POWRE: The Calvin Cycle: Evolution and Catalytic Function of Phosphoribulo Kinase in a Marine Chromophyte

卡尔文循环是大气中二氧化碳中的碳转化为碳水化合物的生物过程，在光氧细胞中已经运行了35亿年以上。磷酸腺苷激酶（PRK）作为控制这一生化途径进展的节气门。本课题的目的是探讨PRK在色藻异角藻中的进化起源和催化作用。色植物对全球二氧化碳循环有广泛的贡献，目前还没有关于这类生物PRK的生化信息。一种金棕色的藻——黄斑异藻在世界范围内形成的有毒和有毒藻华，是了解这种生物的生物学对人类如此重要的另一个原因。在该奖项的期限内，研究者的实验室将完成异sigma PRK基因的测序。通过同源性建模研究者将识别残基可能是至关重要的酶的功能；未来将对这些氨基酸进行诱变，以确定它们对功能的影响。此外，还将对酶进行表征。异西格玛PRK基因在酵母中过度表达，产生大量的酶。将开发一种测定PRK活性的方法，并用于测量温度、pH值、抑制剂和底物的影响。这些研究完成后，将形成一个关于PRK在色植物中功能的参考数据库。这是一个power项目。在该奖项支持的休假期间，研究者将有机会学习新技术，并更加熟悉科学公司的文化和需求。新的知识将提高研究者自己的研究和她作为导师的价值和作为大学社区的贡献者。

CattolicoThe Calvin cycle, the biological process by which carbon in atmospheric CO2 is converted into carbohydrate, has functioned in photo-oxygenic cells for over 3.5 billion years. Phosphoribulokinase (PRK) acts as a throttle that governs the progression of this biochemical pathway. The goal of this project is to probe the evolutionary origin and catalytic function of PRK in the chromophytic alga Heterosigma carterae. Chromophytic plants contribute extensively to global CO2 cycling, and currently there is no biochemical information on PRK in this group of organisms. The formation of toxic and noxious algal blooms world-wide by Heterosigma carterae, a golden-brown alga, is another reason that understanding the biology of this organism is so important to mankind.During the term of this award the investigator's laboratory will finish sequencing the gene for Heterosigma PRK. Through homology modeling the investigator will identify residues likely to be crucial for enzymatic function; in the future these amino acids will be mutagenized to determine their effects on function. In addition, the enzyme will be characterized. The Heterosigma PRK gene will be over-expressed in yeast to produce large quantities of the enzyme. An assay for PRK activity will be developed and used in measuring the effects of temperature, pH, inhibitors, and substrates. These studies, when complete, will form a reference database for PRK function in chromophytic plants. This is a POWRE project. During the sabbatical supported by this award, the investigator will have the opportunity to learn new techniques and to become more familiar with the culture and needs of scientific companies. The new knowledge will enhance the investigator's own research and her value as a mentor and as a contributor to the university community.