lipid compositions which are similar to those of the corresponding human components, except for their high contents of long-chain unsaturated fatty acids. 4. HD and LD lipoproteins were immunologically non-identical, whereas LD lipoproteins possessed antigenic determinants in common with VLD lipoproteins. 5. VLD and HD lipoproteins each contained at least seven different apoproteins, whereas LD liprotein was composed largely of a single apoprotein which resembled human apolipoprotein B. 6. At least one, and possibly three, apoprotein of trout HD lipoprotein showed features which resemble human apoprotein A-1.7. The broad similarity between the trout and human lipoprotein systems suggests that both arose from common ancestral genes early in evolutionary history. (+info)
(2/3737) Studies of the binding of different iron donors to human serum transferrin and isolation of iron-binding fragments from the N- and C-terminal regions of the protein.
1. Trypsin digestion of human serum transferrin partially saturated with iron(III)-nitrilotriacetate at pH 5.5 or pH 8.5 produces a carbohydrate-containing iron-binding fragment of mol.wt. 43000. 2. When iron(III) citrate, FeCl3, iron (III) ascorabate and (NH4)2SO4,FeSO4 are used as iron donors to saturate the protein partially, at pH8.5, proteolytic digestion yields a fragment of mol.wt. 36000 that lacks carbohydrate. 3. The two fragments differ in their antigenic structures, amino acid compositions and peptide 'maps'. 4. The fragment with mol.wt. 36000 was assigned to the N-terminal region of the protein and the other to the C-terminal region. 5. The distribution of iron in human serum transferrin partially saturated with various iron donors was examined by electrophoresis in urea/polyacrylamide gels and the two possible monoferric forms were unequivocally identified. 6. The site designated A on human serum transferrin [Harris (1977) Biochemistry 16, 560--564] was assigned to the C-terminal region of the protein and the B site to the N-terminal region. 7. The distribution of iron on transferrin in human plasma was determined. (+info)
(3/3737) Mushroom worker's lung resulting from indoor cultivation of Pleurotus osteatus.
Indoor cultivation of oyster mushroom Pleurotus osteatus lead to an outbreak of extrinsic allergic alveolitis in two workers. High titer of indirect fluorescent antibody and positive precipitins against basidiospores of P. osteatus were demonstrated in sera of the patients. Mushroom workers should protect themselves from the basidiospores, being aware of their pathogenicity. (+info)
(4/3737) Chemical and immunochemical measurement of total iron-binding capacity compared.
Radiometric, colorimetric, and two immunochemical methods for measuring total iron-binding capacity are compared. We evaluated the procedures on the basis of precision, applicability to a pediatric population, and accuracy as assessed by analytical recovery of purified transferrin. The immunoephelometric assay for transferrin provides significant advantages over the other methods examined. (+info)
(5/3737) Purification of two dexamethasone-binding proteins from rat-liver cytosol.
Two dexamethasone-binding proteins have been purified from rat liver cytosol. The main purification steps are: precipitation by protamine sulphate, affinity chromatography on CH-Sepharose 4B to which 11-deoxycorticosterone is linked through a disulfide bond and DEAE-cellulose chromatography. Two binding components elute from the DEAE-cellulose column at 0.12 M and 0.2 M NaCl, respectively. By means of dodecylsulphate/polyacrylamide gel electrophoresis it was demonstrated that both components are composed predominantly of a single polypeptide with molecular weights of about 45 000 and 90 000. Antibodies to the two polypeptides have been elicited in rabbits. The antibodies to the 45 000-Mr polypeptide cross react with the 90 000-Mr component. Likewise the antibodies to the 90 000-Mr protein precipitate the 45 000-Mr polypeptide. Either of the two antibody preparations immunoprecipitates the major part (approximately 70%) of the dexamethasone-binding activity of the cytosol. (+info)
(6/3737) Carbohydrate on human factor VIII/von Willebrand factor. Impairment of function by removal of specific galactose residues.
Human factor VIII/von Willebrand factor protein containing 120 +/- 12 nmol of sialic acid and 135 +/- 13 nmol of galactose/mg of protein was digested with neuraminidase. The affinity of native factor VIII/von Willebrand factor and its asialo form for the hepatic lectin that specifically binds asialoglycoproteins was assessed from in vitro binding experiments. Native factor VIII/von Willebrand factor exhibited negligible affinity while binding of the asialo derivative was comparable to that observed for asialo-alpha1-acid glycoprotein. Incubation of asialo-factor VIII/von Willebrand factor with Streptococcus pneumoniae beta-galactosidase removed only 62% of the galactose but abolished binding to the purified hepatic lectin. When the asialo derivative was incubated with purified beta-D-galactoside alpha2 leads to 6 sialyltransferase and CMP-[14C]NeuAc, only 61% of the galactose incorporated [14C]NeuAc. From the known specificites of these enzymes, it is concluded that galactose residues important in lectin binding are present in a terminal Gal/beta1 leads to 4GlcNAc sequence on asialo-factor VIII/von Willebrand factor. The relative ristocetin-induced platelet aggregating activity of native, asialo-, and agalacto-factor VIII/von Willebrand factor was 100:38:12, respectively, while procoagulant activity was 100:100:103. (+info)
(7/3737) Immunological comparison of the proteins of chicken and rat liver ribosomes.
A comparison of the proteins of chicken and rat liver ribosomes using immunochemical techniques was undertaken. The procedures included quantitative precipitation, passive hemagglutination, and immunodiffusion on Ouchterlony plates. The results indicate that antisera specific for chicken or rat liver ribosomes recognize only about 20% of common determinants. While there are important reservations, the results suggest extensive differences in the proteins of rat and chicken liver ribosomes. Despite those differences, rat and chicken liver ribosomal proteins maintain some homologous sequences present in bacterial ribosomal proteins. An enriched antibody preparation against chicken 80 S ribosomes inhibited the poly(U)-directed synthesis of polyphenylalanine and the elongation factor G (EF-G)-catalyzed binding of [3H]GDP to Escherichia coli ribosomes. Thus, chicken liver ribosomes, like ribosomes from rat liver and yeast, must have proteins homologous with those of E. coli ribosomes. (+info)
(8/3737) Homogeneous pyruvate kinase isolated from yeast by two different methods is indistinguishable from pyruvate kinase in cell-free extract.
In this report, we have compared homogeneous yeast (Saccharomyces cerevisiae) pyruvate kinase to enzyme from cell-free extracts in several different ways: 1) isoelectric focusing of cell-free extracts indicates one peak of pyruvate kinase activity whose isoelectric point is the same as that of the pure enzyme; 2) antibody prepared to the pure enzyme produces a single, fused precipitin line against enzyme in the cell-free extract and pure enzyme; 3) immunoelectrophoresis of cell-free extract produces one precipitin arc which has the same mobility as that of the pure enzyme; and 4) immunoprecipitation of the pure enzyme from cell-free extract with subsequent solubilization in 1% sodium dodecyl sulfate and electrophoresis on sodium dodecyl sulfate-polyacrylamide gels produces a single protein band attributable to pyruvate kinase which co-migrates with the purified enzyme. Within the limits of the sensitivity of the methods employed, we conclude that the homogeneous pyruvate kinase prepared from yeast lysed either by Manton-Gaulin homogenization (Aust, A., Yun, S.-L., and Suelter, C. (1975) Methods Enzymol. 42, 176-182) or by toluolysis (Yun, S.-L., Aust, A.E., and Suelter, C.H. (1977) J. Biol. Chem. 251, 124-128) is identical with pyruvate kinase in cell-free extract. (+info)