P450 biocatalysis in two-phase emulsions using biomimetic NADH

CATL 49

Jessica D Ryan, jessryan@berkeley.edu1, Richard H. Fish2, and Douglas S Clark, clark@cchem.berkeley.edu1. (1) Department of Chemical Engineering, University of California at Berkeley, 201 Gilman Hall, Berkeley, CA 94720, (2) Lawrence Berkeley National Laboratory, University of California, Berkeley, CA 94720
Cytochrome P450 biocatalysis is an attractive potential alternative to traditional chemical synthesis for achieving asymmetric hydroxylations, but many factors limit the large-scale integration of P450s into synthetic schemes. In particular, the expense of the required NAD(P)H cofactor and the poor water solubility of many potential substrates are major obstacles for the use of isolated P450 preparations. We have shown that two-phase emulsions containing small amounts (<5 wt%) of bis(2-ethylhexyl) sulfosuccinate sodium salt (AOT) enable faster reaction rates and higher overall product yields for P450cam mediated hydroxylations. We have also shown that P450cam can accept reducing equivalents from a biomimetic analog of NADH, 1,4-dihydrobenzylnicitinamide, which can be regenerated from the oxidized form using an organometallic rhodium complex ([Cp*Rh(Bpy)H]+) as an alternative to using a second enzyme. Protein engineering strategies for improving the oxidation kinetics of the analog will also be presented.
 

Strategies in Enzymatic Oxidation Catalysis
1:30 PM-4:55 PM, Wednesday, August 22, 2007 BCEC -- 261, Oral

Catalysis & Surface Science Secretariat

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007