Polypeptide sequence of an ABC transporter of Toxoplasma gondii useful for detecting T. gondii infections and other members of the ABC transporter family and for reducing intracellular concentrations of cytotoxic compounds

摘要

Transmembrane transport polypeptide or its fragment (I) from Toxoplasma gondii of the ABC family of transporter proteins comprises at least one domain similar to a Walker A domain represented by the sequence X-Gly-Ser-Gly-Lys-Thr-Thr or a Walker B domain represented by the sequence Val-Leu-Ile-Leu-Asp-Glu-Ala-Thr-Ser-Ser or at least one domain similar to a Walker A or B domain represented by these sequences. Transmembrane transport polypeptide (I) from Toxoplasma gondii of the ABC family of transporter proteins comprises at least one domain similar to a Walker A domain represented by the sequence X-Gly-Ser-Gly-Lys-Thr-Thr (SEQ. ID No.1) or a Walker B domain represented by the sequence Val-Leu-Ile-Leu-Asp-Glu-Ala-Thr-Ser-Ser (SEQ ID No.2) or at least one domain similar to a Walker A or B domain represented by these sequences. (I) further comprise at least one domain similar or identical to the "signature ABC transporter" sequence Leu-Ser-Gln-Gly-Glu-Arg-Gln-Leu-Leu-Ser-Ile-Thr-Arg-Ala (SEQ ID No.3) in addition or instead of SEQ IDs No.1 and 2 above. (I) may also comprise the sequence known as the "Glutamine loop", comprising the sequence Val-Leu-Gln-Asp. (I) may also comprise the 133 residue amino acid sequence known as TgABC1 (SEQ ID NO.6) fully disclosed in the specification (X not defined). (I) may further comprise a sequence of at least 8 consecutive amino acids chosen from: Val-Leu-Ile-Leu-Asp-Glu-Ala-Thr-Ser-Ser; Leu-Ser-GLn-Gly-Glu-Arg-Gln-Leu; and Leu-Ser-Gln-Gly-Glu-Arg-Gln-Leu-Leu-Ser-Ile-Thr-Arg-Ala. Independent claims are also included for: (1) polypeptide fragment comprising at least 8 consecutive amino acids forming a characteristic sequence specific to an ABC transporter protein belonging to at least one strain of T. gondii; (2) polynucleotide (II) encoding (I); (3) vector (III) for cloning or expression of any polypeptide sequences of (I); (4) host cell (IV) comprising (III); (5) oligonucleotide probes (V) for specifically detecting a T. gondii infection comprising a nucleotide sequence chosen from: (i) GCT TCT GGG AAA ACA AC; (ii) GTA TTA CAA GAT; (iii) TTA AGT CAA GGR GAA CGT; and/or (iv) GAT GAA GCC ACA TCA TCA; (6) antibodies (VI) specific for (I); (7) preparation (M1) of (VI); (8) in vitro detection (M2) of active compounds against invasion and/or replication of T. gondii in a host cell; and (9) screening (M3) molecules interacting with (I).