The colonization of land by plants was a key event in the evolution of life. Here we report the draft genome sequence of the filamentous terrestrial alga Klebsormidium flaccidum (Division Charophyta, Order Klebsormidiales) to elucidate the early transition step from aquatic algae to land plants. Comparison of the genome sequence with that of other algae and land plants demonstrate that K. flaccidum acquired many genes specific to land plants. We demonstrate that K. flaccidum indeed produces several plant hormones and homologues of some of the signalling intermediates required for hormone actions in higher plants. The K. flaccidum genome also encodes a primitive system to protect against the harmful effects of high-intensity light. The presence of these plant-related systems in K. flaccidum suggests that, during evolution, this alga acquired the fundamental machinery required for adaptation to terrestrial environments.

The present article describes the hydrogen production from an aqueous medium over amino-functionalized Ti(IV) metal–organic framework (Ti-MOF-NH2) under visible-light irradiation. Ti-MOF-NH2, which employs 2-amino-benzenedicarboxylic acid as an organic linker, has been synthesized by a facile solvothermal method. Pt nanoparticles as cocatalysts are then deposited onto Ti-MOF-NH2 via a photodeposition process (Pt/Ti-MOF-NH2). The XRD and N2 adsorption measurements reveal the successful formation of a MOF framework structure and its remaining structure after deposition of Pt nanoparticles. The observable visible-light absorption up to ∼500 nm can be seen in the DRUV–vis spectrum of Ti-MOF-NH2, which is associated with the chromophore in the organic linker. Ti-MOF-NH2 and Pt/Ti-MOF-NH2 exhibit efficient photocatalytic activities for hydrogen production from an aqueous solution containing triethanolamine as a sacrificial electron donor under visible-light irradiation. The longest wavelength available for the reaction is 500 nm. The results obtained from wavelength-dependent photocatalytic tests and photocurrent measurements as well as in situ ESR measurements demonstrate that the reaction proceeds through the light absorption by its organic linker and the following electron transfer to the catalytically active titanium-oxo cluster.

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