Master of Science (MS)
First Advisor's Name
First Advisor's Committee Title
Second Advisor's Name
David C. Chatfield
Third Advisor's Name
Date of Defense
The Ca2+ association to calcium binding proteins (CaBPs) represents an essential step in Ca2+ signal transduction. This study presents a characterization of Ca interactions with two CaBPs, calmodulin and DREAM, using time-resolved photothermal and fluorescence techniques. Calcium binding to the calmodulin C-terminal domain is associated with a volume change of 40 mL mol-1and an enthalpy change of 35 ± 16 kcal mol-1. These parameters are consistent with the Ca2+ triggered exposure of hydrophobic patches on the calmodulin surface. Also, the rate limiting step for Ca2+ binding to calmodulin is the closed-to-open transition of the C-terminal domain that occurs with a lifetime of 400 μs. Unlike calmodulin, DREAM exists in a dynamic equilibrium of two conformations and Ca2+ binding shifts the equilibrium towards a more compact conformation. These data clearly demonstrate that conformational dynamics play a crucial role in the transmission of Ca2+ signals.
Dhulipala, Gangadhar, "Conformational dynamics associated with calcium binding to calcium transducers" (2010). FIU Electronic Theses and Dissertations. 2794.
In Copyright. URI: http://rightsstatements.org/vocab/InC/1.0/
This Item is protected by copyright and/or related rights. You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s).