Characterization of the Microbial Community of the Clinging Jellyfish, Gonionemus vertens

The orange and green iridescent colonies that grabbed our attention from the Gonionemus Vertens, Clinging Jellyfish have been the subject of the semester’s research this far. There are currently nine different iridescent isolates that are the focus of my current investigations. Although this is not a novel group of Bacteria, these bacteria have never been associated or isolated from invertebrates. The Clinging Jellyfish were originally collected while wading near Rye Beach this summer. After isolating some 28 strains from the Clinging Jellyfish, I amplified the 16srRNA gene and sent these out for genetic sequencing. After getting my results I was able to compare the new sequences from the isolates to existing bacterial representatives in the GenBank database. All of my strains were grown up and archived in glycerol stock in the -80°C freezer. These archived strains will be the working stock for future experiments and prevent the loss of the isolated cultures. Each of the isolates were restreaked on media to check for pure colonies and resequenced in order to confirm the identity of the archived isolates.

I am interested in the role of the iridescent bacterium associated with the Clinging Jellyfish and proposed that they may imbue the host with certain optical properties that may help it survive. I will conduct some future experiments determine if the bacteria could directly cause a change in the properties of the host.

We have taken a further look into each of the iridescent colonies and more specifically how they are categorized according to their genus. From the sequence identifications, it has become apparent that the two dominant genera in our samples are Tenacibaculum and Pseudoalteromonas. The genus Pseudoalteromonas is of special interest to us because has been found to produce compounds with antimicrobial, algicidal, antifouling and many other pharmaceutically relevant properties. There have been no known genera of Pseudoalteromonas that exhibit this reflective property and our lab plans to sequence the full bacterial genome and further characterize its metabolic properties.

As both of these genera exhibit gliding motility that may play a role in the colonization of the hosts, I will characterize the gliding motility and potentially use motility as a phenotype for future genetic experiments as time permits.

Characterization of the Microbial Community of the Accessory Nidamental Gland of the Longfin inshore squid, Loligo pealei

The 16srRNA gene from cultured isolates from the squid accessory nidamental gland was amplified using PCR and sent out for sequencing. Results from the 8 initial isolates came back, allowing us to identify the different genera of bacteria associated with the squid. The amplified 16srRNA gene that was amplified was almost the entire length of the gene allowing for a reliable identification of each bacterial isolate. The two different primers (8F, 1514R) utilized caused replication from different sides of the DNA strand. From the two independent sequencing reactions, a contiguous DNA sequence was aligned with CodonCode Aligner. We performed a Standard Nucleotide BLAST (NCBI) in attempt to find closely related bacteria and other invertebrates that might be associated.

These basic molecular and microbiological techniques were applied to an unsuspected discovery of invasive Clinging Jellyfish, Gonionemus vertens,  that were discovered in July during research in the Long Island Sound. I have isolated 31 different bacterial colonies derived from a single cling jellyfish specimen. We have gone through the process of isolating several samples, amplifying the 16srRNA  gene as well as characterizing the basic bacterial morphology. The process of isolating these Clinging Jellyfish bacterial isolates revealed a number of colonies that had a green or orange iridescence. We are interested in identifying these novel bacteria and would like to discover the role of this iridescent bacteria with this jellyfish. After the 16srRNA gene is amplified, cleaned up and sequenced, they will be sent out for sequencing. From there, we will once again be able to further classify and explore the different type of bacteria that are associated with the Clinging jellyfish.

Characterization of the Microbial Community of the Accessory Nidamental Gland of the Longfin inshore squid, Loligo pealei

The title of our experiment is Characterization of the Microbial Community of the Accessory Nidamental Gland of the Longfin inshore squid, Loligo pealei. The research that is being undertaken is focusing in on the symbiotic relationship that is present between marine organisms and the mutualistically beneficial bacteria that grows on these organisms. The foundation of this research was interest in the nidamental gland of the female reproductive organ in squids. The nidamental gland is responsible for coating the eggs with a jelly like substance that is integrated with bacteria to serve as a protective barrier against predators and fowling. If this bacteria is able to be characterized, The properties that allows it to protect the eggs will be understood and potentially be beneficial in other ways. Understanding this bacteria will be attempted through 16S rRNA gene sequencing. Results will assist in understanding of marine symbiotic organisms and how they function. This will be the first study addressing the microbial population of the Longfin inshore Squid nidamental gland as well as their egg cases.


So far, many efforts have been made in reference to lab training for the experimentation itself. LBS agar plates were created in order to perform 3 way streaks and isolate particular bacteria from the marine symbionts. Squid, as well as jellyfish that were collected through wading, were the subjects of bacteria isolation. The process of isolating the bacteria from the jellyfish was extensive, beginning with euthanization of the jellyfish (through freezing),  macerating it, rinsing it with 3x deionized water and then vortexing it. Through performing a three way streak of this sample, particular colonies of bacteria were able to be isolated and examined individually. Colony PCR was performed following this and the samples were then inserted into gel in order to perform gel electrophoresis. PCR clean up was then undertaken using a Qiagen kit. This is done in order to prepare the DNA samples that were amplified to be sequenced. Twelve different bacteria samples were successfully amplified through PCR and able to be sequenced in the lab so further characterization of the bacterial colonies can occur in the future.