A catalog of proteins released from <i>Asaia bogorensis</i> under two growth conditions

Bacterial secretion systems are essential for growth and responsible for a plethora of functions, ranging from nutrient acquisition to biofilm formation and pathogenesis. Bacteria use type II secretion systems (T2SSs) to transport folded proteins from the periplasm outside of the cell in a two-step process. Opportunistic pathogens often secrete virulence factors through this pathway. Type I secretion systems transport proteins across the inner and outer membranes in a single step. The type IV secretion system also transports substrates across the entire cell envelope. It may also translocate substrates directly into target cells. Researchers have utilized the gram-negative bacterium <i>Asaia bogorensis</i> for paratransgenesis. The bacterium was engineered to secrete anti-<i>Plasmodium</i> effector peptides to target the <i>Plasmodium</i> parasites that cause malaria in the mosquito vector through the T2SS. Here, we identify a catalog of proteins released by <i>A. bogorensis</i> under two growth conditions, as well as predictions for the secretion systems that transport them, using liquid chromatography with tandem mass spectrometry. We identified 343 proteins from both growth conditions, with 32 uniquely identified on chocolate agar and 82 proteins from minimal media only. The substrates secreted by the systems identified here may be utilized in the future to improve paratransgenesis. We propose utilizing the type I and/or type IV secretion systems for more streamlined effector secretion directly out of the bacterium, which may improve strain fitness. Fusion of anti-parasitic effector peptides to the substrates encoded at these loci could also serve as an effective minimal paratransgenic strain not reliant upon plasmids.IMPORTANCEBacterial secretion systems are responsible for nutrient acquisition, biofilm formation, and pathogenesis. <i>Asaia bogorensis</i> is a gram-negative bacterium used for paratransgenesis. The bacterium was engineered to secrete anti-<i>Plasmodium</i> effectors to prevent development of the <i>Plasmodium</i> parasites that cause malaria in the mosquito vector. Here, we identify a catalog of proteins released by <i>A. bogorensis</i> under two growth conditions as well as predictions for the secretion systems that transport them. These secretion systems may be used in the future to improve paratransgenesis. We propose utilizing single-step secretion systems for more streamlined effector secretion from the bacterium. Fusion of anti-parasitic effector peptides to the substrates encoded at these loci could serve as an effective minimal paratransgenic strain not reliant upon plasmids. Improvement of secretion by paratransgenic bacteria would allow for more effective interference with <i>Plasmodium</i> parasites in their mosquito vectors. More effective paratransgenesis has the potential to prevent cases of malaria worldwide.