Abstract：
:Molecular motors are thought to generate force and directional motion via nonequilibrium switching between energy surfaces. Because all enzymes can undergo such switching, we hypothesized that the ability to generate rotary motion and torque is not unique to highly adapted biological motor proteins but is instead a common feature of enzymes. We used molecular dynamics simulations to compute energy surfaces for hundreds of torsions in three enzymes-adenosine kinase, protein kinase A, and HIV-1 protease-and used these energy surfaces within a kinetic model that accounts for intersurface switching and intrasurface probability flows. When substrate is out of equilibrium with product, we find computed torsion rotation rates up ∼140 cycles s-1, with stall torques up to ∼2 kcal mol-1 cycle-1, and power outputs up to ∼50 kcal mol-1 s-1. We argue that these enzymes are instances of a general phenomenon of directional probability flows on asymmetric energy surfaces for systems out of equilibrium. Thus, we conjecture that cyclic probability fluxes, corresponding to rotations of torsions and higher-order collective variables, exist in any chiral molecule driven between states in a nonequilibrium manner; we call this the "Asymmetry-Directionality" conjecture. This is expected to apply as well to synthetic chiral molecules switched in a nonequilibrium manner between energy surfaces by light, redox chemistry, or catalysis.
journal_name
Biophys Jjournal_title
Biophysical journalauthors
Slochower DR,Gilson MKdoi
10.1016/j.bpj.2018.02.008subject
Has Abstractpub_date
2018-05-08 00:00:00pages
2174-2179issue
9eissn
0006-3495issn
1542-0086pii
S0006-3495(18)30211-Xjournal_volume
114pub_type
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journal_title：Biophysical journal
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journal_title：Biophysical journal
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journal_title：Biophysical journal
pub_type： 杂志文章,评审
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journal_title：Biophysical journal
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journal_title：Biophysical journal
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journal_title：Biophysical journal
pub_type： 杂志文章
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journal_title：Biophysical journal
pub_type： 杂志文章
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doi：10.1016/j.bpj.2011.08.007
更新日期：2011-09-21 00:00:00
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journal_title：Biophysical journal
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