The invention concerns novel streptavidin muteins and methods of determining, immobilizing, isolating or purifying proteins under denaturing conditions. In one embodiment such a mutein has an Cys residue at sequence position 127 of the wild-type sequence of streptavidin and comprises at least one mutation in the region of the amino acid positions 117 to 121 with reference to the amino acid sequence of wild type streptavidin.

Provided are a TEV protease variant, a fusion protein thereof, a preparation method therefor and the use thereof. Provided are a TEV protease variant with unique properties obtained by screening and a fusion protein thereof. The TEV protease variant has a low enzyme cleavage activity during expression in hosts, and preferably has a lower enzyme cleavage activity compared to an S219V variant having an amino acid sequence as shown in SEQ ID NO: 10. The enzyme cleavage site of the TEV protease variant is selected from EXXYXQG/S/H, wherein X is any amino acid residue, and the enzyme cleavage site is preferably selected from SEQ ID NO: 7 and 8. Fusion expression using the TEV protease variant of the present invention and a polypeptide can be used for preparing a polypeptide quickly and efficiently, thereby solving the problems currently present in the process of the recombinant production of a polypeptide.

The present invention is directed to fluorescent molecular sensor based on Thiazole Orange for protein detection. interaction of the protein target with the molecular sensors of this invention results in a significant increase in the fluorescence emission. The generation of light output signal enables one to detect protein biomarkers associated with different diseases or detecting the protein of interest also in living cells.

Expression vectors and methods of protein purification, which allow for selection of full length protein over truncated forms of the protein being purified, are disclosed. The methods express a target protein as a three domain fusion, represented by formula I: A-[L.sub.1]-B-[L.sub.2]-C, where A is a first purification tag domain, C is the second purification tag domain and B is the target protein domain. A, B and C are preferably covalently linked by linkers, L.sub.1 and L.sub.2 as shown in Formula I, however, L.sub.1 and L.sub.2 may be optional. The purification tags at the N and C termini are different.

Expression vectors including nucleic acid sequences which encode the fusion protein represented by formula I are also disclosed. The vectors are used with host expression systems such as insect, yeast, or mammalian cells to express the target protein, which is subsequently purified as a function of the different affinity tags.

A method for producing a nuclease of a gram negative bacterium or a nuclease preparation containing a nuclease of a gram negative bacterium including expression of the nuclease in a gram positive bacterium and subsequent secretion of the nuclease, as well as a nuclease or a nuclease preparation that can be obtained by this method.

The invention concerns novel streptavidin muteins. In one embodiment such a the mutein (a) contains at least two cysteine residues in the region of the amino acid positions 44 to 53 with reference to the amino acid sequence of wild type streptavidin as set forth at SEQ ID NO: 212 and (b) has a higher binding affinity than (i) a streptavidin mutein “1” (SEQ ID NO: 112) that comprises the amino acid sequence Val.sup.44-Thr.sup.45-Ala.sup.46-Arg.sup.47 (SEQ ID NO: 98), or (ii) wild type-streptavidin of which amino acid residues 14 to 139 are shown as SEQ ID NO: 212 for peptide ligands comprising the amino acid sequence Trp-Ser-His-Pro-Gln-Phe-Glu-Lys (SEQ ID NO: 100).

The invention is in the domain of delivery of molecules to brain cells across the blood-brain barrier. The invention relates to a novel polypeptide-based carrier that allows the efficient delivery of an effector peptide, to neuron cells across the blood-brain barrier, and to methods for the production and testing of such carrier, including a model for testing the capacity of such molecule to cross the blood-brain barrier and/or the toxicity of molecules on the blood brain barrier and/or the capacity of molecules that have crossed to target human brain cells (e/g. neurons, astrocytes and microglial cells).

The invention relates to mutant forms of the outer membrane located lipoprotein CsgG, in particular, modifications at one or more of positions Tyr51; Asn55; and Phe56. The invention also relates to analyte detection and characterisation using said mutant CsgG.

The present invention relates to a producer cell which expresses a tagging protein at the cell surface, such that retroviral vectors produced by the cell are tagged with the tagging protein, wherein the tagging protein comprises: i) a binding domain which binds to a capture moiety ii) a spacer; and iii) a membrane targeting domain such that, when incorporated a retroviral vector, the tagging protein facilitates purification of the retroviral vector from cellular supernatant via binding of the tagging protein to the capture moiety. The present invention also relates to a retroviral vector comprising such a producer cell-derived tagging protein.

This invention relates to a peptide comprising or consisting of at least 8 consecutive amino acid residues of the sequence set forth in SEQ ID NO: 3, provided that said peptide does not consist of the sequence set forth in SEQ ID NO: 3, or a corresponding peptidomimetic, wherein said peptide or peptidomimetic binds to an anti-KIR4.1 antibody comprised in a sample from a patient having multiple sclerosis or a predisposition therefor. The present invention furthermore relates to a method for diagnosing multiple sclerosis or a predisposition for multiple sclerosis in a subject, the method comprising determining the presence of an anti-KIR4.1 antibody in a sample obtained from said subject, wherein the presence of an anti-KIR4.1 antibody in said sample is indicative of multiple sclerosis or a predisposition for multiple sclerosis. Also provided are novel means and methods for the therapy of multiple sclerosis.