1) Draw Haworth Structures for the following:
b) a-D-fructopyranose
c) b-D-glucopyranose
d) b-D-glucofuranose
e) b-L-glucofuranose
f) a-D-galactopyranose
g) a-D-xylofuranose
h) b-D-galactopyranosyl- (1,4) a-D-glucopyranose
i) a-D-glucopyransyl-(1,6) b-D-glucopyranose
j ) a-D-glucopyranosyl b-D-glucopyranoside
3) Draw a Haworth projection for the disaccharide gentibiose, given the following information: 1) It is a dimer of glucose.2) The glycosidic linkage is b(1->6) 3). The anomeric carbon not involved in the glycosidic linkage is in the a configuration.
4) How does chitin differ from cellulose in structure and function?
5) How does glycogen differ from starch in structure and function?
6) Hexokinase is an enzyme that catalyzes the transfer of a phosphoryl group from ATP to glucose, fructose, or mannose, forming ADP and glucose 6-phosphate, fructose 6-phosphate, and mannose 6-phosphate, respectively. N-acetylglucosamine is a competitive inhibitor of hexokinase-catalyzed phosphorylation of all of these sugars.
b) Draw Haworth projections for the a anomers of the three phosphorylated hexose products of hexokinase-catalyzed phosphoryl transfer from ATP (glucose 6-phosphate, fructose 6-phosphate, and mannose 6-phosphate).
c) Based on the four hexoses in (a), what conclusions can be drawn regarding
the substrate specificity of hexokinase and inhibition of the enzyme by
N-acetylglucosamine?
b) ATP + glycerol ---> Glycerol 3-phosphate + ADP
c) ATP + pyruvate ---> phosphoenolpyruvate + ADP
d) ATP + glucose ---> glucose 6-phosphate + ADP
is +0.4 kcal mol-1. From this information and that in Table 11.3, calculate te change in standard free energy for the reaction:
Compound |
|
|
Phosphoenolpyruvate |
|
|
Carbamoyl Phosphate |
|
|
1,3 Bis phosphoglycerate |
|
|
Creatine Phosphate |
|
|
Pyrophosphate (PPi) |
|
|
ATP (to ADP) |
|
|
Glucose 1-phosphate |
|
|
Glucose 3-phosphate |
|
|
Glycerol 3-phosphate |
|
|
Problem #1