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Tu YY, Chen CC, Chang JH, Chang HM. Characterization of Lactoferrin (LF) from Colostral Whey Using Anti-LF Antibody Immunoaffinity Chromatography. J Food Sci 2002. [DOI: 10.1111/j.1365-2621.2002.tb09442.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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2
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Lögdberg LE, Akerström B, Badve S. Tissue distribution of the lipocalin alpha-1 microglobulin in the developing human fetus. J Histochem Cytochem 2000; 48:1545-52. [PMID: 11036097 DOI: 10.1177/002215540004801111] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Abstract
Alpha-1 microglobulin (alpha(1)m), a lipocalin, is an evolutionarily conserved immunomodulatory plasma protein. In all species studied, alpha(1)m is synthesized by hepatocytes and catabolized in the renal proximal tubular cells. alpha(1)m deficiency has not been reported in any species, suggesting that its absence is lethal and indicating an important physiological role for this protein To clarify its functional role, tissue distribution studies are crucial. Such studies in humans have been restricted largely to adult fresh/frozen tissue. Formalin-fixed, paraffin-embedded multi-organ block tissue from aborted fetuses (gestational age range 7-22 weeks) was immunohistochemically examined for alpha(1)m reactivity. Moderate to strong reactivity was seen at all ages in hepatocytes, renal proximal tubule cells, and a subset of pancreatic islet cells. Muscle (cardiac, skeletal, or smooth), adrenal cortex, a scattered subset of intestinal mucosal cells, tips of small intestinal villi, and Leydig cells showed weaker and/or variable levels of reactivity. Connective tissue stained with variable location and intensity. The following cells/sites were consistently negative: thymus, spleen, hematopoietic cells, lung parenchyma, glomeruli, exocrine pancreas, epidermis, cartilage/bone, ovary, seminiferous tubules, epididymis, thyroid, and parathyroid. The results underscore the dominant role of liver and kidney in fetal alpha(1)m metabolism and provide a framework for understanding the functional role of this immunoregulatory protein.
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Affiliation(s)
- L E Lögdberg
- Department of Pathology, Albert Einstein College of Medicine & Montefiore Medical Center, Bronx, New York, USA.
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3
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Chen CC, Tu YY, Chang HM. Thermal Stability of Bovine Milk Immunoglobulin G (IgG) and the Effect of Added Thermal Protectants on the Stability. J Food Sci 2000. [DOI: 10.1111/j.1365-2621.2000.tb15977.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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4
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Osterlund T, Danielsson B, Degerman E, Contreras JA, Edgren G, Davis RC, Schotz MC, Holm C. Domain-structure analysis of recombinant rat hormone-sensitive lipase. Biochem J 1996; 319 ( Pt 2):411-20. [PMID: 8912675 PMCID: PMC1217784 DOI: 10.1042/bj3190411] [Citation(s) in RCA: 119] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
Hormone-sensitive lipase (HSL) plays a key role in lipid metabolism and overall energy homoeostasis, by controlling the release of fatty acids from stored triglycerides in adipose tissue. Lipases and esterases form a protein superfamily with a common structural fold, called the alpha/beta-hydrolase fold, and a catalytic triad of serine, aspartic or glutamic acid and histidine. Previous alignments between HSL and lipase 2 of Moraxella TA144 have been extended to cover a much larger part of the HSL sequence. From these extended alignments, possible sites for the catalytic triad and alpha/beta-hydrolase fold are suggested. Furthermore, it is proposed that HSL contains a structural domain with catalytic capacity and a regulatory module attached, as well as a structural N-terminal domain unique to this enzyme. In order to test the proposed domain structure, rat HSL was overexpressed and purified to homogeneity using a baculovirus/insect-cell expression system. The purification, resulting in > 99% purity, involved detergent solubilization followed by anion-exchange chromatography and hydrophobic-interaction chromatography. The purified recombinant enzyme was identical to rat adipose-tissue HSL with regard to specific activity, substrate specificity and ability to serve as a substrate for cAMP-dependent protein kinase. The recombinant HSL was subjected to denaturation by guanidine hydrochloride and limited proteolysis. These treatments resulted in more extensive loss of activity against phospholipid-stabilized lipid substrates than against water-soluble substrates, suggesting that the hydrolytic activity can be separated from recognition of lipid substrates. These data support the concept that HSL has at least two major domains.
