Structural model of the voltage-gated potassium channel Kv1.1 and molecular docking of Tc1 toxin from Tityus cambridgei to KcsA and Kv1.1
نویسندگان
چکیده
In this study, structural model of the pore loop region of the voltage-gated potassium channel Kv1.1 was constructed based on the crystallographic structure of KcsA. Subsequently, molecular docking experiments of Tc1 towards KcsA as well as Kv1.1 were performed. Tc1 forms the most stable complexes with these two channels when the side chain of K14 occupies the first Kþ binding site. Tc1 binds preferentially towards Kv1.1 than KcsA due to the stronger electrostatic and hydrophobic interactions. Furthermore, surface complementarity of the outer vestibules of the channel to the Tc1 spatial conformations also plays an important role in stabilizing these Tc1/channel complexes. 2003 Elsevier B.V. All rights reserved.
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