{"id":3253,"date":"2023-02-17T07:09:33","date_gmt":"2023-02-17T07:09:33","guid":{"rendered":"http:\/\/ionchanneltargets.com\/resource_library\/2016-mechano-pharmacological-characterization-of-cardiomyocytes-derived-from-human-induced-pluripotent-stem-cells\/"},"modified":"2023-02-17T07:09:33","modified_gmt":"2023-02-17T07:09:33","slug":"2002-photocurrents-generated-by-bacteriorhodopsin-adsorbed-on-thiol-lipid-bilayers-supported-by-mercury","status":"publish","type":"resource_library","link":"https:\/\/nanion.com\/zh-hans\/resource_library\/2002-photocurrents-generated-by-bacteriorhodopsin-adsorbed-on-thiol-lipid-bilayers-supported-by-mercury\/","title":{"rendered":"2002 &#8211; Photocurrents Generated by Bacteriorhodopsin Adsorbed on Thiol\/Lipid Bilayers Supported by Mercury"},"content":{"rendered":"<p>The kinetics of light-driven proton transport by bacteriorhodopsin (bR) were investigated over a broad pH range upon adsorbing purple membrane (PM) fragments on a mercury-supported mixed alkanethiol\/phospholipid bilayer. The light-on and light-off capacitive photocurrents were measured under short-circuit conditions in the absence of photoartifacts. Using dioleoylphosphatidylcholine as the lipid monolayer, a bell-shaped curve of the peak current versus pH, with a maximum in the proximity of 6, was obtained. The analysis of the biphasic decay kinetics of the light-on and light-off currents allows an estimate of the pKa\u00a0values for the steps releasing protons to, and taking up protons from, the bathing solution. In particular, the pKa\u00a0values obtained from the light-off current (pK1\u00a0= 3.5, pK2\u00a0= 5.3, pK3\u00a0= 7.5, and pK4\u00a0= 9.0) suggest a mechanism similar to that proposed by Balashov et al. for dark adaptation, albeit in the opposite direction (Balashov, S. P.; Imasheva, E. S.; Govindjee, R.; Sheves, M.; Ebrey, T. G. Biophys. J. 1996, 70, 473). The time dependence of the light-on and light-off currents in the proximity of pH 6 is interpreted on the basis of both a simple equivalent circuit and a kinetic model making use of spectroscopic data available in the literature. When using dioleoylphosphatidylserine (DOPS) as the lipid monolayer, an inversion in the sign of both light-on and light-off currents, as well as a change in their shape and magnitude, was observed by increasing the pH above 9 and then, at all pH values from 9 to 1, by subsequently decreasing the pH on the same mercury-supported mixed alkanethiol\/DOPS bilayer. The normal situation was restored only by adding sodium azide. This inversion in current and the notable hysteresis observed under these conditions are critically discussed.<\/p>\n","protected":false},"featured_media":0,"template":"","products_tags":[36],"resource_type":[75],"application_areas":[108],"therapeutic_areas":[],"target_categories":[60],"target_families":[369],"targets":[209],"resource_keyword":[],"class_list":["post-3253","resource_library","type-resource_library","status-publish","hentry","products_tags-surfe2r-n1","resource_type-publication","application_areas-transporters","target_categories-transporters","target_families-light-driven","targets-bacteriorhodopsin"],"acf":[],"_links":{"self":[{"href":"https:\/\/nanion.com\/zh-hans\/wp-json\/wp\/v2\/resource_library\/3253","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/nanion.com\/zh-hans\/wp-json\/wp\/v2\/resource_library"}],"about":[{"href":"https:\/\/nanion.com\/zh-hans\/wp-json\/wp\/v2\/types\/resource_library"}],"wp:attachment":[{"href":"https:\/\/nanion.com\/zh-hans\/wp-json\/wp\/v2\/media?parent=3253"}],"wp:term":[{"taxonomy":"products_tags","embeddable":true,"href":"https:\/\/nanion.com\/zh-hans\/wp-json\/wp\/v2\/products_tags?post=3253"},{"taxonomy":"resource_type","embeddable":true,"href":"https:\/\/nanion.com\/zh-hans\/wp-json\/wp\/v2\/resource_type?post=3253"},{"taxonomy":"application_areas","embeddable":true,"href":"https:\/\/nanion.com\/zh-hans\/wp-json\/wp\/v2\/application_areas?post=3253"},{"taxonomy":"therapeutic_areas","embeddable":true,"href":"https:\/\/nanion.com\/zh-hans\/wp-json\/wp\/v2\/therapeutic_areas?post=3253"},{"taxonomy":"target_categories","embeddable":true,"href":"https:\/\/nanion.com\/zh-hans\/wp-json\/wp\/v2\/target_categories?post=3253"},{"taxonomy":"target_families","embeddable":true,"href":"https:\/\/nanion.com\/zh-hans\/wp-json\/wp\/v2\/target_families?post=3253"},{"taxonomy":"targets","embeddable":true,"href":"https:\/\/nanion.com\/zh-hans\/wp-json\/wp\/v2\/targets?post=3253"},{"taxonomy":"resource_keyword","embeddable":true,"href":"https:\/\/nanion.com\/zh-hans\/wp-json\/wp\/v2\/resource_keyword?post=3253"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}