Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:3.2.1.15 (pectinase)
2,440 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The polygalacturonase (poly(1,4-alpha-D-galacturonide) glycanohydrolase, EC 3.2.1.15) activity of Pectinol is resolved into two fractions (E1 and E2) of about equal total activity on DEAE-cellulose. These fractions are purified from other pectinolytic enzyme activity by Sephadex G-75 chromatography. Both E1 and E2 reduce the viscosity of polygalacturonate by 50% after 7% of the glycosidic bonds are hydrolysed. Their activities are not affected by iodoacetate (1 mM) or EDTA (10 mM). E1 and E2 have different molecular weights (35 000 and 85 000, respectively) and different electrophoretic mobilities on sodium dodecyl sulphate polyacrylamide gels. Their pH (4.1 and 3.8 respectively) and ionic strength optima and specific activities also differ. Both enzymes are inhibited at similar rates by diethyl pyrocarbonate at pH 6 but only E2 is protected from this inhibition by 2% (w/v) polygalacturonate. The rate of change of protein absorbance at 250 nm accompanying this inhibition, and the residues are essential for the activities of both E1 and E2. About 2 molecules of carbethoxyhistidine per subunit of E2 and 0.6 molecules per subunit of E1 are present in the completely inhibited enzymes.20
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PMID:Purification and characterisation of polygalacturonases from a commercial Aspergillus niger preparation. 100 21

Polygalacturonase (EC 3.2.1.15) produced by Fursarium oxysporum f. sp. lycopersici was purified by chromatography on DEAE-cellulose, CM-cellulose, and hydroxyapatite. The purified enzyme consisted of two electrophoretically distinct "isozymes", that behaved as charge isomers during electrophoresis in several different concentrations of polyacrylamide gel. The two isozymes had similar "endo" modes of action on polygalacturonic acid, as determined by comparison of viscosity reduction, reducing group release, and thin-layer chromatography of oligomeric hydrolysis products. Both isozymes hydrolzyed 5% of the substrate bonds in reaching 50% viscosity reduction. The amino acid compositions of the isozymes were similar and their molecular weights were about 37000 as determined by sedimentation equilibrium. Removal of large amounts of carbohydrate during purification did not affect heat stability of the enzymes. A large proportion of the remaining carbohydrate appeared to be covalently linked to the enzyme protein.
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PMID:Characterization of two endopolygalacturonase isozymes produced by Fusarium oxysporum f. sp. lycopersici. 126 32

1. A mild, reproducible extraction procedure, using 0.5% ammonium oxalate, was developed for the isolation of polysaccharides containing d-apiose from the cell wall of Lemna minor. On a dry-weight basis the polysaccharide fractions extracted with ammonium oxalate made up 14% of the material designated cell walls and contained 20% of the d-apiose originally present in the cell walls. The cell walls, as isolated, contained 83% of the d-apiose present in L. minor. 2. After extraction with ammonium oxalate, purified polysaccharides were obtained by DEAE-Sephadex column chromatography and by fractional precipitation with sodium chloride. With these procedures the material extracted at 22 degrees C could be separated into at least five polysaccharides. On a dry-weight basis two of these polysaccharides made up more than 50% of the material extracted at 22 degrees C. There was a direct relationship between the d-apiose content of the polysaccharides and their solubility in sodium chloride solutions; those of highest d-apiose content were most soluble. 3. All the polysaccharides isolated appeared to be of one general type, namely galacturonans to which were attached side chains containing d-apiose. The d-apiose content of the apiogalacturonans varied from 7.9 to 38.1%. The content of esterified d-galacturonic acid residues in all apiogalacturonans was low, being in the range 1.0-3.5%. Hydrolysis of a representative apiogalacturonan with dilute acid resulted in the complete removal of the d-apiose with little or no degradation of the galacturonan portion. 4. Treatment of polysaccharide fractions with pectinase established that those of high d-apiose content and soluble in m-sodium chloride were not degraded, whereas those of low d-apiose content and insoluble in m-sodium chloride were extensively degraded. When the d-apiose was removed from a typical pectinase-resistant polysaccharide, the remainder of the polysaccharide was readily degraded by this enzyme. 5. Periodate oxidation of representative polysaccharide fractions and apiogalacturonans and determination of the formaldehyde released showed that about 50% of the d-apiose molecules were substituted at either the 3- or the 3'-position.
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PMID:Isolation and partial characterization of apiogalacturonans from the cell wall of Lemna minor. 431 31

