Kenneth A. Johnson

Email: kajohnson@mail.utexas.edu

Kenneth A. Johnson received his B.S. in Chemistry at the University of Iowa in 1971 and his Ph.D. in Molecular Biology from the University of Wisconsin in 1975 for work with Dr. Gary Borisy on the dynamics of microtubule assembly. He then pursued postdoctoral training with Dr. Edwin Taylor at the University of Chicago where he first learned transient kinetic methods in studies on the actomyosin ATPase. Dr. Johnson's first academic appointment was in the Department of Biochemistry and Molecular Biology at The Pennsylvania State University where he rapidly rose to the rank of Paul Berg Professor of Biochemistry. In 1998, he joined the faculty of the Department of Chemistry and Biochemistry and the Institute for Cellular and Molecular Biology at the University of Texas at Austin as the Roger Williams Professor of Biochemistry.

Dr. Johnson's current research focuses on the kinetic basis for DNA polymerase fidelity including structure/function studies on HIV reverse transcriptase and the human mitochondrial DNA polymerase aiming to understand molecular basis for the effectiveness and toxicity of nucleoside analogs used to treat HIV infections. Recent results have established the important role played by nucleotide-induced structural changes in governing the specificity of DNA polymerases. Future studies focus on the dynamics of these conformational changes as predicted using molecular dynamics simulations and as measured by stopped-flow fluorescence methods. He is also continuing studies on the mechanism of force production by the microtubule-dependent motor, kinesin, using single molecule and transient kinetic methods. Finally, Johnson is also working to develop better methods for fitting kinetic data globally based upon numerical integration of rate equations.

References:

Tsai, Y. C., and Johnson, K. A. (2006) A new paradigm for DNA polymerase specificity, Biochemistry. 45, 9675-9687.

Johnson, K. A. (2008) Role of induced fit in enzyme specificity: a molecular forward/reverse switch, J Biol Chem 283, 26297-26301.

Johnson, K. A., Simpson, Z. B., and Blom, T. (2009) Global Kinetic Explorer: A new computer program for dynamic simulation and fitting of kinetic data, Anal Biochem 387, 20-29.

 

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