Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0272170 (SDS)
 50,377 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A protein antigenically similar to the anti-encephalitogenic bovine spinal cord protein (BSCP) was detected in saline extracts of rat nervous tissues by immunodiffusion analyses using a rabbit anti-BSCP serum. Rat SCP (RSCP) appears to be evenly distributed throughout all parts of the rat nervous system and occurs also in the thymus, thyroid, and adrenal glands. Although immunodiffusion analyses indicated that RSCP shares some antigenic sites with BSCP, anti-RSCP sera reacted only with RSCP, indicating that the major immunogenic determinants of the RSCP are peculiar to the rat and differ from the immunogenic determinants of human, monkey, rabbit, guinea pig, or bovine SCP. Immunoelectrophoretic analyses of concentrated pastes of rat brain (RB) or rat spinal cord (RSC) in agar at pH 8.6 revealed that RSCP occurs in two molecular forms having the electrophoretic mobilities of a serum beta-globulin and a serum gamma-globulin, respectively. However, gamma-RSCP is the predominant component of extracts of brain or spinal cord. Gamma-RSCP was isolated from RB and RSC by a procedure which involved: a) extraction with 0.05 M ammonium acetate buffer, pH 4.0; b) batch absorption of impurities on CM-52 cellulose; c) batch absorption of RSCP on SP-Sephadex, pH 3.5; d) elution of RSCP from SP-Sephadex, pH 5.5; and finally, e) gel filtration on Sephadex G-50 superfine. Purified gamma-RSCP formed one band when analyzed by polyacrylamide electrophoresis in acid gels containing 8 M urea. In contrast, two bands were always present when gamma-RSCP from brain or spinal cord were subjected to SDS-polyacrylamide electrophoresis in 15% gels. The larger of the two components of brain gamma-RSCP had a m.w. of 12,400 daltons, whereas the two components of spinal cord gamma-RSCP were smaller. The molecular sizes of brain RSCP and spinal cord RSCP was estimated by gel filtration chromatography to be 12,400 daltons. The amino acid compositions of gamma-RSCP prepared from RB or RSC were similar except that gamma-RSCP from RSC contained twice as much half-cystine and a slightly higher proportion of basic amino acid than gamma-RSCP from RB.
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PMID:Parital characterization of the rat anti-encephalitogenic protein (RSCP). 5 40

Chicken anti-human IgD antiserum (anti-delta) has demonstrated an antigenically cross-reactive homologue on rat lymphocytes. IgD and IgM are the only cell surface immunoglobulins detectable by the lactoperoxidase radiolabeling technique employed. The results indicate that, although rat surface IgD is antigenically distinct from rat IgM, the respective H chains co-electrophorese in 10% polyacrylamide-SDS gels. Rat delta-chain has an apparent m.w. of 73,000 daltons and exhibits a minor 65,000 dalton component which probably represents a partially degraded delta-chain. The ontogenic emergence of rat IgD occurs approximately 3.5 weeks after birth whereas IgM, in contrast, is apparent by 6 days of age. Thus, as in the human, IgM develops before IgD. IgD receptors are undetectable in the thymus but are present in increasing levels in spleen, blood, lymph nodes, and Peyer's patches.
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PMID:Structure and biologic functions of human IgD. XI. Identification and ontogeny of a rat lymphocyte immunoglobulin having antigenic cross-reactivity with human IgD. 6 67

Ia-antigen-like molecules are expressed on cells within several different non-lymphoid tissues of the guinea-pig. In indirect immunofluorescence analyses anti-Ia-antigen antibodies stained epithelial cells lining the intestinal tract, the bile ducts, the respiratory tract and the urinary tract. The rabbit antibodies against Ia antigens also stained the cells of the parotid and the submandibular glands. Evidence was also obtained suggesting that the reticuloepithelial cells of the thymus, like the Kupffer cells of the liver, express Ia-antigen-like molecules. In several cases indirect immunoprecipitation analyses and SDS-polyacrylamide gel electrophoresis confirmed the immunofluorescence studies inasmuch as Ia-antigen-like subunits with apparent molecular weights of 26,000 and 34,000 could be isolated from the non-lymphoid organs.
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PMID:Distribution of Ia-antigen-like molecules on non-lymphoid tissues. 8 9

