The discovery of Bombali virus adds further support for bats as hosts of ebolaviruses

Abstract

Here we describe the complete genome of a new ebolavirus, Bombali virus (BOMV) detected in free-tailed bats in Sierra Leone (little free-tailed (Chaerephon pumilus) and Angolan free-tailed (Mops condylurus)). The bats were found roosting inside houses, indicating the potential for human transmission. We show that the viral glycoprotein can mediate entry into human cells. However, further studies are required to investigate whether exposure has actually occurred or if BOMV is pathogenic in humans.

Figure 1.

Phylogenetic tree comparing the relationship of BOMV to other known filoviruses. Each protein presented separately (i-vii) and as a complete genome (viii). Genbank accession numbers for reference sequences included in Supplemental Data.

Figure 2.

BOMV GP-mediated entry and infection is NPC1-dependent. (A) BOMV GP_1,2 is incorporated in the rVSV particles detected by immunoblotting using ebolavirus anti-GP₁ (B) Infectivity of rVSVs bearing BOMV, EBOV or VSV GP1 on WT or NPC1-KO U2OS cells complemented with or without human NPC1 cDNA. (C) GP₁ alignment of the known human- infecting ebolaviruses (EBOV, SUDV, RESTV, BDBV, TAFV) and BOMV. Displayed regions pertain to the GP₁ interface based on the GP₁-human NPC1 crystal structure (PDB: 5F1B). Conserved residues in blue; viral-specific residues in yellow. Squared positions correspond to residues whose side chain heavy atoms are within 5 Â of any heavy atom in the human NPC1 receptor. (D) Left panel: Atomic representation of the interaction between the human NPC1 (red) and the EBOV GPi protein (blue) (PDB: 5F1B). Middle panel: Close-up view of the interface. Right panel: Close-up view of the modeled interface between the human NPC1 crystal structure (red) and the BOMV GP₁ atomic model (blue). Displayed viral residues (in yellow) correspond to interfacial positions with different amino acids in the BOMV GP₁ protein. Displayed residues on the human NPC1 (in white) correspond to residues with side chain heavy atoms within 5 Å of residues 146 and/or 148 in the EBOV or BOMV GP₁.