Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound   Target Concepts: Gene/Protein Disease Symptom Drug Enzyme Compound

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Query: EC:3.1.27.1 (RNase)
16,360 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The new small-scale cross-axis coil planet centrifuge (X-axis CPC) previously designed and fabricated in our laboratory has a distinctive feature such that four separation columns of similar weight are mounted symmetrically around the rotary frame to achieve stable balancing of the centrifuge under a high revolution speed. In this column layout, neighboring columns must be rotated in the opposite direction if viewed from the center of the centrifuge to avoid twisting the interconnecting flow tubes. The effect of rotational direction of the columns on the partition efficiency was evaluated with separation of a set of test samples such as cytochrome c, myoglobin, and lysozyme using an aqueous-aqueous polymer phase system composed of 12.5% (w/w) polyethylene glycol (PEG) 1000 and 12.5% (w/w) dibasic potassium phosphate under 1000 rpm of column revolution. A series of experiments was performed using a set of two diagonally located columns (connected in series) each consisting of five coiled layers of 1 mm I.D. with a total capacity of 27.0 mL. Both right- and left-handed coils were tested each under the optimized conditions for choice of mobile phase and direction of the column rotation so that the satisfactory volume of the mobile phase was retained in the column by the aid of Archimedean screw effect. The results of these studies showed that one particular combination of handedness of the coil and direction of the rotation yielded the best peak resolution for each mobile phase. In order to demonstrate the capability of the apparatus, the purification of ribonuclease (RNase) from the extract of bullfrog egg, sialic acid binding lectin (cSBL), was carried out using both organic-aqueous and aqueous-aqueous polymer phase systems. When using the 16.0% (w/w) PEG 1000-6.3% (w/w) dibasic potassium phosphate-6.3% (w/w) monobasic potassium phosphate system, cSBL was successfully separated from other proteins present in the extract while commercial RNase A was eluted at near the solvent front by the lower phase mobile. The cSBL retained its native RNase activity. The overall results demonstrated that the present new small-scale X-axis CPC is useful for the purification of bioactive compounds without loss of their native activities.
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PMID:New small-scale cross-axis coil planet centrifuge. Partition efficiency and application to purification of bullfrog ribonuclease. 1740 Feb 32

Fbs1 is a cytosolic lectin putatively operating as a chaperone as well as a substrate-recognition subunit of the SCF(Fbs1) ubiquitin ligase complex. To provide structural and functional basis of preferential binding of Fbs1 to unfolded glycoproteins, we herein characterize the interaction of Fbs1 with a heptapeptide carrying Man3GlcNAc2 by nuclear magnetic resonance (NMR) spectroscopy and other biochemical methods. Inspection of the NMR data obtained by use of the isotopically labeled glycopeptide indicated that Fbs1 interacts with sugar-peptide junctions, which are shielded in native glycoprotein, in many cases, but become accessible to Fbs1 in unfolded glycoproteins. Furthermore, Fbs1 was shown to inhibit deglycosylation of denatured ribonuclease B by a cytosolic peptide:N-glycanase (PNGase). On the basis of these data, we suggest that Fbs1 captures malfolded glycoproteins, protecting them from the attack of PNGase, during the chaperoning or ubiquitinating operation in the cytosol.
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PMID:Fbs1 protects the malfolded glycoproteins from the attack of peptide:N-glycanase. 1772 Jan 38

Glycopeptides prepared from 1 nmol of a mixture of glycoproteins, transferrin, and ribonuclease B by lysylendopeptidase digestion were isolated by lectin and cellulose column chromatographies, and then they were analyzed by matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry and MALDI-quadrupole ion trap (QIT)-TOF mass spectrometry which enables the performance of MS ( n ) analysis. The lectin affinity preparation of glycopeptides with Sambucus nigra agglutinin and concanavalin A provides the glycan structure outlines for the sialyl linkage and the core structure of N-glycans. Such structural estimation was confirmed by MALDI-TOF MS and MALDI-QIT-TOF MS/MS. Amino acid sequences and location of glycosylation sites were determined by MALDI-QIT-TOF MS/MS/MS. Taken together, the combination of lectin column chromatography, MALDI-TOF MS, and MALDI-QIT-TOF MS ( n ) provides an easy way for the structural estimation of glycans and the rapid analysis of glycoproteomics.
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PMID:Analysis of glycopeptides using lectin affinity chromatography with MALDI-TOF mass spectrometry. 1841 Jan 32

