logging in or signing up Cell wall degrading enzymes chilesatish Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINT lite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: (To copy code, click on the text box) Embed: URL: Thumbnail: WordPress Embed Customize Embed The presentation is successfully added In Your Favorites. Views: 1832 Category: Science & Tech.. License: All Rights Reserved Like it (1) Dislike it (0) Added: April 21, 2009 This Presentation is Public Favorites: 0 Presentation Description Cell wall degrading enzymes play a key role in the development on plant diseases caused by plant pathogens. Comments Posting comment... By: framsis2nd (32 month(s) ago) Nice Saving..... Post Reply Close Saving..... Edit Comment Close Premium member Presentation Transcript Cell wall degrading enzymes : Cell wall degrading enzymes These are macerating factors. These includes; 1. Cellulases 2. Pectinases 3. Hemicelluloses 4. Proteases 5. Cutinases 6. Lignases Chile Slide 2: Chile Cuticular enzymes : Cuticular enzymes The major chemical substances in cuticle is a cutin framework with waxes embedded in it and extruded from its surface to give a water proof surface (the Cuticular wax). Cutin is a polyester of hydroxylated monocarboxylic acids ( with 16 to 18 carbons and 2 to 3 hydroxyl groups.) Wax contains complex mixture of long chains paraffin, alcohols, ketones, esters and acids. Chile Slide 4: Role of enzymes in the dissolution of cuticle is not very well understood. Various enzymes have been suggested in dissolution of cuticle; Cutinesterases Cutinases Lipases A mixture of enzymes includes protease. Cellulases and Pectinases etc.( Germinating spores of Colletotrichum gloeosprioides on orange leaves, Spaerothece pannosa on Rose leaves, Venturia inaequalis on Apple, and Helminthosporium victoriae. Chile Cellulose : Cellulose Cellulose is probably the single most abundant organic molecule in the biosphere. It is the major structural material of which plants are made. Wood is largely cellulose while cotton and paper are almost pure cellulose. Chile Slide 6: Because of the orientation of the glycosidic bonds linking the glucose residues, the rings of glucose are arranged in a flip-flop manner. This produces a long, straight, rigid molecule. There are no side chains in cellulose as there are in starch. The absence of side chains allows these linear molecules to lie close together. Chile Slide 7: Because of the many -OH groups, as well as the oxygen atom in the ring, there are many opportunities for hydrogen bonds to form between adjacent chains. The result is a series of stiff, elongated fibrils — the perfect material for building the cell walls of plants. Chile Slide 8: Chile Slide 9: This electron micrograph shows the cellulose fibrils in the cell wall of a green alga. These long, rigid fibrils are a clear reflection of the nature of the cellulose molecules of which they are composed. Chile Cellulolytic enzymes : Cellulolytic enzymes Comparatively little is known about the role of Cellulases in the tissue degradation during pathogenesis. Not all the pathogenic fungi are Cellulolytic although they do cause tissue disintegration. A team of C1 enzyme, Cx enzymes and ß-glycosidase is suggested to be involved during pathogenesis. Chile Slide 11: Chile Slide 12: Chile Pectic enzymes : Pectic enzymes Pectic substances or pectin are major component of middle lamella which binds the cells together. Pathogens like fungi, bacteria and nematodes are known to produce Pectic or Pectinolytic enzymes. Pectic substances are polymers a 1?4 linked galacturonic acid units. Chile Slide 14: Carboxylic group at 6 th position is intact in Polygalacturonic acid which in state can be referred to as Pectic acid. Carboxylic group are esterified with methyl groups gives rise to Pectinic acid. Pectin are Pectinic acids of high methoxy content or more of methylated carboxyl groups. Chile Slide 15: Pectic substances are degraded by Polygalacturonases (PG), Exo and Endo. Pectinmethylgalacturonases (PMG), Exo and Endo. Pectinesterases or Pectinmethylesterases (PME) Polygalacturonase Transeliminases (PGT) Chile Slide 16: Chile Slide 17: Chile Slide 18: Polygalacturonases (PG), Exo and Endo. Exo PG and Endo PG hydrolytically break the Pectic acid respectively acting on the terminals and mid part of the polymer. Pectinmethylgalacturonases (PMG), Exo and Endo. Exo and Endo PMG also act in a similar manner. Chile Slide 19: Pectinesterases or Pectinmethylesterases (PME) PME hydrolyses and breaks the ester linkage, thus coverts Pectinic acid to Pectic acid the later is ultimately degraded by PG enzyme. PME Chile Slide 20: Polygalacturonase Transeliminases (PGT) PGT breaks the polymer by a nonhydrolytic method thus releasing unsaturated sugars. Unsaturated Sugars released after Lyase activity Chile Slide 21: These enzymes are primarily produced by soft rot pathogens such as Erwinia dissolvens, E. carotovara, Pseudomonas spp., Botrytis cinerea, Sclerotinia sclerotiorum, Sclerotium rolfsi, Rhizoctonia solani, species of Pythium, Phytophthora and Rhizopus. Specialized pathogen like Puccinia graminis tritici also produces Pectic enzymes during spore germination. Chile Slide 22: Role of Hemicellulases, Lignolytic enzymes, Amylase, Proteases and Lipases :- Not very significant. Wood rotters are known to produce Lignolytic and Cellulolytic enzymes during brown rot and white rot pathogenesis. Some filamentous fungi are also known to break down lignin. Chile You do not have the permission to view this presentation. In order to view it, please contact the author of the presentation.
