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The depth of chemical time and the power of enzymes as catalysts.

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TLDR
Thermodynamic comparisons between spontaneous and enzyme-catalyzed reactions, coupled with structural information, suggest that in addition to electrostatic and H-bonding interactions, the liberation of water molecules from an enzyme's active site into bulk solvent sometimes plays a prominent role in determining the relative binding affinities of the altered substrate in the ground state and transition state.
Abstract
The fastest known reactions include reactions catalyzed by enzymes, but the rate enhancements that enzymes produce had not been fully appreciated until recently. In the absence of enzymes, these same reactions are among the slowest that have ever been measured, some with half-times approaching the age of the Earth. This difference provides a measure of the proficiencies of enzymes as catalysts and their relative susceptibilities to inhibition by transition-state analogue inhibitors. Thermodynamic comparisons between spontaneous and enzyme-catalyzed reactions, coupled with structural information, suggest that in addition to electrostatic and H-bonding interactions, the liberation of water molecules from an enzyme's active site into bulk solvent sometimes plays a prominent role in determining the relative binding affinities of the altered substrate in the ground state and transition state. These comparisons also indicate a high level of synergism in the action of binding determinants of both the substrate a...

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Citations
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Outlook for cellulase improvement: screening and selection strategies.

TL;DR: In this paper, the authors review quantitative cellulase activity assays using soluble and insoluble substrates, and focus on their advantages and limitations, and hypothesize that continuous culture using insoluble cellulosic substrates could be a powerful selection tool for enriching beneficial cellulase mutants from the large library displayed on the cell surface.
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How Enzymes Work: Analysis by Modern Rate Theory and Computer Simulations

TL;DR: A framework for understanding the effects of lowering of the activation free energy and changes in the generalized transmission coefficient on enzyme catalysis is presented, and the contributions of the different factors are identified and quantified by computer simulations.
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Irreversible inhibitors of serine, cysteine, and threonine proteases.

TL;DR: This paper presents a meta-review of the literature on Vinyl Sulfones, Michael Acceptors, and Heterocyclic Inhibitors dating back to the 1970s, which revealed a wide diversity of opinions about the properties of these substances and their role in the human immune system.
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Molecular dynamics and protein function

TL;DR: Two areas, protein folding and enzymatic catalysis, are surveyed, in which simulations have contributed to a general understanding of mechanism.
References
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Journal ArticleDOI

The Structural Basis of Ribosome Activity in Peptide Bond Synthesis

TL;DR: It is established that the ribosome is a ribozyme and the catalytic properties of its all-RNA active site are addressed and the mechanism of peptide bond synthesis appears to resemble the reverse of the acylation step in serine proteases.
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Magnetic vortex core observation in circular dots of permalloy

TL;DR: Experimental evidence for a spot of perpendicular magnetization at the center of the vortex is provided by magnetic force microscopy imaging of circular dots of permalloy (Ni(80)Fe(20)) 0.3 to 1 micrometer in diameter and 50 nanometers thick.
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Entropic contributions to rate accelerations in enzymic and intramolecular reactions and the chelate effect.

TL;DR: It is pointed out that translational and (overall) rotational motions provide the important entropic driving force for enzymic and intramolecular rate accelerations and the chelate effect; internal rotations and unusually severe orientational requirements are generally of secondary importance.
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On the attribution and additivity of binding energies.

TL;DR: It can be useful to describe the Gibbs free energy changes for the binding to a protein of a molecule and of its component parts in terms of the "intrinsic binding energies" of A and B, DeltaG(A) (i) and DeltaG (i), and a "connection Gibbs energy" that is derived largely from changes in translational and rotational entropy.
Journal ArticleDOI

A proficient enzyme

TL;DR: Values of the known range of spontaneous rate constants for reactions that are also susceptible to catalysis by enzymes are extended to more than 14 orders of magnitude, in contrast to previous work.
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