Photo-induced proton gradients for the in vitro investigation of bacterial efflux pumps

We describe an original activity assay for membrane transport that uses the proton motive force-dependent efflux pump MexAB from Pseudomonas aeruginosa. This pump is co-reconstituted into proteoliposomes together with bacteriorhodopsin (BR), a light-activated proton pump. In this system, upon illumination with visible light, the photo-induced proton gradient created by the BR is shown to be coupled to the active transport of substrates through the pump

The Power of Weak Communication

The power of weak communication refers to the ‘silent’ and less visible communicative practices that support social change. These practices are ‘weak’ because they are less ‘noisy’ than the mainstream types of communication sustaining social change campaigns (Tufte, Communication and Social Change: A Citizen Perspective. Cambridge: Polity Press, 2017). They develop organically and are often fragmented, multipolar and based on personal, ‘weak’ relations between individuals and groups. Despite their ‘marginality’, they are powerful and relevant. Yet, they remain undertheorised. The concept offers a tool for legitimising the more local and unmediated communication and the different types of well-being that it enables. It is inspired by feminist scholars and ideas of ‘weak theorizing’, a type of theorising that is more local in its applicability but also more open to possibility (Sedgwick, Touching Feeling: Affect, Pedagogy, Performativity. Durham/London: Duke University Press, 2003).<br