Abstract: The present invention provides a panel of transcriptional activator fusion proteins which comprises both tetracycline controlled transactivator proteins and reverse tetracycline transactivator proteins. These transactivators have novel phenotypes such as altered basal transcriptional activity in the absence of doxycycline, altered induced transcriptional activity in the presence of doxycycline, or differential induction by tetracycline and analogs of tetracycline.

Abstract: The present invention relates a method for monitoring the expression level of a gene in a host cell by modulating the activity of a regulatory biomolecule, comprising the steps of: (a) transforming a cell expressing a regulatory biomolecule with a nucleic acid molecule comprising an open reading frame encoding an interaction partner of said biomolecule in expressible form, wherein (i) said regulatory biomolecule is either a nucleic acid binding molecule that effects its regulatory activity upon binding or an allosterically controlled ribonucleic acid molecule; and (ii) the interaction partner of the biomolecule is encoded by a nucleic acid molecule comprising: (1) a nucleic acid sequence encoding a tagged (poly)peptide, (2) a nucleic acid sequence encoding a tagged (poly)peptide or a peptide tag, a selectable marker gene and additional nucleotide sequences for site specific, in-frame integration of said nucleic acid molecule into the coding sequence of at least one host (poly)peptide of interest, wherein said

Abstract: A method for identifying transcriptional regulatory proteins that modulate the transcription of a gene of interest is disclosed. In one embodiment, the method comprises introducing into a cell a nucleic acid molecule comprising three central components: 1) a polynucleotide (e.g., DNA) encoding a transcriptional regulatory protein; 2) an indicator gene which is responsive to, e.g., under the transcriptional control of, the gene regulatory sequences of a gene of interest which bind to the transcriptional regulatory protein; and 3) a selectable marker gene. The transcriptional regulatory protein binds to the gene regulatory sequences and either activates or inhibits transcription. A protein is identified as a modulator of the transcription of the gene of interest by detecting a signal generated by the indicator gene.

Abstract: The present invention provides a panel of transcriptional activator fusion proteins which comprises both tetracycline controlled transactivator proteins and reverse tetracycline transactivator proteins. These transactivators have novel phenotypes such as altered basal transcriptional activity in the absence of doxycycline, altered induced transcriptional activity in the presence of doxycycline, or differential induction by tetracycline and analogs of tetracycline.

Abstract: The present invention relates to a system for regulating gene expression in prokaryotes using modified tetracycline repressor proteins. In particular, the present invention relates to modified tetracycline repressor proteins that exhibit a “reverse” phenotype in prokaryotic organisms, nucleic acids encoding these repressor proteins, methods for identifying and preparing these proteins, and methods for using these proteins for regulating gene expression in prokaryotic organisms, in drug screening assays and for identifying non-antibiotic compounds that are specific inducers of these modified repressor proteins.

Abstract: A &bgr;-Glucanase enzyme capable of hydrolytically cleaving mixed glucans is presented. The &bgr;-Glucanase is sufficiently stable under alkaline conditions for use in industrial cleaning processes, especially in the brewing industry.

Abstract: Plasmids containing synthetic DNA sequences are described which are suitable for the expression of the intermediate protein of the recombinant scu-PA (i.e., the unglycosylated protein moiety of the single chain prourokinase) in Enterobacteriaceae, especially in E. coli, with expression rates far higher than those obtainable according to prior methods. The plasmids comprise operons that include a regulatable, optionally synthetic, promotor, a Shine-Dalgarno sequence, a start codon, a synthetic structural gene with selected codon usage, and downstream of the structural gene, 1 to 2 transcription terminators. The preparation of the plasmids and of synthetic DNA-sequences starting from commercially available plasmids and intermediates is described. The intermediate protein, expressed in high yields by using the plasmids for transforming suitable hosts, may be refolded to produce the therapeutically useful plasminogen activator recombinant scu-PA.

Abstract: Isolated nucleic acid molecules encoding fusion proteins which regulate transcription in eukaryotic cells are disclosed. The fusion proteins of the invention comprise a Tet repressor having at least one amino acid mutation that confers on the fusion protein an ability to bind a class B tet operator sequence having a nucleotide substitution at position +4 or +6, operatively linked to a polypeptide which regulates transcription in eukaryotic cells. Methods for regulating transcription of a tet operator-linked gene in a cell are also provided.

Abstract: A polypeptide having mutarotase activity is obtained from a host microorganism that has been transformed with a molecule having a recombinant DNA sequence. The molecule having a recombinant DNA sequence is prepared by removing the first 60 nucleotides of a DNA sequence originating from the genome of Acinetobacter calcoaceticus that codes for the polypeptide, modifying the following 21 nucleotides and fusing of the resultant structural gene with the start of the tetracycline-repressor gene and with an effective promotor sequence. The tetracycline-regressor gene and the promotor sequence preferably originate from the same microorganism such as E. coli in which expression of the polypeptide is carried out, and result in increased yield of the expressed polypeptide having mutarotase activity.

Abstract: The invention relates to DNA sequences, recombinant DNA molecules and transformed host organisms, and to their use in a process for the genetic engineering preparation of a polypeptide having the biological activity of the enzyme mutarotase.