Chemistry Reference
In-Depth Information
A
N
ucleophilic residue (As
p)
δ
δ
O
O
O
O
O
-
O
O
-
O
O
O
O
R
2
OH
R
1
OH
O
O
O
O
O
glucosylation
deglucosylation
R
O
O
R
R
O
δ
δ
H
OR
H
OR
H
-
O
HO
O
O
O
O
O
O
HO
O
Acidic/basic residue (Glu)
Transition state
Covalent β-D-glucosyl enzyme
Transition state
R
1
= Fructose
R
2
= H : Hydrolysis
R
2
= Carbohydrate : Transglucosylation
R
2
= Fructose : Sucrose isomerization
B
GH13 product
Hydrolysis
α1-4
α1-4
α1-4
α1-4
α1-4
Amylose
Polymerization
GH70 products
Oligosaccharides
α1-6
α1-3
α1-6
α1-3
α1-6
Alternan
n
α(1-2)β
α1-6
α1-6
α1-6
α1-6
α1-6
Dextran
Acceptor reactions
Sucrose
Sucrose
n
α1-3
α1-3
α1-3
α1-3
α1-3
Mutan
n
α1-4
α1-6
α1-4
α1-6
α1-4
Reuteran
α1-1
n
Trehalulose
α1-2
α1-3
Glucoconjugates
α1-6
α1-6
α1-6
α1-6
α1-6
Turanose
α-1,2 branched glucan
n
α1-2
α1-5
Leucrose
Sucrose isomerization
Glucose
Fructose
Monosaccharide
Non-saccharidic acceptor
Fig. 1 Reactions catalyzed by glucansucrases. (A) General mechanism; (B) Overview of the products generated by glucansucrases.
Search WWH ::
Custom Search