Han Dong, Cui Heng-Lin
School of Food and Biological Engineering, Jiangsu University, 301 Xuefu Road, Jingkou District, Zhenjiang, 212013, People's Republic of China.
Antonie Van Leeuwenhoek. 2015 Jan;107(1):217-23. doi: 10.1007/s10482-014-0319-9. Epub 2014 Nov 1.
Two halophilic archaeal strains, R60(T) and R61, were isolated from the brine of salted brown alga Laminaria. Cells of the two strains were observed to be rod-shaped, stain Gram-negative and to lyse in distilled water. Strain R60(T) was found to contain gas vacuoles and to produce pink-pigmented colonies, while strain R61 lacked gas vacuoles and produces red-pigmented colonies. Both strains were found to be able to grow at 20-50 °C (optimum 30 °C), at 1.7-4.8 M NaCl (optimum 2.6-3.1 M NaCl), at 0-1.0 M MgCl2 (optimum 0.005-0.1 M MgCl2) and at pH 6.0-9.5 (optimum pH 7.0). The major polar lipids were identified as phosphatidylglycerol, phosphatidylglycerol phosphate methyl ester, phosphatidylglycerol sulfate and one major glycolipid chromatographically identical to a sulfated mannosyl glucosyl diether produced by Halorubrum members of the Halobacteriaceae. The 16S rRNA gene sequences of the two strains were 99.9 % identical, showing 94.6-98.0 % similarity to those of members of the genus Halorubrum. The EF-2 gene similarity between strains R60(T) and R60 was 100 % and showed 84.6-94.5 % similarity to those of members of the genus Halorubrum. The DNA G+C contents of the two strains were determined to be 63.0 mol %. The DNA-DNA hybridization value between strain R60(T) and strain R61 was 92 % and the two strains showed low DNA-DNA relatedness with the most related members of Halorubrum. The phenotypic, chemotaxonomic and phylogenetic properties suggest that strain R60(T) (= CGMCC 1.12689(T) = JCM 30040(T)) and strain R61 (= CGMCC 1.12696) represent a novel species of the genus Halorubrum, for which the name Halorubrum laminariae sp. nov. is proposed.
从盐渍褐藻海带的卤水中分离出两株嗜盐古菌菌株，R60(T)和R61。观察到这两株菌株的细胞呈杆状，革兰氏染色阴性，在蒸馏水中会裂解。发现菌株R60(T)含有气泡，产生粉红色菌落，而菌株R61缺乏气泡，产生红色菌落。两株菌株均能在20-50℃（最适温度30℃）、1.7-4.8M NaCl（最适浓度2.6-3.1M NaCl）、0-1.0M MgCl2（最适浓度0.005-0.1M MgCl2）以及pH 6.0-9.5（最适pH 7.0）的条件下生长。主要极性脂类被鉴定为磷脂酰甘油、磷脂酰甘油磷酸甲酯、磷脂酰甘油硫酸酯以及一种主要糖脂，其色谱特征与盐杆菌科嗜盐红菌属成员产生的硫酸化甘露糖基葡糖基二醚相同。两株菌株的16S rRNA基因序列相似度为99.9%，与嗜盐红菌属成员的序列相似度为94.6-98.0%。菌株R60(T)和R61之间的EF-2基因相似度为100%，与嗜盐红菌属成员的相似度为84.6-94.5%。测定两株菌株的DNA G+C含量为63.0mol%。菌株R60(T)和菌株R61之间的DNA-DNA杂交值为92%，并且这两株菌株与嗜盐红菌属关系最密切的成员显示出较低的DNA-DNA相关性。表型、化学分类和系统发育特征表明菌株R60(T)(=CGMCC 1.12689(T)=JCM 30040(T))和菌株R61(=CGMCC 1.12696)代表嗜盐红菌属的一个新物种，为此提出新名称海带嗜盐红菌（Halorubrum laminariae sp. nov.）。
