（stimulus）時(shí),，酶的活性增加（output）。（圖片來源：Benkovic lab, Penn State）
美國科學(xué)家近日發(fā)現(xiàn)了一種新方法,，能夠利用光控制催化生化反應(yīng)的某種蛋白活性,。研究人員稱，這是首次成功利用光來控制一種蛋白的活性,，將來可能具有多種應(yīng)用,，比如用來關(guān)閉細(xì)胞中致病蛋白的活性等。相關(guān)論文發(fā)表在10月17日的《科學(xué)》（Science）雜志上,。
美國德州大學(xué)西南醫(yī)學(xué)中心的Rama Ranganathan和同事,，通過將來自燕麥的光覺蛋白插入來自大腸桿菌的催化生化反應(yīng)的酶，創(chuàng)造出了一種雜種蛋白,。研究人員發(fā)現(xiàn),，向這個(gè)光覺蛋白照射光可操縱酶的活性。論文主要作者之一,、美國賓夕法尼亞州立大學(xué)化學(xué)系的Stephen Benkovic說：“這一技術(shù)就像光開關(guān),，當(dāng)我們向光覺蛋白照射光時(shí)，酶的活性增加,；當(dāng)關(guān)閉光時(shí),，酶的活性降低。”
研究人員表示,，在設(shè)計(jì)雜種蛋白的時(shí)候,，有幾個(gè)重要的因素需要考慮。一個(gè)是蛋白的正確構(gòu)象,，錯(cuò)誤構(gòu)象將會(huì)使蛋白無法對(duì)光作出反應(yīng),；一個(gè)是光覺蛋白插入酶的特定位點(diǎn)，位點(diǎn)錯(cuò)誤同樣會(huì)使光開關(guān)無法起作用,。
研究小組未來將會(huì)研究由光觸發(fā)的信號(hào)如何從光覺蛋白向酶傳輸,。Benkovic說：“這一過程的作用機(jī)制尚不清楚，目前來看,，其效果也較小,。不過我們計(jì)劃優(yōu)化這一技術(shù),，看看是否能夠以另一種方式利用光，來調(diào)節(jié)酶的活性,。”（生物谷Bioon.com）
生物谷推薦原始出處：
Science,，Vol. 322. no. 5900, pp. 438 – 442，Jeeyeon Lee,，Rama Ranganathan
Surface Sites for Engineering Allosteric Control in Proteins
Jeeyeon Lee,1* Madhusudan Natarajan,2* Vishal C. Nashine,1 Michael Socolich,2 Tina Vo,2 William P. Russ,2 Stephen J. Benkovic,1 Rama Ranganathan2
Statistical analyses of protein families reveal networks of coevolving amino acids that functionally link distantly positioned functional surfaces. Such linkages suggest a concept for engineering allosteric control into proteins: The intramolecular networks of two proteins could be joined across their surface sites such that the activity of one protein might control the activity of the other. We tested this idea by creating PAS-DHFR, a designed chimeric protein that connects a light-sensing signaling domain from a plant member of the Per/Arnt/Sim (PAS) family of proteins with Escherichia coli dihydrofolate reductase (DHFR). With no optimization, PAS-DHFR exhibited light-dependent catalytic activity that depended on the site of connection and on known signaling mechanisms in both proteins. PAS-DHFR serves as a proof of concept for engineering regulatory activities into proteins through interface design at conserved allosteric sites.
1 Department of Chemistry, Pennsylvania State University, University Park, PA 16802, USA.
2 Green Center for Systems Biology and Department of Pharmacology, University of Texas Southwestern Medical Center, Dallas, TX 75390, USA.
