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16 Cards in this Set
- Front
- Back
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What is the problem w/ folate as ingested from dietary sources?
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It has lots of extra glutamate residues so can not be absorbed
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How is the folate problem fixed?
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Conjugase enzyme cleaves the extra glutamate residues
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What is the role of dihydrofolate reductase
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reduces folate to dihydrofolate then tetrahydrofolate
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What is methotrexate?
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inhibitor of DHFR
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How do sulfa drugs work?
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inhibit bacterial folate biosynthesis
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What does N5-N10 methylene tetrahydrofolate do?
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Holds onto methyl group
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What happens when serine reacts with tetrahydrofolate?
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Serine rids itself of methyl group which forms N5N10 methylene tetrahydrofolate and turns into glycine
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What happens to glycine when it reacts with tetrahydrofoalte
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CO2 and NH4 are given off and N5-N10 methylene tetrahydrofolate is formed
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How is N5 methyl tetrahydrofolate formed?
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reduction of N5N10 methylene tetrahydrofolate
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What is N5 methyltetrahydrofolate used for?
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in the biosynthesis of methionine by having homocysteine acquire a methyl
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How is N10 formyl tetrahydrofolate formed?
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oxidation and addition of H20 to methylene tetrahydrofolate
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What is used in the biosynthesis of methionine?
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N5 methyl THF (donates a methyl group)
vitamin B12 homocysteine |
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How is adomet formed?
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breakdown of ATP donates the adenine to methionine to form adomet
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What is the role of SAM
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SAM is a biological methylator and donates a methyl group to norEpi to form Epi. ALso in DNA methylation
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HOw do you get from THF to N5 methyl THF
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a carbon donor such as serine or glycine is used to form N5N10 methylene THF. This is then reduced to form N5 THF
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What is a common symptom of a folate deficiency?
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megaloblastic anemia w/ appearance of large immature erythrocytes (megaloblasts) in blood
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