formylmethionine

Formylmethionine (f-Met) is a modified amino acid that plays a crucial role in initiating protein synthesis in bacteria and other microorganisms. It is a derivative of methionine, which is an essential sulfur-containing amino acid vital for mammals and fowl as they cannot synthesize it themselves.123

In bacteria like E. coli, the protein assembly process begins with formylmethionine. This modified amino acid is attached to a transfer RNA (tRNA) molecule, which then binds to messenger RNA (mRNA) on a ribosome. This binding event is the first step in translating the genetic code from mRNA into the specific sequence of amino acids that will form a protein. While formylmethionine is essential for initiating protein synthesis in prokaryotes, it is not involved in this process in eukaryotic cells.1