鱼腥藻PCC7120藻红蓝蛋白α亚基体内重组研究  

Biosynthesis of a Fluorescent Cyanobacterial Phycoerythrocyanin Holo-α Subunit in Escherichia coli

作　　者：滕吟[1] 周明[1] 陈芳[1] 赵开弘[1] 

机构地区：[1]华中科技大学环境科学与工程学院,武汉430074

出　　处：《武汉植物学研究》2006年第6期493-497,共5页Journal of Wuhan Botanical Research

基　　金：国家自然科学基金资助项目(30540070)

摘　　要：为了研究藻红蓝蛋白α亚基的生物合成途径,通过构建相容的4种重组质粒pETDuetp-ecA、pCOLADuet-pecE、pCDFDuetp-ecF和pACYCDuet-ho1-pcyA,将裂合酶基因pecE和pecF、血红素氧化酶基因ho1、藻蓝胆素合成酶基因pcyA和脱辅基藻红蓝蛋白α亚基基因pecA共同转入大肠杆菌BL21(DE3),通过色素蛋白锌电泳和光谱检测表明产生了生物活性的PecA-PCB。结果表明生成的色素藻胆蛋白具有藻红蓝蛋白α-亚基所特有的光谱性质和可逆光致变色性质。而在裂合酶基因pecE和pecF不转入大肠杆菌的情况下,大肠杆菌内只有0.1%的PecA-PCB产生。以上研究对藻胆蛋白生物构建具有重要意义。The entire pathway for the synthesis of a fluorescent holophycobiliprotein subunit from a photosynthetic cyanobacterium （Anabaena sp. PCC7120） was reconstituted in Escherichia coli. Cyanobacterial genes for enzymes hol and pcyA were expressed from a plasmid pACYCDuet-hol-pcyA. Genes for the apoprotein （Phycoerythrocyanin ct subunit ;pecA） were expressed on a second plasmid pETDuet-pecA. Genes for the heterodimeric lyase （pecE and pecF） that catalyzes chromophore attachment were expressed on a third plasmid pCOLADuet-pecE and a fourth plasmid pCDrDuet-pecF. Upon induction ,recombinant E. coli used the cellular pool of heme to produce holo-PecA with spectroscopic properties qualitatively and quantitatively similar to those of the same protein produced endogenously in cyanobacteria. However, unlike the other biliproteins, isolated PEC shows a pronounced reversible photochemistry, which has been related to the α-subunit （α-PEC）. About 0. 1% of the apo-PecA was converted to holo-PecA-PCB in a similarly engineered E. coli strain that lacks pecE and pecF.

关 键 词：藻红蓝蛋白 PECA pecE pecF 体内重组 

分 类 号：Q784[生物学—分子生物学]