Tandem gene amplification restores photosystem II accumulation in cytochrome b mutants of cyanobacteria.

Cytochrome (Cyt) b is a key component of the photosystem II complex (PSII) that is essential for its proper functioning and assembly. Site-directed mutants of the model cyanobacterium Synechocystis sp. PCC6803 with mutated heme axial ligands of Cyt b have little PSII and are therefore unable to grow photoautotrophically.

New approaches to bridge nerve gaps: development of a novel drug-delivering nerve conduit.

Contemporary bridging techniques for repairing nerve gaps caused by trauma require autologous nerve grafts, which are difficult to harvest and handle and result in significant donor site deficit. Several nerve conduits with axon growth-enhancing potential have been proposed, developed and tested over the past fifteen years. In this work, prototypes of a nerve conduit designed to bridge large nerve gaps (≥10mm) end-to-end were incorporated with concentric drug reservoirs for constant and controlled drug delivery to enhance axon growth.