Journal of the American Chemical Society
Communication
a
Table 1. Steady-State Kinetic Parameters
AUTHOR INFORMATION
■
Corresponding Author
substrate
parameter
At4CL1
4CL1::STS
p-coumaric acid
kcat
Km
14.9
66.7
22.5
69.9
Author Contributions
§These authors contributed equally.
V/K
kcat
3723
60.3
5365
ATP
CoA
121
Km
39.4
30.9
ACKNOWLEDGMENTS
■
V/K
kcat
25510
53.6
65260
91.1
This work was funded by DOE-DE-SC0001295 and NSF-
MCB-0923779 to O.Y. M.W., a student at Ladue Horton
Watkins High School, was sponsored by the Pfizer-Solutia
Students/Teachers as Research Scientists (STARS) Program.
Portions of this research were carried out at the Argonne
National Laboratory Structural Biology Center at the Advanced
Photon Source, a National User Facility operated by the
University of Chicago for the Department of Energy Office of
Biological and Environmental Research (DE-AC02-
06CH11357).
Km
92.0
58.5
V/K
parameter
9710
VvSTS
25950
4CL1::STS
substrate
p-coumaroyl-CoA
kcat
1.74
18.4
1576
0.58
55.2
175
1.08
4.89
3680
0.48
35.4
226
Km
V/K
kcat
malonyl-CoA
Km
V/K
a
Units for kcat, Km, and V/K are min−1, μM, and M−1 s−1, respectively.
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Mean values (n = 3) are shown; the errors are less than 10%.
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S
* Supporting Information
Details of experimental procedures; X-ray data collection and
refinement statistics (Table S1); purification of At4CL1,
VvSTS, and 4CL::STS (Figure S1); representative electron
density (Figure S2); comparison of 4CL structures (Figure S3);
and identification of p-coumaroyl-CoA (Figure S4). This
material is available free of charge via the Internet at http://
20686
dx.doi.org/10.1021/ja2085993 | J. Am. Chem.Soc. 2011, 133, 20684−20687