A Stage in the Age of the Phage
Gina Kolata of the NYTimes has an interesting article up today discussing the German E. coli O104:H4 outbreak. It turns out that a combination of two factors, the ability of the bug to produce Shiga toxin and to form a solid and tightly adhering biofilm on the walls of the intestines, is responsible for the severity of the illnesses suffered. It also appears that contrary to original assumptions the bacteria came not from food animals but from people.
How though did E. coli O104:H4 come to acquire the ability to produce Shiga toxin? We know it's produced by E. coli O157:H7 but how did this other bug come to produce a variant of the poison? Enter the phage.
E. coli O104:H4 doesn't have genes that would allow it to make Shiga toxin and guess what? Neither does E. coli O157:H7. Instead, they come from a phage that has infected E coli. and turned it into a deadly pathogen. See "Phage on the Rampage" in Nature News.
So bacteriophages are the villains of the E. coli story, right? Well, yes, and no. It depends on the phage. Clever bioengineers have found another phage that rips E. coli O157H7 apart and they've fed it to cows. The therapy reduces the level of E. coli O157:H7 in cows and thereby reduces the risk of infection to humans. See e.g. "Application of Bacteriophages To Control Intestinal Escherichia coli O157:H7 Levels in Ruminants" and "Oral and Rectal Administration of Bacteriophages for Control of Escherichia coli O157:H7 in Feedlot Cattle."
Phage therapy isn't just for cows. Though it's been around for decades it was largely ignored in the West and its full potential never unlocked behind the iron curtain. Now, "bacteriophage-based 'probiotic products' may provide a novel, safe and effective approach for favorably manipulating the GI tract's microflora".
A cup of live bacteria chased with a spoonful of phages - together sent into your gut daily to wage war against our ancient enemies. What a world. And because it's so far beyond the future world we imagined we can be certain that at least some of the adventures on which we'll embark will end badly. And that means mass torts will be around for the biological revolution just as it was for the industrial version.