Interleukin-1beta (IL-1beta) has been implicated in various neuropathologies, while IL-1 receptor antagonist (IL-1ra) has been shown to reduce neuronal injury. We investigated the pattern of expression of both cytokines in murine hippocampus after trimethyltin (TMT) intoxication. Using a ribonuclease protection assay, we demonstrated induction of transcription of IL-1beta and IL-1ra 3 days following TMT treatment which correlated with the peak of neuronal apoptosis. At this time, immunocytochemical staining revealed enhanced expression of both cytokines in NG2 proteoglycan expressing ameboid cells located at the site of neurotoxic insult, some of which bound also the microglial marker, lectin. There was some overlap between NG2 and lectin staining. Our results suggest that the two cytokines are involved in apoptotic processes in dentate granule cells and indicate that the pro-apoptotic effect of IL-1beta prevails over the presumed protective action of IL-1ra. The novel finding of expression of both cytokines in NG2(+) cells of ameboid phenotype indicates that these cells, through the regulatory roles of pro- and anti-inflammatory cytokines, may be involved in control of neuronal death or survival after injury.
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PMID:Trimethyltin-evoked apoptosis of murine hippocampal granule neurons is accompanied by the expression of interleukin-1beta and interleukin-1 receptor antagonist in cells of ameboid phenotype, the majority of which are NG2-positive. 1863 41

In order to develop a novel high-throughput tool for monitoring carbohydrate-protein interactions, we prepared carbohydrate or glycoprotein microarrays by immobilizing amino modified carbohydrates on aldehyde-derivatized glass slides or glycoprotein on epoxide-derivatized glass slides and carried out lectin binding experiments by using these microarrays, respectively. The interaction events are marked by attachment of gold nanoparticles followed by silver deposition for signal enhancement. The attachment of the gold nanoparticles is achieved by standard avidin-biotin chemistry. The detection principle is resonance light scattering (RLS). The well-defined recognition systems, namely, three monosaccharides (Man-alpha, Glc-beta and Gal-beta) or three glycoproteins (Asf, RNase A and RNase B) with two lectins (ConA and RCA120), were chosen here to establish the RLS assay, respectively. Highly selective recognition of carbohydrate-protein down to 25.6 pg/mL for RCA120 in solution and 8 microM for Gal-beta and 32 ng/mL for Asf on the microarray spots is demonstrated.
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PMID:Microarray-based study of carbohydrate-protein binding by gold nanoparticle probes. 1885 7

Glycoanalysis is important in the manufacture and quality control of protein therapeutics. An emerging method for glycoanalysis is the use of lectin arrays. Critical to the performance of these arrays is the immobilization of lectin molecules. Polydopamine has recently been shown to adsorb to a wide variety of surfaces. In this study, polydopamine (pDA) was used to modify gold, indium, and iridium surfaces and promote the adhesion of the alpha-mannose-specific lectin concanavalin A (Con A). The activity of the surface-bound lectin was demonstrated with the alpha-mannose-presenting glycoprotein ribonuclease B (RNase B). Surface plasmon resonance spectroscopy (SPRS) was used to demonstrate the selective affinity of RNase B for Con A. Surface-MALDI-TOF MS experiments revealed that the affinity of polydopamine-immobilized Con A for the glycoforms of RNase B is significantly affected by slight variations in oligosaccharide structure and composition. Specifically, surface-bound Con A binds certain Man7, Man8, and Man9 RNase B glycoforms more strongly than Man5 and Man6 glycoforms.
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PMID:Selective binding of RNase B glycoforms by polydopamine-immobilized concanavalin A. 1951 1

Lectins, a class of proteins that reversibly and non-enzymatically bind specific sugars, have been purified from different kinds of legumes. In this study, a 48-kDa lectin (KBL) was purified from Korean large black soybeans using liquid chromatography. The specific hemagglutinating activity of the KBL was 4096 titer/mg. EDTA-induced loss of hemagglutinating activity of KBL could be recovered by addition of Fe(3+) ions and some divalent cations as Ca(2+), Mn(2+), Fe(2+), Cu(2+), Zn(2+), and Pb(2+). Sugars such as D-(+)-galactose, D-(+)-raffinose, L-(+)-arabinose, alpha-D-(+)-melibiose, and alpha-lactose could inhibit the hemagglutinating activity of the lectin. Furthermore, the protein showed high thermal stability as well as stability over a wide range of pH values. KBL inhibited HIV-1 reverse transcriptase activity with an IC(50) of 1.38 microM. However, it was destitute of cytokine releasing, mitogenic, ribonuclease and antifungal activities. In addition, inhibitory activity toward nasopharyngeal cell lines was undetectable in KBL at concentrations up to 20 microM.
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PMID:Biochemical and functional properties of a lectin purified from korean large black soybeans--a cultivar of glycine max. 1971 33

