EspF
Disclosed are EspF U (EspF-like polypeptide encoded by a gene of the cryptic prophage CP-933U of enterohemorrhagic E. coli ) polypeptides, fragments thereof, nucleic acids that encode EspF U polypeptides, or fragments thereof, and cells including the polypeptides, fragments, and/or nucleic acids. Also disclosed are model systems, kits, and methods for screening that use, for example, EspF U polypeptides and nucleic acids. Also included are pharmaceutical and diagnostic compositions and methods of diagnosis and treatment of EHEC infections.
1. A purified polypeptide that comprises an amino acid sequence that is at least 97% identical to SEQ ID NO:2, wherein said polypeptide binds to a neuronal Wiskott-Aldrich syndrome protein (N-WASP).
2. The purified polypeptide of claim 1 , wherein the amino acid sequence is at least 98% identical to SEQ ID NO:2.
3. The purified polypeptide of claim 1 , wherein the polypeptide comprises the amino acid sequence of SEQ ID NO:2.
4. The polypeptide of claim 1 , wherein the polypeptide restores actin pedestal formation activity of enteropathogenic Escherichia coli (EPEC) strain KC12.
5. A fusion protein comprising:
(a) the polypeptide of claim 1 ; and
(b) a second polypeptide comprising an amino acid sequence unrelated to the first amino acid sequence.
6. The fusion protein of claim 5 , wherein the second polypeptide comprises a reporter molecule.
7. The fusion protein of claim 5 , wherein the second polypeptide comprises a reporter molecule selected from the group consisting of: a c-myc antigen, at least six consecutive histidines, a chromophore, a fluorophore, a green fluorescent protein, a derivative of green fluorescent protein, biotin, horseradish peroxidase, alkaline phosphatase, β-galactosidase, glucose oxidase, invertase, luciferase, chioramphenicol acetyltransferase, β-glucuronidase, exoglucanase, and glucoamylase.
8. The purified polypeptide of claim 1 , wherein the polypeptide comprises at least amino acids 80 to 384 of SEQ ID NO:2.
9. A purified polypeptide encoded by a nucleic acid at least 98% identical to nucleotides 238-1152 of SEQ ID NO:1.
10. A purified polypeptide that comprises an amino acid sequence that is at least 95% identical to amino acids 80 to 384 of SEQ ID NO:2 (SEQ ID NO:4), wherein said polypeptide binds to a neuronal Wiskott-Aldrich syndrome protein (N-WASP).
11. The purified polypeptide of claim 10 , wherein the amino acid sequence is at least 99% identical to SEQ ID NO:4.
12. The purified polypeptide of claim 10 , wherein the polypeptide comprises the amino acid sequence of SEQ ID NO:4.
13. A method of diagnosing or detecting an enterohemorrhagic Escherichia coli (EHEC) infection, the method comprising:
providing a sample suspected of having an EHEC infection; and
detecting the polypeptide of claim 10 in the sample.
14. The method of claim 13 , wherein the sample is obtained from a subject.
15. A method of diagnosing and treating an enterohemorrhagic Escherichia coli (EHEC) infection, the method comprising:
performing the method of claim 14 ; and
if the polypeptide is detected in the sample, treating the subject with a treatment that does not enhance production of Shiga-like toxin.