Purification and Characterization of a Novel β-<Emphasis Type="SmallCaps">d</Emphasis>-Galactosides-Specific Lectin from <Emphasis Type="Italic">Clitoria ternatea</Emphasis>

A lectin present in seeds of Clitoria ternatea agglutinated trypsin-treated human B erythrocytes. The sugar specificity assay indicated that lectin belongs to Gal/Gal NAc-specific group. Hence the lectin, designated C. ternatea agglutinin (CTA), was purified by the combination of acetic acid precipitation, salt fractionation and affinity chromatography. HPLC gel filtration, SDS-polyacrylamide gel electrophoresis and mass spectrometry indicated that the native lectin is composed of two identical subunits of molecular weight 34.7 kDa associated by non covalent bonds. The N-terminal sequence of CTA shared homology with Glycine max and Pisum sativum. Complete sequence was also found to be homologous to S-64 protein of Glycine max, suggesting that CTA probably exhibits both hemagglutination and probably sugar uptake activity. The carbohydrate binding specificity of the lectin was investigated by quantitative turbidity measurements, and percent inhibition assays. Based on these assays, we conclude that CTA binds β-d-galactosides, and also may has an extended specificity towards non-reducing terminal Neu5Acα2,6Gal.     

Purification and partial characterization of cell surface glycoprotein from extremely halophilic archaeon Haloarcula japonica strain TR-1

Summary Haloarculajaponica has a glycoprotein on its cell surface. The cell surface glycoprotein of H. japonica was purified and characterized. It had an apparent molecular mass of 180 kDa in sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The carbohydrate content was about 12% (wt/wt). The polypeptide portion contained a large proportion of acidic amino acids, and the sequence of 18 N-terminal amino acids was determined.     

Purification and biochemical characterization of glucose 6-phosphate dehydrogenase, 6-phosphogluconate dehydrogenase and glutathione reductase from rat lung and inhibition effects of some antibiotics

G6PD, 6PGD and GR have been purified separately in the single step from rat lung using 2′, 5′-ADP Sepharose 4B affinity chromatography. The purified enzymes showed a single band on sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The molecular weights of the enzymes were estimated to be 134?kDa for G6PD, 107?kDa for 6PGD and 121?kDa for GR by Sephadex G-150 gel filtration chromatography, and the subunit molecular weights was respectively found to be 66, 52 and 63?kDa by SDS-PAGE. Optimum pH, stable pH, optimum ionic strength, optimum temperature, K_M and V_max values for substrates were determined. Product inhibition studies were also performed. The enzymes were inhibited by levofloxacin, furosemide, ceftazidime, cefuroxime and gentamicin as in vitro with IC₅₀ values in the range of 0.07–30.13?mM. In vivo studies demonstrated that lung GR was inhibited by furosemide and lung 6PGD was inhibited by levofloxacin.     

Purification and characterization of a unique osteoinductive factor from bovine bone

A unique protein that promotes ectopic osteoinduction in the rat has been isolated and characterized. Osteoinductive factor (OIF) was extracted from the organic matrix of bovine bone with 4 M guanidine HCl and purified by gel filtration, ion-exchange chromatography, affinity chromatography, and reversed phase high performance liquid chromatography. OIF is a glycoprotein with an apparent molecular mass of 22-28 kDa based on sodium dodecyl sulfate gel electrophoresis. Enzymatic or chemical deglycosylation of OIF reduces its mass to about 12 kDa with apparent loss of activity. OIF activity in the model used is substantially increased by addition of transforming growth factor (TGF)-beta 1 or TGF-beta 2, suggesting an important role for TGF-beta 1 and -2 in bone regeneration and repair. The N-terminal sequence of OIF has no homology to other reported proteins.     

