Leibniz-Institut DSMZ - Deutsche Sammlung von Mikroorganismen und Zellkulturen, Braunschweig, Germany.
Bereich Mikrobiologie, Biologie I, Ludwig-Maximilians-Universität München, Planegg, Martinsried, Germany.
Int J Syst Evol Microbiol. 2013 Apr;63(Pt 4):1342-1349. doi: 10.1099/ijs.0.043133-0. Epub 2012 Jul 13.
A previously undescribed aerobic, non-sporulating bacterium, strain G1A_585(T), was isolated from an oligotrophic freshwater lake in Bavaria, Germany. The rod-shaped cells were Gram-stain-negative and non-motile. Based on 16S rRNA gene sequence similarity, strain G1A_585(T) was a member of the family Sphingomonadaceae and shared <95.2 % similarity with type strains of all members of the most closely related genus, Sphingopyxis. Phyogenetically, the isolate shared a root with strains of three marine species, Sphingopyxis flavimaris DSM 16223(T), Sphingopyxis marina DSM 22363(T) and Sphingopyxis litoris DSM 22379(T). The polar lipids of strain G1A_585(T) were diphosphatidylglycerol, phosphatidylglycerol, phosphatidylethanolamine, phosphatidylmonomethylethanolamine, phosphatidyldimethylethanolamine, phosphatidylcholine, sphingoglycolipids, three glycolipids and one unknown lipid. Ubiquinone-10 was the dominant quinone (93.1 %) and ubiquinone-9 (6.5 %) was also detected. The major cellular fatty acids were summed feature 8 (C18 : 1ω7c and/or C18 : 1ω6c; 38.2 %); C16 : 1ω7c (33.6 %) and C14 : 0 2-OH (17.8 %). The major polyamine was spermidine and traces of 1,3-diaminopropane, putrescine and spermine were also detected. The DNA G+C content of strain G1A_585(T) was 55.7 mol% and the isolate was oxidase- and catalase-positive. Based on the phylogenetic relationship, the low DNA G+C content compared with most other members of the genus Sphingopyxis and the presence of signature nucleotides in the 16S rRNA gene sequence, a novel species in a new genus and species, Sphingorhabdus planktonica gen. nov., sp. nov., is proposed; the type strain of Sphingorhabdus planktonica is G1A_585(T) ( = DSM 25081(T) = LMG 26646(T)). Because Sphingopyxis flavimaris DSM 16223(T), Sphingopyxis marina DSM 22363(T) and Sphingopyxis litoris DSM 22379(T) form a phylogenetic group together with strain G1A_585(T) that is clearly separated from all other known Sphingopyxis strains and share signature nucleotides, these three Sphingopyxis strains are reclassified as members of the proposed novel genus Sphingorhabdus: Sphingorhabdus flavimaris comb. nov. (type strain SW-151(T) = DSM 16223(T) = KCTC 12232(T)), Sphingorhabdus marina comb. nov. (type strain FR1087(T) = DSM 22363(T) = IMSNU 14132(T) = KCTC 12763(T) = JCM 14161(T)) and Sphingorhabdus litoris comb. nov. (type strain FR1093(T) = DSM 22379(T) = IMSNU 14133(T) = KCTC 12764(T) = JCM 14162(T)).
一株先前未被描述的需氧、不产芽孢的细菌，菌株 G1A_585(T)，从德国巴伐利亚州的一个贫营养淡水湖中分离得到。该杆状细胞革兰氏染色阴性，不运动。基于 16S rRNA 基因序列相似性，菌株 G1A_585(T)是鞘氨醇单胞菌科的一个成员，与最密切相关属的所有成员的模式株相似性均<95.2%，与鞘氨醇单胞菌属的相似度最高。在系统发育上，该分离株与三种海洋物种的菌株具有共同的根源，即黄丝菌素 flavimaris DSM 16223(T)、海鞘单胞菌 DSM 22363(T)和海鞘单胞菌 DSM 22379(T)。菌株 G1A_585(T)的极性脂包括双磷脂酰甘油、磷脂酰甘油、磷脂酰乙醇胺、磷脂单甲基乙醇胺、磷脂二甲基乙醇胺、磷脂酰胆碱、神经鞘糖脂、三种糖脂和一种未知脂质。主要醌类为泛醌-10（93.1%），也检测到泛醌-9（6.5%）。主要的细胞脂肪酸是总和特征 8（C18:1ω7c 和/或 C18:1ω6c；38.2%）；C16:1ω7c（33.6%）和 C14:0 2-OH（17.8%）。主要聚胺是亚精胺，也检测到痕量的 1,3-二氨基丙烷、腐胺和精胺。菌株 G1A_585(T)的 DNA G+C 含量为 55.7 mol%，为氧化酶阳性、过氧化氢酶阳性。基于系统发育关系、与大多数其他鞘氨醇单胞菌属成员相比相对较低的 DNA G+C 含量以及 16S rRNA 基因序列中的特征核苷酸，提出了一个新属和新种，浮游鞘氨醇单胞菌属，浮游鞘氨醇单胞菌种，新属新种；浮游鞘氨醇单胞菌的模式株是 G1A_585(T)（=DSM 25081(T)=LMG 26646(T)）。由于黄丝菌素 flavimaris DSM 16223(T)、海鞘单胞菌 DSM 22363(T)和海鞘单胞菌 DSM 22379(T)与菌株 G1A_585(T)一起形成了一个与所有其他已知鞘氨醇单胞菌菌株明显分离的系统发育群，并且具有特征核苷酸，因此这三种鞘氨醇单胞菌菌株被重新分类为提议的新属浮游鞘氨醇单胞菌的成员：黄丝菌素 flavimaris comb. nov.（模式株 SW-151(T)=DSM 16223(T)=KCTC 12232(T)）、海鞘单胞菌 marina comb. nov.（模式株 FR1087(T)=DSM 22363(T)=IMSNU 14132(T)=KCTC 12763(T)=JCM 14161(T)）和海鞘单胞菌 litoris comb. nov.（模式株 FR1093(T)=DSM 22379(T)=IMSNU 14133(T)=KCTC 12764(T)=JCM 14162(T)）。
