Further evidences of an emerging stingless bee-yeast symbiosis

Abstract

Symbiotic interactions between microorganisms and social insects have been described as crucial for the maintenance of these multitrophic systems, as observed for the stingless bee Scaptotrigona depilis and the yeast Zygosaccharomyces sp. SDBC30G1. The larvae of S. depilis ingest fungal filaments of Zygosaccharomyces sp. SDBC30G1 to obtain ergosterol, which is the precursor for the biosynthesis of ecdysteroids that modulate insect metamorphosis. In this work, we find a similar insect-microbe interaction in other species of stingless bees. We analyzed brood cell samples from 19 species of stingless bees collected in Brazil. The osmophilic yeast Zygosaccharomyces spp. was isolated from eight bee species, namely Scaptotrigona bipunctata, S. postica, S. tubiba, Tetragona clavipes, Melipona quadrifasciata, M. fasciculata, M. bicolor, and Partamona helleri. These yeasts form pseudohyphae and also accumulate ergosterol in lipid droplets, similar to the pattern observed for S. depilis. The phylogenetic analyses including various Zygosaccharomyces revealed that strains isolated from the brood cells formed a branch separated from the previously described Zygosaccharomyces species, suggesting that they are new species of this genus and reinforcing the symbiotic interaction with the host insects.

Scaptona ramosa gen. nov., sp. nov., isolated from nest of the stingless bee

“…Studies regarding ecological relationships and fungal species composition in substrates related to native bees are still rare. In Brazil, the relationship between fungi and Scaptotrigona depilis has been investigated [28][29][30]. In addition, other studies have reported the presence of different microorganisms associated with other genera of stingless bees [31,32].…”

Distinct fungal microbiomes of two Thai commercial stingless bee species, Lepidotrigona terminata and Tetragonula pagdeni suggest a possible niche separation in a shared habitat

“…Fall armyworm ( Spodoptera frugiperda ) harbors fungal symbionts such as Fusarium oxysporum and Cladosporium sp ( Watson et al., 2023 ). Like other insects, bees depend on a symbiotic relationship with microbes, ranging from pathogenic to mutually beneficial ( de Paula et al., 2023 ; Rutkowski et al., 2023 ). Common fungal symbionts include yeasts from the taxa of Starmerella , Metschnikowia , Zygosaccharomyces , and Candida , which are found across various tribes and species ( Rutkowski et al., 2023 ).…”

“…postica , Sc. tubiba , Tetragona clavipes , Melipona quadrifasciata , M. fasciculata , M. bicolor , and Partamona helleri ( de Paula et al., 2023 ). Additionally, Liu et al.…”