Sandbox Reserved 655: Difference between revisions

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~~Beta-1,4-Endoglucanase is a specific enzyme that catalyzes the hydrolysis of cellulose. It is produced chiefly by fungi, bacteria, and protozoans.~~ Cellulose is one of the main components of the plant cell wall, found predominantly in the xylem tissue which is further protected by hemicellulose and pectin. ~~Beta-1~~,4-~~glycosidic bonds~~ (~~hence~~ the ~~name~~, ~~beta~~-1,4-~~endoglucanase)~~ link together the beta-D-glucopyranose units of cellulose. Beta-1-4-endoglucanase enzymes specifically cleave the internal bonds of the cellulose chain.

Cellulose is one of the main components of the plant cell wall, found predominantly in the xylem tissue which is further protected by hemicellulose and pectin. Cellulases are enzymes that catalyze the hydrolysis of cellulose and belong to a group of enzymes termed glycoside hydrolases (GHs). Several members of the GH family demonstrate a modular architecture composed of one or two catalytic modules connected to several kinds of accessory modules (Schubot et al., 2004). The accessory modules can be involved in numerous functions. For example, some cellulases contain carbohydrate-binding modules (CBMs), which enhance the association of the catalytic modules with insoluble carbohydrates. Cellulases have been characterized as endo or exo according to their mode of action on the substrate (Parsiegla et al., 2002). The endocellulases cleave the cellulose chain at arbitrary points, while exocellulases cleave at the terminus of a chain to start the degradation process.Beta-1,4-glycosidic bonds link together the beta-D-glucopyranose units of cellulose. Beta-1-4-endoglucanase enzymes produced chiefly by fungi; bacteria and protozoans, specifically cleave the internal bonds of the cellulose chain.

In the past 20 years, researchers have found that endoglucanases cannot break down polysaccharides efficiently without the help of non-catalytic carbohydrate-binding modules. Thus, endoglucanase is mostly found in the form of a complex that is made up of three separate domains. The main domain contains the large, globular catalytic domain which expresses the active site. A loop of the protein chain forms a tunnel that encloses the active site. This is attached at the O-glycosylated B block hinge region of the catalytic domain to the smaller, globular CBM at its C-terminal A block by a linker peptide made up of proline, serine, and threonine (Nimlos, et al., 2007)

== '''Structure''' ==

In the past 20 years, researchers have found that endoglucanases cannot break down polysaccharides efficiently without the help of non-catalytic carbohydrate-binding modules. Thus, endoglucanase is mostly found in the form of a complex that is made up of three separate domains. The main domain contains the large, globular catalytic domain which expresses the active site. A loop of the protein chain forms a tunnel that encloses the active site. This is attached at the O-glycosylated B block hinge region of the catalytic domain to the smaller, globular CBM at its C-terminal A block by a linker peptide made up of proline, serine, and threonine (Nimlos, et al., 2007).

~~Today, one of the primary research uses for glutamate dehydrogenase is to determine how well the human liver is functioning. If the level of GDH is too high that could indicate necrosis of the liver~~. ~~(7)~~

~~== '''Structure''' ==~~

Glutamate Dehydrogenase is a hexamer that is comprised of two trimer subunits. These two subunits are stacked on top of each other and composed of three domains. The top of each domain contains a "NAD-binding domain" that has the conserved nucleotide-binding motif. A larger helix-loop-helix structure rises above this and is referred to as an "antenna." This antenna contains approximately 50 amino acids and is thought to play a major role in regulation of the enzyme. This antennae structure is only found in animals. (1) The bottom domain contacts a domain in the other trimer, holding the two trimers together. The total size of each of the subunits is approximately 56.1 kD and 506 amino acids long. (5)

Sandbox Reserved 655: Difference between revisions

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 <Structure load='1clc' size='500' frame='true' align='right' caption='Beta-1,4-Endoglucanase' scene='Insert optional scene name here' />
-Beta-1,4-Endoglucanase is a specific enzyme that catalyzes the hydrolysis of cellulose. It is produced chiefly by fungi, bacteria, and protozoans. Cellulose is one of the main components of the plant cell wall, found predominantly in the xylem tissue which is further protected by hemicellulose and pectin. Beta-1,4-glycosidic bonds (hence the name, beta-1,4-endoglucanase) link together the beta-D-glucopyranose units of cellulose. Beta-1-4-endoglucanase enzymes specifically cleave the internal bonds of the cellulose chain.
+Cellulose is one of the main components of the plant cell wall, found predominantly in the xylem tissue which is further protected by hemicellulose and pectin. Cellulases are enzymes that catalyze the hydrolysis of cellulose and belong to a group of enzymes termed glycoside hydrolases (GHs). Several members of the GH family demonstrate a modular architecture composed of one or two catalytic modules connected to several kinds of accessory modules (Schubot et al., 2004). The accessory modules can be involved in numerous functions. For example, some cellulases contain carbohydrate-binding modules (CBMs), which enhance the association of the catalytic modules with insoluble carbohydrates. Cellulases have been characterized as endo or exo according to their mode of action on the substrate (Parsiegla et al., 2002). The endocellulases cleave the cellulose chain at arbitrary points, while exocellulases cleave at the terminus of a chain to start the degradation process.Beta-1,4-glycosidic bonds link together the beta-D-glucopyranose units of cellulose. Beta-1-4-endoglucanase enzymes produced chiefly by fungi; bacteria and protozoans, specifically cleave the internal bonds of the cellulose chain.
-In the past 20 years, researchers have found that endoglucanases cannot break down polysaccharides efficiently without the help of non-catalytic carbohydrate-binding modules. Thus, endoglucanase is mostly found in the form of a complex that is made up of three separate domains. The main domain contains the large, globular catalytic domain which expresses the active site. A loop of the protein chain forms a tunnel that encloses the active site. This is attached at the O-glycosylated B block hinge region of the catalytic domain to the smaller, globular CBM at its C-terminal A block by a linker peptide made up of proline, serine, and threonine (Nimlos, et al., 2007)
+== '''Structure''' ==
+In the past 20 years, researchers have found that endoglucanases cannot break down polysaccharides efficiently without the help of non-catalytic carbohydrate-binding modules. Thus, endoglucanase is mostly found in the form of a complex that is made up of three separate domains. The main domain contains the large, globular catalytic domain which expresses the active site. A loop of the protein chain forms a tunnel that encloses the active site. This is attached at the O-glycosylated B block hinge region of the catalytic domain to the smaller, globular CBM at its C-terminal A block by a linker peptide made up of proline, serine, and threonine (Nimlos, et al., 2007).
-Today, one of the primary research uses for glutamate dehydrogenase is to determine how well the human liver is functioning.  If the level of GDH is too high that could indicate necrosis of the liver. (7)
-== '''Structure''' ==
 Glutamate Dehydrogenase is a hexamer that is comprised of two trimer subunits.  These two subunits are stacked on top of each other and composed of three domains.  The top of each domain contains a "NAD-binding domain" that has the conserved nucleotide-binding motif.  A larger helix-loop-helix structure rises above this and is referred to as an "antenna."  This antenna contains approximately 50 amino acids and is thought to play a major role in regulation of the enzyme.  This antennae structure is only found in animals. (1)  The bottom domain contacts a domain in the other trimer, holding the two trimers together.  The total size of each of the subunits is approximately 56.1 kD and 506 amino acids long. (5)