Molecular Bases on Bioluminescence and Luminous Behavior Professor

研究了新西兰淡水类软体蜗牛（Latia neritoides）生物发光的分子基础。建立了一种快速、简便的纯化Latia荧光素酶的方法。(1)发现Latia荧光素酶是一种n -连锁糖蛋白，并且在没有任何辅助因子的情况下表现出生物发光活性。尺寸排除色谱分析、SDS-PAGE分析和MALDI-TOF质谱分析表明，该生物发光活性Latia荧光素酶为同六聚体，分子量约为180,000，非生物发光亚基蛋白分子量约为31,000。(2)天然的Latia荧光素虽然有烯醇甲酸基，但甲酰基不是必需的功能，但烯醇乙酸酯也具有生物发光活性，说明Latia的生物发光系统与之前认为的细菌的系统完全不同，Latia荧光素酶也具有酯酶活性。在Latia荧光素酶中形成烯酸阴离子可能是生物发光反应中必不可少的初始事件。(3)从活标本中提取拉蒂亚m-RNA，构建拉蒂亚c-DNA文库。现在荧光素酶c-DNA的克隆正在进行中。

Molecular base on bioluminescence of fresh water limpet-like snails Latia neritoides in New Zealand was investigated. Rapid and convenient method for purification of the Latia luciferase was established. (1) The Latia luciferase was found to be an N-linked glycoprotein, and to exhibit bioluminescence activity without any cofactor. The size exclusion chromatography analysis coupled with SDS-PAGE analysis and MALDI-TOF mass spectrometry indicated that the bioluminescent active Latia luciferase is a homohexamer, whose molecular weight is ca. 180,000 and the molecular weight of the non-bioluminescent subunit protein is ca. 31,000. (2) Although the natural Latia luciferin has an enol formate group, the formyl one was found to be not essential functionality, but enol acetate has also bioluminescence activity, indicating that the bioluminescence system of Latia is completely different from bacteria's ones believed previously and that the Latia luciferase has also an esterase activity. The formation of enolate anion in the Latia luciferase may be essential initial event in the bioluminescence reaction. (3) The Latia m-RNA was extracted from live specimens, from which Latia c-DNA library was constructed. Now cloning of the luciferase c-DNA is in progress.