Patent Number: 
Section: claims

1. A polypeptide comprising at least one helix-loop-helix calcium-binding (EF-hand) motif with deletion of two amino acid residues in the 12-amino-acid calcium-binding loop sequence selected from the group consisting of deletion in positions 1 and 2, and deletion in positions 2 and 3, wherein said polypeptide binds uranyl. 2. The polypeptide of claim 1, wherein said EF-hand motif(s) are derived from signaling EF-hand protein(s) of the calmodulin superfamily selected from the group consisting of calmodulin and troponin C. 3. The polypeptide of claim 1, which comprises two or four EF-hand motifs, wherein at least one EF-hand motif comprises said deletion in the calcium-binding loop sequence, and the other EF-hand motif(s) comprise said deletion or not. 4. The polypeptide of claim 2, which is a calmodulin domain 1 variant comprising two EF-hand motifs, respectively from the EF-hand1 and the EF-hand2 of calmodulin protein(s). 5. The polypeptide of claim 3, which comprises an amino acid sequence selected from the group consisting of SEQ ID NO: 17, 18, 20 and 60. 6. A fusion protein comprising a polypeptide according to claim 1 fused to another protein moiety. 7. The fusion protein of claim 6, which is a cameleon protein comprising tandem fusions of a fluorescence-donor protein, a polypeptide which comprises two or four EF-hand motifs, wherein at least one EF-hand motif comprises said deletion in the calcium-binding loop sequence and the other EF-hand motif(s) comprise said deletion or not, and a fluorescence-acceptor protein. 8. The fusion protein of claim 7, which comprises a sequence selected from the group consisting of SEQ ID NO: 35, 38, 61, 63 and 67. 9. The polypeptide of claim 1 or a fusion protein comprising a polypeptide according to claim 1 fused to another protein moiety, which is immobilized onto a solid support. 10. A polynucleotide encoding the polypeptide of claim 1. 11. A host cell comprising with the polynucleotide of claim 10, wherein the host cell is not an organism. 12. A non-human transgenic organism comprising the polynucleotide of claim 10. 13. A method of detecting uranium contamination in a sample comprising contacting the sample with a uranyl chelating agent comprising:i. the polypeptide of claim 1,ii. a fusion protein comprising a polypeptide according to claim 1 fused to another protein moiety,iii. a host cell comprising a polynucleotide encoding the polypeptide of claim 1 or a fusion protein comprising a polypeptide according to claim 1 fused to another protein moiety, oriv. A non-human transgenic organism comprising a polynucleotide encoding the polypeptide of claim 1 or a fusion protein comprising a polypeptide according to claim 1 fused to another protein moiety, anddetecting the presence of uranyl chelation in the sample. 14. A method of decontaminating or bio-remediating a sample containing uranium comprising contacting the sample with a uranyl chelating agent comprising:i. the polypeptide of claim 1,ii. a fusion protein comprising a polypeptide according to claim 1 fused to another protein moiety,iii. a host cell comprising a polynucleotide encoding the polypeptide of claim 1 or a fusion protein comprising a polypeptide according to claim 1 fused to another protein moiety, oriv. A non-human transgenic organism comprising a polynucleotide encoding the polypeptide of claim 1 or a fusion protein comprising a polypeptide according to claim 1 fused to another protein moiety. 15. The polypeptide of claim 3, which consists of an amino acid sequence selected from the group consisting of SEQ ID NO: 17, 18, 20 and 60. 16. The fusion protein of claim 7, which consists of a sequence selected from the group consisting of SEQ ID NO: 35, 38, 61, 63 and 67. 17. A polynucleotide encoding a fusion protein comprising the polypeptide according to claim 1 fused to another protein moiety.