基于蛋白质组学对螺旋藻砷胁迫响应机制的研究

通过研究螺旋藻(Spirulina sp.)在砷离子胁迫下的蛋白质组变化,从蛋白质表达水平解释螺旋藻对砷离子胁迫的响应机理。螺旋藻经过不同浓度砷离子胁迫7 d后,提取蛋白质进行凝胶电泳,并对差异蛋白进行质谱分析。结果表明螺旋藻在2.0 ppm砷酸盐中暴露10 min光合放氧速率降低27.3%,培养24 h后细胞内的金属硫蛋白、叶绿素、类胡萝卜素及藻胆蛋白相对含量均明显降低。蛋白组学共鉴定出75个差异蛋白,其中26个显著上调,49个呈现下调。这些差异蛋白表明砷离子主要通过破坏螺旋藻光合色素蛋白,干扰电子传递过程,导致能量合成受损,使得依赖光合作用产生能量进行的跨膜运动、蛋白质合成等相关过程受到影响;同时,活性氧清除与防御相关蛋白呈现上调,螺旋藻细胞内抗氧化系统被激活。

Proteomic Analysis of Spirulina platensis in Response to Arsenic Stress

Through the study of proteome changes in spirulina(Spirulina sp.)under arsenic ion stress,the response mechanism of spirulina to arsenic ion stress at the level of protein expression is explained.After different concentrations of arsenic ion stress for 7 d,the proteins were extracted for gel electrophoresis and differential proteins were analyzed by mass spectrometry.The results showed that 27.3% reduction in photosynthetic oxygen evolution occurred after 10 min exposing in 2 ppm arsenate,and significant reduction in the relative contents of metallothionein,chlorophyll,carotenoids and phycobiliprotein after cultured for 24 h.Seventy-five proteins were differentially expressed(P<0.05),with 26 significantly induced and 49 declined.These differential proteins indicated that arsenic ion interfered with the electron transfer process via destroying the photosynthetic pigment protein of spirulina,which led to the damage of energy synthesis and thus affected the process of transmembrane movement and protein synthesis depending on photosynthesis to produce energy;meanwhile ROS scavenging and defense-related proteins were up-related,and thus intracellular antioxidant system of spirulina was activated.