He Xiang - BfrB - Systematic Identification of Mycobacterium tuberculosis Effectors Reveals that BfrB Suppresses Innate Immunity

To identify the macrophage binding partner of Mtb BfrB, we selected and purified BfrB tagged with GST, and incubated it with THP-1 lysates before performing GST Pullodwn. Then the eluted protein were examined by sliver stain. Using mass spectrometry, we identified a protein with an apparent molecular mass of 28 KDa as RPS3, an essential subunit of NF-κB involved in the regulation of key genes in rapid cellular activation response.

为鉴定结核分枝杆菌（Mycobacterium tuberculosis, Mtb）BfrB的巨噬细胞结合伴侣，我们选取并纯化了带有谷胱甘肽S-转移酶（Glutathione S-transferase, GST）标签的BfrB蛋白，将其与THP-1细胞裂解液共孵育后开展GST下拉实验。随后通过银染对洗脱得到的蛋白进行检测，借助质谱分析将表观分子量为28 kDa的蛋白鉴定为RPS3——该蛋白是核因子κB（Nuclear Factor-κB, NF-κB）的必需亚基，参与调控细胞快速活化应答相关的关键基因。