Interfering peptides and method for detecting microorganisms

Patent metadata

Field	Value
Publication number	US-9606120-B2
Application number	US-201314380790-A
Country	US
Kind code	B2
Filing date	Mar 11, 2013
Priority date	Mar 9, 2012
Publication date	Mar 28, 2017
Grant date	Mar 28, 2017

Abstract

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.

First claim

The invention claimed is:

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 Ab M 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 Ab M , 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 Ab M′ 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.

2. 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 Ab M′ 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 Ab M′ , 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 an antigenic protein of an interfering microorganism M different than 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 the target protein of the 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 Ab M 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.

3. The method according to claim 1 , wherein the sequences S and S′ have from 8 to 10 amino acids.

4. The method according to claim 2 , wherein the sequences S and S′ have from 8 to 10 amino acids.

5. The method according to claim 1 , wherein the microorganism M is the hepatitis C virus (HCV), 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).

6. The method according to claim 2 , wherein the microorganism M′ is the hepatitis C virus (HCV), 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).

7. The method according to claim 1 , wherein the peptide having sequence S is selected from the group consisting of Y7E-1 having sequence SEQ ID NO. 1, A8E having sequence SEQ ID NO. 3, Y7E-2 having sequence SEQ ID NO. 5, D8E having sequence SEQ ID NO. 6, and E8E having sequence SEQ ID NO. 4.

8. The method according to claim 2 , wherein the peptide having sequence S is selected from the group consisting of Y7E-1 having sequence SEQ ID NO. 1, A8E having sequence SEQ ID NO. 3, Y7E-2 having sequence SEQ ID NO. 5, D8E having sequence SEQ ID NO. 6, and E8E having sequence SEQ ID NO. 4.

9. The method according to claim 1 , wherein the microorganism M is the human immunodeficiency virus HIV-1, and the microorganism M′ is Mycoplasma pneumoniae.

10. The method according to claim 2 , wherein the microorganism M′ is the human immunodeficiency virus HIV-1, and the microorganism M is Mycoplasma pneumoniae.

11. The method according to claim 1 , wherein the peptide having sequence S is selected from the group consisting of E8L-1 having sequence SEQ ID NO. 7 and E8L-2 having sequence SEQ ID NO. 8.

12. The method according to claim 2 , wherein the peptide having sequence S is selected from the group consisting of E8L-1 having sequence SEQ ID NO. 7 and E8L-2 having sequence SEQ ID NO. 8.

13. The method according to claim 1 , wherein the interfering peptide is not the peptide V7E having sequence SEQ ID NO. 2.

14. The method according to claim 1 , wherein the binding partner is derived from the target protein against which the antibody Ab M is directed or the binding partner is the target protein; and the binding partner includes the peptide sequence S.

15. The method according to claim 2 , wherein the interfering peptide is not the peptide V7E having sequence SEQ ID NO. 2.

16. The method according to claim 2 , wherein the binding partner is derived from the target protein against which the antibody Ab M′ is directed or the binding partner is the target protein; and the binding partner includes the peptide sequence S′.

17. The method according to claim 1 , wherein the microorganism M is selected from the group consisting of Staphylococcus aureus, Streptococcus pneumoniae, Bacillus subtilis, Pseudomonas entomophila , and Pseudomonas putida (GB-1 strain); and the microorganism M′ is hepatitis C virus (HCV).

18. The method according to claim 2 , wherein the microorganism M is hepatitis C virus (HCV), 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).

19. The method according to claim 1 , wherein the microorganism M is Mycoplasma pneumoniae , and the microorganism M′ is the human immunodeficiency virus HIV-1.

20. The method according to claim 2 , wherein the mic

Assignees

• Biomerieux Sa
• Biomerieux Sa

Inventors

• Bettsworth Florence
• Pothion Catherine
• Seigneres Béatrice

Classifications

• G01N33/5306 Primary

  Improving reaction conditions, e.g. reduction of non-specific binding, promotion of specific binding · CPC title

• G01N2469/10

  Detection of antigens from microorganism in sample from host · CPC title

• G01N33/54393

  Improving reaction conditions or stability, e.g. by coating or irradiation of surface, by reduction of non-specific binding, by promotion of specific binding · CPC title

• G01N33/56911

  Bacteria · CPC title

• G01N33/56983 Primary

  Viruses · CPC title