Open AccessEnergy‐Dependent Changes in Membranes of Rhodospirillum rubrum Chromatophores as Measured by 8‐Anilino‐naphthalene‐1‐sulfonic Acid
Author(s) -
Vainio Harri,
Baltscheffsky Margareta,
Baltscheffsky Herrick,
Azzi Angelo
Publication year - 1972
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1972.tb02098.x
Subject(s) - rhodospirillum rubrum , oligomycin , valinomycin , fluorescence , nigericin , chemistry , gramicidin , chaotropic agent , ionophore , membrane , chromatophore , photophosphorylation , antimycin a , photochemistry , biophysics , biochemistry , biology , electron transport chain , atpase , physics , quantum mechanics , fishery , enzyme , chloroplast , gene
1 Rhodospirillum rubrum chromatophores enhance the fluorescence of 8‐anilino‐naphthalene‐1‐sulfonic acid (ANS). Energization of the chromatophore membrane by ATP, PP i , or succinate produces a fluorescence increase in ANS; PP i is the most potent in this respect. 2 It was possible to inhibit the fluorescence increase due to ATP, PP i , and succinate by uncouplers; namely, gramicidin, valinomycin, and tetraphenylboron. The uncouplers did not, however, affect the non‐energy‐dependent ANS fluorescence. 3 It was possible to inhibit the increase in ANS fluorescence due to ATP by oligomycin, whereas the PP i ‐induced ANS fluorescence increase was even slightly stimulated in the presence of oligomycin. 4 The antibiotic dio‐9 was able to inhibit the fluorescence increase due to both ATP and PP i , without, however, affecting the non‐energy‐dependent ANS fluorescence. 5 Chaotropic agents such as KSCN and urea, and the detergent deoxycholate all inhibited the PP i ‐induced membrane energization, as detected by ANS fluorescence.