Current efforts are focused on industrially important biotransformation problems such as those found in hydrogenation, hydroxylation and aromatic amino acid metabolic pathways. The methods used include site-directed mutagenesis, calorimetry, chromatography, circular dichroism, ellipsometry, spectroelectrochemistry, and X-ray diffraction. Biocatalysis studies usually involve a coordinated application of several methodologies such as spectroscopy, kinetics, thermodynamics, and structure determinations. We have recently applied some or all of these tools to alanine dehydrogenase, putidaredoxin, and desaturase to gain structural, thermodynamic, and mechanistic information, and are currently focusing on the pharmaceutically important nitrilase enzymes.

• Thermodynamic data for nitrilase catalyzed enzyme reactions. The importance of nitrilase enzymes has led recently to the commercial development of a library consisting of over 200 new forms of this enzyme. We selected several representative (model) nitrilase-catalyzed reactions for a thermodynamic investigation, which was accomplished by using HPLC and calorimetry combined with equilibrium modeling calculations. The thermodynamic results obtained in this study provide quantitative data that can be used for the bioprocess engineering (design of bioreactors and conditions of reaction) of these enzyme-catalyzed reactions. The results are the first to be reported in the literature.
• Chorismate Pathway Enzymes: Structural Studies. We have studied how aromatic hydrocarbons are produced enzymatically in bacteria. Aromatic hydrocarbons are difficult to produce synthetically. However the elucidation of natural biochemical pathways makes it easier to alter and utilize these pathways to make these and similar chemicals. In particular, the phenazines, which are produced by a branch of the chorismate pathway in some bacteria, are difficult to synthesize but are important potential drugs.
• The Thermodynamics of Enzyme-Catalyzed Reactions Database ( http://xpdb.nist.gov/enzyme_thermodynamics/ ) has been converted to a fully relational database by using the Oracle database management software. It can now be searched by users in an extremely wide variety of ways.

• Y.B. Tewari and R.N. Goldberg, “ Thermodynamics of the hydrolysis reactions of nitriles”, J. Chem. Thermodynamics, in press.
• J. F. Parsons, F. Song, L. Parsons, K. Calabrese, E. Eisenstein, J. E Ladner, “ Structure and Function of the Phenazine Biosynthesis Protein PhzF from Pseudomonas fluorescens” . Biochemistry 2004, 43, 2-79 .
• J.F. Parsons, K. Calabrese, E. Eisenstein, J.E. Ladner, “ Structure of the Phenazine Biosynthesis Enzyme PhzG” Acta Cryst. D: Biol. Cryst. 2004, 60 2110-2113.
• NIST Standard Reference Database 74: Thermodynamics of Enzyme-Catalyzed Reactions. http://xpdb.nist.gov/enzyme_thermodynamics/
• Y. B. Tewari, M. M. Schantz, K. W. Phinney, J. D. Rozzell, “A thermodynamic study of the ketoreductase-catalyzed reduction of 2-alkanones in non-aqueous solvents” J. Chem. Thermodynamics 2005, 37, 89-96.
• D. T. Gallagher, H. G. Monbouquette, I. Schröder, H. Robinson, M. J. Holden, N. N. Smith, “Structure of Alanine Dehydrogenase from Archaeoglobus : Active Site Analysis and Relation to Bacterial Cyclodeaminases and Mammalian mu Crystallin,” J. Mol. Biol. 2004, 342, 119-130.