Bactérias intestinais em cupins: variação na beta diversidade e o efeito na sobrevivência do hospedeiro

Abstract

The bacterial gut microbiota of termites promotes the regulation of metabolism and efficient digestion and contributes to defensive mutualism, which reflects on host susceptibility. However, factors associated with microbiota modulation include diet and caste. In the present study, we evaluated the influence of feeding habits and caste of termites on gut bacterial diversity in species of the family Termitidae and the survival of Constrictotermes cyphergaster after exposure to the gut Bacillus thuringiensis (Bt). The results showed changes in diversity, with variations in the structure and composition of symbionts, with significant differences between the workers and feeding guilds (Reapers and intermediates) of the species studied. These changes were associated with diet, as well as the functions performed by the castes. Although different, add up to the trophallaxis process that contributes to the sharing of gut symbionts. As for the survival of C. cyphergaster, the results showed that Bt does not seem to affect the survival of this termite, unlike what occurred in individuals exposed to the opportunistic bacterium Pseudomonas aeruginosa (Pa). Factors such as virulence, intestinal condition of the host, and virulence of the bacterial strain may permeate the results found. In addition, the physiological and behavioral change of the individuals was elucidated through lethargy, body and feeding decrease after exposure to the bacterial pathogens. Although factors that alter the gut microbiota are already known, the population dynamics associated with the functional roles played by these symbionts in termites requires multidisciplinary approaches, since it reflects an under-explored field, which may confer insights into the process of coevolution between termites and bacterial pathogens.