Role of lysine residue at 7th position of wasp chemotactic peptides.

Most of chemotactic peptides isolated from various kinds of wasp venom have lysine residue at 7th (or 8th) position, but only a chemotactic peptide from Icaria sp. has no basic amino acid residues in the sequence. The relation of chemotaxis with other biochemical activities such as superoxide generation and lysosomal enzyme release from guinea pig neutrophils was studied by the use of substitution analogs of Icaria chemotactic peptide at 7th position. Findings revealed two distinct ways of chemoattractant signal transduction in neutrophils.