Dermcidin
Dermcidin is a protein with 110 amino acids that in humans is encoded by the DCD gene. The full-length protein produces derived peptides as proteolysis-inducing factor and other anti-microbial peptides, secreted by human eccrine sweat glands onto the skin as a part of the innate host defense of the immune system. PIF is involved in muscular proteolysis.
Function
Dermcidin is a secreted protein that is subsequently processed into mature peptides of distinct biological activities. The C-terminal peptide is constitutively expressed in sweat and has antibacterial and antifungal activities. The N-terminal peptide, also known as diffusible survival evasion peptide, promotes neural cell survival under conditions of severe oxidative stress. A glycosylated form of the N-terminal peptide may be associated with cachexia in cancer patients.Survival evasion peptide Antimicrobial peptide
YDPEAASAPGSGNPCHEASAAQKENAGEDPGLARQAPKPRKQRSSLLEKGLDGAKKAVGGLGKLGKDAVEDLESVGKGAVHDVKDVLDSVL
The C-terminal precursor DCD-1L is a 48 residue peptide that shows partial helicity in solution, as evidenced by the determination of its solution structure by NMR and CD-spectroscopy. The full length precursor is processed by undetermined proteases present in human sweat, to form several shorter peptides that show variable antimicrobial activity, named according to their C-terminal triplet of amino acids and their residue length. One such active peptide is SSL25, which shows a 2-fold increase in activity against E. coli compared to DCD-1L.
DCD-1L SSLLEKGLDGAKKAVGGLGKLGKDAVEDLESVGKGAVHDVKDVLDSVL
DCD-1 SSLLEKGLDGAKKAVGGLGKLGKDAVEDLESVGKGAVHDVKDVLDSV
SSL25 SSLLEKGLDGAKKAVGGLGKLGKDA