一株中度嗜盐菌Halomonas sp.NY-011的分离与鉴定

Isolation and characterization of a moderately halophilic bacterium Halomonas sp.NY-011

从盐生杜氏藻（Dunaliella salina）培养物内筛选到一株能在广泛NaCl浓度范围（0．5％～21％，w／v）和广泛pH值范围（pH5～11）生长的嗜碱耐盐菌NY-011．细胞形态电镜观察和生理生化分析表明，NY-011呈杆状，大小为（0．51～1．53）μm×（1．02～2．55）μm，革兰氏阴性，有荚膜，无鞭毛，不运动，好氧生长，淀粉水解酶呈阴性，接触酶呈阳性．其最适培养条件为：2％NaCl，30℃，起始pH值10．16S rDNA序列比对和构建的系统发育树表明该菌属于盐单胞菌属（Halcrmonas）．Biolog分析显示，在检测的95种碳源中，该菌仅有10种的代谢指纹能与数据库类型相匹配．且代谢情况和其亲缘关系最近的Halomonas pantelleriensis亦有差异.

An alkaliphilic and moderately halophilic bacterium, NY-011, which can survive under wide range of NaCl concentration （0.5 %-21%, w/v） and pH （5-11）, was isolated from the lab culture of a unicellular green alga, Dunaliella salina. Electron microscope investigation, physiological and biochemical tests indicated that the cells of NY-011 are rods, （0.51 - l. 53）μm × （ 1.02 - 2.55） μm, gram-negative, with capsule, without flagellum non-motile and aerophilic. NY-011 can hydrolyze starch but show no catalase activity. The optimum growth conditions are： 2 % NaCl, 30 ℃, initial pH 10. 16S rDNA alignment and phylogenesis analysis show that NY-011 is a member of the genus Halcrmonas. Biolog system analysis shows that out of 95 different carbon sources only 10 metabolism fingerprints of NY-011 can match with the database. Some characters of NY-011 distinctly differ from many other species of Halomonas, even Halomonas pantelleriensis, which is its closest member in the phylogenetic tree.