Just wondering exactly the disparity between the two. Cuz i am getting murdered on UsmleWorld biochem like 60% i think and am wondering if i have to know obscure details about TCA cycle...for example I had no idea that methylmalonyl CoA was isomerized in a B12 dependent reaction to Succinyl CoA ....or maybe im an idiot i dont know. Possibly both.

input?

UW is very detailed but i think if we spent some time on it it can help us score in obscure questions

1-Fa will cover the easy things.
2-UW will cover the hard things and will make you think.
When you take the test, the questions that are under that level of difficulty you will be able to answer them. Also just by using the knowledge you gain from those questions you will be able to answer other Bioch. questions on the test.

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hey,
the reason thats important is more to do with B12 deficiency , its in FA biochem vitamin section pg 80 (2007 edition), its pretty highyield...the thing i find about UW, they test these HY facts but in the most absurd way,

but succinyl CoA can enter the heme synthesis pathway or TCA cycle
and the build up of methylmalonyl CoA and proplonyl CoA are supposed to cause demylination, which is why u have neurologic sx's with B12 def Vs. B6

but i totaly agree with you on UW sometimes when im going through q's i have this rxn ->

(A)propionyl CoA carboyxylase (biotin cofactor)

(B)methylmanlonyl mutase(b12)


propionyl-CoA---------------->methylmalonyl CoA------>succinyl CoA

(so i cant figure out how to put the enzymes over the arrows, but
(A) is the enzyme responsible for propionyl-CoA to methylmalonyl CoA
(B) is responsible for methylmalonyl CoA to succinyl CoA)

hope that makes sense , golijan does a good job too in his vitamin section

Thanks! That's a good way to think of it.

yes it is bravo

I think you meant neurological sx with B12 and not Folate. B6 deficiency and overdose cause peripheral neuropathies (i.e. isoniazid therapy).