Cameroonian fruit bats harbor divergent viruses, including rotavirus H, bastroviruses, and picobirnaviruses using an alternative genetic code

Yinda, Claude Kwe; Ghogomu, Stephen Mbigha; Conceição-Neto, Nádia; Beller, Leen; Deboutte, Ward; Vanhulle, Emiel; Maes, Piet; Van Ranst, Marc; Matthijnssens, Jelle

Recently, viral genomes with characteristics of both astro-and hepatitis E-like genomes (called bastrovirus) were identified in human stool samples from the Netherlands. Analysis of these genomes revealed they are made up of two ORFs: ORF1 contain non-structural domains that share identity with domains from members of the family Hepeviridae while ORF2 contain structural protein that shares the highest sequence identity with members of the Astroviridae (Oude Munnink et al. 2016). Further, unpublished sequences of bastrovirus and bastro-like viruses have been identified from rats, pigs, and bats from Vietnam. Here we describe a novel bastro-like virus in bats from Cameroon and analysis of the genome showed the same genome organization as those found in humans, rats, and other bats (Fig. 5A) . A phylogeny based on the capsid (Fig. 5B) showed a cluster of human bastrovirus closest to astrovirus and distantly related to HEV strains. Most of the animal bastroviruses form a monophyletic clade except for the two highly divergent strains Bat_Bastrovirus-like_virus/VietNam/Bat/17819_21 and Bat_Bastrovirus/VietNam/Bat/16715_30. Inside this bastrovirus cluster, strains cluster according to their bat, rat or porcine host species, including the Cameroonian (Bat_Bastrovirus/CMR/Bat/ P24) and Vietnamese (Bastrovirus/VietNam/Bat/16715_78) bat bastrovirus strains (77% amino acid similarity). The RdRp phylogenetic tree shows that bastroviruses and hepatitis E viruses form a unique clade, distinct from astroviruses (Fig. 5C ). All bastroviruses form a monophyletic clade, and again they cluster per host species, including the Cameroonian and Vietnamese bat strains (KX907133 and KX907131, 77% amino acid identity).