3p0b
From Proteopedia
m (Protected "3p0b" [edit=sysop:move=sysop]) |
Revision as of 08:29, 2 May 2013
Thermus thermophilus family GH57 branching enzyme: crystal structure, mechanism of action and products formed
Template:ABSTRACT PUBMED 021097495
Function
[P84162_THETH] Catalyzes the formation of branch points in alpha-glucans by cleavage of an alpha-1,4 glycosidic bond and subsequent transfer of the cleaved-off oligosaccharide to a new alpha-1,6 position. The branch chain-length distribution of the reaction products shows degree of polymerization (DP) of 3 to 13, with two local maxima at DP 7 and DP 11. Exhibits an alpha-retaining catalytic mechanism. Is involved in glycogen biosynthesis. Shows a secondary activity, i.e. the hydrolysis of the substrate, being 4% of the total activity. Can use amylose as substrate but not alpha-1,4-linked oligosaccharides of 2-7 glucose residues, beta-cyclodextrin, 6-O-glucosyl-beta-cyclodextrin and 6-O-maltosyl-beta-cyclodextrin. Is not able to branch amylopectin further, it only hydrolyzes amylopectin. Thus, displays preference for linear and long substrates (amylose) over branched structures (amylopectin).
About this Structure
3p0b is a 1 chain structure with sequence from Thermus thermophilus. Full crystallographic information is available from OCA.
