'Candidatus Gromoviella agglomerans', a novel intracellular Holosporaceae parasite of the ciliate Paramecium showing marked genome reduction.
Journal
Environmental microbiology reports
ISSN: 1758-2229
Titre abrégé: Environ Microbiol Rep
Pays: United States
ID NLM: 101499207
Informations de publication
Date de publication:
02 2022
02 2022
Historique:
received:
28
04
2021
accepted:
14
09
2021
pubmed:
13
11
2021
medline:
5
4
2022
entrez:
12
11
2021
Statut:
ppublish
Résumé
Holosporales are an alphaproteobacterial lineage encompassing bacteria obligatorily associated with multiple diverse eukaryotes. For most representatives, little is known on the interactions with their hosts. In this study, we characterized a novel Holosporales symbiont of the ciliate Paramecium polycaryum. This bacterium inhabits the host cytoplasm, frequently forming quite large aggregates. Possibly due to such aggregates, host cells sometimes displayed lethal division defects. The symbiont was also able to experimentally stably infect another Paramecium polycaryum strain. The bacterium is phylogenetically related with symbionts of other ciliates and diplonemids, forming a putatively fast-evolving clade within the family Holosporaceae. Similarly to many close relatives, it presents a very small genome (<600 kbp), and, accordingly, a limited predicted metabolism, implying a heavy dependence on Paramecium, thanks also to some specialized membrane transporters. Characterized features, including the presence of specific secretion systems, are overall suggestive of a mild parasitic effect on the host. From an evolutionary perspective, a potential ancestral trend towards pronounced genome reduction and possibly linked to parasitism could be inferred, at least among fast-evolving Holosporaceae, with some lineage-specific traits. Interestingly, similar convergent features could be observed in other host-associated lineages, in particular Rickettsiales among Alphaproteobacteria.
Identifiants
pubmed: 34766443
doi: 10.1111/1758-2229.13021
doi:
Substances chimiques
RNA, Ribosomal, 16S
0
Types de publication
Journal Article
Research Support, Non-U.S. Gov't
Langues
eng
Sous-ensembles de citation
IM
Pagination
34-49Informations de copyright
© 2021 Society for Applied Microbiology and John Wiley & Sons Ltd.
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