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1.
Matrix metalloproteinases are secreted from different cells as inactive zymogens. For their activation in vitro organomercurials may be used, the presence of which, however, can falsify activity assays and modulate the effects of the proteases in subsequent investigations. Here, we demonstrate the binding of human matrix metalloproteinase 1 to a thiophilic resin (mercaptoethylquinazolinedione derivatized agarose) and take advantage of this thiophilic interaction for the purification of organomercurial activated matrix metalloproteinase 1 from the supernatant of a thyroid carcinoma cell line in connection with the simultaneous removal of the activator.  相似文献   

2.
We have used thiophilic and hydrophobic interaction chromatography in an attempt to obtain enriched human immunoglobulin G (IgG) subclasses from a therapeutic immunoglobulin preparation. Proteins were adsorbed on a thiophilic gel and on Phenyl-, Butyl-, or Octyl-Sepharose in 1 M ammonium sulphate. Elution with a decreasing salt gradient produced no marked subclass selectivity, except with Octyl-Sepharose, which yielded a poorly adsorbed fraction somewhat enriched in IgG2, representing ca. 20% of the total initial protein. Neither thiophilic nor hydrophobic interaction chromatography appear suitable for an efficient enrichment in subclasses, which all show a broad heterogeneity in their affinity for these columns. The influence of the starting salt concentration was also studied. With thiophilic gels, in the absence of ammonium sulphate, ca. 30% of the initial load was not adsorbed, and was found to be enriched in IgG2. At 2.5 and 5% ammonium sulphate, practically no adsorption occurred. At 7.5% ammonium sulphate, the non-adsorbed fraction was enriched in IgG3. With Phenyl-Sepharose, adsorption increased smoothly with the salt concentration. It is concluded that different forces come into play for adsorption on thiophilic gels at low and high salt concentration.  相似文献   

3.
Several thiophilic adsorbents with mercaptoheterocyclic ligands have been analyzed for their ability to bind human serum proteins in a salt-independent way. In contrast to 2-mercaptopyrimidine, 2-mercaptopyridine derived ligands show a group-selective binding of immunoglobulins and α2-macroglobulin, not only in the presence of high concentrations of sodium sulphate but in buffers with low ionic strength. The binding is restricted to thiophilic gels obtained by coupling 2-mercaptopyridine to a vinylsulphone-activated matrix and is not achieved on epichlorohydrin-activated gels. A novel thiophilic ligand based on mercaptonicotinic acid, containing a carboxylic group together with the thiophilic pattern of thioaromatic adsorbents, is demonstrated to be useful as an alternative purification scheme for antibodies.  相似文献   

4.
A comparative study was carried out to investigate the influence of different mouse antibody subclasses on the chromatographic behaviour on thiophilic supports. Cell-free supernatants from different mouse-mouse hybridoma cultures in a standard medium were purified on thiophilic agarose and Fractogel EMD TA. The adsorption capacities and purification factors were monitored under optimised adsorption conditions. The different isotypes did not differ significantly regarding capacity of the thiophilic matrix, but the purity of the eluted antibody fractions was significantly lower for the IgG2a subclass compared to all other murine antibodies. A significant copurification of proteins from cell culture supernatant with antibodies of the IgG2a subclass indicated a restriction in the universal nature of thiophilic interaction.  相似文献   

5.
本研究通过嗜硫色谱、Sephadex G-75、蓝胶和POROS HQ20离子交换色谱,从蕲蛇蛇毒中分离得到一种新组分AA-MP-I。该酶为分子量22.9kDa的单体蛋白,等电点为5.55,不含中性糖基,N端序列为STE-FQRYMEIVIVVDHSMVK,结果表明其为新型P-I型金属蛋白酶,对温度敏感,具有抗凝血活性,40℃下抗凝血活性最强,具有出血毒性,无磷脂酶A2活性。  相似文献   

