Journal
BIOPHYSICAL JOURNAL
Volume 99, Issue 8, Pages L62-L64Publisher
CELL PRESS
DOI: 10.1016/j.bpj.2010.07.066
Keywords
-
Categories
Funding
- Oak Ridge National Laboratory under United States Department of Energy
Ask authors/readers for more resources
Water is widely assumed to be essential for life, although the exact molecular basis of this requirement is unclear. Water facilitates protein motions, and although enzyme activity has been demonstrated at low hydrations in organic solvents, such nonaqueous solvents may allow the necessary motions for catalysis. To examine enzyme function in the absence of solvation and bypass diffusional constraints we have tested the ability of an enzyme, pig liver esterase, to catalyze alcoholysis as an anhydrous powder, in a reaction system of defined water content and where the substrates and products are gaseous. At hydrations of 3 (+/- 2) molecules of water per molecule of enzyme, activity is several orders-of-magnitude greater than nonenzymatic catalysis. Neutron spectroscopy indicates that the fast (<= nanosecond) global anharmonic dynamics of the anhydrous functional enzyme are suppressed. This indicates that neither hydration water nor fast anharmonic dynamics are required for catalysis by this enzyme, implying that one of the biological requirements of water may lie with its role as a diffusion medium rather than any of its more specific properties.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available