<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Kim, Ilsoo</style></author><author><style face="normal" font="default" size="100%">Chakrabarty, Suman</style></author><author><style face="normal" font="default" size="100%">Brzezinski, Peter</style></author><author><style face="normal" font="default" size="100%">Warshel, Arieh</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Modeling gating charge and voltage changes in response to charge separation in membrane proteins</style></title><secondary-title><style face="normal" font="default" size="100%">Proceedings of the National Academy of Sciences of the United States of America</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">bacterial reaction center</style></keyword><keyword><style  face="normal" font="default" size="100%">electrogenicity</style></keyword><keyword><style  face="normal" font="default" size="100%">membrane potential</style></keyword><keyword><style  face="normal" font="default" size="100%">proton/electron transfer</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2014</style></year><pub-dates><date><style  face="normal" font="default" size="100%">AUG</style></date></pub-dates></dates><number><style face="normal" font="default" size="100%">31</style></number><publisher><style face="normal" font="default" size="100%">NATL ACAD SCIENCES</style></publisher><pub-location><style face="normal" font="default" size="100%">2101 CONSTITUTION AVE NW, WASHINGTON, DC 20418 USA</style></pub-location><volume><style face="normal" font="default" size="100%">111</style></volume><pages><style face="normal" font="default" size="100%">11353-11358</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;Measurements of voltage changes in response to charge separation within membrane proteins can offer fundamental information on mechanisms of charge transport and displacement processes. A recent example is provided by studies of cytochrome c oxidase. However, the interpretation of the observed voltage changes in terms of the number of charge equivalents and transfer distances is far from being trivial or unique. Using continuum approaches to describe the voltage generation may involve significant uncertainties and reliable microscopic simulations are not yet available. Here, we attempt to solve this problem by using a coarse-grained model of membrane proteins, which includes an explicit description of the membrane, the electrolytes, and the electrodes. The model evaluates the gating charges and the electrode potentials (c.f. measured voltage) upon charge transfer within the protein. The accuracy of the model is evaluated by a comparison of measured voltage changes associated with electron and proton transfer in bacterial photosynthetic reaction centers to those calculated using our coarse-grained model. The calculations reproduce the experimental observations and thus indicate that the method is of general use. Interestingly, it is found that charge-separation processes with different spatial directions (but the same distance perpendicular to the membrane) can give similar observed voltage changes, which indicates that caution should be exercised when using simplified interpretation of the relationship between charge displacement and voltage changes.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">31</style></issue><custom3><style face="normal" font="default" size="100%">Foreign</style></custom3><custom4><style face="normal" font="default" size="100%">5.98</style></custom4></record></records></xml>