Question

What is the structural formula of lysine with pH of 4?

Answer 1

We need to remember that the lysine is an amino acid. But the human body does not make this amino acid. Hence, it must be prepared from the food. And the source of lysine is meat, fish, some of the plants, dairy, eggs, etc.

Complete answer:
We can draw the structural formula of lysine with pH of $4$ is,

We have to know that the predominant structure of lysine is monocationic form. Lysine is an alpha amino acid. But the human body does not make this amino acid. Hence, it must be prepared from the food. And the source of lysine is meat, fish, some of the plants, diary, eggs, etc. And the lysine is used for the synthesis of bio proteins. The lysine contains alpha amino group, alpha carboxylic group and a side chain of lysyl.
We have to remember that the lysine plays a vital role in protein structure. Lysine structure has side chains which have a positively charged group on one end and a long hydrophobic carbon tail near to the backbone that’s why the lysine is called an amphipathic. Lysine has played a major role in biological processes like calcium homeostasis and fatty metabolism.

Note:
We have to remember that the lysine is very important for the biological process like proteinogenesis. Hence, the lack of lysine may lead to the several diseases states like defective connective tissues, impaired fatty acid metabolism, anemia, and systemic protein-energy deficiency. The catabolism of lysine is initiated by the uptake of dietary lysine or from the breakdown of intracellular protein.