Editing Protein (section)

===Chemical synthesis===

{{main|Peptide synthesis}}

[[File:Peptide Synthesis.svg|thumb|Peptide Synthesis]]

Short proteins can be synthesized chemically by a family of [[peptide synthesis]] methods. These rely on [[organic synthesis]] techniques such as [[chemical ligation]] to produce peptides in high yield.<ref name=Bruckdorfer2004/> Chemical synthesis allows for the introduction of non-natural amino acids into polypeptide chains, such as attachment of [[fluorescent]] probes to amino acid side chains.<ref name=Schwarzer2005/> These methods are useful in laboratory [[biochemistry]] and [[cell biology]], though generally not for commercial applications. Chemical synthesis is inefficient for polypeptides longer than about 300 amino acids, and the synthesized proteins may not readily assume their native [[tertiary structure]]. Most chemical synthesis methods proceed from C-terminus to N-terminus, opposite the biological reaction.<ref name=Kent2009/>