共查询到20条相似文献,搜索用时 31 毫秒
1.
Abstract Alpha-1 acid glycoprotein (or orosmucoid) was obtained in a pure state from normal human serum by ion exchange chromatography followed by curtain electrophoresis and a final ion exchange chromatography step. Pure α1 acid glycoprotein (α1A) has a sedimentation coefficient of 3.1 S and a diffusion coefficient of 5.2 × 10?7cm2 sec?1, which yields a molecular weight of 44,680 Daltons and an asymmetry factor of 14.6. The αA prepared in the manner here described appears less denatured than the same protein isolated by the Cohn fractionation method.1,2 ' Alpha-1 A acts as a depressant of phagocytosis3 and is one of the constituents of Mowbray's serum fraction,″which induces a prolongation of skin homografts. 相似文献
2.
K. M. Dziegielewska K. Møllgård M. L. Reynolds N. R. Saunders 《Cell and tissue research》1987,248(1):33-41
Summary The human plasma protein, 2HS glycoprotein, has an amino acid composition very similar to that of fetuin, the major protein in fetal calf and lamb serum. Immunohistochemical studies of human fetuses (6–33 weeks gestation) showed that 2HS glycoprotein and fetuin have similar distributions in developing brain and several other tissues, e.g., bone, kidney, gonads, gastrointestinal tract, respiratory and cardiovascular systems. There were notable differences in the liver and thymus in the distribution of the two proteins. Fetuin and 2HS glycoprotein are present in plasma and cerebrospinal fluid of both human and sheep fetuses; their concentrations are reciprocally related: in human plasma and cerebrospinal fluid 2HS glycoprotein concentration is high and fetuin low; the reverse is the case in sheep fetuses.Estimates of the concentration of 2HS glycoprotein in human fetal cerebrospinal fluid and plasma were obtained. It is suggested that 2HS glycoprotein may play a role in developing tissues, especially in the human fetus, similar to that of fetuin in other species. 相似文献
3.
F. A. von Bülow M. Stagaard Janas O. B. F. Terkelsen K. Møllgård 《Histochemistry and cell biology》1993,99(1):13-22
An immunohistochemical study was undertaken, in an attempt to identify the acidic glycoprotein(s) present in colloid and in parenchymal cells in human fetal pituitary gland. As the colloid has been proposed to represent disintegrating cells, a series of antibodies against plasma glycoproteins and plasma proteins was applied; their presence intracellularly would generally be an indicator of plasma membrane leakage in dying parenchymal cells. In tissue sections from 9- to 20-week-old fetuses, the colloid showed prominent staining with an antibody to human fetuin/2 HS glycoprotein. Anti-2-HS glycoprotein labelled parenchymal cells in pars anterior and intermedia. Apart from a minor immunoreactivity for 1 glycoprotein, no other plasma glycoprotein was seen in colloid or parenchymal cells. An antibody against bovine fetuin showed staining of the colloid and of some parenchymal cells in pars distalis and intermedia; the plasma and stroma of the pituitary gland were unstained. In contrast, the anti-human plasma protein antibodies all stained the stroma. The presence of 2 HS glycoprotein in parenchymal cells and absence of other plasma glycoproteins imply integrity of the parenchymal cell plasma membrane. Thus, 2 HS glycoprotein is either synthesized locally or taken up specifically in the parenchymal cells, which are proposed to participate in the formation of colloid. It is suggested that 2 HS glycoprotein is part of a homeostatic system, which controls remodelling and physiological cell death during development. 相似文献
4.
W J Hubbard 《Cellular immunology》1978,39(2):388-394
Alpha-2 macroglobulin (α2M)2 has been reported to be capable of suppressing the division and functions of immune system and other cell types. A hypothesis is proposed which explains this suppression on the basis of denatured α2M being the suppressor molecule and native state α2M having no such activity, thus reconciling how α2M could be present in an animal without depressing normal activities. Speculations are offered for α2M's role in feedback regulation of cell division and also for the subversion of this regulatory function by invasive organisms and tumors. 相似文献
5.
