Gut microbiota of bats: pro-mutagenic properties and possible frontiers in preventing emerging disease

Abstract

Bats are potential natural reservoirs for emerging viruses, causing deadly human diseases, such as COVID-19, MERS, SARS, Nipah, Hendra, and Ebola infections. The fundamental mechanisms by which bats are considered "living bioreactors" for emerging viruses are not fully understood. Some studies suggest that tolerance to viruses is linked to suppressing antiviral immune and inflammatory responses due to DNA damage by energy generated to fly. Our study reveals that bats' gut bacteria could also be involved in the host and its microbiota's DNA damage. We performed screening of lactic acid bacteria and bacilli isolated from bats' feces for mutagenic and oxidative activity by lux-biosensors. The pro-mutagenic activity was determined when expression of recA increased with the appearance of double-strand breaks in the cell DNA, while an increase of katG expression in the presence of hydroxyl radicals indicated antioxidant activity. We identified that most of the isolated bacteria have pro-mutagenic and antioxidant properties at the same time. This study reveals new insights into bat gut microbiota's potential involvement in antiviral response and opens new frontiers in preventing emerging diseases originating from bats.

Figure 1

Pro-mutagenic and DNA-protective activity of bats guts lactic acid bacteria and bacilli measured with the E. coli RecA-biosensor. The activity was measured relative to dioxidine. The barplot legend represents groups of isolates identified by mass spectrometry.

Figure 2

Prooxidant and antioxidant activity of bats guts lactic acid bacteria and bacilli measured with the E. coli Kat-biosensor. The activity was measured relative to peroxide. The barplot legend represents groups of isolates identified by mass spectrometry and isolated from individual animals.

Figure 3

Results of the comparison of median values of mutagenic and antioxidant activity of lactobacilli and spore-forming bacilli isolates between different bat species by the Kruskal–Wallace test.

Figure 4

Results of the comparison of median values of mutagenic and antioxidant activity of lactobacilli and spore-forming bacilli isolates from bats of different regions by the Kruskal–Wallace test.

Figure 5

Mosaic plot representing the presence of the combination of pro-mutagenic or DNA-protective and pro- or antioxidant properties of bacteria isolated from bats feces.