Can you help me Please?
In As toxicity how many ATPs are produced from one molecule of Glucose?
In As toxicity how many ATPs are produced from one molecule of Glucose?
Arsenate Poisoning and ATP production
- Thread starter DrTomGr
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Either UWorld or Kaplan had a question on this.
You've just gotta know that, in glycolysis, normally we have G3P --> 1,3-BPG --> 3PG. The second step creates ATP. Per molecule of glucose, this = 2ATP for this latter step.
Arsenic/arsenate causes G3P --> 3PG, therefore bypassing the 1,3-BPG production. Because 1,3-BPG is not created, ATP cannot be produced from the conversion to 3PG, so zero ATP are created here. Since glycolysis is normally a production of 2 net ATP, when arsenic poisoning occurs, zero net ATP are produced from glycolysis.
THANK YOU!
This is what i was thinking too, but i was a little confused from a question in BRS (i think it was totally wrong). I assume that because As also inhibits PDH & α-KG DH there is an inhibition in TCA circle. So NO ATP even in aerobic metabolism.
Am I right?
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I wouldn't go so far as to say the latter. In glycolysis, one of the steps is completely bypassed, so no ATP is produced, but in the TCA cycle, the enzymes you've mentioned are inhibited (based on arsenic's inhibition of lipoic acid), such that Vmax would decrease, but would not = 0. So I'd think ATP is still produced in the TCA cycle.
