Question

Which one is an amino acid
A. Pepsin
B. Praline
C. Cysteine
D. Renin

Answer 1

There are 21 amino acids with suitable which are classified according to the core structural functional groups' locations as alpha, beta, gamma, or Delta amino acids; other categories relate to polarity, pH level, and side-chain group type(aliphatic, acyclic, aromatic) containing hydroxyl or sulfur.

Complete answer:
Amino acids are organic compounds that contain amino-alkane (–NH2) and carboxyl (–COOH) functional groups, along with a side chain (R group) specific to each amino. The key elements of an associated amino acid are carbon (C), hydrogen (H), oxygen (O), and nitrogen (N). Amino acids that have amine group attached to the (alpha-) carbon atom next to the carboxyl group have their specific importance. They are generally known as 2-alpha.
Looking at the four options given to us, we can deduce that it has only one amino acid. The first option is Pepsin, which is a protein, hence it's not an amino acid. The second option Praline is also not an amino acid, instead, Proline is an amino acid. The third option Cysteine is an amino acid, as it comes under the list of 21 amino acids. Whereas the last option Renin is also not an amino acid coz it’s a protein.
Cysteine is a semi-essential proteinogenic amino acid with molar mass 121.16 g/mol. Cysteine oxidized with some cellular reactive oxygen species and forms Cysteine Sulfenic acid (-SOH).
So, the correct answer is “Option C”.

Additional Information:
Cysteine is found in highly proteinaceous food elements such as turkey cheese, egg, sunflower oil etc. It also has many beneficial advantages to the human body. It also strengthens hair and helps in hair growth. The body converts cysteine into glucose for a source of energy. Cysteine also plays a role in making a communication bridge between immune system cells.

Note:
Though cysteine helps the body it also causes many diseases such as vomiting, diarrhoea, constipation, nausea. It also rarely reduces blood pressure, causes rashes and headache, fever, rashes, drowsiness and liver problems. A very high amount of cysteine can be toxic to the human body and can cause death.