Cytochrome P450 Questions: Trivia Quiz!

Dimeric proteins, 40 - 50,000 MW; haem group with F2 in 2+ state

Multimeric proteins, 40 - 45,000 MW; protoporphyrin XI haem group

Monomeric proteins 40 - 50,000 MW; protoporhyrin IX haem prosthetic group

Xenobiotic metabolism; steroid, fatty acid and vitamin reduction; steroid synthesis

Xenobiotic metabolism; steroid, fatty acid and vitamin oxidation; steroid biosynthesis

Xenobiotic metabolism; steroid, fatty acid and acetaldehyde oxidation; steroid biosynthesis

DOH + NADPH + O2 --> DH + NADP + H20

DH + NADPH + O2 --> DOH + NADP + H2O

DH + NADP + H2O --> DOH + NADP + 02

Highest levels in liver; lower levels in kidney and lung; some forms e.g. CYP1A1 only extrahepatic

Highest levels in liver; lower levels in kidney and intestine; some forms e.g. CYP3A1 only extrahepatic

Highest levels in liver; lower levels in gut and duodenum; some forms e.g. CYP1A2 only extrahepatic

Areas of strong H-bond forming potential 5 - 7 A from site of metabollism; mainly NSAIDs but also warfarin and paracetamol

Areas of strong H-bond forming potential 5 - 7 A from site of metabolism; mainly CVS agents, also S-warfarin, paracetamol and aspirin

Areas of strong H bond/ion forming potential 5 - 10 A from site of metabolism; mainly NSAIDs, also S-warfarin, tolbutamide and ibuprofen

Basic Nitrogen mainly ionised at physiological pH and a hydrophobic region, oxidation usually 5 - 7 A from basic N; mostly CVS and psychoactive agents e.g. propanolol, debrisoquine, amitriptyline, clozapine

Acidi Nitrogen mainly ionised at physiological pH and a hydrophilic region, oxidation usually 5 - 10 A from acidic Nitrogen; mostly CVS and psychoactive agents e.g. propranolol, desrioquine, amitriptyline, clozapine

Basic Nitrogen mainly ionised at physiological pH and a hydrophobic region, oxidation usually 5 - 7 A from basic N; mostly NSAIDs, also tolbutamide and S-warfarin

Large binding site allowing for considerable structural diversity in substrates, majority of binding involves ionic bonding; rifampicin, penicillin

Large binding site allowing for considerable structural diversity in substrates, majority of binding involving hydrophobic interactions; erythromycin, lidocaine, tamoxifen

Large binding site allowing for considerable structural diversity in substrates, majority of binding involves Hydrogen bonding; erythromycin, rifampicin

CYP2D6, CYPA12, CYP3A4; CYP2C9

CYP2C19, CYP1A2, CYP3A4; CYP2D6

CYP2C9, CYPA12, CYP3A4; CYP2D6

Topography of P450 active site; degree of steric hindrance of access to Fe-O complex; how easily substrate will react

Topography of substrate active site; degree of steric hindrance of access to P450 active site; ease of reaction

Topography of P450 active site; degree of steric hindrance of access to both Fe-O and P450 active site; ease of reaction

Fl atom moved from position 4 to 6 - preferential site of oxidation lost - shorter T1/2

Cl atom moved from position 6 to 4 - preferential site of reduction lost - longer T1/2

Cl atom moved from position 4 to 6 - preferential site of oxidation lost - longer T1/2