Proton gated

Olsen S, Lamothe K, MartiAAnez TJ (2010) Protonic gating of excited-state twisting and charge localization in GFP chromophores a mechanistic hypothesis for reversible photoswitching. J Am Chem Soc 132 1192-1193... 

Chu XP, Miesch J, Johnson M, Root L, Zhu XM, Chen D, Simon RP, Xiong ZG (2002) Proton-gated channels in PC12 cells. J Neurophysiol 87 2555-2561... 

Two histamine-gated chloride chatmd subunits (HisQl and HisCl2, Fig. 29.5.3) expressed in Drosophila eye both contain T at position 2 and are insensitive to PTX and fipronil [58]. In addition, two novel proton-gated chloride channel subunits in this family (pHClA, B and C in Fig. 29.5.3), of unknown function, both contain M at position 2 and are also insensitive to PTX and fipronil [59]. 

Relevance of the Consilient Mechanisms to the Coupling of Electron Transport to Proton Gating/Pumping... 

The focus has been on both aspects of the consilient mechanism (hydrophobic association/ dissociation and elastic force development/ relaxation) involved in the unique domain movement for electron transfer within Complex III. In what follows, the same aspect of hydrophobic association/dissociation of the consilient mechanism is proposed for facilitating proton gating. 

In the context of proton gating, at both the Qo and Qi sites charge formation occurs as the... 

Occupancy Infers Chloride-Induced Proton Gating in a Prokaryotic Homolog of the CIC Chloride Channel. 

B. Yameen, M. Ali, R. Neumarm, W. Ensinger, W. Knoll, and O. Azzaroni. Synthetic proton-gated ion charmels via single solid-state nanochannels modified with responsive polymer brushes. Nangjxtt., 9(7) 2788-2793,2009. 

These experiments and others carried out with protease activation (Moroney, McCarty, 1982) point to a central role for the y subunit in the conversion of CFj to more active states. There are also indications (Moroney et al., 1982) that the structure of the y subunit can influence the proton permeability of the membrane. There may be, then, a direct relationship between the conversion of CFj to an active conformation and the opening of a proton gate in CF. It is of interest to note that oxidized CF in thylakoids is active in ATP synthesis in the light, but not in ATP hydrolysis in the dark, at least for more than a few seconds. Thus, it seems likely that the y subunit of oxidized CF in illuminated thylakoids assumes an active conformation that resembles that of the reduced enzyme. In the dark, the structure of the oxidized and reduced enzymes are likely to be different. 

Proton Gated Emission. Table I provides a partial listing of various PS surface species which have been suggested to be either directly or indirectly related to the luminophore. The pKa provided in this Table is gleamed from the silica gel literature.(22,2i)... 

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