Takumi Iijima, a second-year doctoral student at the United Graduate School of Agricultural Sciences, Ehime University, affiliated with Kochi University, was honored with the Outstanding Oral Presentation Award at the 25th Annual Meeting of the Marine Biotechnology Society, held from May 24 to 25, 2025, in Kure City, Hiroshima Prefecture.
Award-winning Presentation
“Development of a PNA Clamp to Specifically Inhibit PCR Amplification of rDNA in Bivalves”
Tetrodotoxin (TTX), a potent neurotoxin found in pufferfish, has in recent years also been detected in bivalves such as scallops. Because bivalves are filter feeders, it is believed that they may accumulate the toxin by ingesting certain plankton species. Identifying these plankton is crucial for food safety and toxin source tracking.
One method used to investigate the plankton DNA within the digestive tracts of bivalves is known as metabarcoding. However, a key challenge has been the co-amplification of the host bivalve’s DNA during PCR, making it difficult to isolate plankton-specific information.
To overcome this difficulty, Iijima, under the guidance of Professor Masao Adachi, successfully developed a PNA (peptide nucleic acid) clamp that selectively inhibits the amplification of scallop DNA. This innovation enables researchers to more efficiently extract and analyze plankton DNA alone. This new method will be applied to comprehensively identify the types of plankton consumed by scallops and to pinpoint the specific organisms responsible for TTX production, paving the way for a better understanding of toxin accumulation in the food chain.
＜The United Graduate School of Agricultural Sciences＞