LSHr, a protein from thymus, was shown to be a single pure peptide of 80,000 daltons by its migration in Sephadex G-150, SEDImentation velocity ultracentrifugation, both regular and SDS gel electrophoresis, and isoelectric focusing as a single symmetrical peak. It promoted the differentiation of T-lymphocytes in in vitro and in vivo tests. Human bone marrow cells showed differentiation in response to LSHr treatment to express a surface marker unique to T-cells following incubation with 10(-14) to 10(-9) M LSHr. Control proteins showed no effect. In preliminary experiments, administration of microgram quantities of LSHr to nude mice for 2-3 weeks induced development of T-cell function as determined by antibody response to a T-dependent antigen, and a response of spleen cells to T-cell mitogen.
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PMID:Biological activity of the pure thymus protein, LSHr. 11 61

DNA methylase has been purified 405-fold from Krebs II ascites cells. The purified enzyme is homogeneous on SDS-poly acrylamide gel electrophoresis (molecular weight about 80,000) and the only product of the reaction with DNA is 5-methyl cytosine. Both native and denatured DNA are methylated by the enzyme; with calf thymus DNA the double stranded form is the better substrate but the enzyme preferentially methylates single stranded E.coli DNA even in "native" preparations. Our results do not support a mechanism whereby the enzyme methylates DNA by binding irreversibly and "walking" along it. By measuring maximum levels of methylation of DNAs from different sources we have estimated the proportion of unmethylated sites present in them. Homologous ascites DNA can be methylated, but only to about 5% of the level of the best substrate, undermethylated mouse L929 cell DNA. DNA isolated from growing cells or tissues is a better substrate than DNA from normal liver or pancreas, or from stationary cells.
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PMID:DNA methylase: purification from ascites cells and the effect of various DNA substrates on its activity. 13 36

A combination of the C-gamma alumina adsorption technique of Lindberg, U. Skoog, L. 1970. Eur. J. Biochem. 13 326-335 with the traditional actin purification procedure (polymerization-depolymerization) yielded a simple method for the preparation of actin from fresh or acetone-dried thymus tissue. Actin obtained by this procedure from thymus was homogeneous and comigrated with skeletal actin in SDS gel electrophoresis. In isoelectric focusing it was shown to contain beta and gamma actin. Thymus actin polymerized poorly or not at all. It was native, however, as judged from its DN-ase I inhibiting activity which equalled that of skeletal actin. It also activated skeletal myosin ATP-ase but to a lesser extent than skeletal actin. On addition of HMM to thymus G actin, decorated filaments formed abundantly.
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PMID:Thymus actin: preparation and characterization. 16 Jan 79

The synthesis and processing of feline leukemia virus (FeLV) polypeptides were studied in a chronically infected feline thymus tumor cell line, F-422, which produces the Rickard strain of FeLV. Immune precipitation with antiserum to FeLV p30 and subsequent sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) were used to isolate intracellular FeLV p30 and possible precursor polypeptides. SDS-PAGE of immune precipitates from cells pulse-labeled for 2.5 min with [35S]methionin revealed the presence of a 60,000-dalton precursor polypeptide (Pp60) as well as a 30,000-dalton polypeptide. When cells were grown in the presence of the proline analogue L-azetidine-2-carboxylic acid, a 70,000-dalton precursor polypeptide (Pp70) was found in addition to Pp60 after a 2.5-min pulse. The cleavage of Pp60 could be partially inhibited by the general protease inhibitor phenyl methyl sulfonyl fluoride (PMSF). This partial inhibition was found to occur only if PMSF was present during pulse-labeling. Intracellular Pp70 and Pp60 and FeLV virion p70, p30, p15, p11, and p10 were subjected to tryptic peptide analysis. The results of this tryptic peptide analysis demonstrated that intracellular Pp70 and virion p70 were identical and that both contained the tryptic peptides of FeLV p30, p15, p11, and p10. Pp60 contained the tryptic peptides of FeLV P30, P15, and P10, but lacked the tryptic peptides of P11. The results of pactamycin gene ordering experiments indicated that the small structural proteins of FeLV are ordered p11-p15-p10-p30. The data indicate that the small structural proteins of FeLV are synthesized as part of a 70,000-dalton precursor. A cleavage scheme for the generation of FeLV p70, p30, p15, p11, and p10 from precursor polypeptides is proposed.
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PMID:Analysis of intracellular feline leukemia virus proteins II. Generation of feline leukemia virus structural proteins from precursor polypeptides. 19 17