《Biochimica et Biophysica Acta.Protein Structure》1976,420(1):195-213
The nature of the steroid binding site in α1-acid glycoprotein (orosomucoid) was investigated by chemical modification of individual amino acids and subsequent examination of the binding affinity for progesterone. Equilibrium dialyses were performed under conditions that excluded contact with human skin. Reaction of the lysyl residues with trinitrobenzenesulfonic acid or arylisocyanates resulted in a reduction of active sites. In an alternate approach, one lysyl residue of α1-acid glycoprotein was protected from modification by trinitrobenzenesulfonic acid when progesterone was present to form the complex with α1-acid glycoprotein. We conclude that a lysyl residue is located in the binding site.Reaction of tetranitromethane with the tyrosine groups in α1-acid glycoprotein also reduced the number of active binding sites for progesterone. Again, a partial protection of this modification was seen in the presence of progesterone and other Δ4-3-ketosteroids. The progesterone binding activity observed in the tyrosine-modified α1-acid glycoprotein by equilibrium dialysis and by fluorescence quenching titration can be interpreted best by the presence of one tyrosyl residue in the binding site, and involvement of a second tyrosine nearby.Modification of tryptophan in α1-acid glycoprotein by mild acid hydrolysis, N-bromosuccinimide, hydroxynitrobenzylbromide, and formic acid resulted in a decreased steroid binding; the formylation reaction was fully reversible. The approximate distance between progesterone and the tryptophan involved in the binding was calculated to be between 9.1A˚and 14.1A˚.When α1-acid glycoprotein was cleaved by the cyanogen bromide procedure according to Ikenaka et al. (1972, Biochemistry 11, 3817–3829), both the amino and the car☐yl fragment had weak progesterone binding affinity which could be measured in 4 M NaCl. This result thus failed to specify the location of the steroid binding site in α1-acid glycoprotein. However, the closeness of tryptophan, lysine and tyrosine in the primary and presumably the tertiary structure of α1-acid glycoprotein is in agreement with the properties of the binding site suggested by our studies. 相似文献
6.
The terminal d-galactopyranosyl residues of asialoglycopeptides isolated from human α1-acid glycoprotein were oxidized in nearly quantitative yield to the corresponding uronic acid residues by a two-step sequence employing d-galactose oxidase followed by treatment with Tollens reagent, Ag(NH3)2+. Mild acid hydrolysis of the oxidized glycopeptides led to the isolation of the corresponding aldobiuronic acid(s). Structural and colorimetric analysis revealed that only one aldobiuronic acid, 2-amino-2-deoxy-4-O-(β-d-galactopyranosyluronic acid)-d-glucose, was isolated from the oxidized glycopeptides of α1-acid glycoprotein. This method can readily distinguish between the (1→3), (1→4), and (1→6) isomers of the corresponding aldobiuronic acids. 相似文献
7.
Extracellular protein misfolding is implicated in many age-related diseases including Alzheimer's disease, macular degeneration and arthritis. In this study, putative endogenous clients for the chaperone activity of α2-macroglobulin (α2M) were identified after human plasma was subjected to physiologically relevant sheer stress at 37 °C for 10 days. Western blot analysis showed that four major acute phase proteins: ceruloplasmin, fibrinogen, α1-acid glycoprotein and complement component 3, preferentially co-purified with α2M after plasma was stressed. Furthermore, the formation of complexes between α2M and these putative chaperone clients, detected by sandwich ELISA, was shown to be enhanced in response to stress. These results support the hypothesis that α2M plays an important role in extracellular proteostasis by sequestering misfolded proteins and targeting them for disposal, particularly during acute phase reactions. 相似文献
8.
K. M. Dziegielewska W. M. Brown C. C. Gould N. Matthews J. E. C. Sedgwick N. R. Saunders 《Journal of comparative physiology. B, Biochemical, systemic, and environmental physiology》1992,162(2):168-171
Summary Fetuin is a plasma protein present in high concentrations during fetal development in animals of the order Artiodactyla. Its role is not known. The human homologue of fetuin — 2HS glycoprotein — has been shown to be a negative acute phase protein in adult plasma. In the present study, the concentration of fetuin was measured in the serum of healthy cattle (Bovis bovis) and in animals with various injuries and inflammatory disorders. The levels were decreased by 30% in pregnancy but increased up to 10-fold in some trauma cases. A significant negative correlation between the concentrations of fetuin and albumin has also been found. Thus, fetuin appears to be a positive acute phase protein in cattle.Abbreviations 2HS
2HS glycoprotein
- AP
acute phase 相似文献
9.
Bernard Bayard Jean-Pierre Kerckaert 《Biochemical and biophysical research communications》1980,95(2):777-784
Pooled and alkylated α1-acid glycoprotein was fractionated on a Con A-Sepharose column into two fractions : Con A-non reactive and Con A-reactive. The carbohydrate moiety from the α1-acid glycoprotein Con A-reactive variant, obtained by hydrazinolysis and quantitative re-N-acetylation, contains only identical two-branched oligosaccharide chains. From the present work on α1-acid glycoprotein and from previous studies on α1-fetoprotein, one can assume that glycoprotein glycosylation occurs uniformly along each polypeptide chain giving it identical oligosaccharide units at each glycosylation site. 相似文献
10.
