Na Hyunsoo, Kim Seil, Moon Eun Young, Chun Jongsik
School of Biological Sciences, Seoul National University, Shillim-dong, Kwanak-gu, Seoul 151-742, Republic of Korea.
Int J Syst Evol Microbiol. 2009 Sep;59(Pt 9):2241-6. doi: 10.1099/ijs.0.009027-0. Epub 2009 Jul 20.
A facultatively anaerobic, moderately halophilic, Gram-negative, filamentous bacterium, designated JC2469T, was isolated from tidal flat sediment in Korea. Phylogenetic analysis based on 16S rRNA gene sequences showed that the isolate belonged to the phylum Bacteroidetes and its closest taxonomic relative was Cytophaga fermentans NCIMB 2218T (89.6% sequence similarity). Cells appeared as filaments during exponential growth, but became fragmented to rods at stationary phase. Spherical cells were also observed in aged cultures. Strain JC2469T contained iso-C15:0 (56.2%) and MK-7 as the predominant fatty acid and respiratory quinone, respectively. On the basis of evidence from this polyphasic study, the isolate showed substantial differences from other genera. The phylogenetic and physiological data of the present study strongly suggest that the isolate represents a novel genus and species, for which the name Marinifilum fragile gen. nov., sp. nov. is proposed. The type strain of Marinifilum fragile is JC2469T (=IMSNU 14138T=KCTC 22488T=JCM 15579T).
从韩国潮滩沉积物中分离出一株兼性厌氧、中度嗜盐、革兰氏阴性丝状细菌，命名为JC2469T。基于16S rRNA基因序列的系统发育分析表明，该分离株属于拟杆菌门，与其亲缘关系最近的分类单元是发酵噬纤维菌Cytophaga fermentans NCIMB 2218T（序列相似性为89.6%）。细胞在指数生长期呈丝状，但在稳定期破碎成杆状。在老化培养物中也观察到球形细胞。菌株JC2469T分别以异-C15:0（56.2%）和MK-7作为主要脂肪酸和呼吸醌。基于这项多相研究的证据，该分离株与其他属存在显著差异。本研究的系统发育和生理数据强烈表明，该分离株代表一个新的属和种，为此提议命名为脆弱海丝菌属（Marinifilum），新属，新种。脆弱海丝菌的模式菌株为JC2469T（=IMSNU 14138T=KCTC 22488T=JCM 15579T）。