Carbohydrate-binding profile of a pregnancy-associated rat uterine glycoprotein

Sugar-binding proteins obtained from the peri-implantation uterine tissue have been thought in recent years to have significant roles in embryo implantation, where carbohydrate moieties of the protein are actively involved. Based on this rationale a mannose-containing glycoprotein/lectin (named uterine agglutinin or UA) was purified by Concanavalin A (Con A) affinity chromatography in a previous study. A modification of the original purification procedure to include a 33% ammonium sulfate fractionation improves the yield of the protein significantly. An alternative purification procedure by Mannan affinity matrix, indicates that apart from containing mannose, UA possesses mannose-binding properties as well.In this paper, we report some of the biochemical and more specifically, the carbohydrate-binding characteristics of UA. The protein is seen to contain mannose-6-phosphate (M-6-P)-binding sites, which is of importance since M-6-P receptors have a large number of biologically significant roles, including that of binding to growth factors.SDS-PAGE, gel filtration chromatography and alkaline PAGE indicate the homogenous nature of the protein with subunit molecular weights of 36 kDa and 19 kDa, and a native size of 64kDa. Amino acid analysis shows glycine, glutamic acid and aspartic acid to be the major constituents.UA is a glycoprotein and shows presence of N-acetyl glucosamine and galactose, apart from mannose.De nove synthesis studies in the presence of tunicamycin show that the carbohydrate moiety of the glycoprotein is attached by N-linkage to the protein. Binding characteristics of the protein is studied quantitatively in which (¹²⁵I)-labelled lectin is bound to Mannan-Sepharose affinity matrix. The sugar inhibition pattern of this binding shows -methyl mannopyranoside and M-6-P to be equally effective as inhibitors. Scatchard analysis of the binding of UA to (¹⁴C)-mannose shows a Ka of 6.43×10⁵ (M^–1) and that 1 mole of UA can bind to 8 moles of mannose. The possible role of the protein in implantation has also been discussed.Abbreviations b.w. body weight - BSA Bovine Serum Albumin - Con A Concanavalin A - cpm counts per minute - Endo H endoglycosidase H - GlcNAc N-acetyl glucosamine - Man mannose - M-6-P mannose-6-phosphate - MEM-deficient Minimum Essential Medium Eagle-deficient modification - NaBH₄ sodium borohydride - NaN₃ sodium azide - (NH₄)₂SO₄ ammonium sulphate - p.c. post coitum - PMSF phenyl methyl sulphonyl fluoride - PTA phosphotungstic acid - RCA Ricinus communis Agglutinin - SDS-PAGE sodium dodecyl sulphate-polyacrylamide gel electrophoresis - TCA trichloroacetic acid - UA Uterine Agglutinin - WGA Wheat-germ Agglutinin     

Overexpression and Purification of Rhizobium etli Glutaminase A by Recombinant and Conventional Procedures: A Comparative Study of Enzymatic Properties

Rhizobium etli glutaminase A was purified to homogeneity by conventional procedures that included ammonium sulfate differential precipitation, ion-exchange chromatography, hydrophobic interaction chromatography, gel filtration, and dye-ligand chromatography. Alternatively, the structural glsA gene that codifies for glutaminase A was amplified by PCR and cloned in the expression vector pTrcHis. The recombinant protein was purified to homogeneity by affinity chromatography. This protein showed the same kinetic properties as native glutaminase A (K_m for glutamine of 1.5 mM and V_max of 80 μmol ammonium min⁻¹ mg protein⁻¹). Physicochemical and biochemical properties of native and recombinant glutaminase were identical. The molecular mass of recombinant glutaminase A (M_r 106.8 kDa) and the molecular mass of the subunits (M_r 26.9 kDa) were estimated by mass spectrometry. These results suggest that R. etli glutaminase A is composed of four identical subunits. The high-level production of recombinant glutaminase A elevates the possibilities for determination of its three-dimensional structure through X-ray crystallography.     

Purification and characterization of a XIP-type endoxylanase inhibitor from Rice (Oryza sativa)

A rice XIP-type inhibitor was purified by affinity chromatography with an immobilized Aspergillus aculeatus family 10 endoxylanase. Rice XIP is a monomeric protein, with a molecular mass of ca. 32?kDa and a pI of ca. 5.6. Its N-terminal amino acid sequence was identical to that of a rice chitinase homologue, demonstrating the difficulty when using sequence information to differentiate between endoxylanase inhibitors and (putative) chitinases in rice. Rice XIP inhibited different endoxylanases to a varying degree. In particular, it most strongly inhibited family 10 endoxylanases from A. niger and A. oryzae, while several family 11 enzymes from Bacillus subtilis, A. niger and Trichoderma sp. were not sensitive to inhibition. The above mentioned A. aculeatus endoxylanase was not inhibited either, although gel permeation chromatography revealed that it complexed rice XIP in a 1:1 molar stoichiometric ratio.     