S. C. Lee K. N. Lee D. G. Schwartzott K. W. Jackson W.-C. Tae P. A. McKee 《Preparative biochemistry & biotechnology》2013,43(4):227-237
ABSTRACT α2-antiplasmin, a plasma glycoprotein of the serpin superfamily, is the primary physiological inhibitor of plasmin, the key enzyme in fibrin degradation. Previous purification methods utilize lengthy multistep protocols with low yields or use monoclonal antibodies that are expensive or difficult to make. With a relatively small investment, a chicken was immunized with keyhole limpet hemocyanin-conjugated to α2-antiplasmin C-terminal 26 residue synthetic peptide and the peptide-specific antibody (IgY) was isolated from the egg yolks of hens using the peptide affinity column. Based on the interaction between this IgY and α2-antiplasmin, pure α2-antiplasmin was isolated from human plasma in two steps: (a) citrated plasma was precipitated with 15% PEG-8000 to remove the bulk of plasma proteins while retaining the majority of α2-antiplasmin activity; and (b) the α2-antiplasmin was affinity-purified from the supernatant using the IgY column. Yields were typically 48% and the purity and authenticity of the α2-antiplasmin were verified by gel electrophoresis, Western Blot analysis, N-terminal sequence, and amino acid analysis. 相似文献
11.
Udayananth Aich Deanna C. Hurum Lipika Basumallick Srinivasa Rao Chris Pohl Jeffrey S. Rohrer Sebastian Kandzia 《Analytical biochemistry》2014
Labeling of released asparagine-linked (N-linked) oligosaccharides from glycoproteins is commonly performed to aid in the separation and detection of the oligosaccharide. Of the many available oligosaccharide labels, 2-amino benzamide (2-AB) is a popular choice for providing a fluorescent product. The derivatization conditions can potentially lead to oligosaccharide desialylation. This work evaluated the extent of sialic acid loss during 2-AB labeling of N-linked oligosaccharides released from bovine fetuin, polyclonal human serum immunoglobulin G (IgG), and human α1-acid glycoprotein (AGP) as well as of sialylated oligosaccharide reference standards and found that for more highly sialylated oligosaccharides the loss is greater than the <2% value commonly cited. Manufacturers of glycoprotein biotherapeutics need to produce products with a consistent state of sialylation and, therefore, require an accurate assessment of glycoprotein sialylation. 相似文献
12.
Zorica S. Mitić Zorica Stojanović-Radić Vladimir J. Cvetković Snežana Č. Jovanović Marina Dimitrijević Jovana D. Ickovski Nikola Jovanović Tatjana Mihajilov-Krstev Gordana S. Stojanović 《化学与生物多样性》2021,18(9):e2100424
The present article investigates the chemical composition of volatiles of essential oil (EO) and headspace (HS) fraction, as well as biological activities of EO obtained from needles with twigs of Pseudotsuga menziesii var. menziesii cultivated in Serbia. The major class of compounds was monoterpene hydrocarbons with α-terpinolene, sabinene and β-pinene (EO), and sabinene, α-terpinolene and β-pinene (HS) as the dominant volatiles. Tested EO exhibited mostly low antimicrobial potential against investigated strains (ATCC and respiratory isolates), where MICs ranged 1.25–20.00 mg/mL. Nevertheless, based on presented results, where antimicrobial testing was done for the first time on human respiratory system isolates, there is a potential of this EO to be used as an adjuvant in the treatment of human respiratory infections, especially those caused by Pseudomonas aeruginosa or Candida albicans strains. Regarding toxicological evaluation, EO showed moderate toxicity in Artemia salina toxicity bioassay (LC50=347.41, after 24 h) as well as week toxicity against Drosophila melanogaster with the ability only to moderately delay larval and pupal development. 相似文献
13.
