摘要
以南极微藻中的南极硅藻GJ01(Berkeleya rutilansGJ01)为材料,采用分光光度法研究谷胱甘肽的前体氨基酸等因子对谷胱甘肽合成酶的影响,并在少量可供应ATP的南极硅藻GJ01细胞存在的情况下,对其游离谷胱甘肽合成酶合成谷胱甘肽的条件进行优化。结果表明,南极硅藻GJ01谷胱甘肽合成酶的最适温度为10～25℃,最适pH值为7.0;Glu、Cys、Gly的最适浓度分别为24 mmol.L-1、12 mmol.L-18、mmol.L-1。此外Met对谷胱甘肽的合成也有影响,而且南极硅藻GJ01的谷胱甘肽合成酶还具有Mg2+依赖性。正交实验表明,南极硅藻GJ01游离谷胱甘肽合成酶,产生谷胱甘肽的最理想条件为,温度30℃、Cys浓度10 mmol.L-1、Mg2+浓度30 mmol.L-1、pH 7.5。该方法用于工业化生产谷胱甘肽是可行的。
GSH is an essential component of the Asc-glutathione cycle, and its role in the protection of tissues from toxicants and keeping normal redox state of cells has been verified. It is synthesized from its constituent amino acids（Glu, Cys and Gly） by the consecutive actions of 7-blutamylcysteine synthetase and GSH synthetase, both of which are generally named GSH synthesis enzymes. Antarctic microalgae, one of the extreme microorganisms with special characters, is one of the main producers of primary production in marine ecology system of Antarctic pole region. Our former results showed that GSH content and GSH produce ability（GPA） of Antarctic microalgae were higher than those of control（mesophile microalgae）. They have the potential to become new resources of GSH. In this paper, effects of amino acid contributed to GSH on GSH product activity of Antarctic diatom B. rutilans GJ01, isolated from five different phylum growing in Antarctic seawater and Antarctic ice, were studied, as well as the optimization of synthesis condition through free-cell GSH synthesis enzymes and a few B. rutilans GJ01 cells. GSH content,GSH produce ability and protein concentration were assessed using the spectrophotometer methods. It showed that the optimum temperature of GSH synthesis enzymes was 10 - 25 ℃, and optimum pH of that was 7.0. The results also showed that optimum concentrations of amino acid such as Glu, Cys, and Gly were 24 mmol· L^-1, 12 mmol· L^-1 and 8 mmol· L^-1, respectively with only factor test. GPA of B. rutilans GJ01 was dependent on Mg^2 ＋ ,optimum concentration of which was 10 - 20 mmol· L^-1. It was disclosed through the orthogonal test that the primary and second order was respectively Cys, Mg^2＋ , pH and temperature from high to low, and the optimum condition of GSH product was 30 ℃,10 mmol· L^-1 Cys, 30 mmol· L^-1 Mg^2 ＋ and pH 7.5 using the method of free-cell GSH synthesis enzymes of B. rutilans GJ01. These results were also verified by the experiment with higher volume cultural system（5 L）. It was concluded that the optimization of GSH synthesis condition using GSH synthesis enzymes method with the microalga, containing higher GSH, made it possible produce GSH as an industry. [Journal of Fishery Sciences of China,2007,14（5）：829- 835]
出处
《中国水产科学》
CAS
CSCD
北大核心
2007年第5期829-835,共7页
Journal of Fishery Sciences of China
基金
国家自然科学基金资助项目(40206022
40406003)
关键词
南极硅藻GJ01
谷胱甘肽
谷胱甘肽合成酶法
优化条件
Antarctic diatom GJ01
glutathione
glutathione synthesis enzymes method
optimized condition
