想要获得高质量蛋白晶体一般需要克服3个难题：1、获得纯度高的，均一的蛋白样品；2，筛选可结晶的条件；3，优化结晶条件，最后获得高质量的单晶；其中，筛选可结晶的条件是获得蛋白质晶体的主要瓶颈之一；

    Jena Biosource品牌中有一系列蛋白结晶研究所要用的试剂和耗材，以下给大家介绍一下Jena里面畅销的蛋白结晶条件筛选试剂盒。

1、JBScreen Basic

JBScreen Basic是基于稀疏矩阵法的蛋白结晶试剂盒，包含了96种筛选条件，整套试剂盒分为4个小规格，每个小规格包含24种条件，24个条件分别密封在螺旋盖试管中，每管10ml,可以随时使用。Jena里面的蛋白结晶筛选试剂盒不包含二甲砷酸盐，用MES进行替代。

二甲砷酸盐，含砷，是有毒物质

1、      致癌物质；

2、      吸入后对人体有害，刺激眼睛和皮肤，长时间接触，可导致肾脏和肝脏受损；

3、      能与自由巯基反应，可以与半胱氨酸硫共价结合，所以存在蛋白构象受到严重影响的风险；

2、 JBScreen Classic

      这个系列是Jena品牌中最初推出的经典的结晶条件试剂盒，在文献中的应用以每年30%的速度增长；这个试剂盒包含了240个筛选条件，涵盖了各种有效沉淀剂和Buffer。整套试剂盒分成了10小规格，每个规格包含了24个条件，如果只想要其中某些条件，是可以单独购买小规格试剂盒的；

         3、JBScreen pentaerythritol

      基于两种新奇的沉淀剂，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结晶条件的筛选。两者都包含一个季戊四醇的支链型高分子。因此他们不同于传统的沉淀剂（如MPD和PEG）。另外，季戊四醇聚合物具有冷冻保护剂的功能，蛋白晶体在这些高浓度的沉淀剂中生长，并能够由晶滴直接冷冻；

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