Matrix-Based Activity Pattern Classification as a Novel Method for the Characterization of Enzyme Inhibitors Derived from High-Throughput Screening.
One of the central questions in the characterization of enzyme inhibitors is determining the mode of inhibition (MOI). Classically, this is done with a number of low-throughput methods in which inhibition models are fitted to the data. The ability to rapidly characterize the MOI for inhibitors arising from high-throughput screening in which hundreds to thousands of primary inhibitors may need to be characterized would greatly help in lead selection efforts. Here we describe a novel method for determining the MOI of a compound without the need for curve fitting of the enzyme inhibition data. We provide experimental data to demonstrate the utility of this new high-throughput MOI classification method based on nonparametric analysis of the activity derived from a small matrix of substrate and inhibitor concentrations (e.g., from a 4S× 4Imatrix). Lists of inhibitors from four different enzyme assays are studied, and the results are compared with the previously described IC50-shift method for MOI classification. The MOI results from this method are in good agreement with the known MOI and compare favorably with those from the IC50-shift method. In addition, we discuss some advantages and limitations of the method and provide recommendations for utilization of this MOI classification method.
1 Novartis Institutes for Biomedical Research, Center for Proteomic Chemistry, Cambridge, MA, USA.
Douglas S
DS
Auld
1 Novartis Institutes for Biomedical Research, Center for Proteomic Chemistry, Cambridge, MA, USA.
Marta
M
Jimenez
1 Novartis Institutes for Biomedical Research, Center for Proteomic Chemistry, Cambridge, MA, USA.
Kimberley
K
Yue
1 Novartis Institutes for Biomedical Research, Center for Proteomic Chemistry, Cambridge, MA, USA.
Scott
S
Busby
1 Novartis Institutes for Biomedical Research, Center for Proteomic Chemistry, Cambridge, MA, USA.|2 National Center for Advancing Translational Sciences, Bethesda, MD, USA.
Yu-Chi
YC
Chen
1 Novartis Institutes for Biomedical Research, Center for Proteomic Chemistry, Cambridge, MA, USA.
Scott
S
Bowes
1 Novartis Institutes for Biomedical Research, Center for Proteomic Chemistry, Cambridge, MA, USA.
Greg
G
Wendel
1 Novartis Institutes for Biomedical Research, Center for Proteomic Chemistry, Cambridge, MA, USA.
Thomas
T
Smith
1 Novartis Institutes for Biomedical Research, Center for Proteomic Chemistry, Cambridge, MA, USA.
Ji-Hu
JH
Zhang
D004353:Drug Evaluation, Preclinical / Q000379:methods; D004791:Enzyme Inhibitors / Q000737:chemistry* / Q000145:classification; D004798:Enzymes / Q000737:chemistry*; D057166:High-Throughput Screening Assays / Q000379:methods*; D006801:Humans
D004791:Enzyme Inhibitors; D004798:Enzymes
enzyme assays; enzyme inhibitors; inhibitor classification; mode of inhibition