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Affiliation(s)
- T Osterlund
- Section for Molecular Signalling, Lund University, Sweden
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5
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Jones C, Patel A, Griffin S, Martin J, Young P, O'Donnell K, Silverman C, Porter T, Chaiken I. Current trends in molecular recognition and bioseparation. J Chromatogr A 1995; 707:3-22. [PMID: 7633593 DOI: 10.1016/0021-9673(95)00466-z] [Citation(s) in RCA: 54] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Molecular recognition guides the selective interaction of macromolecules with each other in essentially all biological processes. Perhaps the most impactful use of biomolecular recognition in separation science has been in affinity chromatography. The results of the last 26 years, since Cuatrecases, Wilchek and Anfinsen first reported the purification of staphylococcal nuclease, have validated the power of biomolecular specificity for purification. This power has stimulated an explosion of solid-phase ligand designs and affinity chromatographic applications. An ongoing case in point is the purification of recombinant proteins, which has been aided by engineering the proteins to contain Affinity-Tag sequences, such as hexa-histidine for metal-chelate separation and epitope sequence for separation by an immobilized monoclonal antibody. Tag technology can be adapted for plate assays and other solid-phase techniques. The advance of affinity chromatography also has stimulated immobilized ligand-based methods to characterize macromolecular recognition, including both chromatographic and optical biosensor methods. And, new methods such as phage display and other diversity library approaches continue to emerge to identify new recognition molecules of potential use as affinity ligands. Overall, it is tantalizing to envision a continued evolution of new affinity technologies which use the selectivity built into biomolecular recognition as a vehicle for purification, analysis, screening and other applications in separation sciences.
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Affiliation(s)
- C Jones
- Department of Protein Biochemistry, SmithKline Beecham, King of Prussia, PA 19406, USA
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6
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Holst LS, Hoffmann AM, Mulder H, Sundler F, Holm C, Bergh A, Fredrikson G. Localization of hormone-sensitive lipase to rat Sertoli cells and its expression in developing and degenerating testes. FEBS Lett 1994; 355:125-30. [PMID: 7982484 DOI: 10.1016/0014-5793(94)01185-0] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023]
Abstract
Using in situ hybridization, hormone-sensitive lipase was found to be expressed in a stage-dependent manner in Sertoli cells of rat testis. No expression was found in Leydig cells but expression in spermatids could not be excluded. These results suggest a role for hormone-sensitive lipase in the metabolism of lipid droplets in Sertoli cells, in contrast to its previously proposed function in steroid biosynthesis. The expression of testicular hormone-sensitive lipase mRNA and protein, both larger in size compared to other tissues, coincided with the onset of spermatogenesis and was dependent on scrotal localization of the testis, suggesting a temperature-dependent, pretranslational regulation of expression.
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Affiliation(s)
- L S Holst
- Department of Medical and Physiological Chemistry, Lund University, Sweden
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7
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Bratt T, Cedervall T, Akerström B. Processing and secretion of rat alpha 1-microglobulin-bikunin expressed in eukaryotic cell lines. FEBS Lett 1994; 354:57-61. [PMID: 7525349 DOI: 10.1016/0014-5793(94)01087-0] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The precursor protein alpha 1-microglobulin-bikunin was cleaved to the same degree whether expressed in CHO cells or in mutated CHO cells, RPE.40 cells, suggested to lack a functional form of the intracellular protease furin. Thus, alpha 1-microglobulin-bikunin probably is not cleaved in vivo by furin. However, simultaneous overexpression of the precursor and furin in COS, CHO and RPE.40 cells increased the cleavage, suggesting that compartmentalisation and concentrations of protease and precursor are important for the cleavage, besides the in vitro specificity. Expression of alpha 1-microglobulin and bikunin alone gave different protein patterns of SDS-PAGE as compared to expression of the precursor and subsequent cleavage, suggesting that the precursor protein is important for the post-translational handling of alpha 1-microglobulin and bikunin.
