Glucose Derivative Takes Down Termites

Something as simple as a modified sugar could help knock out termites and lead to a general nontoxic form of pest control, according to a new report (Proc. Natl. Acad. Sci. USA, DOI: 10.1073/pnas.0904063106). Gram-negative bacteria binding proteins (GNBPs) are receptors in insect immune systems that alert the creatures to the presence of pathogens. Although GNBPs share features with bacterial β-glucanases, which are enzymes that digest glucans, biologists thought that the insect proteins had lost their enzymatic activity. Ram Sasisekharan of MIT, Rebeca B. Rosengaus of Northeastern University, and coworkers discovered that at least one GNBP in termites, GNBP-2, which they found in termite nest material, still has β(1,3)-glucanase activity. The researchers then looked for a small molecule that would block only the β-glucanase activity without hindering other functions. A glucose derivative, D-glucono-δ-lactone (GDL), does the trick. Treating termites with GDL increases the insects' susceptibility to infection by a fungal termite pathogen, leading the researchers to suggest that GDL could be incorporated in building materials as a pest control measure.