想要獲得高質量蛋白晶體一般需要克服3個難題：1、獲得純度高的，均一的蛋白樣品；2，篩選可結晶的條件；3，優化結晶條件，最后獲得高質量的單晶；其中，篩選可結晶的條件是獲得蛋白質晶體的主要瓶頸之一；

    Jena Biosource品牌中有一系列蛋白結晶研究所要用的試劑和耗材，以下給大家介紹一下Jena里面暢銷的蛋白結晶條件篩選試劑盒。

1、JBScreen Basic

JBScreen Basic是基于稀疏矩陣法的蛋白結晶試劑盒，包含了96種篩選條件，整套試劑盒分為4個小規格，每個小規格包含24種條件，24個條件分別密封在螺旋蓋試管中，每管10ml,可以隨時使用。Jena里面的蛋白結晶篩選試劑盒不包含二甲砷酸鹽，用MES進行替代。

二甲砷酸鹽，含砷，是有毒物質

1、      致癌物質；

2、      吸入后對人體有害，刺激眼睛和皮膚，長時間接觸，可導致腎臟和肝臟受損；

3、      能與自由巰基反應，可以與半胱氨酸硫共價結合，所以存在蛋白構象受到嚴重影響的風險；

2、 JBScreen Classic

      這個系列是Jena品牌中最初推出的經典的結晶條件試劑盒，在文獻中的應用以每年30%的速度增長；這個試劑盒包含了240個篩選條件，涵蓋了各種有效沉淀劑和Buffer。整套試劑盒分成了10小規格，每個規格包含了24個條件，如果只想要其中某些條件，是可以單獨購買小規格試劑盒的；

         3、JBScreen pentaerythritol

      基于兩種新奇的沉淀劑，季戊四醇丙氧基化物和季戊四醇乙基化物，用于生物大分子最初結晶條件的篩選。兩者都包含一個季戊四醇的支鏈型高分子。因此他們不同于傳統的沉淀劑（如MPD和PEG）。另外，季戊四醇聚合物具有冷凍保護劑的功能，蛋白晶體在這些高濃度的沉淀劑中生長，并能夠由晶滴直接冷凍；

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