What are Peptides?

Peptides are natural or synthetic molecules comprising two or more amino acids linked through amide formation. In peptides, amino acids are linked in sequence by a covalent chemical bond between a carboxyl group of one amino acid and a nitrogen atom of another amino acid. Peptides differ from proteins based on the number of amino acid residues. The shortest peptides are called dipeptides consisting of two amino acids joined together by a single peptide bond. Polypeptides comprised of 10-50 amino acid residues are called peptides. Peptides containing more than 50 amino acids often are referred to as proteins. Also, peptides and proteins can be classified by function or by synthesis. Peptides classified by function include hormones, neuropeptides, HLA peptides, infectious disease, cancer peptides, and many others.

Synthetic peptides are now significant commercial and pharmaceutical products. Examples of synthetic peptides are the dipeptide sugar substitute aspartame and hormones used in the clinic, including oxytocin, the adrenocorticotropic hormone, and calcitonin.

The list of applications of synthetic peptides includes the development of epitope-specific antibodies against pathogenic proteins, the study of protein functions, and the identification and characterization of proteins. Furthermore, synthetic peptides allow studying enzyme-substrate interactions within important enzyme classes, such as kinases and proteases, which play a crucial role in cell signaling.

In cell biology, sets of homologous synthetic peptides enable studying receptor binding or the substrate recognition specificity of newly discovered enzymes. 
Synthetic peptides can resemble naturally occurring ones and act as drugs against cancer and other diseases.

Also, mass spectrometry (MS)-based applications utilize synthetic peptides as standards and reagents. Importantly, synthetic peptides play a central role in the MS-based discovery, characterization, and quantitation of proteins, especially those that serve as early biomarkers for diseases.

Bio-Synthesis offers two strategies for peptide synthesis: liquid-phase peptide synthesis and solid-phase Fmoc peptide synthesis (SPPS). Contact us for your peptide research needs.