Amino Acids (GATE)
Amino acid metabolism, classification, enzymes, and identification tests
Questions
Which of the following amino acids acts as precursor to hormones epinephrine, norepinephrine and dopamine?
- L-2-Amino-3-(4-hydroxyphenyl)propanoic acid
- 2-Amino-3-hydroxybutanoic acid
- (2S)-2-amino-3-(1H-indol-3-yl)propanoic acid
- Pyrrolidine-2-carboxylic acid
- 2-Amino-3-phenylpropanoic acid
Which of the following acts as metabolic precursor to amino acid aspartate?
- Pyruvate
- Oxaloacetate
- Ribose 5-phosphate
- α-Ketoglutarate
- 3-Phosphoglycerate
Which of the following amino acids are both glucogenic and ketogenic?
- Glycine
- Phenylalanine
- Threonine
- Proline
- Tryptophan
- 1, 2 and 4
- 1, 4 and 5
- 2, 3 and 4
- 2, 3 and 5
- 3, 4 and 5
Desufhydrase deaminates
- cystine
- serine
- threonine
- Only 1
- Only 2
- Only 3
- 1 and 2
- 2 and 3
Which of the following are non-essential amino acids?
- 2-Amino-4-methylpentanoic acid
- Pyrrolidine-2-carboxylic acid
- 2-Aminopropanoic acid
- 2-Amino-3-phenylpropanoic acid
- 2-amino-3-methylbutanoic acid
- L-2-Amino-3-(4-hydroxyphenyl)propanoic acid
- 1, 2 and 5
- 1, 3 and 6
- 2, 4 and 5
- 2, 3 and 6
- 3, 4 and 5
Which of the following statements are not correct regarding transamination?
P. Transamination means transfer of amide nitrogen from a donor molecule to a acceptor molecule.
Q. Liver is the main site for transamination.
R. Transamination reactions are irreversible.
S. Transamination reactions are catalysed by aminotransferases.
- P and Q
- P and R
- P and S
- Q and R
- Q and S
Which of the following is/are anaerobic dehydrogenase(s)?
- L-amino acid oxidase
- D-amino acid oxidase
- Glutamate dehydrogenase
- Only 1
- Only 2
- Only 3
- 1 and 2
- 2 and 3
Which of the following enzymes needs pyrindoxal phosphate as coenzyme?
P. D-amino acid oxidase
Q. Dehydratase
R. Desulfhydrase
S. Glutamate dehydrogenase
- P and Q
- P and R
- P and S
- Q and R
- Q and S
Which of the following amino acids can act as metabolic precursor for synthesis of HO2CCH(NH2)CH2SH and NH2CH2COOH?
- Aspartate
- Glutamate
- Phenylalanine
- Serine
- Threonine
Which of the following is a pair of exclusively ketogenic amino acids?
- Leucine and isoleucine
- Leucine and Lysine
- Lysine and tyrosine
- Isoleucine and lysine
- Leucine and tyrosine
Which of the following amino acids in proteins undergo(es) phosphorylation?
- 2-Amino-3-hydroxypropanoic acid
- 2-Amino-3-hydroxybutanoic acid
- Pyrrolidine-2-carboxylic acid
- Only 1
- Only 2
- Only 3
- 1 and 2
- 2 and 3
Match the following:
| Column – I |
</strong>|<strong>Column – II</strong>|
|A. Alanine|1. α-ketoglutarate|
|B. Glutamine|2. Pyruvate|
|C. Histidine|3. 3-phosphoglycerate|
|D. Serine|4. Ribose 5-phosphate|
- A - 4, B - 3, C - 2, D - 1
- A - 2, B - 1, C - 3, D - 4
- A - 2, B - 1, C - 4, D - 3
- A - 3, B - 2, C - 4, D - 1
- A - 1, B - 2, C - 3, D - 4
Match the following:
| Column – I | Column – II |
| A. Glutamine | 1. K |
| B. Lysine | 2. Q |
| C. Tryptophan | 3. W |
| D. Tyrosine | 4. Y |
- A - 3, B - 4, C - 2, D - 1
- A - 2, B - 1, C - 3, D - 4
- A - 2, B - 3, C - 1, D - 4
- A - 3, B - 2, C - 1, D - 4
- A - 3, B - 1, C - 4, D - 2
Match the following:
| Column – I | Column – II |
| P. Xanthoproteic reaction | 1. Identification of tryptophan |
| Q. Edman’s reaction | 2. Determination of the amino acid sequence of a protein |
| R. Millon’s test | 3. Identification of tyrosine |
| S. Hopkins-Cole test | 4. Detection of aromatic amino acids |
- P – 1, Q – 2, R – 3, S – 4
- P – 1, Q – 2, R – 4, S – 3
- P – 2, Q – 1, R – 4, S – 3
- P – 4, Q – 2, R – 3, S – 1
- P – 4, Q – 3, R – 2, S – 1
Which of the following sets represents essential amino acids?
- Tryptophan, Histidine, Aspartic acid, Proline, Leucine
- Valine, Leucine, Tryptophan, Lysine, Histidine
- Alanine, Proline, Aspartic acid, Glycine, Cysteine
- Valine, Leucine, Aspartic acid, Glycine, Cysteine
- Alanine, Valine, Lysine, Glycine, Tryptophan