The amount of polygalacturonase-inhibiting protein (PGIP) was 14 times higher in bean pods than in etiolated hypocotyls. The PGIP was extracted from bean pods and partially purified by chromatography on columns of S-Sepharose. DEAE-Sephadex A-50, and Sephadex G-75. Further purification by ion-exchange chromatography on a Mono Q column separated two isoforms of the inhibitor. The two PGIPs were similar in most properties but differed slightly in pI values. They also differed in one residue of the N-terminal amino acid sequences. Both bean pod PGIPs differed in two and possibly three residues of the deduced N-terminal amino acid sequence for hypocotyl PGIP. Small alterations in the structure of PGIP may represent a strategy in bean plants for resistance to a variety of pathogens.
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PMID:Polygalacturonase inhibitors in bean pods. 939 4

Three multiple forms of polygalacturonase (PG) in ripe and two in unripe banana (Musa acuminata) fruits were separated by DEAE-cellulose and further purified using Sephadex G-150 chromatography. The multiple forms can be differentiated from each other on the basis of their properties. PG1 and PG3 were identified as endo-PG and PG2 as exo-PG on the basis of decrease in viscosity, increase in reducing sugar and the reaction product. PG2 and PG3 increased with the ripening of fruits. PG1, PG2 and PG3 exhibited optimum activity at pH 3.3, 3.7 and 4.3, respectively. Complete loss of PG2 and PG1 activities occurred at 60 and 70 degrees, but PG3 retained 60 and 50% activity respectively. The three forms showed a different response towards divalent metal ions. Ca2+ activated PG1 activity only. Teepol 0.1%, inhibited PG1 activity by 25%, but PG2 and PG3 activities were completely inhibited. CTAB, 0.1%, had no effect on PG1 and PG2 activities, but inhibited PG3 activity by 40%. 2-ME stimulated PG2 and PG3 activities but had no effect on PG1 activity. Gel filtration through Sephacryl indicated M(r) of 23,200, 58,000 and 130,000, respectively, for PG1, PG2 and PG3. The substrate saturation curve for PG1 and PG2 were Michaelian, while PG3 showed biphasic curve. The Km values of PG1 and PG2 were 0.22% and 0.14%, respectively.
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PMID:Multiple forms of polygalacturonase from banana fruits. 963 63

Water-soluble polysaccharide fractions VO1-VO4 were isolated from the squeezed berries of snowball tree (Viburnum opulus) by successive extraction with water at various temperatures and pH and with aqueous solutions of ammonium oxalate. These fractions were purified by ion-exchange chromatography on DEAE cellulose, and the homogeneity of the purified polysaccharides was determined by gel filtration on Sephacryl S-500. Acidic polysaccharides close to pectins in their sugar composition were found in all the extracts (fractions VO1-1, VO2-1, VO3-2, and VO4-2). Residues of galacturonic acid, galactose, arabinose, and (to a lesser extent) rhamnose are their main constituents. Neutral polysaccharides composed mainly of galactose and mannose residues were additionally found in fractions extracted with acidified water (pH 4.0) and with aqueous ammonium oxalate solutions. Partial acidic hydrolysis and digestion with pectinase of acidic polysaccharides indicated that their carbohydrate backbone consists of alpha-1,4-linked residues of D-galacturonic acid. NMR spectra of acidic polysaccharides (fractions VO3-2 and VO3-3) confirmed this and demonstrated that their side oligosaccharide chains are composed of beta-1,4-linked galactopyranose residues and of terminal and 2,5- and 3,5-substituted residues of alpha-arabinofuranose at a Gal: Ara ratio of 3:1. Some polysaccharides from V. opulus were found to possess an immunostimulating activity: they enhance phagocytosis, in particular, the phagocytic index and the secretion of lysosomal enzymes with peritoneal macrophages. Calcium ions were found to be necessary for the appearance of the stimulating effect of acidic polysaccharides from V. opulus.
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PMID:[The isolation, preliminary study of structure and physiological activity of water-soluble polysaccharides from squeezed berries of Snowball tree Viburnum opulus]. 1080 53