Plasma membranes of splenic and thymic lymphocytes from ACI rats were analyzed for their protein and glycoprotein components by surface radioiodination with 125I and SDS-polyacrylamide gel electrophoresis. The glycoproteins were extracted with lithium diiodosalicylate, characterized and assayed with antisera to thymic antigen. Plasma membranes of both cell types showed more than 25 proteins of which 10--15 were glycoproteins. Both cells showed five major glycoproteins but their apparent molecular weights or intensities differed. Surface radioiodination showed a 120 000 daltons component, common to both cell types, and a 27 000 daltons thymus-specific component as the most exposed surface glycoproteins. Lithium diiodosalicylate extracts of the plasma membranes contained almost all of the glycoprotein components and comprised 5-6 percent of the total membrane protein and 40-50 percent of the total membrane carbohydrate, with sialic acid content in thymus twice that of the spleen cells. About 1 percent of the total plasma membrane protein and 7 percent of the total isolated glycoproteins from thymocytes were reactive with rabbit anti-rat thymocyte antiserum and the immune precipitates showed two components with apparent molecular weights of 72 000 and 27 000.
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PMID:Lymphocyte plasma membranes. VI. Plasma membrane glycoproteins of thymic and splenic lymphocytes from inbred rats. 30 61

An endonuclease that can act on calf thymus DNA and circular doublestranded phage PM2 DNA has been isolated from HeLa S3 cell chromatin. Approximately 200-fold purification was achieved by a sequence of subcellular fractionation, differential NaCl solubility and chromatography on CM-Sephadex, DEAE-cellulose and hydroxyapatite, and isoelectric point is pH 5.1 +/- 0.2. Divalent cations are necessary for its activity and the enzyme is heat inactivated at 60 degrees C. The enzyme activity is sensitive to caffeine and sulfhydryl reacting compounds. The molecular weight, determined by gel filtration and SDS gel electrophoresis, is approx. 22 000.
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PMID:Purification and properties of a nuclear DNA endonuclease from HeLa S3 cells. 44 34

The chromatin of shrimp hepatopancreas has been extracted from isolated nuclei and characterized. Nuclei were prepared in the presence of Cu++ and phenyl methyl sulfonyl fluoride in order to inhibit the nuclease and protease activities throughout the different purification steps. The purified nuclei are heterogenous in size and show a density of 1,367 g/ml determined on saccharose - glucose gradients. After washing in 0,14 M NaCl and then in 10(-2) M Tris-HCL, pH = 7,6, the nuclei were disrupted in water. The solubilized chromatin was precipitated in 0,15 M.NaCl. This chromatin is characterized by a high level of RNA (RNA/DNA = 0,38) and of non histone proteins (NHP/DNA = 0,6). The denaturation curve showed only one Tm at 69 degrees in 2.10(-4) M.EDTA. When the chromatin was extracted in the presence of staphylococcal nuclease, the Tm reached 80 degrees C. The kinetics of the digestion by the staphylococcal nuclease have been studied and show that 10 per cent of hydrolysis occurs within the first minute. The repeat length of DNA as determined with the polymers of higher order is 189 +/- 5 base pairs. The existence of nucleosomes was confirmed by electron microscopy. The superstructure of chromatin was not completely destroyed after solubilisation with a Potter. The histones were studied by gel electrophoresis after differential staining. The most important feature consists in the presence of two H1, two H2A and two H4. The acetylation levels of the histones were followed after injection of 14C-acetate in vivo. The subfraction H1, 0 was acetylated. Only one H3 was present and the two H2A fractions showed the same level of acetylation. H2B migrated faster than the H2A fractions like in Echinoderms. The two H4 fractions corresponded to two differently acetylated forms. Shrimp hepatopancreas histones were fractionated by molecular sieving on Biogel P 100 and characterized according to their electrophoretic properties as well as their amino-acid content. The amino-acid compositions of the different histone fractions were nearer to Echinoderm and Sipunculid histones, than Calf thymus homologue histones. All the fractions show a weaker basicity. The H3 fraction was the only one showing a lesser variability when compared to Calf thymus H3. The non histone proteins were extracted in 10(-2) M Tris-HCL, pH = 8 and 0.1 per cent SDS. A series of 50 proteins was detected. 80 per cent of the total amount of protein was localized in a molecular weight range comprised between 40 000 and 80 000 daltons. These proteins were compared to the histones and total proteins of sonicated chromatin solubilized by SDS in order to detect proteasic effects.
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PMID:[Characterization of histones and chromatin of the hepatopancreas in Palaemon serratus (Crustacea Natantia)]. 45 90


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