What is the chemical composition of proteins?

1 Answer


Proteins are organic compounds which are polymers of amino acids.


There are 20 different amino acids which make up proteins. Each amino acid consists of a central carbon. The central carbon is bonded to an amine group (#NH_2#), a carboxyl group (COOH), a hydrogen atom and an R group.


Amino acids can be linked together when the amine group of one amino acid is bonded to the carboxyl group of a different amino acid. The COOH donates an OH group and the #NH_2# donates a H. The OH and H come together to form a water molecule, so this process is called dehydration synthesis - water is removed to form something new. The bond which holds the amino acids together is called a polypeptide.

Here's a video which summarizes key concepts students should know about proteins for a high school biology class.

Video from: Noel Pauller

Hope this helps!