| Value |
4.7
molecules/min/26S
Range: Table - link molecules/min/26S
|
| Organism |
Mammals |
| Reference |
Peth A, Nathan JA, Goldberg AL. The ATP costs and time required to degrade ubiquitinated proteins by the 26 S proteasome. J Biol Chem. 2013 Oct 4 288(40):29215-22. doi: 10.1074/jbc.M113.482570 p.29219 Table 1PubMed ID23965995
|
| Method |
"Initial experiments used 26S proteasomes gently
isolated from yeast (ref 16) to determine whether they
hydrolyze ATP by a stochastic or a highly
cooperative manner, such as the cyclical, ordered
mechanism proposed recently in which nucleotides
bind and exchange in pairs (ref 13)." "Vmax values were calculated as shown in Fig. 3. The time to degrade one substrate molecule/26 S proteome is calculated as 1/Vmax. The presence of folic acid slowed Ub5-DHFR degradation down to 57% of the control, as shown in Fig. 4." |
| Comments |
"All ubiquitinated proteins used in this study that can be degraded by the 26 S proteasome stimulate ATP hydrolysis by 2–3-fold, which implies that 240–360 molecules are consumed per min during degradation of DHFR or Sic1 (Table 1). Thus, at Vmax, the cost of ATP per molecule of Ub5-DHFR degraded appears to be 50–80 ATPs, whereas breakdown of Ubn-Sic1 requires 100–160 ATPs (Table 1). Interestingly, Sic1 is almost twice the length of DHFR. Therefore, it is tempting to conclude that longer polypeptides require more time and more ATP to be degraded by the 26 S proteasome." With folic acid added Vmax is 2.7 molecules/min/26S |
| Entered by |
Uri M |
| ID |
109854 |