6.
Immunoglobulins have been selected by their general affinity for adjacent sulfone-thioether sulfur groups as a useful model system for the characterization of thiophilic interaction chromatography. Mercaptoethanol coupled to divinylsulfone-activated agarose (thiophilic or T-gel) provided an affinity matrix for the efficient and reversible immobilization of the immunoglobulins. The adsorption/desorption process was investigated as a function of protein concentration, temperature, flow rate, and pH in different concentrations of ammonium sulfate. Immobilization of these proteins was (as a function of pH) found to be both dependent and independent of the adsorption-promoting effects of water-structure-forming salts. Buffer conditions are recommended for the selective adsorption of immunoglobulins from unfractionated human serum. These results indicate that thiophilic interaction chromatography provides a new and effective alternative for the immobilization and purification of immunoglobulins and other proteins under conditions known to preserve structure and biological activity.  相似文献   

7.
In order to assess the requirement for matrix metalloproteinases in neuronal regeneration, in vitro neurite outgrowth by chick dorsal root ganglionic neurons (DRGn) was examined within a reconstituted extracellular matrix. For these studies, cultured neurons were treated with a synthetic peptide inhibitor of metalloproteinases (spIMP), LMHKPRCGYPDVGG.spIMP inhibited all neuronal metalloproteinase activities in zymography and substrate-release assays and was used to examine the role of metalloproteinases in neurite outgrowth by DRGn. Cultures of dissociated DRGn rapidly extended neurites on planar extracellular matrix substrates and this rate of outgrowth was not affected by adding NGF or spIMP. In contrast, neurite extension within a three-dimensional gel of extracellular matrix increased nearly threefold after adding NGF. The NGF-induced neurite penetration was negated in the presence of spIMP but not by control peptide. Similar results were obtained using explanted dorsal root ganglia. These findings suggested that NGF-induced neurite outgrowth within an extracellular matrix involves metalloproteinase activity. Zymographic analysis of media conditioned by NGF-treated DRGn revealed a pair of gelatinolytic bands with apparent molecular masses 72 and 66 kDa, which comigrated as a single 66-kDa band after activation with an organomercurial agent. The gelatinase activities were calcium- and zinc-dependent and were absent from zymograms developed in the presence of spIMP, indicating that NGF-treated DRGn release and activate a 72-kDa metalloproteinase. Samples from DRGn cultures treated with low levels of NGF contained similar amounts of latent and activated metalloproteinase, while high levels of NGF induced an apparent increase in total metalloproteinase secretion and a substantially greater proportion of activated enzyme. Western blot analysis showed this metalloproteinase was immunologically similar to 72-kDa type IV collagenase and immunoassays revealed that this matrix metalloproteinase was increased threefold by high NGF. Furthermore, after high NGF treatment, DRGn media contained sixfold more metalloproteinase activity in assays of matrix degradation. In summary, these results indicate that NGF enhanced metalloproteinase-dependent neurite outgrowth of DRGn within a reconstituted extracellular matrix. Also, NGF increased the expression and activation of 72-kDa type IV collagenase, suggesting a role for this matrix-degrading metalloproteinase in neuronal regeneration.  相似文献   

8.
The gene coding for human collagenase-3 (CLG3), a recently described matrix metalloproteinase produced by breast carcinomas, has been localized by fluorescence in situ hybridization on chromosome 11q22.3. Physical mapping of an isolated YAC clone containing CLG3 has revealed that this gene is tightly linked to those encoding other matrix metalloproteinases, including fibroblast collagenase (CLG1), stromelysin-1 (STMY1), and stromelysin-2 (STMY2). Further mapping of this region using pulsed-field gel electrophoresis has shown that the CLG3 gene is localized to the telomeric side of the matrix metalloproteinase cluster, the relative order of the loci being centromere—STMY2—CLG1—STMY1—CLG3—telomere.  相似文献   

