Discovering nanomachines within living organisms: Cytochromes P450 unleashed as living soft robots

Phys.org  August 7, 2023 An international team of researchers (Israel, India) addressed the difference between regular 3D matter and the nanomachines in ‘living matters’ (e.g., the CYP450 enzymes), which oxidize an array of essential substrate molecules. Molecular dynamics simulations revealed that, unlike 3D materials, CYP450s are 4D nanomachines, in which the fourth dimension was a sensing mechanism whereby the protein responds to an initial stimulus of substrate entrance and performs an autonomous chain of events (the catalytic cycle), which leads to substrate oxidation. They found that stimulus was the binding of a substrate molecule that eventually underwent oxidation in a […]

Bacteria as blacksmiths – new method to assemble unconventional materials

Nanowerk  July 27, 2023 When in equilibrium, thermal forces agitate molecules, which then diffuse, collide, and bind to form materials. However, the space of accessible structures in which micron-scale particles can be organized by thermal forces is limited, owing to the slow dynamics and metastable states. Active agents in a passive fluid generate forces and flows, forming a bath with active fluctuations. Two unanswered questions are whether those active agents can drive the assembly of passive components into unconventional states and which material properties they will exhibit. Researchers in Austria showed that passive, sticky beads immersed in a bath of […]

Intelligent rubber materials

Nanowerk  July 18, 2023 Researchers in Germany have developed intelligent humidity-programmed hydrogel patches with high stretchability and tunable water-uptake and -release by copolymerization and crosslinking of N-isopropylacrylamide and oligo(ethylene glycol) comonomers. The intelligent elastomeric patches strongly responded to different humidities and temperatures in terms of mechanical properties which made them applicable for soft robotics and smart skin applications where autonomous adaption to environmental conditions was a key requirement. Beyond using the hydrogel in the conventional state in aqueous media, the new patches could be controlled by relative humidity. The humidity programming of the patches allowed to tune drug release kinetics, […]

Using AI, scientists find a drug that could combat drug-resistant infections

MIT News  May 25, 2023 Discovering new antibiotics against Acinetobacter baumannii, a pathogen that often displays multidrug resistance has proven challenging through conventional screening approaches. An international team of researchers (Canada, USA – MIT, Harvard University) screened ~7,500 molecules for those that inhibited the growth of A. baumannii in vitro and trained a neural network with this growth inhibition dataset and performed in silico predictions for structurally new molecules with activity against A. baumannii. They discovered abaucin, an antibacterial compound with narrow-spectrum activity against A. baumannii. Further investigations revealed that abaucin perturbs lipoprotein trafficking, and it could control an A. […]

Tiny biobattery with potential 100-year shelf life runs on bacteria

Phys.org  April 12, 2023 Controllable microbial electrocatalytic activity in a miniaturized microbial fuel cells (MFCs) with unlimited biodegradable energy resources would enable simple power generation in various environmental settings. However, the short shelf-life of living biocatalysts, few ways to activate the stored biocatalysts, and extremely low electrocatalytic capabilities render the miniature MFCs unsuitable for practical use. Researchers at State University of New York at Binghamton used heat-activated Bacillus subtilis spores as a dormant biocatalyst that could survive storage and rapidly germinate when exposed to special nutrients that are preloaded in the device. A microporous, graphene hydrogel allowed the adsorption of […]

Photosynthesis ‘hack’ could lead to new ways of generating renewable energy

Science Daily  March 22, 2023 Previous approaches to ‘re-wire’ photosynthesis for higher biomass-conversion efficiencies and new reaction pathways have focused on charge extraction at terminal electron acceptors of the photosystems. Electron extraction at earlier steps, perhaps immediately from photoexcited reaction centres, would enable greater thermodynamic gains. Using in vivo ultrafast transient absorption (TA) spectroscopy an international team of researchers (UK, Finland, Germany) demonstrated the extraction of electrons directly from photoexcited PSI and PSII at early points (several picoseconds post-photo-excitation) with live cyanobacterial cells or isolated photosystems, and exogenous electron mediators. They postulated that these mediators oxidize peripheral chlorophyll pigments participating […]

Ultra-lightweight multifunctional space skin created to withstand extreme conditions in space

Nanowerk  March 22, 2023 Current tissue engineering approaches combine different scaffold materials with living cells to provide biological substitutes that can repair and eventually improve tissue functions. Both natural and synthetic materials have been fabricated for transplantation of stem cells and their specific differentiation into muscles, bones, and cartilages. One of the key objectives for bone regeneration therapy to be successful is to direct stem cells’ proliferation and to accelerate their differentiation in a controlled manner using growth factors and osteogenic inducers. An international team of researchers (Singapore, South Korea) has shown that graphene provides a promising biocompatible scaffold that […]

Software lets researchers create tiny rounded objects out of DNA. Here’s why that’s cool

Phys.org  December 23, 2022 A team of researchers in the US (Duke University, UCSF, Arizona State University, Rutgers University, NCAR) has developed and automated the application of a set of previously unknown design principles that now includes a multilayer design for closed and curved DNA nanostructures to resolve past obstacles in shape selection, yield, mechanical rigidity, and accessibility. The objects were made from threadlike molecules of DNA, bent, and folded into complex three-dimensional objects with nanometer precision. They designed, analyzed, and experimentally demonstrated a set of diverse 3D curved nanoarchitectures, showing planar asymmetry and examining partial multilayer designs. The automated […]

Team creates protein-based material that can stop supersonic impacts

Phys.org  December 13, 2022 Extreme energy dissipating materials are essential for a range of applications, in the military, law enforcement, aerospace industry to name a few. Researchers in the UK have created and patented a new shock-absorbing material that could revolutionize both the defense and planetary science sectors. They incorporated a recombinant form of the mechanosensitive protein talin into a monomeric unit and crosslinked, resulting in the production of a talin shock absorbing material (TSAM). When subjected to 1.5 km/s supersonic shots, TSAMs were shown not only to absorb the impact, but to capture/preserve the projectile. According to the researchers […]

Chemists create quantum dots at room temperature using lab-designed protein

Phys.org  December 12, 2022 Researchers at Princeton University used a lab-designed protein (ConK) which facilitated the formation of cadmium sulfide quantum dots by catalyzing the production of a reactive sulfur species from the amino acid cysteine. ConK catalyzed the desulfurization of cysteine to H2S, which was used to synthesize CdS nanocrystals in solution. The quantum dots had optical properties like those seen in chemically synthesized quantum dots. CdS nanocrystals synthesized using ConK have slower growth rates and a different growth mechanism than those synthesized using natural biomineralization pathways and have two desirable properties not observed during biomineralization using natural proteins […]