Choi Dong Han, Noh Jae Hoon
Marine Living Resources Research Department, Korea Ocean Research and Development Institute, Ansan 426-744, Korea.
FEMS Microbiol Ecol. 2009 Sep;69(3):439-48. doi: 10.1111/j.1574-6941.2009.00729.x. Epub 2009 Jun 22.
Phylogenetic relationships among 33 Synechococcus strains isolated from the East China Sea (ECS) and the East Sea (ES) were studied based on 16S rRNA gene sequences and 16S-23S rRNA gene internal transcribed spacer (ITS) sequences. Pigment patterns of the culture strains were also examined. Based on 16S rRNA gene and ITS sequence phylogenies, the Synechococcus isolates were clustered into 10 clades, among which eight were previously identified and two were novel. Half of the culture strains belonged to clade V or VI. All strains that clustered into novel clades exhibited both phycoerythrobilin and phycourobilin. Interestingly, the pigment compositions of isolates belonging to clades V and VI differed from those reported for other oceanic regions. None of the isolates in clade V showed phycourobilin, whereas strains in clade VI exhibited both phycourobilin and phycoerythrobilin, which is in contrast to previous studies. The presence of novel lineages and the different pigment patterns in the ECS and the ES suggests the possibility that some Synechococcus lineages are distributed only in geographically restricted areas and have evolved in these regions. Therefore, further elucidation of the physiological, ecological, and genetic characteristics of the diverse Synechococcus strains is required to understand their spatial and geographical distribution.
基于16S rRNA基因序列和16S-23S rRNA基因内部转录间隔区（ITS）序列，研究了从中国东海（ECS）和东海（ES）分离出的33株聚球藻菌株之间的系统发育关系。还检测了培养菌株的色素模式。基于16S rRNA基因和ITS序列系统发育，聚球藻分离株被聚类为10个分支，其中8个是先前已鉴定的，2个是新的。一半的培养菌株属于分支V或VI。所有聚类到新分支的菌株都同时含有藻红素胆素和藻尿胆素。有趣的是，属于分支V和VI的分离株的色素组成与其他海洋区域报道的不同。分支V中的分离株均未显示藻尿胆素，而分支VI中的菌株同时含有藻尿胆素和藻红素胆素，这与先前的研究相反。中国东海和东海中存在新的谱系以及不同的色素模式，这表明一些聚球藻谱系可能仅分布在地理上受限的区域并在这些区域中进化。因此，需要进一步阐明不同聚球藻菌株的生理、生态和遗传特征，以了解它们的空间和地理分布。
