Sandbox Reserved 301: Difference between revisions
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=Family= | =Family= | ||
E. coli Branching enzyme belongs to the a-amylase family of enzymes. Members of this group include a-amylase, pullulanase/isoamylase, cyclodextrin glucanotransferase (CGT), and branching enzymes. Analyzing X-ray structres of a-amylase, isoamylase, CGT with the branching enzyme show that these enzymes have a common (a/b) barrel domain that contains the enzyme's catalytic centre. | E. coli Branching enzyme belongs to the a-amylase family of enzymes. Members of this group include a-amylase, pullulanase/isoamylase, cyclodextrin glucanotransferase (CGT), and branching enzymes. Analyzing X-ray structres of a-amylase, isoamylase, CGT with the branching enzyme show that these enzymes have a common (a/b) barrel domain that contains the enzyme's catalytic centre. | ||
<Structure load='1m7x' size='500' frame='true' align='right' caption='Insert caption here' scene='Insert optional scene name here' /> | <Structure load='1m7x' size='500' frame='true' align='right' caption='Insert caption here' scene='Insert optional scene name here' /> | ||
=Domains= | =Domains= | ||
Braching enzyme is divided in three domains based on the prediction of secondary structure and smiliarities of amylotic family of enzymes. The three domains consist of an amino-terminal domain, a carboxyl-terminal domain, and a central (a/b) barrel catalytic domain. | Braching enzyme is divided in three domains based on the prediction of secondary structure and smiliarities of amylotic family of enzymes. The three domains consist of an amino-terminal domain, a carboxyl-terminal domain, and a central (a/b) barrel catalytic domain. | ||
==Amino-Terminal Domain== | ==Amino-Terminal Domain== | ||
The NH2-terminal domain is involved in determining the size of the chain transferred. This domain helps determine the unique feature of the action of the branching enzyme lies to the specificity for the length of the glucan chain transferred. E. coli Branching Enzyme prefers to transfer shorter chains between 5 and 16 glucose units. | |||
==Carboxyl-Terminal Domain== | ==Carboxyl-Terminal Domain== | ||
The COOH-terminal domain is involved in substrate preference and catalytic capacity. | |||
==Central (a/b) Barrel Catalytic Domain== | ==Central (a/b) Barrel Catalytic Domain== | ||
Based on analysis of biochemical and X-Ray structures of apo- (without a substrate bound) and substrate-bound a-amylase and CGT, the catalytic center of of these enzymes have been localized to the residues Tyr300, Asp335, His340, Arg403, Asp405, Glu458, and Asp526 in the E. ''coli'' as shown in <scene name='Sandbox_Reserved_301/Gbe1/2'>Conserved Area</scene>. | |||
=References= | =References= | ||
<references/> | <references/> | ||
[http://www.wikipedia.org E.ColiBranchingEnzyme] | [http://www.wikipedia.org E.ColiBranchingEnzyme] | ||