Various lectins have attracted attention as potential microbicides to prevent HIV transmission. Their capacity to bind glycoproteins has been suggested as a means to block HIV binding and entry into susceptible cells. The previously undescribed lectin actinohivin (AH), isolated by us from an actinomycete, exhibits potent in vitro anti-HIV activity by binding to high-mannose (Man) type glycans (HMTGs) of gp120, an envelope glycoprotein of HIV. AH contains 114 aa and consists of three segments, all of which need to show high affinity to gp120 for the anti-HIV characteristic. To generate the needed mechanistic understanding of AH binding to HIV in anticipation of seeking approval for human testing as a microbicide, we have used multiple molecular tools to characterize it. AH showed a weak affinity to Man alpha(1-2)Man, Man alpha(1-2)Man alpha(1-2)Man, of HMTG (Man8 or Man9) or RNase B (which has a single HMTG), but exhibited a strong and highly specific affinity (K(d) = 3.4 x 10(-8) M) to gp120 of HIV, which contains multiple Man8 and/or Man9 units. We have compared AH to an alternative lectin, cyanovirin-N, which did not display similar levels of discrimination between high- and low-density HMTGs. X-ray crystal analysis of AH revealed a 3D structure containing three sugar-binding pockets. Thus, the strong specific affinity of AH to gp120 is considered to be due to multivalent interaction of the three sugar-binding pockets with three HMTGs of gp120 via the "cluster effect" of lectin. Thus, AH is a good candidate for investigation as a safe microbicide to help prevent HIV transmission.
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PMID:Mechanism by which the lectin actinohivin blocks HIV infection of target cells. 1971 26

Phospholipids are used as an additive in capillary electrophoresis to enhance the separation of glycans derived from alpha1-acid glycoprotein, fetuin, and ribonuclease B. The properties of phospholipid preparations are dependent upon composition, hydration, and temperature. Separation performance is evaluated as a function of these variables. A preparation of 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) and 1,2-dihexanoyl-sn-glycero-3-phosphocholine (DHPC), with [DMPC]/[DHPC] = 2.5, in 10% lipid/aqueous buffer at 25 degrees C provides the best separation efficiency at an electric field strength of 400 V/cm. Resolution is enhanced with the additive. Concanavalin A, a lectin selective for high mannose and mannose branching glycans, and alpha1-2,3 mannosidase, an enzyme that cleaves 1-2 and 1-3 mannopyranosyl residues, are incorporated in the separation to provide additional selectivity and to expand the application of phospholipid additives for glycan separation.
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PMID:Transformable capillary electrophoresis for oligosaccharide separations using phospholipid additives. 2007 30

To date only a ribonuclease and a protein with anti-HIV-1 reverse transcriptase activity have been isolated from mushrooms of the genus Russula. In this study a novel lectin, with a molecular weight of 32 kDa, and a unique N-terminal sequence different from other lectins, was isolated from the mushroom Russula lepida. It represents the first lectin isolated from Russula mushrooms. The purification scheme involved (NH4)2SO4 precipitation, ion exchange chromatography on diethylaminoethyl DEAE-cellulose and SP-Sepharose, and fast protein liquid chromatography-gel filtration on Superdex 75. The hemagglutinating activity of the lectin (RLL) was inhibited by inulin and O-nitrophenyl-beta-D-galacto-pyranoside. The lectin was stable at temperatures up to 70 degrees C (half of the activity was preserved at 80 degrees C), and in the presence of NaOH or HCl solutions up to a concentration of 12.5 mM. Its hemagglutinating activity was reduced in the presence of Mn2+, Co2+, and Hg2+ ions, and enhanced by Cu2+ ions. It exhibited antiproliferative activity toward hepatoma Hep G2 cells and human breast cancer MCF-7 cells with an IC(50) of 1.6 microM and 0.9 microM, respectively. Daily intraperitoneal injections of RLL (5.0 mg/kg body weight/day for 20 days) brought about 67.6% reduction in the weight of S-180 tumor. RLL was devoid of antifungal, ribonuclease, and HIV-1 reverse transcriptase inhibitory activities.
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PMID:First isolation and characterization of a novel lectin with potent antitumor activity from a Russula mushroom. 2037 19


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