2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/220122We present measurements of the fluctuation spectrum of giant vesicles containing bacteriorhodopsin (BR) pumps using video-microscopy. When the pumps are activated, we observe a significant increase of the fluctuations in the low wavevector region, which we interpret as due to a lowering of the effective tension of the membrane.4 pages, 2 figuresSoft Condensed MatterOther Condensed Mattertext