Abstract: The present invention relates to a composition, comprising: i) an HBcAg1-x, wherein x is a whole number from the range from 100 to 160, a fragment of this antigen, a variant of this antigen or of the fragment of this antigen or at least two thereof, ii) an adjuvant comprising a saponin or a saponin derivative or a mixture of at least two thereof, and optionally iii) an HBsAg, a fragment from this antigen, a variant of this antigen or of the fragment of this antigen or at least two thereof.

Abstract: The invention relates to DNA-molecules comprising DNA-sequences encoding control regions and the structural gene for a protein having formate dehydrogenase (FMDH) activity. Said DNA-molecules may be combined with DNA-sequences encoding foreign genes so as to bring these genes under the stringent control of the regulation of the FMDH regulatory sequences and/or may be combined to DNA-sequences coding for secretory signals. The invention further relates to recombinant vectors containing said DNA-molecules and micro-organisms containing said vectors or DNA-molecules. Furthermore, the invention relates to a process for producing a useful substance by producing this substance by culturing said micro-organisms and recovering the substance.