Figure 7.

Functional characteristics of the PRs mined from the single-cell Pelagibacter spp. genomes derived by RAGE-Seq. (a) Cell pellets obtained after induction with arabinose and retinal for four E. coli C43 strains harbouring pBAD constructs that contain the putative proteorhodopsin (PR) genes from SCG data of RG1 and RG6, respectively. A pellet from the uninduced C43 strain containing pBAD:Hoch PR is shown as the negative control for comparison. (b) Separation of cell membranes from lysed cell pellets following their application to 10-50% continuous sucrose gradients and centrifugation. (c) Absorption spectra of the detergent-solubilised cell membrane pellets that contain the purified PR.