Abstract: The present invention relates to expression cassettes suitable for the expression of a heterologous gene. Furthermore, the invention relates to recombinant plasmids comprising such expression cassettes. Also, the invention relates to host cells comprising such cassettes or plasmids. Another embodiment relates to promoters for use in an expression cassette and in heterologous expression systems. Finally, an embodiment relates to methods for the expression of a heterologous gene.

Abstract: The invention relates to methods and means for regulating gene expression and to CodY target sequences. CodY represses its target genes by binding to specific DNA sequences upstream of the respective genes. A conserved target site was identified by analyzing upstream sequences of derepressed genes in a delta codY L. lactis MG1363 derivative, as identified in a DNA micro-array study. Also, CodY target sequences from other gram-positive bacteria, like B. subtilis and Streptococcus are disclosed. Hence, the invention provides CodY target sequences that may be used in different applications to repress or derepress gene expression.

Abstract: Methods for improving binding of a proteinaceous substance to cell-wall material of a Gram-positive bacterium are disclosed. The proteinaceous substance includes an AcmA cell-wall binding domain, homolog or functional derivative thereof. The method includes treating the cell-wall material with a solution capable of removing a cell-wall component such as a protein, lipoteichoic acid or carbohydrate from the cell-wall material and contacting the proteinaceous substance with the cell-wall material.