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Affiliation(s)
- T Bratt
- Department of Medical and Physiological Chemistry, Lund University, Sweden
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8
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Holm C, Davis RC, Osterlund T, Schotz MC, Fredrikson G. Identification of the active site serine of hormone-sensitive lipase by site-directed mutagenesis. FEBS Lett 1994; 344:234-8. [PMID: 8187891 DOI: 10.1016/0014-5793(94)00403-x] [Citation(s) in RCA: 48] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The consensus pentapeptide GXSXG is found in virtually all lipases/esterases and generally contains the active site serine. The primary sequence of hormone-sensitive lipase contains a single copy of this pentapeptide, surrounding Ser-423. We have analyzed the catalytic role of Ser-423 by site-directed mutagenesis and expression of the mutant hormone-sensitive lipase in COS cells. Substitution of Ser-423 by several different amino acids resulted in the complete abolition of both lipase and esterase activity, whereas mutation of other conserved serine residues had no effect on the catalytic activity. These results strongly suggest that Ser-423 is the active site serine of hormone-sensitive lipase.
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Affiliation(s)
- C Holm
- Department of Medical and Physiological Chemistry, Lund University, Sweden
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9
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10
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Bratt T, Olsson H, Sjöberg EM, Jergil B, Akerström B. Cleavage of the alpha 1-microglobulin-bikunin precursor is localized to the Golgi apparatus of rat liver cells. BIOCHIMICA ET BIOPHYSICA ACTA 1993; 1157:147-54. [PMID: 7685189 DOI: 10.1016/0304-4165(93)90058-g] [Citation(s) in RCA: 57] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
alpha 1-Microglobulin, a plasma protein with immunoregulatory properties, and bikunin, the light chain of the proteinase inhibitors inter-alpha-inhibitor and pre-alpha-inhibitor, are translated as a precursor protein from the same mRNA. The cosynthesis of alpha 1-microglobulin and bikunin is unique compared to other proproteins such as procomplement components and prohormones, since alpha 1-microglobulin and bikunin have no known functional connection. Different forms of intracellular rat liver alpha 1-microglobulin were isolated and characterized by amino acid sequence analysis, lectin binding and glycosidase treatment. Their subcellular distribution was studied by Nycodenz and sucrose gradient centrifugation, pulse-chase experiments, and electrophoresis with subsequent immunoblotting, using pro-C3 and prohaptoglobin as reference proteins. Two alpha 1-microglobulin-bikunin precursors (40 and 42 kDa), containing one and two N-linked oligosaccharides, respectively, were detected in the endoplasmic reticulum. After transport to the Golgi apparatus, the precursors were cleaved, probably C-terminal to the sequence Arg-Ala-Arg-Arg immediately preceding the bikunin part, yielding free sialylated 28 kDa alpha 1-microglobulin, representing the mature protein. The cleavage was almost complete in phosphatidylinositol 4-kinase-enriched membranes, previously identified as a post-Golgi compartment. A fourth intracellular form of alpha 1-microglobulin, 26 kDa, lacked sialic acid. None of the intracellular forms carried the yellow-brown chromophore associated with alpha 1-microglobulin when purified from serum and urine, suggesting that this chromophore becomes linked to the protein after its secretion from the liver cells.
