Interfering peptides and method for detecting microorganisms

摘要

The invention relates to novel interfering peptides having peptide sequence S with between 7 and 12 amino acids, originating from the peptide sequence of an antigenic protein of a micro-organism M, the sequence S being aligned with a peptide sequence S′ with between 7 and 12 amino acids originating from the peptide sequence of a target protein of a micro-organism M′ that is different from the micro-organism M, provided that: sequences S and S′ have at least 50% identity over their length of 7 to 12 amino acids and at least 4 identical or analogous contiguous amino acids; and their length is identical or they have 1 or 2 different amino acids distributed at one and/or the other end of the sequences. The invention also relates to a method for the in vitro immunoassay-based detection of the presence of a micro-organism M′ or M in a biological sample.

主权项

1. A method for in vitro detection of a microorganism M using a biological sample comprising:
performing an immunoassay that includes contacting the biological sample with an interfering peptide and a binding partner for (i) an antibody AbM directed against a target protein of the microorganism M, or (ii) the target protein of the microorganism M; and determining whether a complex has formed between the binding partner and (i) the antibody AbM, or (ii) the target protein; wherein: formation of the complex indicates that the microorganism M is present; the interfering peptide has a peptide sequence S of 7 to 12 amino acids that is included in the peptide sequence of the target protein of the microorganism M; the sequence S is aligned with respect to a peptide sequence S′ of 7 to 12 amino acids that is included in the peptide sequence of an antigenic protein of an interfering microorganism M′ different from the target microorganism M; the sequences S and S′ exhibit at least 50% identity over their length of 7 to 12 amino acids and at least 4 identical or analogous contiguous amino acids; the sequences S and S′ have identical lengths or exhibit a difference of 1 or 2 amino acids distributed at one and/or the other end of the sequences; the interfering peptide blocks false positive results linked to the presence of antibodies AbM′ directed against the antigenic protein of the interfering microorganism M′; and one of the microorganism M and the microorganism M′ is hepatitis C virus (HCV) and the other of the microorganism M and the microorganism M′ is selected from the group consisting of Staphylococcus aureus, Streptococcus pneumoniae, Bacillus subtilis, Pseudomonas entomophila, and Pseudomonas putida (GB-1 strain); or one of the microorganism M and the microorganism M′ is human immunodeficiency virus HIV-1 and the other of the microorganism M and the microorganism M′ is Mycoplasma pneumoniae.