A novel surface layer protein of the uranium waste pile isolate Bacillus sphaericus JG-A 12 and its interaction with metals

Bacteria in uranium waste piles are of special interest for bioremediation, because they are adapted to high concentrations of heavy metals in these environments. One bacterial isolate from a uranium mining waste pile "Haberland" near the town of Johanngeorgenstadt in Saxony, Germany, Bacillus sphaericus JG-A 12, possesses a surface layer (S-layer) protein which differs significantly from the other S-layers studied up to date. Interestingly, the N-terminal domain (182 amino acid residues) of this S-layer is almost identical to that of B. sphaericus NCTC 9602 which was also analyzed in our laboratory. Vegetative cells and spores of the two B. sphaericus strains accumulate selectively large amounts of U, Pb, Cd, Cu and Al from the highly polluted drain waters of the uranium waste. The interaction of the S-layers of the two strains with U, Pt and Pd were studied in particular, using IR spectroscopy and EXAFS spectroscopy. The ability of the vegetative cells, spores and S-layers of the two B. sphaericus strains to interact with metal ions makes them prospective for bioremediation. Results on entrapping of vegetative cells of B. sphaericus JG-A 12 and B. sphaericus 9602 in SiO2 ceramics using the sol-gel process, will be presented.