북서태평양에서 Synechococcus 5.1 subcluster의 위도 및 수심에 따른 분포

Abstract

Synechococcus are ubiquitously distributed throughout the world’s oceans. However, theirabundances are much lower than Prochlorococcus in oligotrophic open oceans. Thus,Synechococcus diversity has not been studied in detail for oligotrophic open oceans. Inthis study, high-throughput pyrosequencing using a primer specific to Synechococcus 5.1sub-cluster was applied to investigate Synechococcus diversity in detail for the western northPacific Ocean. Despite of low abundances, very diverse Synechococcus clades appeared. CladeII was a predominant Synechococcus. However, diverse clades in sub-cluster 5.1 excludingclades V, VI and WPC2 were appeared. Among them, clades WPC3, WPC5 and WPC6 wereoccasionally more abundant than clades II. Especially, clades WPC3 and WPC5 were foundsignificantly at lower euphotic depths at about 75 m or less. On the other hand, clade WPC6distributed broadly with a relatively higher fraction at mid-euphotic depths. WPC6 also showedrelatively high fraction at low latitude less than 20 degree north. Further, a number of sequencesnot affiliated with the previously designed clades were exhibited in lower euphotic depths,suggesting a possibility of presence of unidentified and low light-adapted Synechococcus.ophic open oceans. Inthis study, high-throughput pyrosequencing using a primer specific to Synechococcus 5.1sub-cluster was applied to investigate Synechococcus diversity in detail for the western northPacific Ocean. Despite of low abundances, very diverse Synechococcus clades appeared. CladeII was a predominant Synechococcus. However, diverse clades in sub-cluster 5.1 excludingclades V, VI and WPC2 were appeared. Among them, clades WPC3, WPC5 and WPC6 wereoccasionally more abundant than clades II. Especially, clades WPC3 and WPC5 were foundsignificantly at lower euphotic depths at about 75 m or less. On the other hand, clade WPC6distributed broadly with a relatively higher fraction at mid-euphotic dept