Biomineralization is a naturally occurred process, by which microorganism reduced mental ions to minerals. Bacteria-driven biomineralization is most applied in metal recycling or environmental governance, the biomineralized products are rarely used. This probably due to the attachments of microorganism derived components on minerals, such as proteins, which are treated as impurities and hard to remove. However, these microorganism generated molecules are potent in activation of immune systems, suggesting promising potentials of biomineralized products in developing immunotherapeutic strategies. In this research, we analyzed the protein components on DH5a Escherichia coli produced gold nanoparticles, to explored the generation process of gold nanoparticles in bacterial cells, as well as its immune adjuvant potentials.