Introduced ascidians harbor highly diverse and host-specific symbiotic microbial assemblages

James S. Evans, Patrick M. Erwin, Noa Shenkar, Susanna López-Legentil*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review


Many ascidian species have experienced worldwide introductions, exhibiting remarkable success in crossing geographic borders and adapting to local environmental conditions. To investigate the potential role of microbial symbionts in these introductions, we examined the microbial communities of three ascidian species common in North Carolina harbors. Replicate samples of the globally introduced species Distaplia bermudensis, Polyandrocarpa anguinea, and P. zorritensis (n = 5), and ambient seawater (n = 4), were collected in Wrightsville Beach, NC. Microbial communities were characterized by next-generation (Illumina) sequencing of partial (V4) 16S rRNA gene sequences. Ascidians hosted diverse symbiont communities, consisting of 5,696 unique microbial OTUs (at 97% sequenced identity) from 47 bacterial and three archaeal phyla. Permutational multivariate analyses of variance revealed clear differentiation of ascidian symbionts compared to seawater bacterioplankton, and distinct microbial communities inhabiting each ascidian species. 103 universal core OTUs (present in all ascidian replicates) were identified, including taxa previously described in marine invertebrate microbiomes with possible links to ammonia-oxidization, denitrification, pathogenesis, and heavy-metal processing. These results suggest ascidian microbial symbionts exhibit a high degree of host-specificity, forming intimate associations that may contribute to host adaptation to new environments via expanded tolerance thresholds and enhanced holobiont function.

Original languageEnglish
Article number11033
JournalScientific Reports
Issue number1
StatePublished - 1 Dec 2017


FundersFunder number
United States-Israel Binational Science Foundation2014025


    Dive into the research topics of 'Introduced ascidians harbor highly diverse and host-specific symbiotic microbial assemblages'. Together they form a unique fingerprint.

    Cite this