What Does Polypeptides Mean?
Polypeptides are long chains of chemically linked amino acids. Shorter amino acid chains are referred to as peptides. These compounds are so named because of the type of chemical bond linking the amino acids together, referred to as an amide or peptide bond.
While a peptide may consist of just two amino acids bonded together, a combination of ten or more amino acids is necessary for a compound to be classified as a polypeptide. Additionally, polypeptides usually have a molecular weight greater than 10,000.
While both polypeptides and peptides are proteins, biologists tend to use the term protein only when referring to the polypeptides. Most polypeptides are not only longer but more structurally complex than peptides.