Glycogen synthase
Glycogen synthase (GS) converts glucose to glycogen. It takes short polymers of glucose and converts them into long polymers one by one into a polymeric chain for storage as glycogen.
Contents
Chemical equation
Rate equation
MWC model (Monod-Wyman-Changeux model) is used to model the reaction mechanism of this enzyme.[1]. Glc6P activates GS by binding to an allosteric site of this enzyme.
Parameter values
Parameter | Value | Units | Organism | Remarks |
---|---|---|---|---|
4 [1] | Dimensionless | Rabbit muscle | ||
1004 [1] | Rabbit muscle | |||
Total[GS] | [1] | mM | ||
L | 0.25 [1] | Dimensionless | ||
0.72[1] | mM | Rat muscle | ||
[1] | mM | Rat muscle | ||
0.29[1] | mM | Rat muscle | ||
4.94[1] | mM | Rat muscle | ||
2.33[1] | mM | Rat muscle | ||
15.92[1] | mM | Rat muscle | ||
3.93[1] | mM | Rat muscle |
Parameters with uncertainty
- The parameter values with their uncertainty are mentioned in Table 3.5: Optimized kinetic parameters obtained using a scaled weighting strategy for data obtained by varying UDPG and a half-scaled strategy for data obtained by varying G6P [1].
- n is the number of allosteric active site which is constant.
- Total[GS] also considers to be constant as it represents the total concentration of enzymes.
- The value of L is calculated based on the activity ratio of the enzyme (The activity ratio is defined as the ratio of activity in the absence of glucose-6-P to that in its presence). The activity ratio for L is mentioned as to be in between in Wang (1993) et. al.[2]. The Std. Dev. for this measurement is 0.025 which is 25% of the mean value. The same percent of error is considered for the value of L.
- Maximum error for all Km values listed for GS was 38%. For this percent of error are considered.
Parameter | Value | Units | Organism | Remarks |
---|---|---|---|---|
4 [1] | Dimensionless | Rabbit muscle | ||
Rabbit muscle | ||||
Total[GS] | [1] | mM | ||
L | [1] | Dimensionless | ||
mM | Rat muscle | |||
mM | Rat muscle | |||
mM | Rat muscle | |||
mM | Rat muscle | |||
mM | Rat muscle | |||
mM | Rat muscle | |||
mM | Rat muscle |
References
- ↑ 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 1.12 1.13 1.14 1.15 Palm, D.C. (2013). The regulatory design of glycogen metabolism in mammalian skeletal muscle (Ph.D.). University of Stellenbosch
- ↑ Wang Y & Roach PJ (1993) Inactivation of rabbit muscle glycogen synthase by glycogen synthase kinase-3. Dominant role of the phosphorylation of Ser-640 (site-3a). J Biol Chem 268, 23876–23880