摘要
杜氏盐藻在适应外界盐浓度变化的过程中,甘油是其主要的渗透调节物质。低渗处理提高藻细胞的呼吸速率60%以上;高渗处理对呼吸无明显影响,但大大刺激光合放氧速率。呼吸链的细胞色素电子传递链抑制剂KCN和交替氧化酶抑制剂SHAM对杜氏藻渗透调节过程中的呼吸.胞内甘油、ATP、淀粉会量的变化有不同的抑制效果。低渗情况下,胞内甘油转化为淀粉,所需能量由正常呼吸链和交替氧化酶途径同时提供;高渗情况下.淀粉则降解为甘油,光下甘油合成的能量主要由光合电子链提供,暗中则由正常呼吸链提供。
Intracellular glycerol content of D.salina increased after hyperosmotic shock and decreased after hypoosmotic shock. The respiration of algal cells was highly stimulated by hypoosmotic shock, oxygen uptake Per cell increased by 60% or more. Hyperosmotic shock stimulated the respiration of algal cell much less than hypoosmotic shock. KCN 1 mmol/L and SHAM 2 mmol/L inhibited the change of respiration and the contents of intracellular glycerol, ATP and starch during osmoregulation caused by hypoosmotic shock, but they had more complicated effects on the metabolism during hyperosmotic regulation. It is concluded that during the adaptation to hypoosmotic shock the energy needed for glycerol degradation is supplied by both normal respiration pathway (KCN sensitive) and alternative pathwaySHAM sensitive); while that during the adaptation to hyperosmotic shock is supplied by normal pathway in darkness, and mainly by electron transport chain in light. During hypoosmotic regulation intracellular starch content increased and the glycerol content decreased, during hyperosmotic regulation starch content decreased while glycerol content increased.
关键词
杜氏藻
渗透调节
甘油
代谢
Dunaliella salina, osmoregulation, glycerol. KCN. salicylhydroxamic acid