摘要:
The invention provides a fed-batch or continuous process for producing heterologous peptides, polypeptides or proteins in lactic acid bacteria, comprising the steps of (i) constructing a recombinant lactic acid bacterium comprising a nucleotide sequence coding for the heterologous peptide, polypeptide or protein, and appropriate regulatory nucleotide sequences such as regulatable promoters and signal peptides to control the expression of the coding sequence and the secretion of gene product, (ii) cultivating the recombinant bacterium under or continuous cultivation conditions to express the gene, and (iii) harvesting the recombinant bacterium or the gene product. Preferably, the cultivation medium is a chemically defined or synthetic medium optionally supplemented with yeast extract.
摘要:
A method of identifying nucleotide sequences coding for signal peptides in lactic acid bacteria, using a DNA molecule comprising a transposon including a promoterless reporter gene from which DNA molecule a region between the LR and the reporter gene is deleted and the DNA molecule comprises a DNA sequence coding for a secretion reporter molecule. By deleting the region between the LR and the reporter gene, stop codons in-frame with the secretion reporter molecule is removed which upon transposition permits translational fusions from upstream the LR.
摘要:
Expression vectors capable of being replicated in lactic acid bacterial cells comprising a promoter region comprising (a) a promoter sequence element the function of which is regulatable by an environmental or growth condition factor and (b) at least one further nucleotide sequence element, the position, orientation, presence and/or sequence of which element has a regulatory effect on the expression of a gene operably linked to the promoter region in which vectors the position, orientation, presence and/or sequence of at least one of said elements (a) or (b) is modified relative to the position, orientation, presence and/or sequence of the corresponding non-modified element whereby the expression of the gene is altered, and a lactic acid bacterium which is transformed with such a vector as defined above are provided. The recombinant cells containing such a regulatable or inducible gene expression system are useful as food or feed starter cultures or as strains for the production of gene products such as pharmaceutically or immunologically active compounds including oligo- or polypeptides derived from a Mycobacterium species including M. tuberculosis.