中文摘要：

对本实验室分离到的一株中度嗜盐菌Halomonas sp.NY-011的耐盐特性和耐盐机理进行了初步研究.NY-011在LB培养基中最大能耐受260g/LNaCl浓度,在M63培养基中能耐受大于150g/LNaCl浓度.Cl-的缺少对NY-011的耐盐生长有明显抑制,K＋较Li＋和Mg2＋更适合于为NY-011提供内部渗透压力.NY-011通过在胞内积累K＋、游离氨基酸及其他相容性溶质对抗胞外渗透压力.NY-011胞内相容性溶质组成随培养基NaCl浓度变化而变化,四氢嘧啶是最主要的组成成分,含量随培养基NaCl浓度增加而增加,120g/LNaCl时浓度可达到71.5mg/g干重.NY-011还可吸收胞外的四氢嘧啶和甜菜碱以平衡外界高渗透压.随着培养基中NaCl浓度的提高,NY-011菌体蛋白的合成受到明显抑制.图5表2参24

英文摘要：

A moderately halophilic bacterium Halomonas sp.NY-11 was isolated from our laboratory,and its osmotolerance property and mechanism were studied.Strain NY-11 could maximally tolerate 260 g/L NaCl in LB medium and its tolerance to NaCl was over 150 g/L in M63.The absence of chloridion would obviously inhibit the growth of NY-11 under salt and potassium was more suitable to provide intracellular osmotic pressure than lithium and magnesium.NY-11 accumulated potassium,free amino acids and other compatible solutes to equilibrate extracellulary osmotic pressure.The components of the intracellular compatible solutes of NY-11 varied with the changing of NaCl concentrations in medium,while ectoine,which was the most important component,increased with the increasing of NaCl concentration,reaching 71.5 mg/g by dry weight under 120 g/L NaCl.NY-11 could import extracellular ectoine and glycine betaine to improve osmotolerance,and the synthesis of protein was obviously depressed by the increased NaCl concentration in medium.Fig 5,Tab 2,Ref 24