Genomic Insights into Aquimarina sp. Strain EL33, a Bacterial Symbiont of the Gorgonian Coral Eunicella labiata

Abstract

To address the metabolic potential of symbiotic Aquimarina spp., we report here the genome sequence of Aquimarina sp. strain EL33, a bacterium isolated from the gorgonian coral Eunicella labiata. This first-described (to our knowledge) animal-associated Aquimarina genome possesses a sophisticated repertoire of genes involved in drug/antibiotic resistance and biosynthesis.

Comparative genomics reveals complex natural product biosynthesis capacities and carbon metabolism across host‐associated and free‐living Aquimarina (Bacteroidetes, Flavobacteriaceae) species

“…With exception of Aquimarina sp. Aq107, closely related to A. latercula and A. versatilis , all Aquimarina strains retrieved from marine invertebrates (sponges and corals) in the Northeast Atlantic (Esteves et al ., ; Keller‐Costa et al ., , ) affiliated with the A. atlantica ‐ megaterium ‐ macrocephali 16S rRNA gene clade depicted here, which also included several strains retrieved from seawater (Supporting Information Fig. S1).…”

“…Of these genomes, five belong to an in‐house collection of symbionts of octocorals and marine sponges: Aquimarina sp. EL33, Aq78, Aq107, Aq135 and Aq349 (Esteves et al ., ; Keller‐Costa et al ., , ) and the remainder originate from seawater, marine sediments and algae (Table ). Strain Aq349 is the source of the recently described trans ‐AT polyketide cuniculene (Helfrich et al ., ).…”

“…This finding indicated possible cytotoxic capacities for an otherwise unsuspected bacterial taxon given its placement in the Bacteroidetes phylum, most renowned for its role in carbon cycling and whose genomes had been considered to present low numbers of PKS and non‐ribosomal peptide synthetase (NRPS)‐encoding genes (Donadio et al ., ). In recent years, the presence of such genes is being consistently detected in different Aquimarina strains via genome sequencing (Keller‐Costa et al ., ; Ranson et al ., ; Hudson et al ., ). Moreover, structure elucidation of cuniculene, the first trans ‐AT polyketide ever reported from Aquimarina , has just been achieved (Helfrich et al ., ).…”

Host-microbe interactions in octocoral holobionts - recent advances and perspectives

“… Unknown –Zooxanthellate corals: coral– Symbiodinium symbiosis [ 20 , 82 , 93 , 94 , 121 ] Bacteroidetes Flavobacteriia Flavobacteriales Flavobacteriaceae Aquimarina Antillogorgia elisabethae Eunicella spp. Leptogorgia sarmentosa Nutrient cycling Nitrogen cycling (denitrification) Carbon cycling (chitin degradation) Sulfur cycling (sulphate reduction) Microbiome regulation [ 20 , 89 , 101 ] Chlamydiae Chlamydiae Chlamydiales Simkaniaceae Candidatus Fritschea Eunicella spp. Leptogorgia sarmentosa Unknown [ 20 , 76 ] Parcubacteria – – – – Corallium rubrum Unknown [ 20 , 83 ] Proteobacteria Alphaproteobacteria Rickettsiales Rickettsiales incertae sedis Candidatus Lariskella Eunicella spp.…”

“…Another genus specialized for survival in oligotrophic conditions and commonly associated with a tropical [ 89 ] and various temperate gorgonians [ 20 ] is Aquimarina . Genome analysis of an Aquimarina symbiont isolated from Eunicella labiata [ 101 ] has revealed that it possesses a remarkable capacity to cycle nutrients: nitrogen (denitrification), sulfur (assimilatory sulphate reduction), and carbon (chitin degradation). In addition, it has a large arsenal of genes related to defense as well as for the production of antimicrobial compounds.…”