새 논 문

본 연구팀이 Journal of Eukaryotic Microbiology(JEM)에 제출한 논문(아래)이 2012년 3월 15일자로 채택되었습니다.

본 논문은 신종인 Azadinium poporum (아자디니움 포포롬)이 태평양에도 출현한다는 사실을 최초로 밝힌 논문입니다. 그 동안 Azadinium은 북해 (독일, 영국 인근)에서만 발견이 되었었습니다. Azadinium은 Azaspiracid라는 새로운 독소를 가지고 있어, 국제적으로 매우 큰 관심을 끌고 있는 종입니다. 또한 본 논문에서는 우리나라에 출현한 Azadinium은 북해에서 보고된 종들과 형태적으로 매우 유사하나, 분자생물학적으로는 다소 다르다는 사실을 밝혔습니다.

이 논문은 박사과정 Eric Potvin군의 최초의 SCI논문입니다. 2년 전 캐나다에서 석사학위를 받은 후 서울대에 입학하여, 낯선 환경 속에서도 열심히 연구하여 좋은 성과를 내게 되었습니다. 축하합니다. 그리고 본 논문이 나오기까지 도움을 주신 분들께 진심으로 감사드립니다.

First report of the photosynthetic dinoflagellate genus Azadinium in the Pacific Ocean: morphology and molecular characterization of A. cf. poporum

Éric Potvin,  Hae Jin Jeong, Nam Seon Kang, Urban Tillmann, Bernd Krock

ABSTRACT. A strain of a dinoflagellates belonging to the genus Azadinium was obtained by the incubation of sediments collected from Shiwha Bay, Korea. This report of the genus Azadinium is the first outside of northern Europe and furthermore from the Pacific Ocean. The diagnostic morphological features of the isolate very closely resemble the recently described species Azadinium poporum isolated from the North Sea. However, the shape of the 3' apical plate and the occasional morphological variations unreported from A. poporum bring minor distinctions between strains from different locations. The DNA sequences of small subunit (SSU), ITS, and large subunit (LSU) rDNA differed by 0.2%, 2.6%, and 3.6%, respectively, from those of A. poporum, whereas the COI gene was identical to those found in all strains of Azadinium. Phylogenetic analyses of the ribosomal genes generally positioned the Korean strain as a sister taxon of A. poporum. However, the Korean isolate tends to occupy a basal position within Azadinium species with ITS rDNA and LSU rDNA. Using liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS), no known azaspiracids were detected. The slight but discernible morphological differences, the distinct rDNA sequences, and the tendency of the Korean strain to diverge phylogenetically based on ITS rDNA and LSU rDNA from A. poporum do not enable us to clearly assign the isolate to A. poporum. However, these characteristics do not allow us to classify it as a distinct species, and it is therefore designated as Azadinium cf. poporum. The examination of more strains in order to find more diagnostic characteristics might enable the attribution of this material to a well defined taxonomic position.

Keywords: Azadinium, Azaspiracids, Asia, Harmful Algal Blooms, Toxin, Cryptic species, rDNA