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mnQ/A's for the final exam:

-Foye’s:”The CYP450 monooxygenases resulting from this supergene family have been subdivided into families with greater than 40% amino acid homology and subfamilies with greater than 55% homology.”

“Members in the same family (i.e. CYP1A1, CYO1A2, CYP1B1, CYP1B2, CYP1C1, CYP1C2, etc.) share more than 40% homology in protein sequence.”

“Members in the same subfamily (i.e. CYP1A1, CYP1A2, and CYP1A3) share more than 55% homology in protein sequence.”

90% is not a cut-off line.

-Conjugation reactions:

Substrate (drugs; xenobiotics) + co-factor --- product (substrate-conjugate complex)+ cofactor without the conjugate part (e.g., SO4 in sulfation)

Glycine and glutamine conjugations are slighly different:

Substrate-cofactor (CoA) + glycine or glutamine -- Product (substrate with glycine or glutamine conjugate) + Coenzynme A. -P450 catalytic cycle For the catalytic reaction cycle on page 7, handout 6, know how many H2O formed and how many electrons and O2 are required for each cycle. You don’t have to know where the O2 comes from. -Other oxdative enzymes Regarding other oxdative enzymes, such as xenthine oxdatase, you don’t have to memorize the whole pathway but just the name of the enzyme, the nature of the reactions (oxidation). The main part of oxidation reaction lecture is P450. The other enzymes including xanthine oxidase are examples of addtional oxidation reactions and enzymes.

-Phase II reactions. Following the study guide. The reactions are the sampels to tell you the mechanisms of phase II reactions. For the exam, focus on the names of phase II enzymes and cofactors (The synthetases for cofactors are not required) and the nature of phase II reactions. Know the names of differnet conjugates.

-"pi" of 2/3 benzene Understand how the "pi" of the 2/3 benzene was calcualted by Hansch from differnet compounds listed in the handout.

-The equations and charts will be provided in the exam.

jonathan.sheng@mcphs.edu

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