Genomes of two popular E. coli strains sequenced
By TechnoGadge on October 21, 2009 at 3:42 amA team of researchers from the United States, Korea, and France has sequenced and analyzed the genomes of two important laboratory strains of E. coli bacteria, one used to study evolution and the other to produce proteins for basic research or practical applications.
E. coli Bacteria
E. coli has been associated with recent outbreaks of food-borne illnesses, but the two most important laboratory types, named K-12 and B, were isolated from benign E. coli that are normal inhabitants of the human intestine. Both have been indispensable tools for biomedical research and biotechnology.
K-12 was isolated in 1922 in Palo Alto, California. Its genome sequence – the series of nucleotide bases (labeled A, T, G, and C) that make up the source code for running the machinery of the cell – has been known since 1997. The early history of B, however, was unknown until the current collaboration combed through historical scientific papers and personal recollections to trace it back to a strain at the Institut Pasteur, in Paris, in 1918. Adding to this historical reconstruction, the newly sequenced genomes of two different B strains allow the complete genomes of these laboratory workhorses to be compared for the first time.
The genome comparisons also turned up some interesting differences between the two B strains. Like identical twins separated at birth, the two B strains have had separate laboratory histories since 1959. One became REL606, a strain used by Richard Lenski at Michigan State University and his collaborators to study long-term evolution in the laboratory. The other became BL21(DE3), a strain developed by Studier and colleagues at Brookhaven Lab to be used as a “factory” for producing proteins for basic research and for medical and industrial use.
The findings will help guide future research and will also open a window to a deeper understanding of classical research that is the foundation of our understanding of basic molecular biology and genetics. The team published its results online on October 17, 2009, in three papers in the Journal of Molecular Biology.
Source: Brookhaven National Laboratory (http://www.bnl.gov/)
Category: Science | Tags: Bacteria, E. coli, Research, Science