Abstract
The microscopic kinetics of enzymes at the single-molecule level often deviate considerably from those expected from bulk biochemical experiments. Here, we propose a coarse-grained-model approach to bridge this gap, focusing on the unexpectedly slow bulk hydrolysis of crystalline cellulose by cellulase, which constitutes a major obstacle to mass production of biofuels and biochemicals. Building on our previous success in tracking the movements of single molecules of cellulase on crystalline cellulose, we develop a mathematical description of the collective motion and function of enzyme molecules hydrolyzing the surface of cellulose. Model simulations robustly explained the experimental findings at both the microscopic and macroscopic levels and revealed a hitherto-unknown mechanism causing a considerable slowdown of the reaction, which we call the crowding-out effect. The size of the cellulase molecule impacted significantly on the collective dynamics, whereas the rate of molecular motion on the surface did not.
| Original language | English |
|---|---|
| Article number | 098102 |
| Number of pages | 5 |
| Journal | Physical Review Letters |
| Volume | 122 |
| Issue number | 9 |
| DOIs | |
| Publication status | Published - 7 Mar 2019 |
| MoE publication type | A1 Journal article-refereed |
Funding
This research was partially supported by Grant-in-Aid for Innovative Areas from the Japanese Ministry of Education, Culture, Sports, and Technology (MEXT) (No. 24114001, No. 24114008, and No. 18H05494), Impulsing Paradigm Change through Disruptive Technologies (ImPACT) from the Japan Science and Technology Agency (JST), and Asahi Glass Foundation to K. I. K. I. thanks the Finnish Funding Agency for Innovation (TEKES) for the support of the Finland Distinguished Professor (FiDiPro) Program “Advanced approaches for enzymatic biomass utilisation and modification (BioAD).”
Keywords
- Biochemistry
- Biomolecular processes
- Chemical kinetics
