Research Center for Inland Seas, Kobe University, Kobe, 658-0022, Japan.
J Microbiol. 2010 Apr;48(2):160-4. doi: 10.1007/s12275-010-0018-9. Epub 2010 May 1.
A novel gram-negative, aerobic, moderate halophilic, and psychrotolerant bacterium, designated as strain H7(T), was isolated from a hypersaline lake located in Skarvsnes, Antarctica. Cells were filaments with varying lengths. Coccoid bodies developed in old cultures. Growth occurred with 0.5-15% (w/v) NaCl (optimum, 5.8-7.0%), at pH 6.0-10.0 (optimum, pH 7.0-8.0), and at 10-28 degrees C (optimum, 25 degrees C). The strain had a G+C content of 34.9 mol%, which is within the range of 32-36 mol% reported for the genus Psychroflexus. Chemotaxonomic data (major respiratory quinone: MK-6; major fatty acids: aC(15:0), iC(16:0) 3-OH, and aC(15: 1) A) supported the classification of strain H7(T) within the genus Psychroflexus. Phylogenetic analysis based on 16S rRNA gene sequences indicated that strain H7(T) should be assigned to the genus Psychroflexus and has a homology with Psychroflexus salinarum (98.2%), P. sediminis (96.1%), P. torquis (95.2%), P. tropicus (95.8%), and P. gondwanense (92.2%). Strain H7 is not identified as P. salinarum because that DNA-DNA hybridization data were 8.5% between strain H7(T) and P. salinarum. The combination of phylogenetic analysis, DNA-DNA hybridization data, phenotypic characteristics, and chemotaxonomic differences supported the view that strain H7(T) represents a novel species of the genus Psychroflexus. The name Psychroflexus lacisalsi is proposed, and the type strain is H7(T) (=JCM 16231(T) =KACC 14089(T)).
一株新的革兰氏阴性、需氧、中度嗜盐和耐冷菌，被命名为 H7(T) 菌株，从南极洲斯卡夫尼斯的一个高盐湖中分离得到。细胞是具有不同长度的丝状。老培养物中会形成球菌。在 0.5-15%（w/v）NaCl（最佳，5.8-7.0%）、pH 6.0-10.0（最佳，pH 7.0-8.0）和 10-28°C（最佳，25°C）下生长。该菌株的 G+C 含量为 34.9 mol%，属于 Psychroflexus 属报道的 32-36 mol%范围。化学分类学数据（主要呼吸醌：MK-6；主要脂肪酸：aC(15:0)、iC(16:0) 3-OH 和 aC(15:1) A）支持 H7(T) 菌株在 Psychroflexus 属内的分类。基于 16S rRNA 基因序列的系统发育分析表明，H7(T) 菌株应归属于 Psychroflexus 属，与 Psychroflexus salinarum（98.2%）、P. sediminis（96.1%）、P. torquis（95.2%）、P. tropicus（95.8%）和 P. gondwanense（92.2%）有同源性。菌株 H7 不能被鉴定为 P. salinarum，因为 H7(T) 菌株与 P. salinarum 之间的 DNA-DNA 杂交数据为 8.5%。系统发育分析、DNA-DNA 杂交数据、表型特征和化学分类学差异的结合支持了这样的观点，即菌株 H7(T) 代表了 Psychroflexus 属的一个新种。提议使用 Psychroflexus lacisalsi 这个名称，其模式菌株为 H7(T)（=JCM 16231(T)=KACC 14089(T)）。
