In 2019, researchers reported a new family of DNA viruses, Redondoviridae, which are frequently found in human mouth swabs and are particularly abundant in cases of periodontitis and other diseases. Until now, however, it was unknown whether Redondoviridae infects human cells themselves or one of the mouth’s resident eukaryotic microbes; the viruses’ genomic sequences suggested that bacteria were unlikely to be the hosts.
A new study published today (December 1) in Cell Host & Microbe points to the protist Entamoeba gingivalis as a host for these viruses, based on phylogeny, cooccurrence of both organisms in human samples, and culture analyses of the amoeba. These results bolster a computational prediction made independently by another group and published September 16 in Virus Evolution—while the new study was under review—that suggested this eukaryote as the most likely host.
“We wanted to know what cell they grew on,” as the redondoviruses are so abundant ...