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Affiliation(s)
- T Bratt
- Department of Medical and Physiological Chemistry, University of Lund, Sweden
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11
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Detection of hormone-sensitive lipase in various tissues. I. Expression of an HSL/bacterial fusion protein and generation of anti-HSL antibodies. J Lipid Res 1993. [DOI: 10.1016/s0022-2275(20)39990-9] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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12
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Pei R, Arjomand-Shamsai M, Deng CT, Cesbron A, Bignon JD, Lee JH. A monospecific HLA-B27 fluorescein isothiocyanate-conjugated monoclonal antibody for rapid, simple and accurate HLA-B27 typing. TISSUE ANTIGENS 1993; 41:200-3. [PMID: 8362412 DOI: 10.1111/j.1399-0039.1993.tb02003.x] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Affiliation(s)
- R Pei
- Department of Research, One Lambda Inc., Canoga Park
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13
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Pierzchalski P, Rokita H, Koj A, Fries E, Akerström B. Synthesis of alpha 1-microglobulin in cultured rat hepatocytes is stimulated by interleukin-6, leukemia inhibitory factor, dexamethasone and retinoic acid. FEBS Lett 1992; 298:165-8. [PMID: 1371972 DOI: 10.1016/0014-5793(92)80047-k] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
The secretion of alpha 1-microglobulin by primary cultures of rat hepatocytes was found to increase upon the addition of interleukin-6 or leukemia inhibitory factor, two mediators of acute phase response. This stimulatory effect was further enhanced by dexamethasone. alpha 1-Microglobulin is synthesized as a precursor also containing bikunin, and the precursor protein is cleaved shortly before secretion. Our results therefore suggest that both alpha 1-microglobulin and bikunin are acute phase reactants in rat hepatocytes. Furthermore, we found that retinoic acid, previously shown to be involved in the regulation of cell differentiation and development, also stimulated alpha 1-microglobulin synthesis. Only free, uncomplexed alpha 1-microglobulin (28,000 Da) was detected in the hepatocyte media, suggesting that the complex between alpha 1-microglobulin and alpha 1-inhibitor 3, found in rat serum, is formed outside the hepatocyte.
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Affiliation(s)
- P Pierzchalski
- Institute of Molecular Biology, Jagiellonian University, Krakow, Poland
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14
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Kawakami H, Tanaka M, Tatsumi K, Dosako S. Effects of ionic strength and pH on the thermostability of lactoferrin. Int Dairy J 1992. [DOI: 10.1016/0958-6946(92)90033-i] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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15
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Abstract
Monoclonal antibodies were generated against purified bovine beta-lactoglobulin A. Six antibodies reactive only with beta-lactoglobulin were selected. At least one of the antibodies appeared to be species monospecific for bovine beta-lactoglobulin. The remaining five antibodies recognized proteins in caprine and porcine whey fractions. One monoclonal antibody (59-1) exhibited a distinct 2:1 preference for beta-lactoglobulin B over A at near neutral pH (7.5). These antibodies should prove extremely useful adjuncts in structural studies of bovine beta-lactoglobulin.
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Affiliation(s)
- K M Kuzmanoff
- Specialized Center for Cancer Research and Education, University of Illinois School of Medicine, Chicago 60612
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16
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Babiker-Mohamed H, Forsberg M, Olsson ML, Winquist O, Nilson BH, Lögdberg L, Akerström B. Characterization of monoclonal anti-alpha 1-microglobulin antibodies: binding strength, binding sites, and inhibition of lymphocyte stimulation. Scand J Immunol 1991; 34:655-66. [PMID: 1719614 DOI: 10.1111/j.1365-3083.1991.tb01589.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Eleven monoclonal antibodies (MoAb) directed against the immunoregulatory plasma glycoprotein alpha 1-microglobulin were characterized. The MoAb were produced in mice immunized with a mixture of alpha 1-microglobulin homologues from man, guinea pig, rat and rabbit. Using radioimmunoassay, western blotting, affinity chromatography, and Scatchard analysis, the affinities and binding sites of the MoAb were analysed. All antibodies were more or less cross-reactive, but most showed a major specificity for one or two of the alpha 1-microglobulin homologues. None of the antibodies was directed against the carbohydrate moiety of alpha 1-microglobulin. Six of the MoAb had high affinity for the antigen and four of these were directed towards the same part of the molecule though differing in their species specificity. Five showed lower affinity for the antigen and were mainly directed towards epitopes on other parts of the molecule. Only some of the antibodies could block the proliferation of lymphocytes induced by human alpha 1-microglobulin. The blocking efficiency of the different antibodies was similar when tested on the stimulation of human or mouse lymphocytes, suggesting that the same part of the alpha 1-microglobulin molecule is responsible in both species. The magnitude of blocking by the different MoAb was not related to their affinities, emphasizing the importance of where on the alpha 1-microglobulin molecule, rather than how strongly, they bind. The binding of the strongest blocking antibody was shown to be directed to a C-terminal peptide of rat alpha 1-microglobulin, indicating that this part of alpha 1-microglobulin is important for the mitogenic effects. Thus the panel of anti-alpha 1-microglobulin MoAb should be a valuable tool for structural and functional studies of alpha 1-microglobulin.
