First report of the epiphytic dinoflagellate Gambierdiscus caribaeus in the temperate waters off Jeju Island, Korea: morphology and molecular characterization.
Gambierdiscus spp. are epiphytic, benthic dinoflagellates. Some species have been shown to be toxic and cause ciguatera fish poisoning. We report, for the first time, the occurrence of Gambierdiscus caribaeus isolated from the waters off Jeju Island in Korea. Its morphology was similar to that of the original Belize strains of G. caribaeus. Gambierdiscus caribaeus has been reported in the tropical and subtropical waters of the Pacific, Gulf of Mexico, Caribbean Sea, and Floridian coast. Our report extends its range to the North Pacific Ocean. The plates of the Korean strain were arranged in a Kofoidian series of Po, 3', 7'', 6c, 6s, 5''', 1p, and 2'''', morphologically closer to other strains of G. caribaeus than to G. carpenteri. When properly aligned, its small subunit (SSU) rDNA was 0.5% different from those of Gambierdiscus sp. C-1, a strain that was isolated from the waters off eastern Japan, but was 2.4-4.0% different from those of the NOAA strains of G. caribaeus and 3.1-3.4% different from those of the NOAA strains of G. carpenteri. Additionally, the D1-D3 large subunit (LSU) rDNA sequence of the Korean strain of G. caribaeus was 4.7-5.3% different from those of the NOAA strains of G. caribaeus and 7.1-7.5% different from those of all reported G. carpenteri strains, including the NOAA strains. In phylogenetic trees based on SSU and LSU rDNA sequences, our Korean strain was basal to the clade consisting of the NOAA strains of G. caribaeus, which in turn was sister clade to all reported G. carpenteri strains.
School of Earth and Environmental Sciences, College of Natural Sciences, Seoul National University, Seoul, 151-747, Korea. hjjeong@snu.ac.kr
Hae Jin
HJ
Jeong
An Suk
AS
Lim
Se Hyeon
SH
Jang
Won Ho
WH
Yih
Nam Seon
NS
Kang
Sung Yeon
SY
Lee
Yeong Du
YD
Yoo
Hyung Seop
HS
Kim
D016000:Cluster Analysis; D016054:DNA, Protozoan / Q000737:chemistry / Q000235:genetics; D004275:DNA, Ribosomal / Q000737:chemistry / Q000235:genetics; D004141:Dinoflagellida / Q000145:classification* / Q000166:cytology / Q000235:genetics / Q000302:isolation & purification*; D020459:Genes, rRNA; D062312:Islands; D007723:Korea; D008853:Microscopy; D008969:Molecular Sequence Data; D010140:Pacific Ocean; D010802:Phylogeny; D016053:RNA, Protozoan / Q000235:genetics; D012335:RNA, Ribosomal / Q000235:genetics; D012337:RNA, Ribosomal, 18S / Q000235:genetics; D012623:Seawater / Q000469:parasitology*; D017422:Sequence Analysis, DNA
D016054:DNA, Protozoan; D004275:DNA, Ribosomal; D016053:RNA, Protozoan; D012335:RNA, Ribosomal; D012337:RNA, Ribosomal, 18S; C065096:RNA, ribosomal, 26S