9.
Abstract: Under a tightly regulated expression mechanism, matrix metalloproteinases degrade extracellular matrix proteins and are though to play a role in injury repair and tumor metastasis in peripheral tissues. Little is known about the function of matrix metalloproteinases or agents that regulate their production in adult brain; however, it has been shown that the activity of a calcium-dependent metalloproteinase is elevated in Alzheimer's hippocampus. The goals of this study were to determine whether cultured rat astrocytes produce matrix metalloproteinases and to identify agents that regulate protease activity. Enriched astrocyte cultures were prepared from brains of 1-day-old rat pups, and experiments were performed 13 days later. Gelatinase activity in astrocyte conditioned medium was determined using zymography with gelatin copolymerized with acrylamide in the gel. Under basal conditions after a 24-h incubation, rat astrocytes produce gelatinases of 58 and 66 kDa. On stimulation of astrocytes with lipopolysaccharide, interleukin-1α or -β, or tumor necrosis factor-α for 24 h, a dose-dependent increase in the activity of the 58- and 66-kDa gelatinases and the induction of a 94-kDa gelatinase occurred. All three astrocyte-derived proteases showed maximal activity in the presence of millimolar levels of Ca2+, their activity was inhibited in the presence of 1,10-phenanthroline, and their proenzymes were cleaved and activated after incubation with p-aminophenylmercuric acetate. Using immunoblotting, immunopositive bands at the respective molecular sizes indicated that the 58-kDa gelatinase was gelatinase A (matrix metalloproteinase 2) and the 94-kDa activity was gelatinase B (matrix metalloproteinase 9). Induction of the 94-kDa gelatinase by lipopolysaccharide was not influenced when interleukin-1 receptor antagonist was included during the 24-h incubation period; however, the antagonist completely blocked interleukin-1β-induced 94-kDa activity and diminished the activity of the 58- and 66-kDa gelatinases. Dexamethasone inhibited both lipopolysaccharide and interleukin-1β stimulation of the 94-kDa gelatinase. These results indicate that cytokines regulate matrix metalloproteinase expression in cultured rat astrocytes. Because astrocytes become “activated” (are hypertrophic and express increased levels of glial fibrillary acidic protein) in the presence of several inflammatory cytokines, it is possible that these astrocyte-derived enzymes contribute to the activation process and may participate in tissue remodeling after brain injury.  相似文献   

10.
Thiophilic adsorption: a comparison of model protein behavior   总被引:3,自引:0,他引:3  
T W Hutchens  J Porath 《Biochemistry》1987,26(22):7199-7204
A newly recognized type of protein-ligand interaction phenomenon has resulted in the preparation of simple, nonionic, and highly specific gel derivatives for selective adsorption chromatography. The essential structure of the immobilized ligand can be represented as agarose-CH2CH2SO2CH2CH2SCH2CH2OH, which was prepared by using mercaptoethanol to derivatize [0.9-1.0 mmol (g of dry gel)-1] divinyl sulfone activated agarose (thiophilic or T-gel). Proteins interacting with this ligand are provisionally termed "thiophilic" to recognize their affinity for the definitive sulfone-thioether constituents. To better understand the experimental variables affecting adsorption efficiency and selectivity, several well-characterized proteins with diverse physicochemical features have been evaluated for thiophilic properties. Thiophilic interaction chromatography was investigated as a function of pH as well as the type and concentration of water-structure-forming salts required to promote adsorption. The model proteins characterized varied distinctly in their individual thiophilic affinities. At acidic pH values, a salt-independent adsorption process was observed. Furthermore, a minimum in the salt-promoted thiophilic adsorption tendency at pH 5-6 was found, with varying magnitude, for each of the model proteins evaluated. Recovery of adsorbed proteins routinely varied from 90% to 100%. There does not appear as yet to be any easily recognized physicochemical property associated with either thiophilic or nonthiophilic behavior. These results suggest that thiophilic interaction chromatography is a process that utilizes a previously unrecognized protein-ligand interaction mechanism. We suggest that salt allows the protein into close proximity with the sulfone-thioether group where short-range forces are effective.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

