Fluorogenic/Fluorescent Probes Derivative from Sulfoxanthene, and Use Thereof

A method of detecting, in microorganisms, an enzyme activity selected in the group consisting of nitroreductase, azoreductase, peptidase, glycosidase, esterase and myeloperoxidase activities, comprising the following steps:

• a) providing a reaction medium comprising at least one fluorogenic substrate of formula (I) or (II):
• wherein qu. is a fluorescence quencher group which is chosen in the group consisting of:
• —NO2;
• —N═N—R1;
• R1 being any organic group that does not obscure the corresponding azo bond;
• —NHCO-Pept.;
• Pept. being a peptide residue or any organic group that does not obscure the corresponding amide bond;
• —O-Glyc.;
• Glyc. being an oligoglycoside residue that does not obscure the corresponding glycosidic bond;
• —O—C(O)—R2;
• —O—P(O)(OR2)(OR2′) and —O—S(O)2—R2;
• R2 and R2′ being independently a hydrogen atom or any organic group that does not obscure the corresponding ester bond;
• and
• Ra, Rb, Rc, Rd and Re being independently a hydrogen atom or any organic group that does not obscure the corresponding arylether bond;
• in accordance with the enzyme activity to detect,
• b) inoculating said medium with a biological sample to be tested,
• c) incubating, and
• d) detecting the possible searched enzyme activity by a possible appearance or increase of a fluorescence, visible in the orange, far-red or near infra-red.

A reaction medium for the detection and/or identification of microorganisms, comprising at least one fluorogenic substrate of formula (I) or (II):

• wherein qu. is a selected in the group consisting of:
• —NO2;
• —N═N—R1;
• R1 being any organic group that does not obscure the corresponding azo bond;
• —NHCO-Pept.;
• Pept. being a peptide residue or any organic group that does not obscure the corresponding amide bond;
• —O-Glyc.;
• Glyc. being an oligoglycoside residue that does not obscure the corresponding glycosidic bond;
• —O—C(O)—R2;
• —O—P(O)(OR2)(OR2′) and —O—S(O)2—R2;
• R2 and R2′ being independently a hydrogen atom or any organic group that does not obscure the corresponding ester bond;
• and
• Ra, Rb, Rc, Rd and Re being independently a hydrogen atom or any organic group that does not obscure the corresponding arylether bond.

A fluorogenic or fluorescent compound of formula (I″) or (II″):

• wherein Z is chosen between:
• —NH2 and —OH,
• or in the fluorescence quencher group consisting of:
• —NO2;
• —N═N—R1;
• R1 being any organic group that does not obscure the corresponding azo bond;
• —NHCO-Pept.;
• Pept. being a peptide residue or any organic group that does not obscure the corresponding amide bond;
• —O-Glyc.;
• Glyc. being an oligoglycoside residue that does not obscure the corresponding glycosidic bond;
• —O—C(O)—R2;
• —O—P(O)(OR2)(OR2′) and —O—S(O)2—R2;
• R2 and R2′ being independently a hydrogen atom or any organic group that does not obscure the corresponding ester bond;
• and
• Ra, Rb, Rc, Rd and Re being independently a hydrogen atom or any organic group that does not obscure the corresponding arylether bond so as not to prevent its possible cleavage by a myeloperoxidase activity.