Efficiency and process development for microbial biomass production using oxic bioelectrosynthesis.

Autotrophic microbial electrosynthesis (MES) processes are mainly based on organisms that rely on carbon dioxide (CO) as an electron acceptor and typically have low biomass yields. However, there are few data on the process and efficiencies of oxic MES (OMES). In this study, we used the knallgas bacterium Kyrpidia spormannii to investigate biomass formation and energy efficiency of cathode-dependent growth.

How Comparable are Microbial Electrochemical Systems around the Globe? An Electrochemical and Microbiological Cross-Laboratory Study.

Invited for this month's cover is the collaborative work among Univ. of Milano-Bicocca, Ricerca sul Sistema Energetico S.p.

How Comparable are Microbial Electrochemical Systems around the Globe? An Electrochemical and Microbiological Cross-Laboratory Study.

A cross-laboratory study on microbial fuel cells (MFC) which involved different institutions around the world is presented. The study aims to assess the development of autochthone microbial pools enriched from domestic wastewater, cultivated in identical single-chamber MFCs, operated in the same way, thereby approaching the idea of developing common standards for MFCs. The MFCs are inoculated with domestic wastewater in different geographic locations.

Monitoring stratification of anode biofilms in bioelectrochemical laminar flow reactors using flow cytometry.

A laminar flow bioelectrochemical systems (BES) was designed and benchmarked using microbial anodes dominated with spp. The reactor architecture was based on modeled flow fields, the resulting structure was 3D printed and used for BES manufacturing. Stratification of the substrate availability within the reactor channels led to heterogeneous biomass distribution, with the maximum biomass found mainly in the initial/middle channels.

Response-Surface-Optimized and Scaled-Up Microbial Electrosynthesis of Chiral Alcohols.

A variety of enzymes can be easily incorporated and overexpressed within Escherichia coli cells by plasmids, making it an ideal chassis for bioelectrosynthesis. It has recently been demonstrated that microbial electrosynthesis (MES) of chiral alcohols is possible by using genetically modified E. coli with plasmid-incorporated and overexpressed enzymes and methyl viologen as mediator for electron transfer.

Crystal Structure of Dihydro-Heme d Dehydrogenase NirN from Pseudomonas aeruginosa Reveals Amino Acid Residues Essential for Catalysis.

Many bacteria can switch from oxygen to nitrogen oxides, such as nitrate or nitrite, as terminal electron acceptors in their respiratory chain. This process is called "denitrification" and enables biofilm formation of the opportunistic human pathogen Pseudomonas aeruginosa, making it more resilient to antibiotics and highly adaptable to different habitats. The reduction of nitrite to nitric oxide is a crucial step during denitrification.

Resting Escherichia coli as Chassis for Microbial Electrosynthesis: Production of Chiral Alcohols.

Chiral alcohols constitute important building blocks that can be produced enantioselectively by using nicotinamide adenine dinucleotide (phosphate) [NAD(P)H]-dependent oxidoreductases. For NAD(P)H regeneration, electricity delivers the cheapest reduction equivalents. Enzymatic electrosynthesis suffers from cofactor and enzyme instability, whereas microbial electrosynthesis (MES) exploits whole cells.

Reactors for Microbial Electrobiotechnology.

From the first electromicrobial experiment to a sophisticated microbial electrochemical process - it all takes place in a reactor. Whereas the reactor design and materials used strongly influence the obtained results, there are no common platforms for MES reactors. This is a critical convention gap, as cross-comparison and benchmarking among MES as well as MES vs.

Paving the way for bioelectrotechnology: Integrating electrochemistry into bioreactors.

The reactor systems used for microbial electrosynthesis, i.e. bioelectrochemical systems for achieving bioproduction so far reported in literature are relatively small in scale and highly diverse in their architecture and modes of operation.

A framework for modeling electroactive microbial biofilms performing direct electron transfer.

A modeling platform for microbial electrodes based on electroactive microbial biofilms performing direct electron transfer (DET) is presented. Microbial catabolism and anabolism were coupled with intracellular and extracellular electron transfer, leading to biofilm growth and current generation. The model includes homogeneous electron transfer from cells to a conductive biofilm component, biofilm matrix conduction, and heterogeneous electron transfer to the electrode.

Electrifying white biotechnology: engineering and economic potential of electricity-driven bio-production.

Invited for the cover of this issue are the groups of Falk Harnisch at the Helmholtz Centre for Environmental Research (Germany) and his collaboration partners at The University of Queensland (Australia). The image depicts their vision of the world, if "electrification" of white biotechnology comes true. The Concept itself is available at 10.

Electrifying white biotechnology: engineering and economic potential of electricity-driven bio-production.

The production of fuels and chemicals by electricity-driven bio-production (i.e., using electric energy to drive biosynthesis) holds great promises.

Acoustic detection of cell adhesion on a quartz crystal microbalance.

An acoustic quartz crystal microbalance (QCM) was used to signal and follow the cell‑adhesion process of epithelial cells [human embryonic kidney(HEK) 293T and cervical cancer (HeLa) and fibroblasts [African Green Monkey kidney cells (COS-7)] onto gold surfaces. Cells were applied on the sensor and grown under serum-free and serum-supplemented culture media. The sensor resonance frequency (Δf) and motional resistance (ΔR) variations were measured during cell growth to monitor cell adhesion processes.