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Old 06-24-2012
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Biochemistry Carcinogen Metabolic Pathway!

In an experiment, the effects of xenobiotic activation of the compound benzo[a]pyrene, a chemical carcinogen present in cigarette smoke, are studied in various tissues. Investigators determine that formation of a secondary metabolite, which binds covalently to DNA, increases the frequency of lung cancers. Which of the following is the most likely metabolic pathway for generation of this xenobiotic?

a) biomethylation
b) cyt. P-450
c) flavin-containing monooxygenase
d) glucuronidation
e) glutathione
f) peroxidase-dependent cooxidation

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  #2  
Old 06-24-2012
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Hi I think the answer is C) Flavin-containing mono oxygenase because most carcinogens are metabolized by a mono oxygenase.
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Old 06-24-2012
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i would go for c) flavin-containing monooxygenase
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Old 06-24-2012
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I'm putting my money on b)
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Old 06-24-2012
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Default Benzopyrene: scary

Just wikied about Benzopyrene and came to know that its a polycyclic aromatic hydrocarbon which can be present in forest fires, volcano eruption, cigarette smoke and guess what? It also get deposited on food which we BBQ
and its a potential pollutant and carcinogenic. Oh got now what will happen to my next week BBQ party if this new gets viral among my friends
Sorry for a small distraction. Keep on thinking about the answer anyways.
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Old 06-24-2012
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CytP450 Bbbbb
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Old 06-24-2012
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its B.....CYTO P450 is the king when it comes to metabolizing outside stuff....
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Old 06-26-2012
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Default correct answer :)

Correct answer is B) Cytochrome P-450

The cytochrome P-450-dependent monooxygenase, or mixed function oxidase, system is found in smooth endoplasmic reticulum and normally functions to detoxify endogenous hormones. However, it can also serve to activate xenobiotics to carcinogens.

Flavin-containing monooxygenase found in endoplasmic reticulum can oxidase nicotin.

Glucuronidation can convert naphtylamine to a carcinogen that causes urinary tract cancers.

The proxidase-dependent cooxidation pathway can metabolize 2-naphthylamine to a carcinogen that causes urinary tract cancers.
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