Codexis offers a comprehensive line of Human Cytochrome Biocatalysts, the first fully formulated human P450 enzyme system for use in screening and synthesizing drug metabolites. The company also offers MicroCyps, the first commercial source of modified bacterial cytochrome P450 enzymes for producing drug metabolites and generating new lead compounds. These enzymes can also be used to generate novel compounds that are difficult to manufacture chemically and serve as useful starting points for drug discovery.

Major applications of metabolite production include screening to identify the human cytochrome most active in metabolizing a given drug, and the ability to produce sufficient quantities of drug metabolites to enable toxicity studies.