NEW INTERGENIC AND INTRAGENIC INTEGRATION SITES FOR FOREIGN GENE EXPRESSION IN RECOMBINANT S. <i>GORDONII </i> STRAINS
摘要
The present invention provides two new chromosomal integration sites for expression of foreign genes have been developed in <i> Streptococcus gordonii (S. gordonii)</i>. One integration site is intergenic between orfA and orfB in an operon of unknown function. The other site is intragenic within the <i>lacG</i> gene, which encodes phospho- beta -galactosidase, and is part of the lactose (<i>lac</i>) operon. The<i>m6 </i>gene from<i> Streptococcus pyogenes</i> was integrated in a stable configuration into the chromosome of <i> S. gordonii</i> at each of these integration sites, and in both cases the recombinant bacteria expressed the M6 protein on their surface. Furthermore, expression from the lacG site within the lactose operon was shown to be regulated by growth on lactose. Identification of these new chromosomal insertion sites provides the ability to express multiple foreign genes from the same recombinant and the potential for modulating expression <i>in vitro</i> or <i>in vivo</i> by the use of a biosynthetic metabolite.
