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Assessing Energy-Dependent Protein Conformational Changes in the TonB System

  • Ray A. Larsen
Protocol
Part of the Methods in Molecular Biology book series (MIMB, volume 1615)

Abstract

Changes in conformation can alter a protein’s vulnerability to proteolysis. Thus, in vivo differential proteinase sensitivity provides a means for identifying conformational changes that mark discrete states in the activity cycle of a protein. The ability to detect a specific conformational state allows for experiments to address specific protein–protein interactions and other physiological components that potentially contribute to the function of the protein. This chapter presents the application of this technique to the TonB-dependent energy transduction system of Gram-negative bacteria, a strategy that has refined our understanding of how the TonB protein is coupled to the ion electrochemical gradient of the cytoplasmic membrane.

Key words

Protein conformation Ion electrochemical gradient Proteinase sensitivity TonB Spheroplast Energy transduction 

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Copyright information

© Springer Science+Business Media LLC 2017

Authors and Affiliations

  1. 1.Department of Biological SciencesBowling Green State UniversityBowling GreenUSA

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