Purification and partial characterization of a new mannose/glucose‐specific lectin from Dialium guineense Willd seeds that exhibits toxic effect

A new mannose/glucose‐specific lectin, named DigL, was purified from seeds of Dialium guineense by a single step using a Sepharose 4b‐Mannose affinity chromatography column. DigL strongly agglutinated rabbit erythrocytes and was inhibited by d ‐mannose, d ‐glucose, and derived sugars, especially α‐methyl‐d ‐mannopyranoside and N‐acetyl‐d ‐glucosamine. DigL has been shown to be a stable protein, maintaining its hemagglutinating activity after incubation at a wide range of temperature and pH values and after incubation with EDTA. DigL is a glycoprotein composite by approximately 2.9% of carbohydrates by weight. By sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis, the purified DigL exhibited an electrophoretic profile consisting of a broad band of 28–30 kDa. Analysis using electrospray ionization mass spectrometry indicated that purified DigL possesses a molecular average mass of 28 452 ± 2 Da and shows the presence of possible glycoforms. In addition, DigL exhibited an intermediary toxic effect on Artemia sp. nauplii, and this effect was both dependent on native structure and mediated by a carbohydrate‐binding site. Copyright © 2013 John Wiley & Sons, Ltd.     

A thermostable manganese-containing superoxide dismutase from the thermophilic fungus Thermomyces lanuginosus

A thermostable superoxide dismutase (SOD) from a Thermomyces lanuginosus strain (P134) was purified to homogeneity by fractional ammonium sulfate precipitation, ion-exchange chromatography on DEAE-Sepharose, Phenyl-Sepharose hydrophobic interaction chromatography, and gel filtration on Sephacryl S-100. The molecular mass of a single band of the enzyme was estimated to be 22.4 kDa, using sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Using gel filtration on Sephacryl S-100, the molecular mass was estimated to be 89.1 kDa, indicating that this enzyme was composed of four identical subunits of 22.4 kDa each. The SOD was found to be inhibited by NaN₃, but not by KCN or H₂O₂, suggesting that the SOD in T. lanuginosus was of the manganese superoxide dismutase type. The SOD exhibited maximal activity at pH 7.5. The optimum temperature for the activity was 55°C. It was thermostable at 50 and 60°C and retained 55% activity after 60 min at 70°C. The half-life of the SOD at 80°C was approximately 28 min and even retained 20% activity after 20 min at 90°C.     

Purification and characterization of oxalate oxidase from wheat seedlings

Oxalate oxidase (OxO, EC 1.2.3.4.) was purified to homogeneity from wheat (Triticum aestivum) seedlings by sequential thermal treatment, ultrafiltration, Sephadex G-100 gel filtration and affinity chromatography with concanavalin A. The enzyme was purified 66.11-fold with a recovery of 21.97%. It showed a subunit molecular mass of 32.6 kDa on SDS-PAGE and a native molecular mass of 170 kDa on Sephadex G-150 filtration, suggesting that it is a pentamer. The wheat OxO had a maximum activity at pH 3.5. Its K _m for oxalate was 0.21 mM. Chemical modification revealed that cysteine, lysine and carboxylate residues were essential for OxO activity, whereas arginine, serine, threonine and tryptophane residues were not essential.     

Macluralisin — a serine proteinase from fruits of Maclura pomifera (Raf.) Schneid.

A serine proteinase was isolated from fruits of Maclura pomifera (Raf.) Schneid. by affinity chromatography on bacitracin-containing sorbents and gel-filtration. The enzyme, named macluralisin, is a glycoprotein with a molecular mass of 65 kDa; its protein moiety corresponds to a molecular mass of 50 kDa. The substrate specificity of macluralisin towards synthetic peptides and insulin B-chain is similar to that of cucumisin, a subtilisin-like proteinase from melon fruit. The enzyme is completely inhibited by diisopropylfluorophosphate. Its amino-acid composition resembles that of a serine proteinase isolated from the Cucurbitaceae. The N-terminal sequence has 33% of its residues identical to those of the sequence of fungal subtilisin-like proteinase K. Hence, Maclura pomifera serine proteinase belongs to the subtilisin family, which seems to be broadly distributed in the plant kingdom.Abbreviations DFP diisopropylfluorophosphate - PMSF phenylmethylsulfonylfluoride - Glp pyroglutamyl - NHC₆H₄NO₂ p-nitroanilide This work was supported in part by a grant from the Russian Foundation for Basic Research.     

