Identification and characterization of novel host defense peptides from the skin secretion of the fungoid frog, Hydrophylax bahuvistara (Anura: Ranidae)

Abstract

Two novel peptides (brevinin1 HYba1 and brevinin1 HYba2) were identified from the skin secretion of the frog Hydrophylax bahuvistara, endemic to Western Ghats, India, and their amino acid sequences were confirmed using cDNA cloning and LC/MS/MS. Antibacterial, hemolytic, and cytotoxic activities of brevinin1 peptides and their synthetic analogs (amidated C-terminus) were investigated and compared. All the peptides except the acidic forms showed antibacterial activity against all tested Gram-positive and Gram-negative bacteria. They exhibited low hemolysis on human erythrocytes and showed potent cytotoxic activity against Hep 3B cancer cell line. Upon amidation, the peptides showed increased activity against the tested microbes without altering their hemolytic and cytotoxic properties. The study also emphasizes the need for screening endemic amphibian fauna of Western Ghats, as a potential source of host defense peptides with possible therapeutic applications in the future.

An Amphibian Host Defense Peptide Is Virucidal for Human H1 Hemagglutinin-Bearing Influenza Viruses

“…Harvesting skin secretions was performed as previously described (Vineeth Kumar et al, 2017). Adult H. bavuvistara frogs (both sexes, n = 15) were collected from Kerala, India, under license from the Kerala Forest Department.…”

“…Molecular cloning was performed as previously described (Vineeth Kumar et al, 2017). RNA was isolated from secretions using Dyna beads (Dynal Biotech) and a cDNA library was constructed using SMARTerTMcDNA Amplification Kit (Clontech).…”

Pulling the Brakes on Fast and Furious Multiple Drug-Resistant (MDR) Bacteria

“…These peptides also showed very low hemolysis on human erythrocytes. This study opened up an area to explore more natural sources of host defense peptides, which can be used as effective therapeutic agents [101].…”

Smallest lectin-like peptide identified from the skin secretion of an endemic frog, Hydrophylax bahuvistara

“…The size of the lectin (more than 10 KDa) is one of the major problems which results in toxicity and immunogenicity and hence, shorter lectin-like molecules are at the forefront of the hunt [1]. Cationic host defense peptides (HDP) found in the skin secretion of frogs act as the first line immune defense protecting the animal from microbial infections and predators [7]. Lectin is one such a peptide that can agglutinate bacteria and fungus and is considered as a novel defense mechanism by amphibian immune system [2].…”

“…In the present study, a novel lectin-like peptide having homology to an odorranalectin family of peptides was identified from the skin secretion of Hydrophylax bahuvistara, an endemic frog species of Western Ghats, India. Skin secretion harvesting, molecular cloning and primary structure elucidation of the peptides were done as per standard protocols [7]. Homology search of the peptide sequence was done using BLAST (NCBI), Peptide was chemically synthesized by Fmoc chemistry using CLEAR-amide resin, purity of the synthesized peptide were analyzed by MALDI-TOF-MS. ProtParm (http://expasy.org/tools/protparam.html) and Pepcalc (http:// pepcalc.com/) were used to compute physicochemical properties.…”