The article describes the discovery and characterization of hepcidin, a cysteine-rich antimicrobial peptide synthesized in the liver. Hepcidin was initially identified in human urine and characterized as a 20- or 25-amino acid peptide with all 8 cysteines connected by intramolecular disulfide bonds. The full-length prepropeptide contains 84 amino acids, but only the processed forms are found in urine. Hepcidin exhibits antifungal activity against Candida albicans, Aspergillus fumigatus, and Aspergillus niger, and antibacterial activity against Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis, and group B Streptococcus. The gene encoding hepcidin is highly expressed in the liver, and the peptide is not detectable in the kidney or bladder. The authors propose that hepcidin may be a vertebrate counterpart to the cysteine-rich antimicrobial peptides produced in the fat body of insects, such as drosozymic. The study also discusses the potential role of hepcidin in inflammation and host defense, and its possible interaction with specific cellular receptors.The article describes the discovery and characterization of hepcidin, a cysteine-rich antimicrobial peptide synthesized in the liver. Hepcidin was initially identified in human urine and characterized as a 20- or 25-amino acid peptide with all 8 cysteines connected by intramolecular disulfide bonds. The full-length prepropeptide contains 84 amino acids, but only the processed forms are found in urine. Hepcidin exhibits antifungal activity against Candida albicans, Aspergillus fumigatus, and Aspergillus niger, and antibacterial activity against Escherichia coli, Staphylococcus aureus, Staphylococcus epidermidis, and group B Streptococcus. The gene encoding hepcidin is highly expressed in the liver, and the peptide is not detectable in the kidney or bladder. The authors propose that hepcidin may be a vertebrate counterpart to the cysteine-rich antimicrobial peptides produced in the fat body of insects, such as drosozymic. The study also discusses the potential role of hepcidin in inflammation and host defense, and its possible interaction with specific cellular receptors.