Proteins Natural polymers composed reactions

Proteins are polymers formed from peptides in condensation reactions. Condensation of two amino acids means that the OH group of carboxyl of one peptide and a hydrogen of the amino group of the other expel a water molecule and form a peptide bond (Figure 9.4). Further condensation reactions lead to the protein. The sequence of peptides is referred to as the primary structure of the protein. The 20 amino adds composing natural proteins are given in Table 9.3. 

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