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Green algae, such as Chlamydomonas reinhardtii , can produce H 2 efficiently using their hydrogenases, but these enzymes are O 2 -sensitive and compete with CO 2 -fixation for electrons. To overcome these limitations, we previously developed an anaerobic, carbon-limited protocol that keeps the Calvin-Benson cycle inactive, and the evolved O 2 is scavenged by an absorbent. The PROTON-GRADIENT REGULATION5 (PGR5)-deficient mutant performs better than the wild type in this system, as it produces at least 2.5-fold more H 2 and maintains its photosynthetic apparatus and hydrogenase activity even at the intensity of sunlight. However, as the pgr5 mutant is known to be sensitive to fluctuating light conditions, it is of paramount interest to determine how it reacts to changes in light intensity during H 2 production. Therefore, we developed an automated system to monitor H 2 production in thin layer cultures under simulated daily light conditions. We found that the pgr5 mutant outperformed the wild type strain by 100 % when light intensity was varied stepwise between 0 and 1000 μmol photons m−2s−1 during the day. Photosynthetic subunits, including PsbA, PSBO, CP47, PetB and PsaA, were fully preserved in the pgr5 mutant, and approximately 29 % of its original hydrogenase activity was sustained after 85 h of H 2 production in simulated daily light conditions. Hence, the pgr5 mutant is a promising candidate for H 2 production under the adverse light conditions that algae may encounter in bioindustry settings. [Display omitted] • An automated thin-cell layer H 2 production system for Chlamydomonas was developed. • The pgr5 mutant outperformed the wild type in simulated daily light conditions. • The photosynthetic and hydrogenase activities of the pgr5 were better preserved. • The pgr5 mutant shows promise for bioindustry settings with adverse conditions. [ABSTRACT FROM AUTHOR]

The installation of multi‐axis goniometers such as the ESRF/EMBL miniKappa goniometer system has allowed the increased use of sample reorientation in macromolecular crystallography. Old and newly appearing data collection methods require precision and accuracy in crystal reorientation. The proper use of such multi‐axis systems has necessitated the development of rapid and easy to perform methods for establishing and evaluating device calibration. A new diffraction‐based method meeting these criteria has been developed for the calibration of the motors responsible for rotational motion. This method takes advantage of crystal symmetry by comparing the orientations of a sample rotated about a given axis and checking that the magnitude of the real rotation fits the calculated angle between these two orientations. Hence, the accuracy and precision of rotational motion can be assessed. This rotation calibration procedure has been performed on several beamlines at the ESRF and other synchrotrons. Some resulting data are presented here for reference. [ABSTRACT FROM AUTHOR]

Hybrid E-cinnamate- and Z-cinnamate-intercalated layered double hydroxides (Mg 2 Al- E- or Z-Cin LDH and Zn 2 Al- E- or Z - Cin LDH) were prepared by the co-precipitation method, and structurally characterised by powder X-ray diffractometry, UV–Vis, FT-IR and 13C CP MAS solid-state NMR spectroscopies to gain further insights on the arrangement of the organic anions in the interlamellar domain. UV light irradiation induced E–Z isomerisation reaction was subsequently attempted in the solid state and in methanolic suspension. Although reaction was observed in the solid state; however, E–Z isomerisation mainly occurred in the slurry phase. The fact that there was no isomerisation when E-Cin was solely adsorbed on the surfaces of pristine LDHs highlights that the reaction took place in the interlayer region. Similar behaviour was observed for the two LDH compositions proving that the LDH structures acted as nanoreactors confining the photoinduced isomerisation. • Intercalation and structural description of cinnamate isomers intercalated in MgAl and ZnAl LDHs. • E-Z isomerisation in the solid state and in slurry. • Isomerisation is followed and verified by various spectroscopic methods (FT-IR, UV–Vis, 13C CP MAS NMR). [ABSTRACT FROM AUTHOR]