Genetic engineering of temperature stress tolerance

gombos博士于1995年9月6日至12月1日在国家基础生物学研究所工作。他与murata博士和hayashi博士一起研究了Synechocystis sp.PCC 6803在低温下光系统II的光抑制作用。将聚囊藻细胞暴露在不同时期的强光下诱导光抑制，然后在室温弱光下从光抑制状态恢复光合机制。结果表明，光抑制被分为两个组分；一个是可逆的，另一个是不可逆的。可逆成分可以用光系统II复合体中D1蛋白的周转来解释。不可逆组分的研究还不够深入，其分子机制也不清楚。从生理学的角度看，不可逆的光抑制对光合生物是有害的，而可逆的光抑制则使光合作用在时间上受到抑制。1995年7月14日至7月29日，奥山在生物研究中心工作。他与Dr.Gombos和Dr.Szalontai一起研究了南极Prymnesiophyte菌株b的亲水性和膜脂的物理相。该菌株生长在5 C时的细胞的光合作用揭示了5 C时的最适温度和膜脂的相变。村田从1996年3月10日到3月29日住在生物研究中心。他与gombos博士和hideg博士一起研究了聚球菌（Synechococcus sp. pcc7002）的耐热性。通过插入突变破坏groel - β基因，降低了该菌株在热休克后的生存能力。然而，破坏并未影响光合活性的热稳定性。这些结果可能表明，热休克蛋白groel - β与热驯化无关。出现在5℃以下。

Dr.Gombos stayd in the National Institute for Basic Biology from September 6th to December 1st, 1995.He, together with Dr.Murata and Dr.Hayashi, studied the photoinhibition of photosystem II at low temperature in Synechocystis sp.PCC 6803.The Synechocystis cells were exposed to various periods of strong light to induce the photoinhibition, which was followed by the recovery of the photosynthetic machinery from the photoinhibited state under dim light at room temperature.It was demonstrated that the photoinhibition was separated into two components ; one was reversible, and the other was irreversible.The reversible component can be explained by the turnover of the D1 protein in the photosystem II complex.The irreversible component had not been well studied, and its molecular mechanism is unknown.In the view point of physiology, the irreversible photoinhibition is deteriorious to the photosynthetic organisms, whereas the reversible photoinhibition provides them with temporal depression of photosynthesis.2.Dr.Okuyama stayd in Biological Research Center from July 14th to July 29th, 1995.He, together with Dr.Gombos and Dr.Szalontai, studied the cryophilicity and the physical phase of membrane lipids of antarctic Haptophyte, Prymnesiophyte strain B.The photosynthesis of the cells of this strain grown 5ﾟC revealed the optimum temperature at 5ﾟC,and the phase transition of the membrane lipids3.Dr.Murata stayd in Biological Research Center from March 10th to March 29th, 1996.He, together with Dr.Gombos and Dr.Hideg, studied the heat tolerance of Synechococcus sp.PCC 7002.The disruption the groEL-beta gene by insertional mutation decreased the viability of this strain after the heat shock.However, the disruption did not affect the heat stability of the photosynthetic activity.These results are likely to suggest that the heat shock protein GroEl-beta is not related to the heat acclimation.appeared below 5ﾟC.