Cell wall degrading enzymes chilesatish Download Post to : URL : Related Presentations : Share Add to Flag Embed Email Send to Blogs and Networks Add to Channel Uploaded from authorPOINT lite Insert YouTube videos in PowerPont slides with aS Desktop Copy embed code: (To copy code, click on the text box) Embed: URL: Thumbnail: WordPress Embed Customize Embed The presentation is successfully added In Your Favorites. Views: 1832 Category: Science & Tech.. License: All Rights Reserved Like it (1) Dislike it (0) Added: April 21, 2009 This Presentation is Public Favorites: 0 Presentation Description Cell wall degrading enzymes play a key role in the development on plant diseases caused by plant pathogens. Comments Posting comment... By: framsis2nd (32 month(s) ago) Nice Saving..... Post Reply Close Saving..... Edit Comment Close Premium member Presentation Transcript Cell wall degrading enzymes : Cell wall degrading enzymes These are macerating factors. These includes; 1. Cellulases 2. Pectinases 3. Hemicelluloses 4. Proteases 5. Cutinases 6. Lignases Chile Slide 2: Chile Cuticular enzymes : Cuticular enzymes The major chemical substances in cuticle is a cutin framework with waxes embedded in it and extruded from its surface to give a water proof surface (the Cuticular wax). Cutin is a polyester of hydroxylated monocarboxylic acids ( with 16 to 18 carbons and 2 to 3 hydroxyl groups.) Wax contains complex mixture of long chains paraffin, alcohols, ketones, esters and acids. Chile Slide 4: Role of enzymes in the dissolution of cuticle is not very well understood. Various enzymes have been suggested in dissolution of cuticle; Cutinesterases Cutinases Lipases A mixture of enzymes includes protease. Cellulases and Pectinases etc.( Germinating spores of Colletotrichum gloeosprioides on orange leaves, Spaerothece pannosa on Rose leaves, Venturia inaequalis on Apple, and Helminthosporium victoriae. Chile Cellulose : Cellulose Cellulose is probably the single most abundant organic molecule in the biosphere. It is the major structural material of which plants are made. Wood is largely cellulose while cotton and paper are almost pure cellulose. Chile Slide 6: Because of the orientation of the glycosidic bonds linking the glucose residues, the rings of glucose are arranged in a flip-flop manner. This produces a long, straight, rigid molecule. There are no side chains in cellulose as there are in starch. The absence of side chains allows these linear molecules to lie close together. Chile Slide 7: Because of the many -OH groups, as well as the oxygen atom in the ring, there are many opportunities for hydrogen bonds to form between adjacent chains. The result is a series of stiff, elongated fibrils — the perfect material for building the cell walls of plants. Chile Slide 8: Chile Slide 9: This electron micrograph shows the cellulose fibrils in the cell wall of a green alga. These long, rigid fibrils are a clear reflection of the nature of the cellulose molecules of which they are composed. Chile Cellulolytic enzymes : Cellulolytic enzymes Comparatively little is known about the role of Cellulases in the tissue degradation during pathogenesis. Not all the pathogenic fungi are Cellulolytic although they do cause tissue disintegration. A team of C1 enzyme, Cx enzymes and ß-glycosidase is suggested to be involved during pathogenesis. Chile Slide 11: Chile Slide 12: Chile Pectic enzymes : Pectic enzymes Pectic substances or pectin are major component of middle lamella which binds the cells together. Pathogens like fungi, bacteria and nematodes are known to produce Pectic or Pectinolytic enzymes. Pectic substances are polymers a 1?4 linked galacturonic acid units. Chile Slide 14: Carboxylic group at 6 th position is intact in Polygalacturonic acid which in state can be referred to as Pectic acid. Carboxylic group are esterified with methyl groups gives rise to Pectinic acid. Pectin are Pectinic acids of high methoxy content or more of methylated carboxyl groups. Chile Slide 15: Pectic substances are degraded by Polygalacturonases (PG), Exo and Endo. Pectinmethylgalacturonases (PMG), Exo and Endo. Pectinesterases or Pectinmethylesterases (PME) Polygalacturonase Transeliminases (PGT) Chile Slide 16: Chile Slide 17: Chile Slide 18: Polygalacturonases (PG), Exo and Endo. Exo PG and Endo PG hydrolytically break the Pectic acid respectively acting on the terminals and mid part of the polymer. Pectinmethylgalacturonases (PMG), Exo and Endo. Exo and Endo PMG also act in a similar manner. Chile Slide 19: Pectinesterases or Pectinmethylesterases (PME) PME hydrolyses and breaks the ester linkage, thus coverts Pectinic acid to Pectic acid the later is ultimately degraded by PG enzyme. PME Chile Slide 20: Polygalacturonase Transeliminases (PGT) PGT breaks the polymer by a nonhydrolytic method thus releasing unsaturated sugars. Unsaturated Sugars released after Lyase activity Chile Slide 21: These enzymes are primarily produced by soft rot pathogens such as Erwinia dissolvens, E. carotovara, Pseudomonas spp., Botrytis cinerea, Sclerotinia sclerotiorum, Sclerotium rolfsi, Rhizoctonia solani, species of Pythium, Phytophthora and Rhizopus. Specialized pathogen like Puccinia graminis tritici also produces Pectic enzymes during spore germination. Chile Slide 22: Role of Hemicellulases, Lignolytic enzymes, Amylase, Proteases and Lipases :- Not very significant. Wood rotters are known to produce Lignolytic and Cellulolytic enzymes during brown rot and white rot pathogenesis. Some filamentous fungi are also known to break down lignin. Chile