Kynurenine is synthesized by the enzyme tryptophan dioxygenase, which is made primarily but not exclusively in the liver.

Cecropin B (free acid) is a polypeptide that can be found by peptide screening. Peptide screening is a research tool that pools active peptides primarily by immunoassay. Peptide screening can be used for protein interaction, functional analysis, epitope screening, especially in the field of agent research and development.

H-Gly-His-Arg-Pro-OH