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CypExpress 3A4 Cytochrome P450 human

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CP33, CP34, CYP3A, CYP3A3, CYP3A4, CYPIIIA3, CYPIIIA4, HLP, NF-25, P450 3A4, P450C3, P450PCN1
EC Number:

biological source



expressed in Pichia pastoris


dry powder

UniProt accession no.


cell analysis

shipped in

dry ice

storage temp.


Gene Information

human ... CYP3A4(1576)

Biochem/physiol Actions

Cytochrome P450 enzymes are heme containing monooxygenases which are found primarily in the mammalian liver. They catalyze the oxidative metabolism of xenobiotics. This metabolism is the initial step in the biotransformation and elimination of a wide variety of drugs and environmental pollutants from the body. Ketoconazole, itraconazole, azamulin, troleandomycin and verapamil are inhibitors, whereas rifampin is an inducer of the enzyme. The isozyme CYP3A4 is a major pathway for the invivo conversion of testosterone to 6β-Hydroxytestosterone via hydroxylation.
Cytochrome P450 is a heterogeneous family of isozymes whose primary function is to oxidize small molecules, both as a function of intermediary metabolism (e.g., fatty acids) and to detoxify exogenous compounds like xenobiotics, pollutants and drug molecules. Cytochrome P450 3A4 (CYP3A4) is one of the isoforms of cytochrome P450 (P450s). CYP3A4 oxidizes more than 90% of marketed drugs through various metabolic processes.

Features and Benefits

CypExpress 3A4 is a permeabilized and stabilized dried yeast powder preparation containing full length, unmodified, human CYP 3A4 and recombinant human NADPH oxidoreductase. Using proprietary processes, CypExpress are expressed in Pichia yeast. Following optimal expression, the cells are inactivated, permeabilized and dried to a fine powder. CypExpress retains the cellular mechanisms to provide the P450 enzymes with the energy and cofactors to continue to function for long experiments, and can generate larger amounts of metabolite than mammalian microsomes or other genetically engineered expression systems. It is designed for rapid screening of drug metabolites and for scaling up metabolite generation.

Unit Definition

A reaction mixture containing 500 μM testosterone and 100 mg/mL of CypExpress 3A4 will produce 121.9 μM 6b-hydroxytestosterone in 3 hours at 30°C under the conditions described.

Physical form

Light yellow, very fine powder


Per Protocol/Variable

Legal Information

6538 is a trademark of American Type Culture Collection
CypExpress is a trademark of Oxford Biomedical Research

Storage Class

11 - Combustible Solids




Not applicable


Not applicable

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