淡水蓝藻的高温适应

HIGH TEMPERATURE ADAPTATION OF FRESH WATER CYANOBACTERIUM

本文在有关文献的基础上综合分析了淡水蓝藻对高温的适应,并对淡水蓝藻高温适应机制提出了几种看法。生长在高温中的淡水蓝藻有这样一些特点:（1）不同种类对高温的适应机制稍有不同;（2）类囊体膜具有较高的稳定性;（3）藻体在受热时产生热休克蛋白以保护细胞内的酶免于热变性;（4）光合作用系统具有热稳定性;（5）DNA具有热稳定性;（6）蛋白质的合成系统具有热稳定性。其中DNA和光合作用系统的热稳定性起着关键的作用,热休克蛋白的产生和类囊体膜中脂肪酸的饱和程度是在基因水平上调控的。

The high temperature adaptation of some fresh water cyanobacteria is discussed in this paper-Six possible mechanisms for adaptation of these fresh water cyanobacteria to the high temperature have been proposed on the basis of correlating references, i. e.(1) different species of fresh water cyanobacteria have slightly different morphonogical adaptations;(2) the thylakiod membrane of these fresh water cyanobacteria has a higher thermostability;(3)these fresh water cyanobacteria produce heat shock proteins when they are in heat stress in case the enzymes are denatured;(4) the photosystem of these fresh water cyanobacteria has a higher thermostability;(5) the thermostability of DNA of these fresh water cyanobacteria plays a key part during the process of metabolism;(6) there exists a stable protein synthesizing system in these fresh water cyanobacteria. The adaptation for these fresh water cyanobcteria under high temperature is due to the coordination of the factors mentioned above, among whkh the thermostability of DNA and protein synthesizing system, the gene manipulation play an insubstitutable role during temperature variation from the lower growth limits to the higher ones.