Oreoch-1: A Peptide from Oreochromis niloticus as a Potential Tool against Staphylococci

Abstract

Staphylococci, including Staphylococcus aureus and Staphylococcus epidermidis, are important human pathogens associated with potentially life-threatening infections. Their great biofilm-producing ability and the development of resistance mechanisms often account for therapeutic failure. Hence, the scientific community has devoted intensive efforts to the development of antimicrobial compounds active against both planktonic and sessile bacterial populations. Contextually, antimicrobial peptides (AMPs) are natural peptides produced by the innate immunity of every organism, representing a potential new therapeutic solution against human microbial pathogens. Our work focused on the in vitro activity of Oreoch-1, an AMP from the gills of Nile tilapia (Oreochromis niloticus), against standard and clinical S. aureus and S. epidermidis strains. Firstly, the cytotoxicity profile of Oreoch-1 was determined in human colon carcinoma cells. Secondly, its antibacterial spectrum was explored against staphylococcal strains to set up the minimum inhibitory concentration (MIC) and the minimum bactericidal concentration (MBC). Our results highlighted an antibacterial activity in the range 6.25–25 μM, with a general bacteriostatic effect. Therefore, the biofilm-inhibitory property was assessed against S. aureus ATCC 25923 and S. epidermidis ATCC 35984, indicating a significant reduction in S. aureus biomass at sub-MIC concentrations. Overall, our study indicates Oreoch-1 as a promising new therapeutic weapon against staphylococcal infections.

Oreoch‐1: A broad‐spectrum virus and host‐targeting peptide against animal infections

“…Oreoch-1 (single-letter amino acid sequence: FIHHIIGGLLFSVGKHIH-GLIHGH) was synthesized as a C-terminal amidated peptide following as reported elsewhere. 29,30 In detail, we used a fully automated and computer-controlled Syro I multiple peptide synthesizer from Multi-SynTech GmbH (Witten, Germany) equipped with a 24-position One U-Typ reactor block with 5 mL reactors. The peptide was synthesized using the solid-phase method at 50 μmol scale following the Fmoc strategy, using Fmoc-derivatized standard amino acids and a Rink amide MBHA resin (0.35 mmol/g substitution) as the solid support.…”

“…The identity and quality of the synthetic peptide by RP-HPLC and mass spectroscopy were validated (Table 1). 29…”

“…25 In the last years, several studies have highlighted the significant antibacterial properties of different piscidins, evidencing their potential as novel and valuable weapons in the fight against microbial diseases. [24][25][26][27][28][29] The present study aims to investigate for the first time the antiviral activity of oreochromicin-1 (oreoch-1), particularly against animal viruses such as canine distemper virus (CDV), Schmallenberg virus (SBV), and two animal herpesviruses (HVs), the caprine type 1 (CpHV-1) and the bovine type 1 (BoHV-1). By shedding light on the mechanisms of action and efficacy of oreoch-1, we aim to contribute valuable insights into the control of zoonotic diseases, ultimately improving both human and animal health care.…”

“…The purity of the peptide was estimated to be greater than 95%. The peptide was solubilized in sterile water and stored at À20 C until use 29. Cell culture and viral strain Vero/hSLAM cells (ECACC 04091501, based in Porton Down, United Kingdom), baby hamster kidney cells (BHK-21, ATCC CCL-10, located in Manassas, VA, USA), and Madin Darby bovine kidney cells (MDBK, ATCC CCL-22) were grown in Dulbecco's modified Eagle medium (DMEM) containing 4.5 g/L glucose and supplemented with 100 IU/mL penicillin, 100 μg/mL streptomycin, and 10% FBS.…”