Emerging bug pilfers DNA
By Brian Vastag
A bacterium that’s spreading in U.S. hospitals and on the battlefields of the Middle East has filched some of its most dangerous genes from other bacteria, say researchers who sequenced the bug’s genome.
In 2004, the Centers for Disease Control and Prevention reported that 240 U.S. soldiers in the Middle East had suffered antibiotic-resistant bloodborne infections due to Acinetobacter baumannii. Stateside hospitals have also reported a rise in stubborn infections from the bug. According to previous research, it kills up to 75 percent of the people it infects.
Michael Snyder and his colleagues at Yale University sequenced the genome of the more virulent of the two known strains of A. baumannii. Using a new technology called high-density pyrosequencing, the team decoded the genome in a few weeks.
The genome includes 28 stretches of DNA that match sequences found in other organisms. Fully 17 percent of A. baumannii’s genome appears to have been imported, says Snyder, who compares the bug’s genome to a pair of old, patched jeans.
The researchers say that the pilfered DNA gives the bug much of its tenacity and that it includes genes that produce toxic substances and defeat antibiotics.
The research appears in the March 1 Genes & Development.