Purification and characterization of tannase from Paecilomyces variotii: hydrolysis of tannic acid using immobilized tannase

An extracellular tannase (tannin acyl hydrolase) was isolated from Paecilomyces variotii and purified from cell-free culture filtrate using ammonium sulfate precipitation followed by ion exchange and gel filtration chromatography. Fractional precipitation of the culture filtrate with ammonium sulfate yielded 78.7% with 13.6-folds purification, and diethylaminoethyl–cellulose column chromatography and gel filtration showed 19.4-folds and 30.5-folds purifications, respectively. Molecular mass of tannase was found 149.8 kDa through native polyacrylamide gel electrophoresis (PAGE) analysis. Sodium dodecyl sulphate–PAGE revealed that the purified tannase was a monomeric enzyme with a molecular mass of 45 kDa. Temperature of 30 to 50°C and pH of 5.0 to 7.0 were optimum for tannase activity and stability. Tannase immobilized on alginate beads could hydrolyze tannic acid even after extensive reuse and retained about 85% of the initial activity. Thin layer chromatography, high performance liquid chromatography, and ¹H-nuclear magnetic resonance spectral analysis confirmed that gallic acid was formed as a byproduct during hydrolysis of tannic acid.     

Purification, Biological Activities, and Molecular Cloning of a Novel Mannose-Binding Lectin from Bulbs of Zephyranthes candida Herb （Amaryllidaceae）

A novel mannose-bindlng aggiutinln was purified from bulbs of Zephyranthes candida Herb by extraction, precipitation with 80% （NH4）2SO4, and ion-exchange chromatography on DEAE-Sepharose followed by gel flitration on Sephscryl S-100. The purified Z. candida agglutlnln （ZCA） migrated as a single band of 12 kDa on sodium dodecyi suifate-poiyecryiamide gel electrophoresis under reducing and non-reducing conditions. The apparent molecular mass of the iectln, as datermlned by gel filtration chromatography, was 48 kDa. The results Indicated that ZCA was composed of four Identical subunlts of 12 kDa each （homotetramerlc nature）. The ZCA agglutlhated rabbit erythrocytes, Escherichla coil and Saccharomyces cerevislae ceils at concentrations of 0.95, 1.90, and 31.30 μg/mL, respectively. Bloassays Indicated that ZCA has a significant effect on wheat aphid survival. Mortality after 7 d was 〉 90% at 0.26%. A degenerate primer was designed In accordance with the N-terminal partial sequence of purified ZCA. The full-length cDNA was cloned by 3＇- and 5＇-rapid amplification of cDNA ends. The full-length cDNA had 661 bp and the sequence encoded an open reading frame of 168 amino acids. The mature protein of ZCA Includes 109 amino acid residues and the molecular weight of the protein was 12.1 kDa. The result show that the zca gene encodes a protein precursor with a signal peptlde, a mature protein, and a C-terminal cleavage amino acids sequence. Molecular modeling of ZCA Indicated that Its three-dimensional atructure strongly resembies that of the snowdrop aggiutinin. Blocks＇ analysis revealed that the deduced amino acid sequence of ZCA has three functional domains specific for agglutination and three carbohydrate binding boxes （QDNY）.     