Polysaccharides from the roots of Panax ginseng were extracted by hot water and fractionated by using ethanol precipitation and ion exchange chromatography. Fractions FC (crude extract), F1 (fraction precipitated by ethanol), F1N (fraction unbound to DEAE-Sepharose CL-6B), and F1A (bound fraction) were obtained. Their carbohydrate analyses showed that acidic fraction F1A contains higher amounts of galactose, arabinose and uronic acids, in comparison to FC and F1. Fraction F1N mainly consists of glucose. The inhibition of Helicobacter pylori-induced hemagglutination revealed different inhibitory activities of these fractions. In particular, acidic fraction F1A showed a remarkable inhibitory activity (minimum inhibition concentration was 0.25 mg/ml) among the polysacharide fractions. However, digestion of the fraction F1A with pectinase resulted in a lower molecular weight oligosaccharide fraction F1AP which was non-inhibitory at the concentration of 4 mg/ml. Comparison of inhibitory activities and carbohydrate compositions of isolated fractions indicates that the activity correlated with the contents of galactose, arabinose, and uronic acids. These data suggest that acidic polysaccharides may be responsible for the inhibitory activity.
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PMID:Inhibition of Helicobacter pylori hemagglutination by polysaccharide fractions from roots of Panax ginseng. 1082 Oct 45

Extracts from apple fruit (cultivar "Granny Smith") inhibited the cell-wall degrading polygalacturonase (PG) activity of Colletotrichum lupini, the causal agent of anthracnose on lupins, as well as Aspergillus niger PG. Southern blot analysis indicated that this cultivar of apple has a small gene family of polygalacturonase inhibiting proteins (pgips), and therefore heterologous expression in transgenic tobacco was used to identify the specific gene product responsible for the inhibitory activity. A previously isolated pgip gene, termed Mdpgip1, was introduced into tobacco (Nicotiana tabacum) by Agrobacterium-mediated transformation. The mature MdPGIP1 protein was purified to apparent homogeneity from tobacco leaves by high salt extraction, clarification by DEAE-Sepharose and cation exchange HPLC. Purified MdPGIP1 inhibited PGs from C. lupini and PGs from two economically important pathogens of apple trees, Botryosphaeria obtusa and Diaporthe ambigua. It did not inhibit the A. niger PG, which was in contrast to the apple fruit extract used in this study. We conclude that there are at least two active PGIPs expressed in apple, which differ in their charge properties and ability to inhibit A. niger PG.
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PMID:Apple polygalacturonase inhibiting protein1 expressed in transgenic tobacco inhibits polygalacturonases from fungal pathogens of apple and the anthracnose pathogen of lupins. 1636 81

Single plant cells have been obtained without the preparation of protoplasts by culturing pieces of soybean callus tissue with colchicine. Cell expansion and separation were evoked by colchicine (1 mM) within a week of culture. Microscopic observation showed that cells took on a spherical shape in the presence of colchicine and then separated into single cells. Addition of colchicine to the culture medium did not affect the composition of cell wall polysaccharides, but a uronic acid-rich extracellular polysaccharide appeared during cell expansion and separation. Addition of microtubule stabilizers, glycerol (300 mM) or dimethyl sulfoxide [3% (vol/vol)], inhibited the secretion of the polysaccharide as well as cell expansion and separation. The extracellular polysaccharide elicited by colchicine was isolated by ion-exchange chromatography on DEAE-Sepharose and gel filtration on Sepharose CL-6B from the conditioned medium of colchicine-treated soybean cells. The purified 18-kDa polysaccharide immediately enhanced cell expansion and separation when added to soybean callus tissue cultured in medium containing colchicine, even at low concentrations (0.1 mM). The polysaccharide was composed of galacturonic acid and, after digestion with a pectinase preparation, had no effect on the cells. Methylation analysis suggests that the polysaccharide consists of approximately 100 sequential alpha-1,4-galacturonic acids. The galacturonan increased the viability of separated cells cultured in medium containing colchicine, and the single cells obtained did not produce a wound-response callose. (Aminoethoxyvinyl)glycine, a specific inhibitor of ethylene production, extensively decreased the cell expansion and separation but did not inhibit the formation of the extracellular polysaccharide, suggesting that the polysaccharide may exert its effect by stimulating ethylene production.
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PMID:Cell expansion and single-cell separation induced by colchicine in suspension-cultured soybean cells. 1659 25

Purification of pea (Pisum sativum) seedling NAD kinase by DEAE-cellulose column chromatography resulted in loss of activity, due to dissociation of an activator from the enzyme. The purified enzyme preparation, which was almost completely inactive, regained the activity when the activator was added back.The activator was purified 320-fold by ion exchange chromatographies. The activator was susceptible to proteolytic enzymes, but not to ribonuclease, glucoamylase or pectinase, indicating that it is of a protein nature. This protein was relatively stable in boiling water, but susceptible to acid or alkali, especially under high temperatures. Restoration of catalytic activity of inactive enzyme was proportional to amounts of the activator added. Gel filtration indicated that molecular weight of the activator was 28,000.The activator was found in extracts from various plants.
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PMID:Properties of a Protein Activator of NAD Kinase from Plants. 1665 89


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