Presence of Ornithine in the Urate-binding α<Subscript>1</Subscript>—<Subscript>2</Subscript>Globulin 总被引:1,自引:0,他引:1
THE urate-binding α1–α2 globulin has been isolated from human plasma in a highly purified state1. The protein was purified by DEAE-‘Sephadex’, ammonium sulphate precipitation and semi-preparative Polyacrylamide gel electrophoresis. The urate-binding α1–α2 globulin is a rod-shaped glycoprotein, containing 12.1% carbohydrate, with an isoelectric point of 4.6 and a molecular weight of 67,000 ± 4,000. Amino-acid analysis indicated an unknown basic compound which appeared as an extra peak just in front of lysine1. To identify this compound, high voltage paper electrophoresis has been carried out on a plate electrophoresis apparatus in pyridine-acetate buffer pH 3.5. A spot separated out corresponding to ornithine. Amino-acid analysis on a BC-200 automatic analyser (Bio-Cal Instruments Co., West Germany), with a 54 cm column at 55° C and with 0.35 M sodium citrate buffer, pH 5.28, as elution buffer at a flow-rate of 150 ml./h, showed that ornithine was present. The presence of ornithine in the protein hydrolysate was also verified by gas chromatography/mass spectrometry2. 相似文献
14.
Mustafa Calapoğlu Orhan Değer Fulya Balaban Nilufer Şahin Calapoğlu Yılmaz Bülbül Keith Burling 《Biochemical genetics》2009,47(1-2):33-41
Deficiency of alpha-1-antitrypsin (α1-AT, a major protease inhibitor controlling tissue degradation) is a genetic disorder transmitted in a codominant autosomal form. It has more than 100 genetically determined variants. This study attempted to determine the degree of association between serum α1-AT levels and phenotypes and to provide a strategy for reliable laboratory evaluation of deficiencies. The study group consisted of a 38-year-old male proband with clinical features of emphysema, his first-degree relatives, and healthy controls. Family history revealed a four-generation pedigree. Genomic DNA was isolated from peripheral blood leukocytes. Alpha-1-AT levels were determined from human serum by immunonephelometry. Phenotypes were determined by isoelectric focusing of blood samples. DNA sequences of coding exons were analyzed by the amplification DNA technique and direct sequencing. Inheritance and plasma levels of the ZZ, MM, M3S, and MZ phenotypes were confirmed by the family study. In the family members with deficiencies, plasma concentrations were 22.55% ± 5.15 (ZZ), 84.18% ± 5.18 (M3S), and 61.06% ± 7.15 (MZ) of the normal MM level. We found a close association between α1-AT level and genotype. A combination of genotyping, quantification, and phenotyping is the optimal strategy for the laboratory evaluation of α1-AT deficiency. 相似文献
15.
Yuzo Imaizumi Chiho Suzuki Yutaro Azuma Kojiro Matsumoto 《Biochemical and biophysical research communications》2009,382(3):604-382
Killer lectin-like receptors on natural killer cells mediate cytotoxicity through glycans on target cells including the sialyl Lewis X antigen (sLeX). We investigated whether NK group 2D (NKG2D) and CD94 can bind to sialylated N-linked glycans, using recombinant glutathione S-transferase-fused extracellular lectin-like domains of NKG2D (rNKG2Dlec) and CD94 (rCD94lec). Both rNKG2Dlec and rCD94lec bound to plates coated with high-sLeX-expressing transferrin secreted by HepG2 cells (HepTF). The binding of rNKG2Dlec and rCD94lec to HepTF was markedly suppressed by treatment of HepTF with neuraminidase and in the presence of N-acetylneuraminic acid. Moreover, rNKG2Dlec and rCD94lec bound to α2,3-sialylated human α1-acid glycoprotein (AGP) but not to α2,6-sialylated AGP. Mutagenesis revealed that 152Y of NKG2D and 144F and 160N of CD94 were critical for HepTF binding. This is the first report that NKG2D and CD94 bind to α2,3-sialylated but not to α2,6-sialylated multi-antennary N-glycans. 相似文献
16.
A cDNA clone of porcine alpha1 acid glycoprotein (α1AGP) has been isolated and sequenced. Sequence homologies between porcine, human, and rat indicate that porcine α1AGP is similar in structure to the rat and human proteins. RNA blots from days 40, 60, 80, and 110 fetal, newborn, and adult livers showed that α1AGP mRNA is relatively abundant throughout fetal development, particularly at the later stages and in the newborn; there is a rapid decline in abundance following birth. From birth to 3 days of age, there is a three- to four-fold decline in abundance, and α1AGP mRNA is approximately 100 times less abundant in the adult liver than in that of perinatal pigs. Southern blots showed that α1AGP is probably a single-copy gene. The isolation of a cloned cDNA for porcine α1AGP provides a tool to investigate the molecular mechanisms involved in the developmental regulation of the gene and to correlate changes in gene expression during development with fetal growth and well being. 相似文献
17.
