Updated: Sep 16
Schwarz, M.; Tokuda, G.; Osaki, H.; Mikaelyan, A. Reevaluating Symbiotic Digestion in Cockroaches: Unveiling the Hindgut’s Contribution to Digestion in Wood-Feeding Panesthiinae (Blaberidae). Insects 2023, 14, 768.
Cockroaches in the subfamily Panesthiinae have long been known for their unique ability to feed on wood, much like termites and passalid beetles (Read about our recent work with these guys here: https://lnkd.in/gUkUQb79). However, the prevailing belief was that these cockroaches primarily relied on their own enzymes for lignocellulose digestion, unlike termites and passalid beetles with their well-studied symbiotic digestion systems.
Led by Melbert Schwarz, our study reevaluates this age-old dogma and urges us to rethink the role of symbionts in wood digestion by panesthiine cockroaches. Collaborating with Haruka Osaki and Gaku Tokuda (University of the Ryukyus), who supervised Melbert's work in Okinawa, we embarked on this research funded by several organizations, importantly the Tropical Biosphere Research Center at the University of the Ryukyus that funded Melbert's Japan trip 🗾
Wood is notoriously challenging to digest due to its recalcitrance and low nitrogen content, but certain insects have evolved remarkable adaptations. Termites, for instance, have a complex symbiotic digestion mechanism combining insect-produced enzymes with those from their gut microbiome. Recent studies even suggest passalid beetles employ a similar approach.
However, panesthiine cockroaches seemed to deviate from this pattern. Early research suggested their digestion primarily occurred in the foregut and midgut regions, with minimal contribution from the hindgut. Yet, this might have overlooked the role of "hidden" cell-associated enzymes produced by hindgut bacteria. 🧐
Our study delves deep into the enzyme activity associated with cellulose and xylan breakdown in different gut compartments of Panesthia angustipennis and Salganea taiwanensis. By investigating cellulase and xylanase activity in the crop, midgut, and hindgut, we aim to uncover the potential contribution of hindgut bacteria to wood digestion in panesthiine cockroaches. 🌲🔬
This research opens new doors to understanding the remarkable adaptations of wood-feeding insects and the diversity of mechanisms they employ. Stay tuned for more exciting developments as we continue to unravel the secrets of lignocellulose digestion! 🌳