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Affiliation(s)
- H Babiker-Mohamed
- Department of Medical and Physiological Chemistry, University of Lund, Sweden
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17
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Holm C, Davis RC, Fredrikson G, Belfrage P, Schotz MC. Expression of biologically active hormone-sensitive lipase in mammalian (COS) cells. FEBS Lett 1991; 285:139-44. [PMID: 1648510 DOI: 10.1016/0014-5793(91)80744-n] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
cDNAs encoding rat adipose tissue hormone-sensitive lipase were expressed in COS cells, under the control of the SV40 promoter to half the level in rat adipocytes, the richest native source of the enzyme. A cDNA lacking most of the long 5'-untranslated region of the full-length rat hormone-sensitive lipase cDNA was, with regard to the lipase activity, on the average 70% more efficiently expressed that the full-length cDNA. The recombinant protein was almost identical to hormone-sensitive lipase of rat adipose tissue with respect to specific activity, susceptibility to inhibitors, molecular size, phosphorylation and activation by cyclic AMP-dependent protein kinase. The described eukaryotic expression system will allow analysis of effects of amino acid substitutions introduced into the lipase molecule by site-directed mutagenesis.
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Affiliation(s)
- C Holm
- Department of Medical and Physiological Chemistry 4, University of Lund, Sweden
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18
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Abstract
A cell surface receptor that binds to the Fc region of IgA is expressed by certain strains of group A streptococci. The physico-chemical properties and binding characteristics of this receptor, called protein Arp, were studied. Like bacterial receptors that bind IgG, protein Arp has an elongated shape and no disulfide bonds. The affinity constant of protein Arp for three different molecular forms of IgA was determined, and was found to be more than ten-fold higher for serum IgA than for two complexed forms of IgA: secretory IgA and IgA bound to alpha 1-microglobulin. Cleavage of protein Arp with CNBr resulted in a peptide corresponding to the region located outside the cell wall, except for the N-terminal 52 amino acids. This CNBr-fragment did not bind IgA, which strongly suggests that the IgA-binding region of protein Arp is located in the N-terminal part of the molecule. In addition to the binding of IgA, protein Arp also binds to IgG weakly. The pH-dependence of these two types of binding is different, with maximal binding of IgA at neutral pH (5-7) and maximal binding of IgG at acidic pH (3-5). Both for IgA and IgG, protein Arp shows strong specificity for immunoglobulins of human origin.
