1978 B.S., Northwestern University
1982 D.D.S., University of Illinois
1993 Ph.D., California Institute of Technology

Our group is focusing on lessons from Nature, i.e., how does Nature create three-dimensional inorganic/organic based materials like sea shells, invertebrate exoskeletons, and vertebrate bone. As we understand it, the process involves proteins that assemble into supramolecular structure that interact with inorganic surfaces (minerals). The resulting biocomposite structure is usually fracture-resistant and can perform other functions such as surface catalysis and transmission of light.

Our ultimate goal is to determine the molecular properties that allow these protein-based matrices to assemble and participate in the formation of naturally-occuring organic/inorganic materials. Ultimately, this requires knowledge of polypeptide three-dimensional structure, and how this impacts the self-assembly process and the physical properties of the biocomposite. This information can then be applied in material engineering to create new synthetic materials. The experimental aspects of our research include the use of NMR and EPR spectroscopy. NMR spectroscopy assists in the determination of protein sequences that are specific to bio-based matrices. NMR experiments can also provide information on polypeptide-interfacial interactions and the dynamics of polypeptide conformation and assembly. EPR spectroscopy, which has an inherently higher sensitivity, can determine protein - metal ion complexation, and, via the use of nitroxyl spin labels, can be used to probe protein conformation and dynamics.

Another experimental tool that we use is MALDI/TOF spectrometry. This method can be used to define ligand binding sites on polypeptides and assess polypeptide conformational change that occurs during metal ion binding and protein - protein self-assembly. Bio-based material architecture can also be explored using molecular simulations and computational methods. Our group is involved in the development of novel algorithms that can map self-assembly processes, protein - interfacial interactions, and bio-based nucleation processes and can be used to predict protein structure. Our theoretical studies have included macroscopic modeling of protein-based elasticity, microscopic modeling of protein - interfacial docking and recognition, and molecular dynamics of self-assembly and nucleation, using a combination of ab initio and mechanistic methods.

Office of Army Research
Department of Defense Nanotechnology Program (DURINT)

Xu, G, Evans, JS (1999) Model peptide studies of sequence repeats derived from the Intracrystalline biomineralization protein, SM50. I. GVGGR and GMGGQ repeats Biopolymers 49: 303-312; Errata. Biopolymers 50: 345.

Zhang, B, Xu, G, Evans, JS (1999) A kinetic molecular model of the reversible unfolding and refolding of titin under force extension. Biophysical J. 77: 1306-1315.

Xu, G., Zhang, B., and Evans, JS (1999) PFG-filtered TOCSY experiments for the determination of long-range heteronuclear and homonuclear coupling constants, and, estimation of J-coupling 'crosstalk' artifacts in 2-D filtered 'E. COSY-Style' spectra. Journal of Magnetic Resonance, 138: 127-134.

Dai, Y and Evans, JS (2000) An energy-based mapping method for identifying the in-plane orientations of polypeptides and other macromolecules at crystalline interfaces. J. Chemical Physics 112: 5144-5157; errata 113: 2509.

Zhang, B, Xu, G., and Evans, J.S., (2000) Model peptide studies of sequence repeats derived from the Intracrystalline biomineralization protein, SM50. II. Pro, Asn-Rich Tandem Repeats. Biopolymers 54: 464-475.

Zhang, B., and Evans, J.S. (2001) Modeling AFM-induced PEVK extension and the reversible unfolding of Ig/FNIII domains in single and multiple titin molecules. Biophysical J. 80: 597-605.

Dai, Y., and Evans, J.S. (2001) Examining macromolecular orientation and interaction at crystal growth steps using an energy-based dual Miller plane mapping algorithm. Langmuir 2001, 17, 4134-4138.

Dai, Y, Evans, JS, Molecular dynamics simulations of template - assisted nucleation: Alcohol monolayers at the air-water interface and ice formation. J. Phys. Chem. B 2001, 105, 10831-10837.

Zhang, B, Wustman, BA, Morse, DE, Evans, JS, Model peptide studies of sequence regions in the elastomeric biomineralization protein, Lustrin A. I. The C-domain consensus -PG-, NVNCT- motif. Biopolymers, 2002, 63, 358-369.

Wustman, BA, Santos, R, Zhang, B, Evans, JS, Identificaion of a ôglycine loopö-like coiled structure in the 34-AA Pro, Gly, Met repeat domain of the biomineral-associated protein, PM27. Biopolymers, 2002, 65, 362-372.

Wustman, BA, Morse, DE, Evans, JS, Structural analyses of polyelectrolyte sequence domains within the adhesive elastomeric biomineralization protein Lustrin A. Langmuir 2002, 18, 9901-9906.

Evans, JS, ôApplesö and ôOrangesö: Comparing the structural aspects of biomineral- and ice-interaction proteins. Current. Opinion in Colloid and Interfacial Science, 2003, in press.

Michenfelder, M, Fu, G, Lawrence, C, Weaver, JC, Wustman, BA, Taranto, L, Evans, JS, Morse, DE, Characterization of two molluscan crystal-modulating biomineralization proteins and identification of putative mineral binding domains. Biopolymers, 2003, in press.