JACK JOHNSON PRT-PRELIMINARY DATA COLLECTION ON P22 BACTERIOPHAGE

这个子项目是许多利用资源的研究子项目之一 由NIH/NCRR资助的中心拨款提供。子项目的主要支持 而子项目的主要调查员可能是由其他来源提供的， 包括其它NIH来源。 列出的子项目总成本可能 代表子项目使用的中心基础设施的估计数量， 而不是由NCRR赠款提供给子项目或子项目工作人员的直接资金。 P22头-尾连接器（也称为门蛋白）是一种连接噬菌体P22的衣壳和尾部的寡聚锥形蛋白。 门蛋白也是将DNA泵入噬菌体头部的机器的组成部分。 寡聚体的每个亚基约为85.9KDa，预期寡聚体具有12倍旋转对称性，总大小约为1.1MDa。 我们已经在各种条件下获得了P22头-尾连接器的晶体，并在旋转阳极X射线发生器上测试了低温条件。 晶体的平均尺寸约为150*50*50 <$m3，具有完美的矩形形态。 我们希望收集一个高分辨率的数据集，并确定复杂的结构，通过使用低温EM低分辨率电子密度图作为起始模型。

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. P22 head-tail connector (also known as portal proteins) is an oligomeric cone-shaped protein that connects the capsid to the tail of bacteriophage P22. The portal protein is also an integral component of the machinery that pumps DNA into the phage head. Each subunit of the oligomer has approximately 85.9KDa and the oligomer is expected to have a 12-fold rotational symmetry with overall size of ~1.1MDa. We have obtained crystals of the P22 head-tail connector under various conditions and tested cryogenic conditions on a rotating anode x-ray generator. The crystals have an average size of ~150*50*50 ¿m3 and a perfect rectangular morphology. We hope to collect a high resolution data set and to determine the structure of the complex by using a cryo-EM low resolution electron density map as a starting model.