11.
Here we have investigated the ability of laminin-1 and specific laminin-1-derived synthetic peptides to stimulate neuronal cell matrix metalloproteinase secretion. Zymographic analysis of conditioned media from laminin-1-treated PC12 and NG108-15 cells revealed a 72-kDa matrix metalloproteinase which was not secreted by untreated cells. Laminin-1 α1 chain-derived synthetic peptides, AASIKVAVSADR (LAM-L) and RKRLQVQLSIRT (AG-73), also stimulated PC12 cell secretion of a 72-kDa matrix metalloproteinase. We further investigated the structural requirements of AG-73 for cell attachment, neurite outgrowth, and matrix metalloproteinase secretion using a series of AG-73 analogs that had single amino acids substituted with alanine. At the substrate levels tested, the AG-73 peptide promoted the adhesion of 67% of the PC12 cells and neurite outgrowth in 71% of the PC12 cells. Substitutions in any one of the amino acids within the central LQVQ sequence resulted in a large reduction in cell attachment whereas substitution in the carboxyl terminal proximal amino acids L, S, and R had little effect on attachment. Alanine substitution of any of the amino terminal proximal LQV amino acids and the carboxyl terminal L, I, and R residues resulted in a 65–91% reduction in neurite outgrowth. These data demonstrate that the sequence requirements for cell attachment and neurite outgrowth were not necessarily coupled but that the sequence requirements for neurite outgrowth and matrix metalloproteinase secretion were identical. We conclude that laminin-1 is able to stimulate neuronal cells to secrete a matrix metalloproteinase. Further, this study identifies the LQVXLXIR laminin-1 α1 globular domain peptide to be capable of stimulating both neurite outgrowth and matrix metalloproteinase secretion.  相似文献   

12.
Endometriosis is a chronic inflammatory disease that occurs due to the presence of endometrial tissue outside the uterine cavity. It affects from 5% to 10% of women of reproductive age. High levels of matrix metalloproteinase (especially MMP-9) have been observed in women suffering from endometriosis. Thus, the aim of this study was to investigate the naturally anti-inflammatory compounds available from an algal source that can target the MMP-9 by various in silico approaches. The target 1L6J (Crystal structure of human matrix metalloproteinase MMP-9) structure was retrieved from the PDB database. Five compounds such as Eckol, Sargafuran, Vitamin E, Docosahexaenoic acid, Fucoidan and Elagolix were selected based on ‘Lipinski’s rule of five’ using the PubChem database. The pharmacokinetics, ADMET properties and biological activity of these compounds were predicted computationally using databases such as PreADME, SWISS-ADME, pkCSM and PASS. Comparative analysis of the bioactive compounds with the target was performed by AutoDock 4.2.6. Using LigPlot v.2.2, the target residues interacting with the compounds were visualised in a 2D manner. Based on the results, Eckol exhibited the highest binding energy value of −7.82 kcal/mol, whereas the Elagolix (control drug) showed a binding energy of −4.88 kcal. We conclude that Eckol can be a potent inhibitor of target MMP-9 with least side effects when compared to the control drug. Hence, this compound can be effectively explored by further in vitro and in vivo studies to develop more effective treatments for Endometriosis.  相似文献   

13.
14.
A series of succinyl hydroxamates/bishydroxamates as well as a new structural type of matrix metalloproteinase (MMP)/bacterial protease (BP) inhibitors, incorporating iminodiacetic (IDA) hydroxamate/bishydroxamate moieties, has been synthesized and tested for interaction with four vertebrate proteases, MMP-1, MMP-2, MMP-8 and MMP-9, and a BP, the collagenase isolated from Clostridium histolyticum (ChC). The new derivatives generally showed inhibition constants in the range of 8-62 nM against the five proteases mentioned above.  相似文献   

15.
Using real-time polymerase chain reaction (RT-PCR), we measured mRNA amounts of matrix metalloproteinases (MMPs): MMP-1, MMP-2, MMP-9, and MMP-12 genes in psoriatic lesions and unaffected skin of the same patients. We observed significant (about 15-fold) increase in the expression level of matrix metalloproteinase MMP-1 and MMP-12 genes associated with psoriasis. The results of our studies of MMP gene expression in cultured primary human keratinocytes treated with interleukin (IL)-17 have shown upregulation of MMP gene expression both in cultured keratinocytes and in psoriatic skin lesions. Therefore, upregulation of MMP genes in the skin affected by psoriasis could result from IL-17 effects on skin cells.  相似文献   

