Table 2. Binding affinity and potency of bacterial and mitochondrial formyl peptides.
pEC50 is defined as the negative logarithm of the EC50. HL-60 cells transfected to express FPR1 or FPR2/ALX, and Chinese hamster ovary cells (CHO) transfected to express FPR1, were used in some studies.
| Ligand | Origin | Assay | Potency | Cells (receptors) | Reference |
|---|---|---|---|---|---|
| N-formyl-Met-Leu-Phe | E. coli | Chemotaxis | pEC50 = 10.15 | Neutrophils | (Showell et al., 1976; Freer et al., 1980) |
| Lysozyme release | pEC50 = 7.49 | Neutrophils | (Freer et al., 1980) | ||
| O2 − production | pEC50 = 7.00 | Neutrophils | (Boxer et al., 1979) | ||
| Binding | pKd = 9.28–7.61 | Neutrophils | (Koo et al., 1982) | ||
| pKd = 6.37 | Transfected cells (FPR2/ALX) | (Quehenberger et al, 1993) | |||
| N-formyl-Met-Ile-Phe-Leu | S. aureus | Chemotaxis | pEC50 = 7.51 | Monocytes | (Rot et al., 1987) |
| Competitive binding | pIC50 = 8.01 | Monocytes | (Rot et al., 1987) | ||
| O2 − production | pEC50 = 8.00 | Neutrophils (mFpr1) | (Southgate et al., 2008) | ||
| N-formyl-Met-Ile-Val-Ile-Leu | L. monocytogenes | Ca2+ flux | pEC50 = 8.66 | HL-60 (FPR1) | (Rabiet et al., 2005) |
| pEC50 = 6.80 | HL-60 (FPR2/ALX) | (Rabiet et al., 2005) | |||
| O2 − production | pEC50 = 7.82 | Neutrophils (mFpr1) | (Southgate et al., 2008) | ||
| N-formyl-Met-Ile-Gly-Trp-Ile | L. monocytogenes | Ca2+ flux | pEC50 = 7.70 | HL-60 (FPR1) | (Rabiet et al., 2005) |
| pEC50 = 6.68 | HL-60 (FPR2/ALX) | (Rabiet et al., 2005) | |||
| N-formyl-Met-Ile-Val-Thr-Leu-Phe | L. monocytogenes | Ca2+ flux | pEC50 = 8.57 | HL-60 (FPR1) | (Rabiet et al., 2005) |
| pEC50 = 6.70 | HL-60 (FPR2/ALX) | (Rabiet et al., 2005) | |||
| N-formyl-Met-Ile-Gly-Trp-Ile-Ile | L. monocytogenes | Ca2+ flux | pEC50 = 7.40 | HL-60 (FPR1) | (Rabiet et al., 2005) |
| N-formyl-Met-Phy-Glu-Asp-Ala-Val-Ala-Trp-Phy | M. avium | Chemotaxis | pEC50 = 6.00 | CHO (FPR1) | (Gripentrog et al., 2008) |
| N-formyl-Met-Met-Tyr-Ala-Leu-Phe | Mitochondria, ND6 | Ca2+ flux | pEC50 = 7.92 | HL-60 (FPR1) | (Rabiet et al., 2005) |
| pEC50 = 7.82 | HL-60 (FPR2/ALX) | (Rabiet et al., 2005) | |||
| N-formyl-Met-Leu-Lys-Leu-Ile-Val | Mitochondria, ND4 | Ca2+ flux | pEC50 = 7.92 | HL-60 (FPR1) | (Rabiet et al., 2005) |
| pEC50 = 7.26 | HL-60 (FPR2/ALX) | (Rabiet et al., 2005) | |||
| N-formyl-Met-Tyr-Phe-Ile-Asn-Ile-Leu-Thr-Leu | Mitochondria, ND1 | Binding | pKd = 9.00 | CHO (FPR2/ALX) | (Chiang et al., 2000) |
| N-formyl-Met-Phe-Ala-Asp-Arg-Trp | Cytochrome C oxidase subunit | Ca2+ flux | pEC50 = 6.80 | HL-60 (FPR1) | (Rabiet et al., 2005) |
| pEC50 = 6.68 | HL-60 (FPR2/ALX) | (Rabiet et al, 2005) |