Genomics for biotechnology

A wealth of information has been gained from completely sequenced genomes. So far, most of the sequenced genomes are bacterial genomes. In addition to the basic metabolic pathways, various bacterial genomes encode pathogenici ty, degradation of xenobiotics, synthesis of unusual compounds, or photosyn thesis. The knowledge of the complete DNA sequence of bacterial genomes can facilitate considerably studies of these features as well as their practic al applications in biotechnology. Many open reading frames (ORFs) found in bacterial genomes are identified with their function by a similarity search of standard databases. However, some of the bacterial genome projects are concluded by depositing the nucleotide sequence in a database with no simpl e means to study functions of those ORFs for which a similarity search did not allow convincing functional assignments. It is desirable to develop sys tems for easy functional analysis of these ORFs. Rhodobacter capsulatus is a bacterium that has the potential for developing such systems. Its genome harbors a defective phage called Gene Transfer Agent (GTA) that enables sys tematic deletions of DNA regions of various sizes. This unique feature, tog ether with photosynthesis, nitrogen fixation, degradation of several pollut ants, and synthesis of biodegradable plastic encoded by the R. capsulatus g enome, make this bacterium an attractive subject of biotechnological applic ations.