From Science Daily:
Intestinal nematodes and roundworms infect more than one billion people worldwide. These parasites lead to malnutrition and developmental problems, especially in children. Unfortunately, resistance to the existing drug treatment is increasing. Now a team of researchers has successfully inserted the gene for a naturally-occurring, insecticidal protein called Bt into a harmless bacterium. This could then be incorporated into dairy products, or used as a probiotic to deliver the protein to the intestines of people afflicted with roundworms.
The research is published in Applied and Environmental Microbiology, a journal of the American Society for Microbiology.
The Bt crystal protein is used in organic insecticidal sprays and has been produced in genetically modified plants as a safe pesticide to kill insects that eat those plants. Bt can also kill some nematodes. In the study, the investigators used the gene for one type of the insecticidal protein, which is naturally produced by the soil bacterium, Bacillus thuringiensis.
The investigators spliced the gene into a plasmid, a short, circular piece of DNA which can replicate independently of the genome in most bacteria. The investigators then inserted the plasmid into Lactococcus lactis, a bacterium that ferments milk to produce yogurt, cheese, and buttermilk. L. lactis was also the first genetically modified organism to be used to treat human disease.
An important property of this bacterium has to do with an odd discovery these researchers made nearly 15 years ago. Normally, molecules of substantial size can only escape from a cell either if cellular machinery in…