16.
The osteoarthritis (OA) progression is now considered to be related to inflammation. Anemonin (ANE) is a small natural molecule extracted from various kinds of Chinese traditional herbs and has been shown to inhibiting inflammation response. In this study, we examined whether ANE could attenuate the progression of OA via suppression of IL‐1β/NF‐κB pathway activation. Destabilization of the medial meniscus (DMM) was performed in 10‐week‐old male C57BL/6J mice. ANE was then intra‐articularly injected into joint capsule for 8 and 12 weeks. Human articular chondrocytes and cartilage explants challenged with interleukin‐1β (IL‐1β) were treated with ANE. We found that ANE delayed articular cartilage degeneration in vitro and in vivo. In particular, proteoglycan loss and chondrocyte hypertrophy were significantly decreased in ANE ‐treated mice compared with vehicle‐treated mice. ANE decreased the expressions of matrix metalloproteinase‐13 (MMP13), A disintegrin and metalloproteinase with thrombospondin motifs 5 (ADAMTS5), collagen X (Col X) while increasing Aggrecan level in murine with DMM surgery. ANE treatment also attenuated proteoglycan loss in human cartilage explants treated with IL‐1β ex vivo. ANE is a potent protective molecule for OA; it delays OA progression by suppressing ECM loss and chondrocyte hypertrophy partially by suppressing IL‐1β/NF‐κB pathway activation.  相似文献   

17.

Background  

The cervical mucus plug (CMP) is a semi-solid structure with antibacterial properties positioned in the cervical canal during pregnancy. The CMP contains high concentrations of matrix metalloproteinase 8 and 9 (MMP-8, MMP-9) and tissue inhibitor of metalloproteinase 1 (TIMP-1). This indicates a potential to degrade extracellular matrix components depending on the balance between free non-complexed inhibitors and active enzymes.  相似文献   

18.
New thiophilic matrices and new procedures were used for the purification of immunoglobulins both from human serum and from hybridoma cell cultures containing fetal calf serum. A range of aromatic and heteroaromatic ligands containing hydroxyl or amino groups have been coupled to divinyl sulfone-activated agarose. The resulting affinity matrices have the general formula M-O-CH2-CH2-SO2-CH2-CH2-X-Y, where M is the agarose matrix, X is oxygen or nitrogen, and Y is an aromatic or heteroaromatic compound. Contrary to earlier expectations these matrices showed pronounced thiophilic binding patterns when tested for the selective binding of immunoglobulins from human serum. The binding is influenced by the structure of the aromatic part of the ligand, the ligand concentration, and the concentration and type of lyotropic salt. 2-Hydroxypyridine coupled to divinyl sulfone-activated agarose was used to purify murine monoclonal antibodies (IgG1 and IgM) from hybridoma cell cultures containing fetal calf serum. Compared to previous methods, significantly increased binding capacity (300-1500%) was obtained by using 1.0-1.2 M ammonium sulfate. Purity of the monoclonal antibody may be optimized for each individual clone by washing the column with either a low concentration of ammonium sulfate or polyethylene glycol before elution.  相似文献   

19.
20.
Epidermal growth factor (EGF) and structurally related peptides promote neuronal survival and the development of midbrain dopaminergic neurons; however, the regulation of their production has not been fully elucidated. In this study, we found that the treatment of striatal cells with dopamine agonists enhances EGF release both in vivo and in vitro. We prepared neuron-enriched and non-neuronal cell-enriched cultures from the striatum of rat embryos and challenged those with various neurotransmitters or dopamine receptor agonists. Dopamine and a dopamine D(1) -like receptor agonist (SKF38393) triggered EGF release from neuron-enriched cultures in a dose-dependent manner. A D(2) -like agonist (quinpirole) increased EGF release only from non-neuronal cell-enriched cultures. The EGF release from striatal neurons and non-neuronal cells was concomitant with ErbB1 phosphorylation and/or with the activation of a disintegrin and metalloproteinase and matrix metalloproteinase. The EGF release from neurons was attenuated by an a disintegrin and metalloproteinase/matrix metalloproteinase inhibitor, GM6001, and a calcium ion chelator, BAPTA/AM. Transfection of cultured striatal neurons with alkaline phosphatase-tagged EGF precursor cDNA confirmed that dopamine D(1) -like receptor stimulation promoted both ectodomain shedding of the precursor and EGF release. Therefore, the activation of striatal dopamine receptors induces shedding and release of EGF to provide a retrograde neurotrophic signal to midbrain dopaminergic neurons.  相似文献   

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