Flashcards in Lecture 22 - Folate, B12, and Non-Essential Amino Acids Deck (24)
Name 3 carriers of one-carbon units.
2. Formic acid
Biotin carries the carboxylate group, which is the _________ oxidized carbon.
SAM carries the _________ type of carbons.
A. Most reduced
B. Most oxidized
C. Neither A or B
What are 3 biosynthetic pathways that require one carbon units?
A. Synthesis of non-essential amino acids
B. Synthesis of purines
C. Synthesis of pyrimidines
SAM is involved in the synthesis of which of the following molecules?
D. Methylated DNA and RNA
E. All of the above
What is "SAM" the "preferred carrier" of?
Activated methyl carrier
9 of 11 of the non-essential AAs are synthesized form intermediates in __________ or ________.
2. TCA cycle
___________ is the process of an amino group changing to a ketoacid.
Enzymates that catalyze the formation of an amide bond are usually called:
Glutamate can form what 3 amino acids?
Which glycolytic intermediate forms alanine, a non-essential amino acid?
Name 2 non-essential amino acids are synthesized from essential amino acids.
Cysteine is formed from _________.
Tyrosine is formed from __________.
Maternal PKU is caused by damage to fetus by ___________.
maternal phenylketones (formed when tyrosine can't be synthesized)
Classical PKU presents with a deficiency in ___________.
If untreated, all 3 PKU lead to severe mental retardation. This is due to decreased transport of ______ and __________ across the blood brain barrier.
What are the consequences of a folic acid deficiency?
Inability to carry all one-carbon groups (except methyl); impaired synthesis of compounds that requrie one-carbon units
What two reactions in humans require Vitamin B12?
1. Conversion of L-methylmalonyl-CoA to succinyl-CoA in BCAA metabolism
2. Remethylation of SAM requires Vitamin B12
How does a B12 deficiency result in secondary folate deficiency?
B12 required for conversion of 5-Methyl-THF to THF; so without B12, 5-Methyl-THF builds up and you don't have any usable folate.
_________ is is an amino acid whose plasma concentration is an indicator of functional small intestinal masses.
Homocysteine can be used to regenerate ______, an essential amino acid.
Homocysteine can be used to synthesize ______, a non-essential amino acid.