Bioinspired Nanochitin-Based Porous Constructs for Light-Driven Whole-Cell Biotransformations.

Solid-state photosynthetic cell factories (SSPCFs) are a new production concept that leverages the innate photosynthetic abilities of microbes to drive the production of valuable chemicals. It addresses practical challenges such as high energy and water demand and improper light distribution associated with suspension-based culturing; however, these systems often face significant challenges related to mass transfer. The approach focuses on overcoming these limitations by carefully engineering the microstructure of the immobilization matrix through freeze-induced assembly of nanochitin building blocks.

Characterization of the oxygen-tolerant formate dehydrogenase from .

Fixation of CO into the organic compound formate by formate dehydrogenases (FDHs) is regarded as the oldest autotrophic process on Earth. It has been proposed that an FDH-dependent CO fixation module could support CO assimilation even in photoautotrophic organisms. In the present study, we characterized FDH from (FDH) due to its ability to reduce CO under aerobic conditions.

Towards high atom economy in whole-cell redox biocatalysis: up-scaling light-driven cyanobacterial ene-reductions in a flat panel photobioreactor.

Light-driven biotransformations in recombinant cyanobacteria benefit from the atom-efficient regeneration of reaction equivalents like NADPH from water and light by oxygenic photosynthesis. The self-shading of photosynthetic cells throughout the reaction volume, along with the need for extended light paths, limits adequate light supply and significantly restricts the potential for upscaling. Here, we present a flat panel photobioreactor (1 cm optical path length) as a scalable system to provide efficient illumination at high cell densities.

A Clickable Photosystem I, Ferredoxin, and Ferredoxin NADP Reductase Fusion System for Light-Driven NADPH Regeneration.

Photosynthetic organisms like plants, algae, and cyanobacteria use light for the regeneration of dihydronicotinamide dinucleotide phosphate (NADPH). The process starts with the light-driven oxidation of water by photosystem II (PSII) and the released electrons are transferred via the cytochrome b f complex towards photosystem I (PSI). This membrane protein complex is responsible for the light-driven reduction of the soluble electron mediator ferredoxin (Fd), which passes the electrons to ferredoxin NADP reductase (FNR).

Photosynthesis re-wired on the pico-second timescale.

Photosystems II and I (PSII, PSI) are the reaction centre-containing complexes driving the light reactions of photosynthesis; PSII performs light-driven water oxidation and PSI further photo-energizes harvested electrons. The impressive efficiencies of the photosystems have motivated extensive biological, artificial and biohybrid approaches to 're-wire' photosynthesis for higher biomass-conversion efficiencies and new reaction pathways, such as H evolution or CO fixation. Previous approaches focused on charge extraction at terminal electron acceptors of the photosystems.