A new system for the synthesis of high levels of HBsAg sequence in Escherichia coli.

Using a system to study promoter activity, we have obtained a promoter fragment from E. coli chromosomal DNA. The HBsAg gene under the control of this promoter could be expressed in E. coli. The expression products are isolated and purified by means of a column of anti-HBs cross-linked to Sepharose 4 B. The pure products are characterized through the double diffusion method on 0.6% agarose and polyacrylamide-SDS gel electrophoresis. The synthesis of high levels of HBsAg sequences in E. coli is confirmed.