莱茵藻胞外碳酸酐酶分子定位与活性诱导

胞外碳酸酐酶是藻类CCM机制和光合作用的一个重要组分 ,藻类从高CO2 转入低CO2 浓度培养时可诱导出胞外碳酸酐酶。应用金标免疫分子定位和pH调节对胞外碳酸酐酶分子定位和CO2 诱导机制进行研究 ,结果表明 :胞外碳酸酐酶主要分布于胞壁空间 (细胞质膜与细胞壁之间 ) ,且细胞壁上也有较多分布 ,细胞壁外分布较少。说明胞外碳酸酐酶能从胞壁空间穿过细胞壁。通过CO2 诱导和pH调节(升高 ) ,均可提高碳酸酐酶活性 ,且pH提高幅度越大 ,胞外碳酸酐酶活性也越大 ,说明胞外碳酸酐酶的CO2 诱导与pH调节有一定关系

Molecular Localization and Activity Inducement of Perplasmic Carbonic Anhydrase in Chlamydomonus reinhardtii

Periplasmic carbonic anhydrase (pCA) is a key enzyme in CCM and the photosynthetic carbon fixation of algae. When algae in high CO 2 concentration are transferred to low CO 2 concentration condition, perplasmic carbonic anhydrase is induced in them. We studied the pCA molecular localization and activity inducement, using the gold immunolocalization technology and strict pH regulation. The results showed that pCAs were mainly located in the periplasmic space (between cell wall and plasmatic membrane), with some pCAs on the cell walls and a little PCAs outside cell walls, implying that pCAs could penetrate from periplasmic space into outside of cell walls. With both CO 2 inducement and strict pH regulation, pCA activity was increased. The higher the pH increased, the higher the pCA activity became, indicating that the CO 2 inducement of pCA was closely related to the regulation of pH.