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Abstract Heritable symbionts are common in terrestrial arthropods and often provide beneficial services to hosts. Unlike obligate, nutritional symbionts that largely persist under strict host control within specialized host cells, heritable facultative symbionts exhibit large variation in within-host lifestyles and services rendered with many retaining the capacity to transition among roles. One enigmatic symbiont, Candidatus Fukatsuia symbiotica, frequently infects aphids with reported roles ranging from pathogen, defensive symbiont, mutualism exploiter and nutritional co-obligate symbiont. Here we used an in vitro culture-assisted protocol to sequence the genome of a facultative strain of Fukatsuia from pea aphids (Acyrthosiphon pisum). Phylogenetic and genomic comparisons indicate that Fukatsuia is an aerobic heterotroph, which together with Regiella insecticola and Hamiltonella defensa form a clade of heritable facultative symbionts within the Yersiniaceae (Enterobacteriales). These three heritable facultative symbionts largely share overlapping inventories of genes associated with housekeeping functions, metabolism, and nutrient acquisition, while varying in complements of mobile DNA. One unusual feature of Fukatsuia is its strong tendency to occur as a co-infection with H. defensa. However, the overall similarity of gene inventories among aphid heritable facultative symbionts suggest that metabolic complementarity is not the basis for co-infection, unless playing out on a H. defensa strain-specific basis. We also compared the pea aphid Fukatsuia with a strain from the aphid Cinara confinis (Lachninae) where it is reported to have transitioned to co-obligate status to support decaying Buchnera function. Overall the two genomes are very similar with no clear genomic signatures consistent with such a transition, which suggests co-obligate status in C. confinis was a recent event.
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Genome Sequences of Five Type Strain Members of the Archaeal Family Sulfolobaceae, Acidianus ambivalens, Acidianus infernus, Stygiolobus azoricus, Sulfuracidifex metallicus, and Sulfurisphaera ohwakuensis
ABSTRACT Presented are five genomes from the polyextremophilic (optimal temperature of >65°C and optimal pH of <3.5) archaeal family Sulfolobaceae , greatly expanding order-wide genomic diversity. Included are the only obligate anaerobic species, several facultative sulfur utilizers, two metal mobilizers, one facultative chemolithoautotroph with robust metabolic versatility, and some of the most thermophilic thermoacidophiles reported to date.
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- Award ID(s):
- 1802939
- PAR ID:
- 10162284
- Date Published:
- Journal Name:
- Microbiology Resource Announcements
- Volume:
- 9
- Issue:
- 11
- ISSN:
- 2576-098X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1128/MRA.01490-19
