Publikationsrepositorium - Helmholtz-Zentrum Dresden-Rossendorf

Generally, heavy metal contamination of the environment is a result of either natural events like volcanic emissions or human activities such as mining processes. High concentrations of heavy metals are toxic to the majority of organisms. However, several bacteria exhibit surprising strategies to survive in metalliferous environments. These strategies are attractive for novel bio-based resource technologies. Their understanding is the purpose of our research.
Aim of this study was the identification of bacterial methods to accept heavy metals in their environment. Genes that are related to the bacterial heavy metal tolerance strategy were analysed.
Lysinibacillus sphaericus JG-B53, an isolate from the uranium mining waste pile Haberland, was studied using genome sequencing analyses in order to identify strain intrinsic survival strategies like surface (S) layer proteins with metal specific binding affinities and metal specific transporter proteins. The genome of Lysinibacillus sphaericus JG-B53 was sequenced using the Next Generation Sequencing Technology. Bioinformatic analyses of generated data were performed with the Genomics Workbench (CLCbio). The expression of selected genes was studied using mRNA methods. Genes and encoded proteins were characterised with special analysing tools.
The genome of Lysinibacillus sphaericus JG-B53 encodes at least 13 S-layer like proteins and 3 metal ion exporter protein genes for metals that occur in the natural habitat. Their characteristics were analysed with multiple gene and protein analysing programs. Using cDNA analyses the expression of 6 putative S-layer proteins was detected.
Future studies will analyse recombinant S-layer proteins regarding their lattice symmetry and metal binding affinities.