Journal
PEERJ
Volume 1, Issue -, Pages -Publisher
PEERJ INC
DOI: 10.7717/peerj.16
Keywords
Ion channel; Ion selectivity; Molecular dynamics; Sodium channel; Action potential; Bacterial channel; Calcium channel; Simulation
Categories
Funding
- Merit Allocation Scheme of the NCI facility at the ANU
Ask authors/readers for more resources
The recent publication of a number of high resolution bacterial voltage-gated sodium channel structures has opened the door for the mechanisms employed by these channels to distinguish between ions to be elucidated. The way these channels select between Na+ and K+ has been investigated in computational studies, but the selectivity for Na+ over Ca2+ has not yet been studied in this way. Here we use molecular dynamics simulations to calculate the energetics of Na+ and Ca2+ transport through the channel. Single ion profiles show that Ca2+ experiences a large barrier midway through the selectivity filter that is not seen by Na+. This barrier is caused by the need for Ca2+ to partly dehydrate to pass through this region and the lack of compensating interactions with the protein. Multi-ion profiles show that ions can pass each other in the channel, which is why the presence of Ca2+ does not block Na+ conduction despite binding more strongly in the pore.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available