A Possible Correlation between Fluctuations and Function of a Membrane Protein
It is well known that proteins are not static structures but dynamic entities which undergo conformational transitions in fulfillment of their catalytic function. The characteristic times of such transitions are given by the turnover numbers of the proteins and range from below milliseconds to seconds. In addition to these large and slow conformational transitions, proteins undergo small and fast conformational fluctuations, their characteristic times extending from picoseconds to microseconds. This implies that each of the few conformational states consists of a large number of substates and transitions between substates occur frequently. The existence of substates and fluctuations has been demonstrated by a number of different techniques1.
KeywordsConformational State Rotational Diffusion Transport Cycle Lactose Permease Slow Fluctuation
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