The Mass Spectrometry society of Japan - The 68th Annual Conference on Mass Spectrometry, Japan

Abstract

Oral Sessions

Day 3, May 21(Fri.) 16:25-16:45 Room C (Zoom)

Quantification of Recombinant Protein in E. coli by Single-cell ICP-MS

(Chiba Univ.)
oYu-ki Tanaka, Shunsuke Shimazaki, Yasunori Fukumoto, Yasumitsu Ogra

Single-cell ICP-MS (SC-ICP-MS) technique has been widely adopted to detect a trace or ultratrace amount of element in various kinds of single cell at a level of femtogram or attogram. In this study, we applied SC-ICP-MS to measure elemental contents in a single bacterium, Escherichia coli (E. coli) which is commonly used for obtaining recombinant proteins. E. coli was transformed with the plasmid vector containing red fluorescent protein (mCherry) with Histidine-tag, and then exposed to nickel (Ni) chloride for labeling His-tag with Ni ions. Signal intensity of Ni was measured by SC-ICP-MS to determine the amount of mCherry. The resulting Ni contents were well correlated with the amount of mCherry protein evaluated by SDS-PAGE and following Coomassie Brilliant Blue staining. Our results clearly demonstrate that SC-ICP-MS can be useful technique for evaluating the amount of recombinant protein in a single bacterium cell.