Comunidades bacterianas associadas a colônias de abelhas amazônicas sem ferrão da espécie Melipona seminigra: diversidade e potencial enzimático

Abstract

Bees, as other social insects, present complex symbiotic interactions with microorganisms, ranging from the individual level (bee) to the different microenvironments of the nest/ colony. These relationships can directly affect the nutritional potential and immunity of bees as well as influence productive processes within the colony, such as food storage and production. Considering that: i) there are few studies on the microbiota of wild bees, in constrast with the available literature of exotic bees Apis mellifera; ii) the knowledge about the symbiotic microorganisms contribute to the understanding of the ecological relationship that guarantee the colony homeostasis and it also provides tools for the prospection of products of biotechnological interest; iii) the fermentative production of bee pollen, the main food of the colony, is a little known process regardless its fundamental importance to the social colonies development; the objective of this work was to elucidate the bacterial communities associated with the bee gut and food supplies based on pollen of the Amazonian bee Melipona seminigra, with the purpose of knowing better the microorganisms associated to this bee and the process of storage and preservation of the bee pollen in the colony, glimpsing biotechnological applications. The experiments were carried out in three phases, starting with the description of the bacterial microbiota present in the pollen supply of Melipona seminigra bee, using independent culture methods (direct sequencing of microbial DNA samples) and culture-dependent methods ( Bacterial culture). Bacterial isolates obtained by pollen and larval food cultivation were evaluated for their hydrolytic enzyme production. Finally, the study of the Melipona seminigra gut microbiota was carried out based on cloning and sequencing of the 16SrRNA gene. It was identified 26 bacterial genera associated to pollen provisions of Melipona seminigra, many of which are of environmental in origin and related to natural and / or industrial fermentation processes. Changes in the bacterial composition of pollen from its collection until maturation suggest that the production of this food is mediated by a microbial succession process. Most of the bacteria isolated from pollen produce lipases, amylases, proteases and cellulases with high enzymatic indexes, indicating the potential of them for the bioprospection of enzymes of industrial interest. Regarding to the gut microbiota it was demonstrated that the bacterial populations colonize differentially the morphofunctional parts of gut, being the greater diversity of bacteria found in the middle and posterior intestines. This work resulted in unprecedented data on M. seminigra microbiota, which largely contribute to a better understanding of the complex and fascinating symbiotic relationships between social bees and microorganisms.