Li Juan, Kudo Chisaki, Tonouchi Akio
United Graduate School of Agricultural Sciences, Iwate University, 18-8 Ueda 3-chome, Morioka, Iwate, 020-8550, Japan.
Faculty of Agriculture and Life Science, Hirosaki University, 3 Bunkyo-cho, Hirosaki, Aomori, 036-8561, Japan.
Arch Microbiol. 2018 Mar;200(2):291-297. doi: 10.1007/s00203-017-1443-5. Epub 2017 Oct 28.
A bacterial strain designated PtRA-8 was isolated from the trunk surface of a Japanese aspen tree (Populus tremula var. sieboldii). Cells of strain PtRA-8 were aerobic, non-motile, non-spore forming, Gram-stain-negative rods, 1.0‒2.0 µm in width and 3.0‒10.0 µm in length. The pH range for growth was between 5.5 and 7.5, with an optimum at 6.5. The temperature range for growth was between 10 and 37 °C, with an optimum at around 25‒30 °C. Strain PtRA-8 was highly resistant to UV irradiation, similar to its Deinococcus relatives. The respiratory quinone was menaquinone MK-8. The major cellular fatty acids (> 10% of the total fatty acid content) were iso-C (17.8%), C (15.0%), iso-C (10.4%), and iso-C ω9c/C10-methyl (22.2%). The polar lipids consisted of four unidentified glycolipids, two unidentified aminolipids, two unidentified phospholipids, and three unidentified polar lipids. The peptidoglycan was A3β-type containing glutamic acid, glycine, alanine, and ornithine. The DNA G + C content of strain PtRA-8 was 68.2 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain PtRA-8 was closely related to "Deinococcus radioresistens" 8A (97.4%), Deinococcus metalli DSM 27521 (95.7%), and Deinococcus yunweiensis YIM 007 (94.5%). The DNA-DNA hybridization experiments between strain PtRA-8 and its relatives yielded relatedness values below 70%. Based on the polyphasic evidence, we concluded that strain PtRA-8 represents a novel species within the genus Deinococcus, for which the name Deinococcus populi is proposed. The type strain of D. populi is PtRA-8 (= DSM 29820= NBRC 110763; DPD TaxonNumber TA00271).
从日本山杨（Populus tremula var. sieboldii）树干表面分离出一株名为PtRA - 8的细菌菌株。PtRA - 8菌株的细胞为需氧型，无运动性，不形成芽孢，革兰氏染色阴性杆菌，宽度为1.0 - 2.0 µm，长度为3.0 - 10.0 µm。生长的pH范围在5.5至7.5之间，最适pH为6.5。生长的温度范围在10至37°C之间，最适温度约为25 - 30°C。PtRA - 8菌株对紫外线辐射具有高度抗性，与其嗜放射球菌属的亲缘关系类似。呼吸醌为甲基萘醌MK - 8。主要的细胞脂肪酸（占总脂肪酸含量的>10%）为异C（17.8%）、C（15.0%）、异C（10.4%）和异C ω9c/C10 - 甲基（22.2%）。极性脂质由四种未鉴定的糖脂、两种未鉴定的氨基脂、两种未鉴定的磷脂和三种未鉴定的极性脂质组成。肽聚糖为含谷氨酸、甘氨酸、丙氨酸和鸟氨酸的A3β型。PtRA - 8菌株的DNA G + C含量为68.2 mol%。基于16S rRNA基因序列的系统发育分析表明，PtRA - 8菌株与“嗜放射栖热菌”8A（97.4%）、金属嗜放射球菌DSM 27521（95.7%）和云南嗜放射球菌YIM 007（94.5%）密切相关。PtRA - 8菌株与其亲缘关系菌株之间的DNA - DNA杂交实验产生的相关性值低于70%。基于多相证据，我们得出结论，PtRA - 8菌株代表嗜放射球菌属内的一个新物种，为此提出名为杨树嗜放射球菌（Deinococcus populi）的名称。杨树嗜放射球菌的模式菌株为PtRA - 8（= DSM 29820 = NBRC 110763；DPD分类编号TA00271）。
