2.11-1Carbon&AASyn Flashcards
What two types of catabolism are TetraHydroFolate and SAM especially important in?
Amino Acid and Nucleotide catabolism
TetraHydroFolate & SAM: Which one is involved in oxidation states? Reduction States?
TetraHydroFolate=oxidation steps, SAM=Reduced
TetraHydroFolate & SAM: Which one is involved in nucleotide syn? AA metabolism?
Nucleotide Syn=Folic Acid; AA metabolism=SAM
What is the most oxidized form of Carbon? Which vitamin is it transferred by?
CO2, Biotin
What is the vitamin precursor for TetraHydroFolate?
Folate
What are the three components to folic acid?
Pteridine, PABA, & Glutamate
What is the enzyme that converts our dietary folic acid TO TetraHydroFolate??
DiHydroFolate Reducase (DHR) (It works twice: 1st time REDUCES by adding 2Hs. 2nd time REDUCES by adding 2 more Hs)
Which famous molecule is giving hydrogens in the BUILDING of TetraHydroFolate? :)
NADPH
What is a structural analogue to DiHydroFolate and is there for an inhibitor of DiHydrofolateReducase (DHR)?
METH-O-TREX-ANE, helps with cancer therapy. DHR is a major target to stop very active cells
What is the most common vitamin deficiency in the world? Where is it typically manifested first?
Lack of Folic Acid in diet, blood cells turn over rapidly so megaloblastic anemia is typically the first occurrence
What are the three SPECIFIC metabolisms that require folate?
Purine, thymine, and amino acid metabolism
Which two Nitrogens on TetraHydroFolate carry the methyl groups?
N5 and N10
Is TetraHydroFolate Interconvertable?
YES!
If both THF and SAM can carry a methyl group which one transfers it more efficiently? Why?
SAM, the Sulfur group
What are the two building blocks of SAM? What is the enzyme that makes the magic happen?
ATP + Methionine—->SAM Enzyme: Methionine Adenosyl Transferase
How does SAM even get its CH3? What donates the CH3 and what is the molecule that picks it up to form Methionine?
THF donates the CH3 to HomoCystine to make Methionine
Starting with SAM what are the 5 BASIC steps to the Methyl Cycle?
- SAM gives off its CH3 2. Becomes S-AdenosylHomocystine 3. Add Water to make HomoCystine 4. Add methyl to make Methionine 5. Add ATP to make SAM!
What do RNA->Methylated RNA, DNA->Methylated DNA, and NorEpi->Epi all have in common??
They are all methylated by SAM!
What is the RATE LIMITING STEP to the Methyl cycle? Hint : it has to do with Adding the methyl to the cycle..
MTHFR (Methylene TetraHydroFolate Reductase
What is the methyl trap?
If MTHFR is irreversible, if HomoCystine is not taking methyls MTHFR will just keep adding them on to THF
What three B vitamins have a direct effect on HomoCystine Levels?
Low B12,9,6 all increase homocystine and the Dr looks for increased homocystine levels.
What are the three major metabolic pathways that yield the building blocks for amino acids?
PPP, CAC, and Glycolysis
What are the three amino acids made by alpha-keto acid enzymes?
Alanine, Aspartate, and Glutamate
What is Alanine synthesized from?
Pyruvate
