<p><b>WASHINGTON, DC &ndash; July 23, 2013 -- </b>A benign crystal protein,  produced naturally by bacteria and used as an organic pesticide, could  be a safe, inexpensive treatment for parasitic worms in humans and  provide effective relief to over a billion people around the world.  Researchers from the University of California, San Diego, La Jolla, CA,  report on this potentially promising solution in a study published ahead  of print in the journal <i>Applied and Environmental Microbiology.</i></p>
<p>Hookworms, and other intestinal parasites known as helminths infect  more than 1 billion people in poverty-stricken, tropical nations,  sucking the vitality from the body, and leaving hundreds of millions of  children physically and mentally stunted. Current drugs are  insufficiently effective, and resistance is rising, but little effort  has been made to develop better drugs because the relevant populations  do not represent a profitable market for drug companies.</p>
<p>&ldquo;The challenge is that any cure must be <i>very</i> cheap, it must  have the ability to be mass produced in tremendous quantities, safe, and  able to withstand rough conditions, including lack of refrigeration,  extreme heat, and remote locations,&rdquo; says Raffi Aroian, a researcher on  the study.</p>
<p>In earlier research, Aroian and his collaborators described a  protein, Cry5B, that can kill intestinal nematode parasites&mdash;such as  human hookworms&mdash;in infected test animals (hamsters). Cry5B belongs to a  family of proteins that are generally accepted as safe for humans. These  proteins are produced naturally in <i>Bacillus thuringiensis</i> (Bt), a  bacterium which is applied to crops as a natural insecticide on some  organic farms, and CryB proteins have been engineered into food crops  such as corn and rice, to render them pest resistant.</p>
<p>As shown for the first time in this paper, Cry5B can also be expressed in a species of bacterium, <i>Bacillus subtilis</i>, which is closely related to <i>Bacillus thuringiensis</i>,  and which is also related to bacteria which are present in some  probiotics, says Aroian. In the current research researchers showed that  a small dose of Cry5B, expressed in this bacterium can achieve a 93  percent elimination of hookworm parasites from infected hamsters. That,  says Aroian, is substantially better than current drugs.</p>
<p>The scientific significance of the research, he says, is that  &ldquo;bacteria similar to those that are food grade&mdash;which are cheap and can  readily be mass produced--can be engineered to produce molecules that  can cure parasitic diseases.&rdquo;</p>
<p>Aroian notes that both the Bill and Melinda Gates Foundation, and the  American taxpayer, via the National Institutes of Health, played an  essential role in funding the research.</p>
<p>A copy of the manuscript can be found online at <a href="http://bit.ly/asmtip0713a">http://bit.ly/asmtip0713a</a>.&nbsp;&nbsp;The paper is scheduled to be formally published in the September, 2013 issue of <i>Applied and Environmental Microbiology.</i></p>