Joel Kaar

Joel KaarAssistant Professor
JSCBB C226
(303) 492-6031
joel.kaar@colorado.edu
Curriculum Vitae

Education

Ph.D. (Chemical Engineering), University of Pittsburgh, 2007
B.S. (Chemical Engineering), University of Pittsburgh, 2001

Awards

  • Medical Research Council Career Development Fellowship, 2008 – 2010
  • Tissue Engineering and Regenerative Medicine International Society Poster Session “Second Place Award for Best Paper”, 2007
  • American Institute of Chemical Engineers Annual Student Poster Competition “First Place Award for Best Paper”, 2001
  • National Science Foundation Research for Undergraduates Fellowship, University of Pittsburgh, Summer 2001


Selected Publications

  • Kaar JL, Basse N, Joerger AC, Stephens E, Rutherford TJ, Fersht AR. Stabilization of mutant p53 vial alkylation of cysteines and effects on DNA binding. Protein Science (Accepted).
  • Kaar JL. Lipase activation and stabilization in room temperature ionic liquids. Methods Mol Biol 2009 (Accepted).
  • Basse N1, Kaar JL1, Joerger AC, Rutherford TJ, Fersht AR. Towards the rational design of p53 stabilizing drugs: probing the surface of the oncogenic Y220C mutant. Chem Biol 2010;17(1):46-56.
    (1)Authors contributed equally
  • Kaar JL, Li Y, Blair HC, Asche G, Koepsel RR, Huard J, Russell AJ. Matrix metalloproteinase-1 treatment of muscle fibrosis. Acta Biomater 2008;4(5):1411-1420.
  • Depp V, Kaar JL, Russell AJ, Lele BS. Enzyme sheathing enables nanoscale solubilization of biocatalyst and dramatically increases activity in organic solvent. Biomacromolecules 2008;9(4):1348-1351.
  • Kaar JL1, Oh H1, Russell AJ, Federspiel WJ. Towards improved artificial lungs through biocatalysis. Biomaterials 2007;28(20):3131-3139. 1Authors contributed equally
  • Bedair H, Liu TT, Kaar JL, Shown B, Russell AJ, Huard J, Li Y. Matrix metalloproteinase (MMP) therapy improves muscle healing. J Appl Physiol 2007;102(6):2338-2345.
  • Xu H, Kaar JL, Russell AJ, Wagner WR. Characterizing the modification of surface proteins with poly(ethylene glycol) to interrupt platelet adhesion. Biomaterials 2006;27(16):3125-3135.
  • Russell AJ, Kaar JL, Berberich JA. Using biotechnology to detect and counteract chemical weapons. The Bridge (a publication of the Nation Academy of Engineering) 2003;33(4):19-24.
  • Berberich JA, Kaar JL, Russell AJ. Use of salt hydrate pairs to control water activity for enzyme catalysis in ionic liquids. Biotechnol Prog 2003;19(3):1029-1032.
  • Kaar JL, Jesionowski AM, Berberich JA, Moulton R, Russell AJ. Impact of ionic liquid physical properties on lipase activity and stability. J Am Chem Soc 2003;125(14):4125-4131.
  • Russell AJ, Erbeldinger M, DeFrank JJ, Kaar J, Drevon G. Catalytic buffers enable positive-response inhibition-based sensing of nerve agents. Biotechnol Bioeng 2002;77(3):352-357.


Research Interests

Our research is broadly focused on the symbiotic interfacing of proteins, namely enzymes, and materials. Specifically, we are interested in developing novel functional materials and approaches to material synthesis that exploit the exquisite properties (specificity, catalytic activity, self-assembly) and natural diversity of proteins. Within the context of this focus, we are studying how the microenvironment of proteins at material interfaces impacts protein function. An understanding of the link between protein structure, activity, and molecular environment is a requisite for designing rational strategies for incorporating proteins into materials and, more broadly, using proteins in new ways. The work in our group has considerable implications towards the use of enzymes for green chemistries, which reduce pollution and energy costs and increase safety, the design of tissue scaffolds with improved regenerative properties, the creation of biopolymers that sense and destroy toxic agents, and the development of renewable energy technologies.

The study of proteins in non-natural solvent environments
As solvents for the enzymatic synthesis of functional monomers and polymers, ionic liquids (ILs; salts that are liquid at ambient temperatures) have highly attractive properties. Notable properties of ILs include thermal stability and nonexistent vapor pressure, which render ILs an environmentally attractive solution to polluting organic solvents. Additionally, ILs can be tailored to dissolve virtually any materials by interchanging the cation and anion and thus designed for a specific reaction system. However, despite intense interest in the use of ILs for anhydrous biocatalysis, very little is known about how ILs interact with enzymes. This has greatly hindered the application of ILs in enzymatic processes, which has, to date, met with only modest success. The limited success calls to question the broader utility of ILs with enzymes unless the mechanism of enzyme deactivation in ILs can be understood and reversed.
The aim of this research area is to address the fundamental question of how ILs impact enzyme structure and dynamics at the molecular level. We are specifically interested in elucidating the propensity and manner in which cations and anions in families of ILs bind to sites on the surface of and destabilize enzymes, the impact of ILs on the folding states and active site plasticity of enzymes as a function of IL properties, and strategies to mediate enzyme-solvent interactions that inactivate enzymes in ILs. Ultimately, this work will enable the framework to fully realize the scope of feasible biocatalytic reactions in ILs.

Rational biomaterial synthesis
Combining the power of biology and the sophistication of polymers presents the potential to engender innovative materials. Protein-containing polymers can be prepared by reacting a prepolymer with a protein, resulting in multipoint covalent immobilization of the protein within the polymer network. To create biomaterials with enhanced functional properties, we are designing rational synthetic schemes that preserve the activity and control the supramolecular assembly of proteins in materials and which are scalable. In developing fundamental design principles, we are interested in resolving how the conformation of proteins and timescale of protein dynamics is perturbed upon incorporation into materials, the forces (chemical and structural) that destabilize proteins at material interfaces, and ubiquitous structural elements in proteins whose modification does not compromise protein function. Moreover, we are devising strategies to guide the spatial immobilization of proteins within materials, which enable complete control over material properties.