Isolation and Some Properties of Acid Phosphatase-11 from Tomato Leaves

An isozyme of acid phosphatase-1, acid phosphatase-1¹, was purified from the leaves of tomato (Lycopersicon esculentum) to homogeneity and characterized. The purified enzyme was homogeneous on polyacrylamide gel electrophoresis with or without sodium dodecyl sulfate. The gel filtration analysis showed that the native molecule had a relative molecular mass of about 61 kilodaltons (kDa). The relative molecular mass of the subunit on gel electrophoresis with sodium dodecyl sulfate was about 32 kDa, indicating that the native form of the enzyme was a homodimer. It was suggested by periodic acid-Schiff staining on the gel that the enzyme was a glycoprotein. The Km for p-nitrophenylphosphate was 2.9 × 10^?3 m. The enzyme had a pH optimum of 4.5 in 0.15 m potassium acetate buffer with p-nitrophenylphosphate as a substrate. This enzyme was activated by divalent metal ions, such as Zn²⁺, Mg²⁺, and Mn²⁺. The N-terminal amino acids were sequenced after the purified enzyme was treated with pyroglutamylpeptidase. It was suggested that the N-terminal amino acid was pyroglutamate.     

Thermostable d-hydantoinase from thermophilic Bacillus stearothermophilus SD-1: characteristics of purified enzyme

One thousand thermophiles isolated from soils were screened for hydantoinase and its thermostability. One thermophilic bacterium that showed the highest thermostability and activity of hydantoinase was identified to be Bacillus stearothermophilus SD-1 according to morphological and physiological characteristics. The hydantoinase of B. stearothermophilus SD-1 was purified to homogeneity via ammonium sulfate fractionation, anion-exchange chromatography, heat treatment, hydrophobic-interaction chromatography, and preparative gel electrophoresis. The relative molecular mass of the hydantoinase was determined to be 126 kDa by gel-filtration chromatography, and a value of 54 kDa was obtained as a molecular mass of the subunit on analytical sodiumdodecylsulfate/polyacrylamide gel electrophoresis. The hydantoinase was strictly d-specific and metal-dependent. The optimal pH and temperature were about 8.0 and 65°C respectively, and the half-life of the d-hydantoinase was estimated to be 30 min at 80°C, indicating the most thermostable enzyme so far.     

Studies on (K + H)-ATPase. V. Chemical composition and molecular weight of the catalytic subunit

(1) A (K⁺ + H⁺)-ATPase preparation from porcine gastric mucosa is solubilized in sodium dodecyl sulfate, and is subjected to gel filtration. (2) A main subunit fraction is obtained, which is a protein carbohydrate lipid complex, containing 88% protein, 7% carbohydrate and 5% phospholipid. The detailed composition of the protein and carbohydrate moieties are reported. (3) Sedimentation analysis of the subunit preparation, after detergent removal, reveals no heterogeneity, but the subunits readily undergo aggregation. (4) Acylation of the subunit preparation with citraconic anhydride causes a clear shift of the band obtained after SDS gel electrophoresis, but the absence of broadening and splitting of the band pleads against subunit heterogeneity. (5) Treatment of the subunit preparation with dansyl chloride indicates that the NH₂ terminus is blocked, which favors the assumption of homogeneity of the protein. (6) Binding studies with concanavalin A indicate that at least 86% of the subunit preparation is composed of glycoprotein. (7) These findings, taken together, strongly suggest that there is a single subunit which is a glycoprotein and which represents the catalytic subunit of the enzyme. From sedimentation equilibrium analysis a molecular mass value of 119 kDa (S.E. 3, n = 6) is calculated for protein + carbohydrate and of 110 kDa (S.E. 3, n = 6) for protein only. (8) In combination with the molecular mass of 444 kDa (S.E. 10, n = 4) obtained for the intact enzyme by radiation inactivation we conclude that the enzyme appears to be composed of a homo-tetramer of catalytic subunits.     

Purification and properties of a thermostable extracellular β-D-xylosidase produced by a thermotolerant Aspergillus phoenicis

A β-D-xylosidase was purified from cultures of a thermotolerant strain of Aspergillus phoenicis grown on xylan at 45°C. The enzyme was purified to homogeneity by chromatography on DEAE-cellulose and Sephadex G-100. The purified enzyme was a monomer of molecular mass 132 kDa by gel filtration and SDS-PAGE. Treatment with endoglycosidase H resulted in a protein with a molecular mass of 104 kDa. The enzyme was a glycoprotein with 43.5% carbohydrate content and exhibited a pI of 3.7. Optima of temperature and pH were 75°C and 4.0–4.5, respectively. The activity was stable at 60°C and had a K _m of 2.36 mM for p-nitrophenyl-β-D-xylopiranoside. The enzyme did not exhibit xylanase, cellulase, galactosidase or arabinosidase activities. The purified enzyme was active against natural substrates, such as xylobiose and xylotriose. Journal of Industrial Microbiology & Biotechnology (2001) 26, 156–160. Received 23 June 2000/ Accepted in revised form 29 September 2000     

