Team sequences largest bacterial genome to date

Vancouver, BC – An international team led by three UBC microbiologists has completed the sequencing and annotation of the genome of Rhodococcus sp RHA1, a soil bacterium, which is the largest bacterial genome sequenced to date. It is the first genome of a Rhodococcus to be completely sequenced, and the first bacterial genome to be entirely sequenced and annotated in Canada.

"We began this project expecting to learn more about how these bacteria degrade toxic pollutants, but ended up also coming up with ideas on how to cut costs in the production of antibiotics and other important pharmaceuticals," saysDr Lindsay Eltis, who together with Drs William Mohn and Julian Davies spearheaded the research effort.

The sequencing of the organism’s genome has contributed to understanding the physiological basis of its exceptional ability to break down PCBs and other toxic wastes and its adaptation to environmental stresses. According to Dr Mohn, "This genome sequence is a powerful new tool for advancing our understanding of how microorganisms degrade toxic pollutants and how a group of important soil microorganisms function in their natural environment."

Because of their strong catabolic capacities and genetic plasticity, microorganisms such as Rhodococcus sp RHA1 are capable of breaking down complex organic compounds including environmental pollutants. The organism was isolated from soil containing lindane, a highly toxic insecticide, by Dr Masao Fukuda, a collaborator in Japan. "We picked this organism because of its environmental and industrial importance. The most commercially successful application of a bacterium in an industrial process involves a strain of Rhodococcus," adds Dr Eltis.

Another important finding of the research shows just how similar rhodococci are to streptomycetes, a family of bacteria that produce over 70% of the antibiotics in use today. "By making the genome sequence of Rhodococcus RHA1 available to the scientific community worldwide we hope that other research teams will build on this knowledge to develop new antibiotics and other pharmaceutical products," says Dr Michael McLeod, head of annotation in the microbial envirogenomics group at the university.

The sequencing and assembly of the DNA was performed at the Michael Smith Genome Sciences Center (GSC), while the sequence analysis and subsequent experimental research was performed by the MEG. "The sequence is of a very high quality, which means that the international scientific community using the data can do so with a high degree of confidence," said Dr. Eltis.

The sequence and annotation of the Rhodococcus sp. RHA1 genome will be formally presented to the scientific community at the International Conference on Microbial Genomes on April 13-16, 2005 in Halifax, Nova Scotia, Canada. For more information on this research visit the official Rhodococcus Genome Project web site at http://www.rhodococcus.ca/.

The project involves collaborations with researchers from Japan, Germany, England, Spain, Argentina, The Netherlands, Ireland and the United States.