Peptides

Short chains of amino acids linked by peptide bonds, typically defined as 2–50 amino acids in length (compared to proteins, which are longer polypeptide chains). Found throughout biology as hormones (insulin, glucagon), neurotransmitters (substance P, neuropeptide Y), antimicrobial agents (defensins, LL-37), and structural components. Research peptides are chemically synthesized versions of naturally occurring or novel peptide sequences studied for their biological effects in preclinical models.