FMLP

N-Formylmethionine leucyl-phenylalanine

Names
IUPAC name (2S)-2-[[(2S)-2-[[(2S)-2-Formamido-4-methylsulfanylbutanoyl]amino]-4-methylpentanoyl]amino]-3-phenylpropanoic acid
Other names F-Met-Leu-Phe L-Phenylalanine, N-(N-(N-formyl-L-methionyl)-L-leucyl)-
Identifiers
CAS Number	59880-97-6 Y
3D model (Jmol)	Interactive image
ChemSpider	16125628 Y
IUPHAR/BPS	1022
MeSH	N-Formylmethionine+Leucyl-Phenylalanine
PubChem	443295
InChI InChI=1S/C15H22N2O3.C6H11NO3S/c1-10(2)8-12(16)14(18)17-13(15(19)20)9-11-6-4-3-5-7-11;1-11-3-2-5(6(9)10)7-4-8/h3-7,10,12-13H,8-9,16H2,1-2H3,(H,17,18)(H,19,20);4-5H,2-3H2,1H3,(H,7,8)(H,9,10) Y Key: HFSVAEOILMOWDY-UHFFFAOYSA-N Y InChI=1/C15H22N2O3.C6H11NO3S/c1-10(2)8-12(16)14(18)17-13(15(19)20)9-11-6-4-3-5-7-11;1-11-3-2-5(6(9)10)7-4-8/h3-7,10,12-13H,8-9,16H2,1-2H3,(H,17,18)(H,19,20);4-5H,2-3H2,1H3,(H,7,8)(H,9,10) Key: HFSVAEOILMOWDY-UHFFFAOYAS
SMILES OC(=O)C(NC=O)CCSC.CC(C)CC(N)C(=O)NC(Cc1ccccc1)C(O)=O
Properties
Chemical formula	C21H31N3O5S
Molar mass	437.55 g/mol
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Y  (what is YN ?)
Infobox references

N-Formylmethionyl-leucyl-phenylalanine (FMLP) or N-formyl-met-leu-phe) is a N-formylated tripeptide and sometimes simply referred to as chemotactic peptide is a potent polymorphonuclear leukocyte (PMN) chemotactic factor and is also a macrophage activator.

FMLP is the prototypical representative of the N-fomylated oligopeptide family of chemotactic factors. These oligopeptides are known to be, or mimic the actions of, the N-formyl oligopeptides that are (a) released by tissue bacteria, (b) attract and activate circulating blood leukocytes by binding to specific G protein coupled receptors on these cells, and (c) thereby direct the inflammatory response to sites of bacterial invasion. FMLP is involved in the innate immunity mechanism for host defense against pathogens.

FMLP led to the first discovery of a leukocyte receptor for a chemotactic factor, defined three different types of FMLP receptors that have complimentary and/or opposing effects on inflammatory responses as well as many other activities, and helped define the stimulus-response coupling mechanisms by which diverse chemotactic factors and their G protein coupled receptors induce cellular function.

In 1887, Élie Metchnikoff observed that leukocytes isolated from the blood of various animals were attracted towards certain bacteria. This attraction was soon proposed to be due to soluble elements released by the bacteria (see Harris for a review of this area up to 1953). Peter Ward, Elmer Becker, Henry Showell, and colleges showed that these elements were made by a variety of growing gram positive bacteria and gram negative bacteria and were of low molecular weight, i.e. below 3600 Dalton (unit)s. Further studies by Schiffmann and colleges found that cultures of growing Escherichia coli released oligopeptides of between 150 and 1500 daltons that appeared to have a free Carboxylic acid group but not a free Amine group.