Characterization of a novel peptide from pathogenic Leptospira and its cytotoxic effect

Journal article

Leptospirosis is a zoonotic infectious disease caused by pathogenic Leptospira species. Virulence proteins have been shown to be key determinants of the pathogenesis of pathogenic Leptospira. A specific peptide at a mass-to-charge ratio of 7000 Da was identified in Leptospira whole cells using matrix-assisted laser/desorption ionization time-of-flight (MALDI-TOF) mass spectrometry. This peptide was specifically present in pathogenic Leptospira and in clinical isolates. We report here the characterization of this specific peptide using a proteomics approach. This peptide was significantly matched to a hypothetical conserved L. interrogans protein (LA2458) with a calculated molecular weight of 7140.136 Da containing a tellurite-resistance domain at its C terminus (TerB-C). The amino acid sequences revealed the presence of hydrophobic transmembrane portions and two linear B-cell epitopes. Despite its low abundance, this synthetic peptide demonstrated dose-dependent cytotoxicity toward African green monkey kidney (Vero) cells via the apoptosis pathway. The concentration of the peptide 100 µM induced about 50% of cell death after a 24 h exposure. This peptide could be useful for the diagnosis of leptospirosis and the study of pathogenesis.

Authors: Paratsaphan, S; Moonsom, S; Reamtong, O; Roytrakul, S; Wuthiekanun, V

• Publication status: Published
• Peer review status: Peer reviewed
• Publisher: MDPI
• Journal: Pathogens
• Volume: 9
• Issue: 11
• Article number: 906
• Publication date: 2020-10-30
• Acceptance date: 2020-10-21
• DOI: 10.3390/pathogens9110906
• EISSN: 2076-0817
• Pmid: 33142957
• Language: English
• Keywords: pathogenic Leptospira; FFR; novel peptide; cytotoxicity