New insights into a leading poultry disease and its risks to hu...(vian E. coli can carry the same diseas...)

"The best way to prevent this infection is to develop a vaccine," said Mellata. "Our idea is to ultimately protect both poultry and humans by finding a group of genes common against all extra-intestinal E. coli." With this new knowledge of APEC, the group hopes to pursue the development of several new vaccine candidates.

Their latest research results help narrow the genetic search for the cause of APEC infections. Previously, she had shown that a circular, 100,000 base pair long DNA segment, called a plasmid, was responsible for causing disease. Without the plasmid, APEC becomes docile, losing its disease-causing strength.

Plasmids, in an evolutionary game of high-stakes poker, are swapped freely among bacteria in order to gain the upper hand---or in the case of pathogenic E. coli, to outwit its competitors by colonizing animals and causing disease. Over time, each plasmid becomes a patchwork quilt of DNA information, containing DNA parts exchanged among billions of bacterial encounters.

Her team took advantage of the latest advances in DNA sequencing to analyze the complete 103,275 DNA chemical letters that make up the plasmid, called pAPEC-1.

The multidisciplinary effort involved expertise from several ASU researchers, including Jeff Touchman, a School of Life Science Professor specializing in bioinformatics. It also utilized MEGA4, a software program developed by the Biodesign colleague Sudhir Kumar's lab that is used by more than 50,000 scientists worldwide to trace back and compare the evolutionary history of any DNA segment.

"DNA sequencing and bioinformatics analysis are very powerful tools that contribute in fully understanding the virulence of APEC, and provide new avenues of research," said Mellata.

The ABCs of APEC

In all, the group found 31 ge
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