About PKU and amino acids


 

 

 

 

(Q AM-06) H.C, a 4 month-old male infant, emigrated with his parents from a Latin American country to the United States a month ago. He was normal at birth but in the past several days a tremor in his extremities has appeared. Last night he presented gross twitching movements in his crib. When you examine the patient, you note a musty odor to the baby’s wet diaper.

 

Immediately you order a screening test for PKU and it results positive.

 

Besides diet restrictions, but warranting an appropriate amount of the essential amino acids, which of the following amino acids you should supplement in higher quantities than in a normal diet, since it is essential for this patient?

 

a)     Alanine

 

b)     Asparagine

 

c)      Aspartate

 

d)     Glutamate

 

e)     Phenyl alanine

 

f)       Serine

 

g)     Tyrosine

 

Answer

 

     

About Protein Classification


 

From Ethan Hein in Flickr

 Helices in a protein

 

Q: A protein X is formed by two chains with 80 amino acids in one chain and 58 in the other. These two chains are linked by disulfide bonds and all the essential amino acids are present in the structure, but not all the non-essential amino acids.  With this information, we can say that this protein is:

 

a) a globular protein

 

b) a fibrous protein

 

c) a conjugated protein

 

d) an incomplete protein

 

e) a complete protein

 

f) a hormone

 

g) an enzyme

 

 

     Answer

 

 

More questions about amino acid metabolism


 

Q: AM-02

 

An amino acid that yields acetoacetyl CoA during the catabolism of its carbon skeleton would be considered:

 

a)     glycogenic

b)     ketogenic

c)      glycogenic and ketogenic

d)     neither glycogenic nor ketogenic

e)     essential

f)       non essential

 

Answer to AM-02

 

 

Q: AM-03

 

The necessary coenzyme for transamination reactions is:

 

a)     NAD

b)     FAD

c)      FMN

d)     Pyridoxal Phosphate

e)     Thiamine Pyrophosphate

f)       Coenzyme A

g)     tetrahydrobiopterin

h)    Folate

 

Answer to AM-o3

 

 

Q: AM-04

 

The NH3 produced in muscle degradation of nitrogenated compounds is transported through blood to the liver using as carriers:

 

a)     alanine and glutamine

b)     urea and alanine

c)      NH4 and glutamate

d)     Glutamate and glutamine

e)     Alpha-ketoglutarate and urea

 

Answer to AM-04

 

 

Q: AM-05

 

Nitric oxide and urea have in common the fact that they both have as an immediate precursor the amino acid:

 

a)     Aspartate

b)     arginine

c)      glutamate

d)     phenylalanine

e)     tyrosine

f)       tryptophan

 

 Answer to AM-05

 

 

Q: About a baby with PKU (AM-01)


H.C, a 4 month-old male infant, emigrated with his parents from a Latin American country to the United States a month ago. He was normal at birth but in the past several days a tremor in his extremities has appeared. Last night he presented gross twitching movements in his crib. When you examine the patient, you note a musty odor to the baby’s wet diaper.

 

Immediately you order a screening test for PKU and it results positive. Which of the following compounds can you expect that is elevated in this patient urine?

 a)     phenyl lactate
 
b)     leucine
 
c)      methyl propionate
 
d)     arginino succinate
 
e)     vanillyl mandelate
 
f)       Homogentisate 

 

 

 

 

 

 Answer