Literature summary for 3.2.1.70 extracted from

Hondoh, H.; Saburi, W.; Mori, H.; Okuyama, M.; Nakada, T.; Matsuura, Y.; Kimura, A.
Substrate recognition mechanism of alpha-1,6-glucosidic linkage hydrolyzing enzyme, dextran glucosidase from Streptococcus mutans (2008), J. Mol. Biol., 378, 913-922.

Cloned(Commentary)

Cloned (Comment)	Organism
wild-type and mutant expressed in Escherichia coli BL21 (DE3) CodonPlus RIL containing the expression plasmid derived from pET23d	Streptococcus mutans

Crystallization (Commentary)

Crystallization (Comment)	Organism
crystal structures of DGase in uncomplexed form and a mutant in complex with isomaltotriose, to 2.2 A resolution, by the hanging-drop, vapor-diffusion method at 20°C. The enzyme is composed of three domains, A, B and C, and has a (beta/alpha)8-barrel in domain A. Three catalytic residues are located at the bottom of the active site pocket and the bound isomaltotriose occupies subsites -1 to +2. Hydrogen bonds between Asp60 and Arg398 and O4 atom of the glucose unit at subsite -1 accomplish recognition of the non-reducing end of the bound substrate. The side-chain atoms of Glu371 and Lys275 form hydrogen bonds with the O2 and O3 atoms of the glucose residue at subsite +1	Streptococcus mutans

Crystallization (Comment)

Organism

crystal structures of DGase in uncomplexed form and a mutant in complex with isomaltotriose, to 2.2 A resolution, by the hanging-drop, vapor-diffusion method at 20°C. The enzyme is composed of three domains, A, B and C, and has a (beta/alpha)8-barrel in domain A. Three catalytic residues are located at the bottom of the active site pocket and the bound isomaltotriose occupies subsites -1 to +2. Hydrogen bonds between Asp60 and Arg398 and O4 atom of the glucose unit at subsite -1 accomplish recognition of the non-reducing end of the bound substrate. The side-chain atoms of Glu371 and Lys275 form hydrogen bonds with the O2 and O3 atoms of the glucose residue at subsite +1

Streptococcus mutans

Protein Variants

Protein Variants	Comment	Organism
E236Q	catalysis is compromised in complex with isomaltotriose	Streptococcus mutans

Metals/Ions

Metals/Ions	Comment	Organism	Structure
Ca2+	-	Streptococcus mutans

Molecular Weight [Da]

Molecular Weight [Da]	Molecular Weight Maximum [Da]	Comment	Organism
62000	-	-	Streptococcus mutans

Organism

Organism	UniProt	Comment	Textmining
Streptococcus mutans	Q99040	-	-

Purification (Commentary)

Purification (Comment)	Organism
by Ni-chelating column chromatography	Streptococcus mutans

Substrates and Products (Substrate)

Substrates	Comment Substrates	Organism	Products	Comment (Products)	Rev.	Reac.
isomaltotriose + H2O	-	Streptococcus mutans	D-glucose	-	?

Synonyms

Synonyms	Comment	Organism
dextran glucosidase	-	Streptococcus mutans
DGase	-	Streptococcus mutans