Identification and Screening of Potent Antimicrobial Peptides in Arthropod Genomes

Publication date: Available online 1 March 2018 Source:Peptides Author(s): Deepesh Duwadi, Anishma Shrestha, Binyam Yilma, Itamar Kozlovski, Munaya Sa-eed, Nikesh Dahal, James Jukosky Using tBLASTn and BLASTp searches, we queried recently sequenced arthropod genomes and expressed sequence tags (ESTs) using a database of known arthropod cecropins, defensins, and attacins. We identified and synthesized 6 potential AMPs and screened them for antimicrobial activity. Using radial diffusion assays and microtiter antimicrobial assays, we assessed the in vitro antimicrobial effects of these peptides against several human pathogens including Gram-positive and Gram-negative bacteria and fungi. We also conducted hemolysis assays to examine the cytotoxicity of these peptides to mammalian cells. Four of the six peptides identified showed antimicrobial effects in these assays. We also created truncated versions of these four peptides to assay their antimicrobial activity. Two cecropins derived from the monarch butterfly genome (Danaus plexippus), DAN1 and DAN2, showed minimum inhibitory concentrations (MICs) in the range of 2–16 μg/ml when screened against Gram-negative bacteria. HOLO1 and LOUDEF1, two defensin-like peptides derived from red flour beetle (Tribolium castaneum) and human body louse (Pediculus humanus humanus), respectively, exhibited MICs in the range of 13–25 μg/mL against Gram-positive bacteria. Furthermore, HOLO1 showed an MIC less than 5 μg/mL again...

Source: Peptides - March 2, 2018 Category: Biochemistry Source Type: research