Synthetic Peptide for S. mansoni Protein

A synthetic peptide (SLPSNAHNNDNNSSD-biotin) containing amino acids 216–230 from the S. mansoni protein Smp150390.1 (Carvalho et al., 2017 (link)) was purchased from Biomatik (Ontario, Canada) and conjugated with biotin at the C-terminal end. The synthetic peptide had a purity of 96.22% and was resuspended in ultra-pure water to a final concentration of 2.5 mg/ml and stored at-70°C until use. A S. mansoni recombinant protein, called by the name PPE (rPPE), and encoded by a sequence similar to the Smp_049300.3 gene, was expressed in E. coli ArcticExpress (DE3) cells (Agilent Technologies, Santa Clara, CA, United States) using the pET21a plasmid and purified by Ni²⁺ affinity chromatography using the Ni-NTA Fast Start Kit (Qiagen GmbH, Hilden, Germany). The resulting purified rPPE was stored at-70°C in PBS at 1 mg/ml until use.