Measuring the stoichiometry of functional PspA complexes in living bacterial cells by single molecule photobleaching

摘要

We report a general method based on wide-field fluorescence imaging of single molecule photobleaching and the Chung-Kennedy algorithm to measure the stoichiometry of functional protein complexes in living bacterial cells. Proteins often function as multimeric complexes in cellular processes such as signal transduction and ion transport. Many well-established techniques exist to determine the structure and composition of protein complexes in their isolated forms in vitro, yet it is challenging to measure the stoichiometry of functional complexes in living cells.