Amino Acids

Question 1

Nonpolar AA

Answer 1

Ala, Gly, Ile, Leu, Met, Phe, Pro, Trp, Tyr

Question 2

Polar AA

Answer 2

Uncharged: Asn, Cys, Gln, Ser, Thr
Acidic: Asp, Glu
Basic: His, Arg, Lys

Question 3

AA Metabolism

Answer 3

Breaks down to either ketone bodies or glucose

Question 4

ALT & AST

Answer 4

Transaminases located in muscle and liver; if in blood, disease

Question 5

Methionine metabolism

Answer 5

Methionine converted to SAM then to homocysteine; homocysteine can either be recycled to methionine using methyl group from folate and B12 OR converted to (B6 required) cystothionine; error in either pathway causes buildup of homocysteine which is toxic to vasculature

Question 6

BCAA Metabolism

Answer 6

Val, Ile, Leu; converted to keto-acid via transamination; further metabolized via BC alpha keto DH; deficiency causes buildup of ketoacid - Maple Syrup Urine Disease; can also have deficiency in cofactor, thiamine.

Question 7

Phe Metabolism

Answer 7

Phe converted to Tyr via phenylalanine hydroylase; deficit causes buildup of Phe; Tyr becomes essential AA; production of melanin, dopamine, and fumarate also effected b/c Tyr precursor

Question 8

AA derivatives

Answer 8

Tyr —- melanin; involves tyrosinase (albino lacks)
Tyr —- thyroid hormones
Cys —- glutathione

Question 9

Where are BCAA degraded?

Answer 9

Muscle, kidney, brain NOT LIVER - does not have aminotransferase