Tsaitermes ampliceps (lower termites) and Mironasutitermes shangchengensis (higher termites) are highly eusocial insects that thrive on recalcitrant lignocellulosic diets through nutritional symbioses with gut dwelling prokaryotes and eukaryotes. We used denaturing gradient gel electrophoresis and a 16S rRNA clone library to investigate i) how microbial communities adapt to lignocellulosic diets with different cellulose and lignin content, ii) the differences in the dominant gut microbial communities of the 2 types of termites.
Denaturing gradient gel electrophoresis
We investigated the biodegradability of oil in mangrove sediment from Camamu Bay and measured its effect on the bacterial community. Microcosms of mangrove sediment were contaminated with 0.1, 0.5, 1, 2, and 5% (w/v) oil, and the microbial activity was compared to that in uncontaminated sediment. The evolution of CO2 and gas chromatography showed the mineralization of oil compounds, which could reach 100%. Bacterial diversity was determined by polymerase chain reaction using a set of primers for the V3 and V6-V8 regions of 16S rDNA.
Locusts are able to digest the cellulose of Gramineae plants, resulting in their being considered as major crop pests. To illustrate the mechanism involved in cellulose digestion, the cellulolytic activity and zymography in the gut contents of 16 locust species were determined using carboxymethyl cellulose (CMC) as substrate. The diversity of gut symbiotic bacteria was studied using denaturing gradient gel electrophoresis (DGGE). The results showed that high CMC activity was present in Acrididae gut fluid (mean 356.4 U/g proteins).