A Genetically Modified Anti-Plasmodium Bacterium Is Harmless to the Foragers of the Stingless Bee Partamona helleri

Abstract

Paratransgenesis consists of genetically engineering an insect symbiont to control vector-borne diseases. Biosafety assessments are a prerequisite for the use of genetically modi ed organisms (GMOs). Assessments rely on the measurement of the possible impacts of GMOs on different organisms, including bene cial organisms, such as pollinators. The bacterium Serratia AS1 has been genetically modi ed to express anti-Plasmodium effector proteins and does not impose a tness cost on mosquitoes that carry it. In the present study, we assessed the impact of this bacterium on the native bee Partamona helleri (Meliponini), an ecologically important species in Brazil. Serratia eGFP AS1 (recombinant strain) or a wild strain of Serratia marcescens were suspended in a sucrose solution and fed to bees, followed by measurements of survival, feeding rate, and behavior (walking and ying). These bacteria did not change any of the variables measured at 24, 72, and 144 h after ingestion. Recombinant and wild bacteria were detected in the digestive tract up to 144 h after ingestion, but their numbers decreased with time. The recombinant strain was detected in the midgut at 24 h and in the hindgut at 72 h and 144 h after ingestion. As reported for mosquitoes, Serratia eGFP AS1 is a safe candidate for combating vector-borne diseases, as it did not compromise the native and ecologically relevant bee, P. helleri.

Survivorship and food consumption of immatures and adults of Apis mellifera and Scaptotrigona bipunctata exposed to genetically modified eucalyptus pollen

“…In the tropics, a wide diversity of social bees defined as stingless bees exist (Apidae: Meliponini) (Sakagami 1982). Recently, several species of stingless bees have been included in risk assessments of pesticides and other potential compounds like GMOs (Lima et al 2013;Barbosa et al 2015;dos Santos et al 2016;Bernardes et al 2018;Seide et al 2018;Dorigo et al 2019;Dorneles et al 2021;Viana et al 2022). The risk assessments with stingless bees is slightly distinctive from the one conducted with A. mellifera.…”