Gallinacins: cysteine-rich antimicrobial peptides of chicken leukocytes.
We purified three homologous antimicrobial peptides ('gallinacins') from chicken leukocytes, examined their antimicrobial activity in vitro, and established their primary sequences by a combination of gas phase microsequencing and on-line LC-ESI-MS analysis of endo- and exoprotease peptide digests. The peptides contained 36-39 amino acid residues, were relatively cationic due to their numerous lysine and arginine residues, and each contained 3 intramolecular cystine disulfide bonds. Gallinacins showed primary sequence homology to the recently delineated beta-defensin family, heretofore found only in the respiratory epithelial cells and neutrophils of cattle, suggesting that beta-defensins originated at least 250 million years ago, before avian and mammalian lineages diverged. The 9 invariant residues (6 cysteines, 2 glycines and 1 proline) common to avian gallinacins and bovine beta-defensins are likely to constitute the essential primary structural motif of this ancient family of host-defense peptides.
Harwig
S S
SS
Department of Medicine, UCLA Center for the Health Sciences 90024.
Swiderek
K M
KM
Kokryakov
V N
VN
Tan
L
L
Lee
T D
TD
Panyutich
E A
EA
Aleshina
G M
GM
Shamova
O V
OV
Lehrer
R I
RI
D000595:Amino Acid Sequence; D000818:Animals; D000890:Anti-Infective Agents / Q000737:chemistry*; D023181:Antimicrobial Cationic Peptides; D030161:Avian Proteins; D001770:Blood Bactericidal Activity; D001798:Blood Proteins / Q000737:chemistry; D002645:Chickens / Q000276:immunology*; D002851:Chromatography, High Pressure Liquid; D003545:Cysteine / Q000737:chemistry; D023082:Defensins; D007962:Leukocytes / Q000737:chemistry*; D008969:Molecular Sequence Data; D010455:Peptides / Q000737:chemistry* / Q000494:pharmacology; D016415:Sequence Alignment; D017386:Sequence Homology, Amino Acid
D000890:Anti-Infective Agents; D023181:Antimicrobial Cationic Peptides; D030161:Avian Proteins; D001798:Blood Proteins; D023082:Defensins; D010455:Peptides; C086738:gallinacin 2 protein, chicken; C086732:gallinacin 1 protein, chicken; D003545:Cysteine