OSMOTIC ADJUSTMENT AND ORGANIC SOLUTE ACCUMULATION IN UNICELLULAR CYANOBACTERIA FROM FRESH-WATER AND MARINE HABITATS
OSMOTIC ADJUSTMENT AND ORGANIC SOLUTE ACCUMULATION IN UNICELLULAR CYANOBACTERIA FROM FRESH-WATER AND MARINE HABITATS
复制标题
DOI：
10.1007/bf00393037
复制
发表时间：
1985-01-01
期刊：
影响因子：
2.4
通讯作者：
STEWART, WDP
中科院分区：
文献类型：
--
作者：
REED, RH;STEWART, WDP
已经在从淡水到 300% 海水 (100%=35.permill.S) 的一系列外部盐度范围内研究了单细胞蓝藻的 26 个无菌分离株中存在的低分子量碳水化合物和季铵化合物的细胞内浓度。在所有情况下，单一碳水化合物，蔗糖或葡萄糖基甘油，被确定为主要的有机渗透剂，显示出对外部盐浓度的响应的主要变化；季铵化合物的渗透量微不足道。来自盐生地的九个分离株和五个淡水分离株以初级渗透剂的形式积累了葡萄糖基甘油；还存在微量的蔗糖。其余十二个淡水菌株积累蔗糖作为唯一的渗透剂。葡萄糖甘油积累菌株可以在最宽的盐度范围（高达 200% 至 250% 海水）中生长，无论是从盐水还是非盐水生境中分离出来。积累蔗糖的菌株更加狭盐，仅在高达 50% 至 100% 的海水中生长，并且在高盐介质（> 100% 海水）中没有表现出持续生长。数据表明（1）葡萄糖甘油积累并非海洋蓝细菌所独有，（2）生长的盐度上限可能与有机溶质积累有关，而不是与栖息地有关，葡萄糖甘油积累菌株在盐胁迫条件下比蔗糖积累菌株具有更大的生长潜力。
The intracellular concentrations of low-molecular weight carbohydrates and quaternary ammonium compounds present in 26 axenic isolates of unicellular cyanobacteria have been studied over a range of external salinity from freshwater up to 300% seawater (100%=35.permill. S). In all cases, a single carbohydrate, either sucrose or glucosylglycerol, was identified as the principal organic osmoticum, showing major variation in response to the external salt concentration; quaternary ammonium compounds were present in osmotically insigificant amounts. Glucosylglycerol was accumulated as primary osmoticum by nine of the isolates from saline habitats and by five of the freshwater isolates; trace amounts of sucrose were also present. The remaining twelve freshwater strains accumulated sucrose as sole osmoticum. Glucosyglycerol-accumulating strains grew over the widest salinity range (up to 200 to 250% seawater), whether isolated from saline or non-saline habitats. Sucrose-accumulating strains were more stenohaline, growing only in up to 50 to 100% seawater and showing no sustained growth in hypersaline media (> 100% seawater). The data suggest that (1) glucosyglycerol accumulation is not unique to marine cyanobacteria, and (2) the upper salinity limit for growth may be linked to organic solute accumulation, rather than habitat, with glucosylglycerol-accumulating isolates having a greater potential for growth in salt-stressed conditions than sucrose accumulators.