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Affiliation(s)
- B Akerström
- Department of Medical and Physiological Chemistry, University of Lund, Sweden
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19
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Assays for Biosynthesis of Thyrotropin-Releasing Hormone. ACTA ACUST UNITED AC 1991. [DOI: 10.1016/b978-0-12-185261-0.50009-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register]
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20
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Falkenberg C, Grubb A, Akerström B. Isolation of rat serum alpha 1-microglobulin. Identification of a complex with alpha 1-inhibitor-3, a rat alpha 2-macroglobulin homologue. J Biol Chem 1990. [DOI: 10.1016/s0021-9258(17)46201-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022] Open
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21
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Holm C, Belfrage P, Fredrikson G. Human adipose tissue hormone-sensitive lipase: identification and comparison with other species. BIOCHIMICA ET BIOPHYSICA ACTA 1989; 1006:193-7. [PMID: 2557074 DOI: 10.1016/0005-2760(89)90195-1] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
The mRNA for human hormone-sensitive lipase (HSL) was identified using Northern blot analysis and a cDNA-probe for rat HSL. As in the rat, human adipose tissue expresses a single mRNA species of 3.3 kb. Using Western blotting with a polyclonal rabbit antibody towards rat adipose tissue HSL, the corresponding enzyme in human adipose tissue was identified with an apparent 88 kDa polypeptide, thus slightly larger than the rat and bovine 84 kDa, and the mouse and guinea-pig 82 kDa species. Additional evidence for the identification was provided by the inhibition of HSL diacylglycerol lipase activity by the anti-rat HSL antibody, and by NaF, DFP and Hg2+, known inhibitors of HSL. The concentration of the enzyme, as reflected by its activity per g tissue and the specific activity was about two thirds of that in the rat adipose tissue (200 g rats). The identification of the human enzyme protein made it possible to directly demonstrate its phosphorylation by cAMP-dependent protein kinase, thus extending the previous report regarding activation of the lipase with this kinase and ATP-Mg2+ in human adipose tissue extracts (Khoo, J.C., Aquino, A.A. and Steinberg, D. (1974) J. Clin. Invest. 53, 1124-1131).
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Affiliation(s)
- C Holm
- Department of Medical and Physiological Chemistry 4, University of Lund, Sweden
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22
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Nilsson S, Holm C, Belfrage P. Rapid purification of detergent-solubilized bovine hormone-sensitive lipase by high performance hydrophobic interaction chromatography. Biomed Chromatogr 1989; 3:82-7. [PMID: 2472185 DOI: 10.1002/bmc.1130030210] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Hormone-sensitive lipase (HSL), the enzyme controlling the rate of adipose tissue lipolysis and also possibly involved in the regulation of steroidogenesis, has been purified from bovine omental adipose tissue. Partially detergent-solubilized, delipidated and purified HSL was obtained through step-elution at conventional DEAE ion-exchange chromatography, followed by concentration on hydroxylapatite. High performance hydrophobic interaction chromatography (HPHIC) on phenylsilica then resulted in an increase of HSL protein purity from 2% to more than 70%. Final purification of the enzyme to apparent homogeneity (greater than 95% protein purity), concentration and removal of most of the detergent was obtained by high performance cation exchange chromatography on Mono S. At least 0.5 mg of highly stable HSL was obtained from 5 kg of bovine omental fat within four working days. The purified lipase had a lower specific activity than previously reported for the corresponding rat enzyme but the preparations have proved very useful for enzyme structure studies and as an antigen.
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Affiliation(s)
- S Nilsson
- Department of Medical and Physiological Chemistry, University of Lund, Sweden
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23
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Holm C, Kirchgessner TG, Svenson KL, Fredrikson G, Nilsson S, Miller CG, Shively JE, Heinzmann C, Sparkes RS, Mohandas T. Hormone-sensitive lipase: sequence, expression, and chromosomal localization to 19 cent-q13.3. Science 1988; 241:1503-6. [PMID: 3420405 DOI: 10.1126/science.3420405] [Citation(s) in RCA: 249] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Hormone-sensitive lipase, a key enzyme in fatty acid mobilization, overall energy homeostasis, and possibly steroidogenesis, is acutely controlled through reversible phosphorylation by catecholamines and insulin. The 757-amino acid sequence predicted from a cloned rat adipocyte complementary DNA showed no homology with any other known lipase or protein. The activity-controlling phosphorylation site was localized to Ser563 in a markedly hydrophilic domain, and a lipid-binding consensus site was tentatively identified. One or several messenger RNA species (3.3, 3.5, or 3.9 kilobases) were expressed in adipose and steroidogenic tissues and heart and skeletal muscle. The human hormone-sensitive lipase gene mapped to chromosome 19 cent-q13.3.
