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Old 02-25-2011
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Biochemistry Thiamine Deficiency; which enzyme to be tested?

which of following enzyme function will you test to look for thiamine deficiency??

A : pyruvate hehydrogenase
B : alpha-ketoglutarate dehydrogenase
C : acetyl carboxylase
D : transketolase
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Old 02-25-2011
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D. Transketolase.

Because, it requires only thiamine, while other dehydrogenases require thiamine+other factors as well.
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Old 02-25-2011
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Quote:
Originally Posted by drahmednawaz View Post
D. Transketolase - because it requires only thiamine, while other dehydrogenases require thiamine + other factors as well.
Definitely!

Now if the question were:
A patient presents with suspected thiamine deficiency; what is the most appropriate diagnostic measure?
  1. administer thiamine
  2. assay erythrocyte transketolase activity
  3. measure serum alphaketoglutarate
  4. measure serum thiamine
  5. measure urinary methylglyoxal
  6. perform thiamine loading test

the best answer would be A. administer thiamine...
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Old 02-25-2011
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Answer is D

Reason (as already told by drahmednawaz)

A&B require cofactors like : thiamine pyrophosphate, lipoic acid, coenzyme A, flavin adenine dinucleotide (FAD), and nicotinamide adenine dinucleotide (NAD).

C : does not require thiamine

D :requires only thiamine
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