Specific Features of Nitrogen Fixation and Denitrification in Termites Neotermes castaneus, Zootermopsis angusticollis, and Reticulitermes lucifugus

We studied specific features of microbial nitrogen fixation and denitrification in laboratory cultures of the termites Neotermes castaneus, Zootermopsis angusticollis, and Reticulitermes lucifugus, as well as in their nest materials. The nitrogenase activity in the termites was much higher than in the materials of termitarium. Denitrification was found only in the nest materials of termitarium. Studies of the bacterial community of gut nitrogen fixers Neotermes castaneus have shown the predominance of anaerobic and facultatively anaerobic bacteria that amount to up to 60% of the total number of gut bacteria. In the materials of termitarium, aerobic cellulose-destroying myxobacteria predominated, which are typical inhabitants of plant substrates, a food for the termites.