School of Food & Biological Engineering, Jiangsu University, Zhenjiang 212013, People's Republic of China.
Syst Appl Microbiol. 2012 Feb;35(1):30-4. doi: 10.1016/j.syapm.2011.08.001. Epub 2011 Sep 1.
Two extremely halophilic archaeal strains GX3(T) and GX26(T) were isolated from the Gangxi marine solar saltern near the Weihai city of Shandong Province, China. Cells from the two strains were pleomorphic and stained Gram-negative, colonies were red-pigmented. Strains GX3(T) and GX26(T) were able to grow at 25-50 °C (optimum 37 °C), at 1.4-5.1M NaCl (optimum 3.1M), at pH 5.5-9.5 (optimum pH 7.0) and neither strain required Mg(2+) for growth. Cells lyse in distilled water and the minimal NaCl concentration to prevent cell-lysis was 8% (w/v). The major polar lipids of the two strains were PA (phosphatidic acid), PG (phosphatidylglycerol), PGP-Me (phosphatidylglycerol phosphate methyl ester) and three major glycolipids (GL1, GL2 & GL3) chromatographically identical to S-TGD-1 (sulfated galactosyl mannosy glucosyl diether), S-DGD-1 (sulfated mannosyl glucosyl diether), and DGD-1 (mannosyl glucosyl diether) respectively, an unidentified lipid (GL4) was also detected in strain GX26(T). Phylogenetic analysis based on 16S rRNA gene revealed that strain GX3(T) and strain GX26(T) formed a distinct clade with the closest relative, Haladaptatus paucihalophilus (89.9-92.4% and 90.4-92.7, respectively). The rpoB' gene similarities between strains GX3(T) and GX26(T), and between the two strains and the closest relative, Halorussus rarus TBN4(T) are 96.5%, 84.3% and 83.9%, respectively. The DNA G+C contents of strain GX3(T) and strain GX26(T) are 67.3 mol% and 67.2 mol%, respectively. The DNA-DNA hybridization value between strain GX3(T) and strain GX26(T) was 44%. The phenotypic, chemotaxonomic and phylogenetic properties suggest that strain GX3(T) and strain GX26(T) represent two novel species in a new genus within the family Halobacteriaceae, Halorubellus salinus gen. nov., sp. nov. (type strain GX3(T)=CGMCC 1.10384(T)=JCM 17115(T)) and Halorubellus litoreus sp. nov. (type strain GX26(T)=CGMCC 1.10386(T)=JCM 17117(T)).
两株极端嗜盐古菌菌株 GX3(T)和 GX26(T) 从中国山东省威海市附近的港西海洋晒盐场中分离得到。这两株菌的细胞呈多形性，革兰氏阴性染色，菌落呈红色。菌株 GX3(T)和 GX26(T) 能够在 25-50°C（最佳 37°C）、1.4-5.1M NaCl（最佳 3.1M）、pH5.5-9.5（最佳 pH7.0）的条件下生长，且两株菌的生长都不需要 Mg(2+)。细胞在蒸馏水中溶解，防止细胞溶解的最小 NaCl 浓度为 8%（w/v）。这两株菌的主要极性脂类为 PA（磷脂酸）、PG（磷脂酰甘油）、PGP-Me（磷酸甘油磷酸甲醚）和三种主要糖脂（GL1、GL2 和 GL3），它们在色谱上与 S-TGD-1（硫酸化半乳糖基甘露糖基葡萄糖基二醚）、S-DGD-1（硫酸化甘露糖基葡萄糖基二醚）和 DGD-1（甘露糖基葡萄糖基二醚）分别一致，菌株 GX26(T) 中还检测到一种未知脂质（GL4）。基于 16S rRNA 基因的系统发育分析表明，菌株 GX3(T)和菌株 GX26(T)与最接近的亲缘种 Haladaptatus paucihalophilus（分别为 89.9-92.4%和 90.4-92.7%）形成了一个独特的分支。菌株 GX3(T)和 GX26(T) 之间，以及两株菌与最接近的亲缘种 Halorussus rarus TBN4(T) 之间的 rpoB' 基因相似度分别为 96.5%、84.3%和 83.9%。菌株 GX3(T)和菌株 GX26(T) 的 DNA G+C 含量分别为 67.3 mol%和 67.2 mol%。菌株 GX3(T) 和菌株 GX26(T) 之间的 DNA-DNA 杂交值为 44%。表型、化学生态和系统发育特性表明，菌株 GX3(T)和菌株 GX26(T) 代表了盐杆菌科 Halobacteriaceae 中新属中的两个新种，盐生盐杆菌属 Halorubellus salinus gen. nov.，sp. nov.（模式菌株 GX3(T)=CGMCC 1.10384(T)=JCM 17115(T)）和海滨盐杆菌 sp. nov.（模式菌株 GX26(T)=CGMCC 1.10386(T)=JCM 17117(T)）。
