Antimicrobial peptides and protease inhibitors in the skin secretions of the crawfish frog, Rana areolata |
| |
Authors: | Mohamed F Ali Karen R Lips Floyd C Knoop Bernd Fritzsch Caroline Miller J.Michael Conlon |
| |
Affiliation: | 1. Department of Biomedical Sciences, Creighton University Medical School, Omaha, NE 68178, USA;2. Department of Zoology, Southern Illinois University, Carbondale, IL 62901, USA;3. Department of Medical Microbiology and Immunology, Creighton University Medical School, Omaha, NE, 68178, USA;4. Department of Biochemistry, Faculty of Medicine and Health Sciences, United Arab Emirates University, P.O. Box 17666 Al-Ain, United Arab Emirates |
| |
Abstract: | The dorsal skin of the crawfish frog, Rana areolata, is associated with numerous prominent granular glands. Proteomic analysis of electrically stimulated skin secretions from these glands enabled the identification and characterization of eight peptides with antimicrobial and hemolytic activity belonging to the previously identified brevinin-1, temporin-1, palustrin-2, palustrin-3, esculentin-1 (two peptides), and ranatuerin-2 (two peptides) families. The primary structures of the peptides were consistent with a close phylogenetic relationship between R. areolata and the pickerel frog, Rana palustris. Three structurally related cationic, cysteine-containing peptides were identified that show sequence similarity to peptide Leucine–Arginine, a peptide with immunomodulatory and histamine-releasing properties from the skin of the northern leopard frog, Rana pipiens. The skin secretions contained a 61-amino-acid-residue peptide that inhibited porcine trypsin and possessed a 10-cysteine-residue motif that is characteristic of a protease inhibitor previously isolated from the parasitic nematode, Ascaris suum. A 48-amino-acid-residue protein containing eight cysteine residues in the whey acidic protein (WAP) motif, characteristic of elafin (skin-derived antileukoproteinase) and secretory leukocyte protease inhibitor, was also isolated. The data suggest that protease inhibitors in skin secretions may play a role complementary to cationic, amphipathic α-helical peptides in protecting anurans from invasions by microorganisms. |
| |
Keywords: | Antimicrobial peptide Amphibian skin Trypsin inhibitor Elafin |
本文献已被 ScienceDirect 等数据库收录! |
|