Purification and partial characterization of a fibrinolytic enzyme from the fruiting body of the medicinal and edible mushroom Pleurotus ferulae

A fibrinolytic metalloprotease with in vitro fibrinolytic effects was purified from the edible mushroom Pleurotus ferulae using several chromatography steps including anion and ion exchange, gel filtration, and fast protein liquid chromatography columns. The molecular mass of the enzyme was estimated to be 20.0?kDa, as determined using sodium dodecyl sulfate-polyacrylamide gel electrophoresis and fibrin zymography. The protease was active at 50°C, and pH 4.0, 5.0, and 8.0. The fibrinolytic activity of the enzyme was inhibited by ethyleneglycol-bis-(2-aminoethyl)-N,N,N′,N′ tetraacetic acid and strongly inhibited by two metal ions, Cu and Mg. In vitro assays evaluating fibrinolytic activity on a fibrin plate, fibrin turbidity, and thrombolytic activity on fibrin clots using human fibrinogen and human thrombin revealed that the enzyme could hydrolyze fibrin polymers directly and inhibit the formation of fibrin clots. In activated partial thromboplastin time (APTT) and prothrombin time assays, the enzyme strongly prolonged the APTT, which detects an activity of intrinsic and common pathways. The enzyme showed strong in vivo protective effect against mortality/paralysis from epinephrine plus collagen-induced acute thromboembolism in in vivo model. Our findings suggest that the enzyme may have a potential for treatment and prevention of thrombosis-relative diseases.     

Direct demonstration of heterogeneous,sulfatedO-linked carbohydrate chains on an endothelial ligand for L-selectin

We have previously identified endothelial ligands for L-selectin as sialylated, fucosylated and sulfated glycoproteins of approximately 50 kDa and 90 kDa (Sgp50 and Sgp90). In this report, we use the beta elimination reaction to demonstrate directly the presence of sulfatedO-linked sugar chains on one of these ligands, after metabolic labeling with radiolabeled sulfate or fucose. All of the sulfated and the majority of the fucosylatedO-linked sugar chains were shown to be sialylated by affinity chromatography on a Limax agglutinin column. Analyses by anion exchange and gel permeation chromatography revealed a complexity of sugar chains, which were heterogeneous both in charge and size. Charged groups other than sialic acid appeared to exert a predominant influence on the total charge of the sugar chains. The probable existence of a varying number of sulfate modifications per sugar chain is discussed.     

Surface glycoprotein of human natural killer cells recognized by wheat germ agglutinin

We analyzed surface glycoproteins of human natural killer (NK) cells by utilizing lectins. Among the lectins tested, wheat germ agglutinin (WGA) was found to bind preferentially to CD16(Leu11)-positive lymphocytes as determined by two-colour flow cytometry. Analysis of glycoproteins in the lysate prepared from NK cells with sodium dodecyl sulfate (SDS) gel electrophoresis followed by Western blotting and¹²⁵I labeled WGA staining revealed that a glycoprotein with anM _r of 65 kDa was strongly bound to the lectin, but no corresponding glycoprotein was detected in the lysate of T lymphocytes. This glycoprotein (GP65) gave several spots in the pI range 4.1–4.6 on 2-dimensional gel electrophoresis. Sialidase treatment of GP65 resulted in a single spot on the 2-dimensional gel, suggesting that GP65 is heterogeneous in the degree of sialylation. GP65 was shown to be exposed on the cell surface, since it was radiolabeled with¹²⁵I by the lactoperoxidase-catalyzed method. We next isolated GP65 from human peripheral blood lymphocytes by a combination of chromatography on a cation-exchange column and a WGA-agarose column and preparative SDS gel electrophoresis. It is suggested that GP65 is a novel surface glycoprotein on human NK cells.