Extensive site-directed mutagenesis reveals interconnected functional units in the alkaline phosphatase active site
Abstract
Enzymes enable life by accelerating reaction rates to biological timescales. Conventional studies have focused on identifying the residues that have a direct involvement in an enzymatic reaction, but these so-called ‘catalytic residues’ are embedded in extensive interaction networks. Although fundamental to our understanding of enzyme function, evolution, and engineering, the properties of these networks have yet to be quantitatively and systematically explored. We dissected an interaction network of five residues in the active site of Escherichia coli alkaline phosphatase. Analysis of the complex catalytic interdependence of specific residues identified three energetically independent but structurally interconnected functional units with distinct modes of cooperativity. From an evolutionary perspective, this network is orders of magnitude more probable to arise than a fully cooperative network. From a functional perspective, new catalytic insights emerge. Further, such comprehensive energetic characterization will be necessary to benchmark the algorithms required to rationally engineer highly efficient enzymes.
- Authors:
-
- Department of Biochemistry, Beckman Center, Stanford University, Stanford, United States
- Molecular and Cellular Biochemistry Department, Indiana University Bloomington, Bloomington, United States
- Publication Date:
- Research Org.:
- SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States). Stanford Synchrotron Radiation Lightsource (SSRL)
- Sponsoring Org.:
- USDOE Office of Science (SC), Basic Energy Sciences (BES); USDOE Office of Science (SC), Biological and Environmental Research (BER); National Institutes of Health (NIH); National Center for Research Resources (NCRR); National Institute of General Medical Sciences (NIGMS); National Science Foundation (NSF)
- OSTI Identifier:
- 1182427
- Alternate Identifier(s):
- OSTI ID: 1198402; OSTI ID: 1628834
- Grant/Contract Number:
- Office of Biological and Environmental Research; AC02-76SF00515; GM64798; GM049243
- Resource Type:
- Published Article
- Journal Name:
- eLife
- Additional Journal Information:
- Journal Name: eLife Journal Volume: 4; Journal ID: ISSN 2050-084X
- Publisher:
- eLife Sciences Publications, Ltd.
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 59 BASIC BIOLOGICAL SCIENCES; Life Sciences & Biomedicine - Other Topics
Citation Formats
Sunden, Fanny, Peck, Ariana, Salzman, Julia, Ressl, Susanne, and Herschlag, Daniel. Extensive site-directed mutagenesis reveals interconnected functional units in the alkaline phosphatase active site. United States: N. p., 2015.
Web. doi:10.7554/eLife.06181.
Sunden, Fanny, Peck, Ariana, Salzman, Julia, Ressl, Susanne, & Herschlag, Daniel. Extensive site-directed mutagenesis reveals interconnected functional units in the alkaline phosphatase active site. United States. https://doi.org/10.7554/eLife.06181
Sunden, Fanny, Peck, Ariana, Salzman, Julia, Ressl, Susanne, and Herschlag, Daniel. Wed .
"Extensive site-directed mutagenesis reveals interconnected functional units in the alkaline phosphatase active site". United States. https://doi.org/10.7554/eLife.06181.
@article{osti_1182427,
title = {Extensive site-directed mutagenesis reveals interconnected functional units in the alkaline phosphatase active site},
author = {Sunden, Fanny and Peck, Ariana and Salzman, Julia and Ressl, Susanne and Herschlag, Daniel},
abstractNote = {Enzymes enable life by accelerating reaction rates to biological timescales. Conventional studies have focused on identifying the residues that have a direct involvement in an enzymatic reaction, but these so-called ‘catalytic residues’ are embedded in extensive interaction networks. Although fundamental to our understanding of enzyme function, evolution, and engineering, the properties of these networks have yet to be quantitatively and systematically explored. We dissected an interaction network of five residues in the active site of Escherichia coli alkaline phosphatase. Analysis of the complex catalytic interdependence of specific residues identified three energetically independent but structurally interconnected functional units with distinct modes of cooperativity. From an evolutionary perspective, this network is orders of magnitude more probable to arise than a fully cooperative network. From a functional perspective, new catalytic insights emerge. Further, such comprehensive energetic characterization will be necessary to benchmark the algorithms required to rationally engineer highly efficient enzymes.},
doi = {10.7554/eLife.06181},
journal = {eLife},
number = ,
volume = 4,
place = {United States},
year = {Wed Apr 22 00:00:00 EDT 2015},
month = {Wed Apr 22 00:00:00 EDT 2015}
}
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