Symbionts of stored-grain beetle pests

Several beetles of the families Anobiidae, Bostrychidae and Silvanidae are economically important pests of stored products, incl. Grain, dried fruits and wood. Interestingly, many of them are associated with microbial symbionts that enable them to thrive under these hash conditions. The Bostrychid and Silvanid beetles are associated with closely related Bacteroidetes bacteria that are harbored in specialized organs and synthesize products of the Shikimate pathway. These constitute essential components for the synthesis of their cuticle. The Anobiid beetles on the other hand harbor yeasts in the epithelial tissue of several gut appendages. The two important pest species, the cigarette and the drugstore beetle, are associated with yeasts of the genus Symbiotaphrina that supply various nutrients and were described to be involved in the breakdown of toxic plant metabolites. Using manipulative experimentation as well as whole genome sequencing, we aim to elucidate the evolutionary history of the symbiosis, the functional role of the beetle endosymbionts, and their potential as a target for biological control of the beetles.

Tobias Engl, Junbeom Lee, Julian Kiefer, Nomthi Khanyile, Jürgen Wierz

Selected publications:

Engl, T., Eberl, N., Gorse, C., Krüger, T., Schmidt, T.H., Plarre, R., Adler, C. & Kaltenpoth, M. (2018) Ancient symbiosis confers desiccation resistance to stored grain pest beetles. Molecular Ecology 27 (8): 2095-2108.