Research

Reproductive Symbiosis of the Hawaiian bobtail squid

Left: Adult female bobtail squid

Upper Right: Bobtail squid eggs

Lower Right: Squid egg bacteria

Our research investigates the molecular mechanisms of defensive symbioses, using the Hawaiian bobtail squid, Euprymna scolopes, as a model. Female squid house a diverse bacterial community in a reproductive gland, known as the accessory nidamental gland (ANG). During egg laying, female squid deposit this bacteria into a jelly layer that surrounds the developing embryo. These bacteria protect the egg from infection over the course of development, but little is known about how they provide this protection. The various projects in our lab examine how squid egg symbionts are able to compete with other microbes, including potential egg pathogens.

Mining bacterial genomes for antimicrobial gene clusters

By sequencing the genomes of squid symbionts, we can use bioinformatic tools to search for genes that may produce antimicrobials. Theses genes can then be mutated to determine their role in bacterial competition. We can also perform comparative genomics to determine if these gene clusters are common to all symbionts or unique to select symbionts.

Testing genes necessary for antimicrobial activity

We use two genetic approaches to mutate symbiont strains: random transposon insertion and targeted gene disruption. By mutating predicted antimicrobial genes in symbionts, we can compete these strains against target microbes in competition assays. If we observe a loss of inhibition compared to non-mutated (wild type) strains, then we can determine which genes are necessary for antimicrobial activity.

In vitro symbiont competition

Symbionts not only compete with non-symbiotic bacteria, but they must also compete with other symbionts for colonization space in their host. We are interested in seeing how squid egg symbionts interact with each other in the shared egg jelly coat environment. We are testing this by experimentally manipulating the egg community via injection of mutant strains.

Publications

*Authors contributed equally

Suria, A.M., S. Smith, L. Speare, Y. Chen, I. Chien, E.G. Clark, M. Kruger, A.M. Warwick, H. Wilkins, A.N. Septer. 2022. Prevalence of Type VI Secretion Systems in a Model Beneficial Symbiosis. Frontiers in Microbiology, DOI: 10.3389/fmicb.2022.988044.

McAnulty, S.J.*, A.H. Kerwin*, E. Koch, B. Nuttall, A.M. Suria, A.J. Collins, T.R. Schleicher, B.A. Rader, S.V. Nyholm. 2022. “Failure to Launch”: Development of a reproductive organ linked to symbiotic bacteria. mBio, DOI: 10.1128/mbio.02131-22.

Suria, A.M.*, K. Tan*, A.H. Kerwin, L. Gitzel, L. Abini-Agbomson, J. Bertenshaw, J. Sewell, M.J. Balunas, and S.V. Nyholm. 2020. Hawaiian bobtail squid symbionts inhibit marine bacteria via production of specialized metabolites, including new bromoalterochromides BAC-D/D'. mSphere, 5:e00166-20. DOI: 10.1128/mSphere.00166-20.

Kerwin, A.H.*, S. Gromek*, A.M. Suria, R.M. Samples, D.J. Deoss, K. O’Donnell, S. Frasca Jr., D.A. Sutton, N.P. Wiederhold, M.J., Balunas, and S.V. Nyholm. 2019. Shielding the next generation: symbiotic bacteria from a reproductive organ protect bobtail squid eggs from fungal fouling. mBio, 10(5): e02376-19. DOI: 10.1128/mBio.02376-19.

Belcaid, M., G. Casaburi, S.J. McAnulty, H. Schmidbaur, A.M. Suria, S. Moriano-Gutierrez, M.S. Pankey, T.H. Oakley, N. Kremer, E.J. Koch, A.J. Collins, H. Nguyen, S. Lek, I. Goncharenko-Foster, P. Minx, E. Sodergren, G. Weinstock, D.S. Rokhsar, M. McFall-Ngai, O. Simakov, J.S. Foster, and S.V. Nyholm. 2019. Symbiotic organs shaped by distinct modes of genome evolution in cephalopods. PNAS, Jan, DOI:10.1073/pnas.1817322116.

Leonida, M.D., S. Belbekhouche, A. Benzecry, M. Peddineni, A.M. Suria, B. Carbonnier. 2018. Antibacterial hop extracts encapsulated in nanochitosan matrices. International Journal of Biological Macromolecules, 120 (A): 1335-1343. doi: 10.1016/j.ijbiomac.2018.09.003.

Gromek, S.M.*, A.M. Suria*, M.S. Fullmer, J.L. Garcia, J.P. Gogarten, S.V. Nyholm, M.J. Balunas. 2016. Leisingera sp. JC1, a bacterial isolate from Hawaiian bobtail squid eggs, produces indigoidine and differentially inhibits vibrios. Frontiers in Microbiology, 7 (September). doi:10.3389/fmicb.2016.01342.

Page updated

Google Sites

Report abuse