Rational molecular targeting of the inter-subunit interaction between human cardiac troponin hcTnC and hcTnI using switch peptide-competitive biogenic medicines.

•Biogenic competitors are used to competitively disrupt human cardiac hcTnC–hcTnI interaction.•A multistep screening protocol is performed against a biogenic compound library to identify competitors.•Small-molecule collismycin and compound e are identified as potent competitors.•Both competitors and hcTnI switch peptide share a common binding site of hcTnC.