NOVELTY - Isolated light harvesting entity comprising at least one cellular surface is new, where the surface comprises at least one heterologous light-powered proton pump and a molecular machine, and the molecular machine is directly or indirectly powered by proton motive force, and the heterologous light-powered proton pump provide at least 5% of the proton motive force in the entity.    USE - The isolated light-harvesting entity is useful for: converting biomass into biofuels; controlling drug-resistance of the cell; synthesizing patterns on the surface; and synthesizing composition in the liquid medium (all claimed).    ADVANTAGE - The isolated light-harvesting entity: effectively converts biomass to ethanol; exhibits high tolerance to ethanol and to the toxic by-products present in lignocellulose hydrolysates; and exhibits high sensitivity to environmental factors which regulate cellular proton motive force e.g. light.    DETAILED DESCRIPTION - INDEPENDENT CLAIMS are also included for:    (1) a system (S1) for light-boosted conversion of biomass into biofuels, comprising: the light-collecting entity; a liquid medium, where the medium covers the entity; and a light-source;    (2) method (M1) for light-enhanced conversion of biomass into a biofuel, comprising: depositing the entity on a surface or into a liquid containing a carbon source; and illuminating the entity, resulting in the light-enhanced production of the biofuel, where the fractional conversion enhancement due to illumination is at least 10%, preferably 60-100%;    (3) a system (S2) for effecting light-controlled drug-resistance, comprising: the light-collecting entity, where the entity comprises a light powered proton pump in at least one cellular compartment; and the light-source;    (4) method (M2) for controlling drug-resistance of a cell using light, comprising: depositing the entity onto a surface or into the liquid; and modulating drug transport by the entity by exposing the entity to light of a particular wavelength and/or intensity;    (5) a system (S3) for modifying the surface, comprising: the surface to be modified, where the surface is doped with a chemical that is toxic to unilluminated cells; the light-controlled entity, where the entity is positioned on the surface; the liquid medium, where the medium covers at least a portion of the surface, and the portion includes the entity; a source for emitting light; and a controller for manipulating at least one parameter of the light emitted from the source, where the parameters are intensity, frequency or location with respect to the surface;    (6) method (M3) for synthesizing patterns on the surface, comprising: placing the entity on the surface, covering at least the portion of the surface to be modified and the entity with the liquid medium, and directing at least one action of the entity with a light controller, where the actions are movement, secretion or chemical degradation;    (7) synthesizing (M4) a composition in the liquid medium, comprising: placing the entity in the liquid medium, and directing at least one action of the entity with the light controller; and    (8) method (M5) for enhancing the ability of the isolated light harvesting entity to pump protons in response to illumination, comprising expressing in the light-harvesting entity at least one gene encoding the heterologous light-powered proton pump, where the gene has been modified to promote the formation of a membrane structure having many layers of a membrane in the light-harvesting entity.