《Journal of receptor and signal transduction research》2013,33(3-4):187-195
Abstractα2- and β-adrenergic receptors in human placental membranes have been investigated using the radioligands [3H]-RX 821002 and [3H]-dihydroalprenolol, respectively. The specific binding of the α2-adrenoceptor antagonist RX 821002 confirms the presence of an α2-adrenoceptor in the human placenta, which has been characterized previously with [3H]-rauwolscine. The major finding presented here is a correlation between the α2- and β-adrenergic receptor concentrations (r=0.765) in the human placenta at term. It is suggested that the α2/β adrenoceptor balance may play an important role in regulation of the vascular bed of the placenta. Determination of the α2/β ratio may help towards an understanding of the contractility of the placental vascular muscles. 相似文献
18.
E. Zenteno M. Ortega Z. Qin J. Montreuil H. Debray 《Preparative biochemistry & biotechnology》2013,43(3-4):175-183
Abstract Phytohemagglutinin from red kidney bean has been purified by affinity chromatography on a human α1-acid glycoprotein Sepha-rose 4B column. Further purification of the hemagglutinin's five isolectins was achieved on a Mono S column with an 86% protein recovery. Each sequentially eluted isolectin from the ion exchange column displayed either hemagglutinating or mitogenic activity. The main activity of each fraction was the result of the combination of varying proportions of the L and E subunits. 相似文献
19.
Akira Hara Akira Sakamoto Akira Kobayashi 《Bioscience, biotechnology, and biochemistry》2013,77(11):2287-2289
A series of dansyl-labeled glycosides with di-, tetra-, and hexasaccharides carrying the terminal N-acetyllactosamine (LacNAc) sequence were synthesized as acceptor substrates for α2,6- and α2,3-sialyltransferases. As an alternative design, dansyl-labeled LacNAc glycoside carrying a long-spacer linked glycan was engineered by replacement of the LacNAc or lactose units with an alkyl chain. In addition, we designed a dansyl-labeled bi-antennary LacNAc glycoside as an N-linked oligosaccharide mimetic, such as asialo-α1-acid glycoprotein. The kinetic parameters for the transfer reaction of synthesized dansyl-labeled glycosides by sialyltransferases were determined by the fluorescent HPLC method. The catalytic efficiencies (V max/K m) of acceptor substrates carrying the terminal LacNAc sequence with various length glycans in the array for α2,6- and α2,3-sialyltransferases decreased in a glycan length-dependent manner. Furthermore, of the acceptor substrates tested, dansyl-labeled bi-antennary LacNAc glycoside displayed the most favorable K m value for α2,6- and α2,3-sialyltransferases. 相似文献
20.
The protein binding of the enantiomers of gallopamil has been investigated in solutions of human serum albumin, α1-acid glycoprotein and serum. Over the range of concentrations attained after oral gallopamil administration, the binding of both enantiomers to albumin, α1-acid glycoprotein, and serum proteins was independent of gallopamil concentration. The binding to both human serum albumin (40 g/liter) [range of fraction bound (fb) R: 0.624 to 0.699; S: 0.502 to 0.605] and α1-acid glycoprotein (0.5 g/liter) (range of fb R: 0.530 to 0.718; S: 0.502 to 0.620) was stereoselective, favoring the (R)-enantiomer (predialysis gallopamil concentrations 2.5 to 10,000 ng/ml). When the enantiomers (predialysis gallopamil concentration 10 ng/ml) were studied separately in drug-free serum samples from six healthy volunteers the fraction of (S)-gallopamil bound (fb: 0.943 ± 0.016) was lower (P < 0.05) than that of (R)-gallopamil (fb: 0.960 ± 0.010). The serum protein binding of both (R)- and (S)-gallopamil was unaffected by their optical antipodes (fb R: 0.963 ± 0.011; S: 0.948 ± 0.015) indicating that at therapeutic concentrations a protein binding enantiomer–enantiomer interaction does not occur. The protein binding of (R)- and (S)-gallopamil ex vivo 2 h after single dose oral administration of 50 mg pseudoracemic gallopamil (fb R: 0.960 ± 0.010: predialysis [R] 6.9 to 35.3 ng/ml; S: 0.943 ± 0.016: predialysis [S] 9.5 to 30.7 ng/ml) was comparable to that observed in vitro in drug-free serum. Gallopamil metabolites formed during first-pass following oral administration, therefore, do not influence the protein binding of (R)- or (S)-gallopamil. © 1993 Wiley-Liss, Inc. 相似文献