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Affiliation(s)
- C Holm
- Department of Medical and Physiological Chemistry, University of Lund, Sweden
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24
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Nilson B, Björck L, Akerström B. Enzyme linked immunosorbent assay using alkaline phosphatase conjugated with streptococcal protein G. JOURNAL OF IMMUNOASSAY 1988; 9:207-25. [PMID: 3372703 DOI: 10.1080/15321818808057041] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Protein G, an IgG-binding protein, purified from the surface of group G streptococci, was coupled to alkaline phosphatase. The conjugate was used for detection of polyclonal goat and rabbit antibodies and monoclonal mouse IgG1, IgG2a and IgG2b in an enzyme-linked immunosorbent assay. A two-step coupling procedure was used, in which glutaraldehyde was allowed to react with the enzyme, excess glutaraldehyde was then removed by dialysis, and finally protein G added to the glutaraldehyde-activated and polymerized alkaline phosphatase. The activity and yield of the conjugates were then tested in an enzyme-linked immunosorbent assay. Coupling of 25 micrograms protein G to 5 mg alkaline phosphatase gave a conjugate which could be used for more than 10,000 determinations with maximal antibody binding giving an absorbance of 2.0. Under these conditions, there was no need for separation of the reactants before using the protein G-alkaline phosphatase complex.
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Affiliation(s)
- B Nilson
- Department of Physiological Chemistry, University of Lund, Sweden
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25
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Holm C, Fredrikson G, Cannon B, Belfrage P. Hormone-sensitive lipase in brown adipose tissue: identification and effect of cold exposure. Biosci Rep 1987; 7:897-904. [PMID: 3329536 DOI: 10.1007/bf01119481] [Citation(s) in RCA: 31] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023] Open
Abstract
Hormone-sensitive lipase (HSL) in brown adipose tissue from mice was identified through immunoprecipitation with a polyclonal antibody (anti-HSL) towards rat white fat HSL and Western blotting. An 82 kDa polypeptide, slightly smaller than the rat white fat HSL 84 kDa subunit, was detected and its identity as HSL verified by inhibition properties. The HSL concentration per g tissue was several-fold higher in the mouse brown adipose tissue than in the rat white adipose tissue, but the specific activities per mg protein were similar. Cold-exposure (4 degrees C) of the mice for 24 h approximately doubled the HSL concentration but this increase parallelled the overall protein increase and did not reflect a specific effect on the HSL.
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Affiliation(s)
- C Holm
- Department of Medical and Physiological Chemistry, University of Lund, Sweden
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Holm C, Belfrage P, Fredrikson G. Immunological evidence for the presence of hormone-sensitive lipase in rat tissues other than adipose tissue. Biochem Biophys Res Commun 1987; 148:99-105. [PMID: 3675597 DOI: 10.1016/0006-291x(87)91081-3] [Citation(s) in RCA: 128] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
A polyclonal rabbit antibody was used to detect hormone-sensitive lipase in rat organs other than white adipose tissue. Inhibition of tissue diacylglycerol lipase activity by the anti-hormone-sensitive lipase, and by NaF, Hg2+ and diisopropyl fluorophosphate, known inhibitors of the hormone-sensitive lipase, demonstrated its presence in the adrenals, ovaries, testes, heart and skeletal muscle, but not in the liver and kidneys. After enrichment by immunoprecipitation an immunoreactive protein, corresponding to the adipose tissue hormone-sensitive lipase 84 kDa subunit, and some additional, higher Mrapp proteins, were detected by Western blotting in the same tissues. The adipose tissue contained greater than 80% of the total hormone-sensitive lipase, with 5-10- and 50-100-fold lower specific activity in the steroid-producing and the muscle tissues, respectively.
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Affiliation(s)
- C Holm
- Department of Medical and Physiological Chemistry 4, University of Lund, Sweden
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