A peptide bond is a chemical bond formed between two molecules when the carboxyl group of one molecule reacts with the amino group of the other molecule, releasing a molecule of water (H2O). This is a dehydration synthesis reaction.
These are organic compounds composed of amine (-NH2) and carboxyl (-COOH) functional groups, along with a side chain (R group) specific to each amino acid. They are the building blocks for proteins.
Large biomolecules or macromolecules consisting of one or more long chains of amino acid residues. Proteins perform vast array functions within organisms including catalyzing metabolic reactions, DNA replication, responding to stimuli, providing structure to cells and organisms, and transporting molecules from one location to another.