Bacterial kinetics-controlled shape-directed biosynthesis of silver nanoplates using Morganella psychrotolerans

We show for the first time that by controlling the growth kinetics of Morganella psychrotolerans, a silver-resistant psychrophilic bacterium, the shape anisotropy of silver nanoparticles can be achieved. This is particularly important considering that there has been no report that demonstrates a control over shape of Ag nanoparticles by controlling the growth kinetics of bacteria during biological synthesis. Additionally, we have for the first time performed electrochemistry experiments on bacterial cells after exposing them to Ag(+) ions, which provide significant new insights about mechanistic aspects of Ag reduction by bacteria. The possibility to achieve nanoparticle shape control by using a "green" biosynthesis approach is expected to open up new exciting avenues for eco-friendly, large-scale, and economically viable shape-controlled synthesis of nanomaterials.     

Evaluation of Glycosyl Hydrolases in the Secretome of <Emphasis Type="Italic">Aspergillus fumigatus</Emphasis> and Saccharification of Alkali-Treated Rice Straw

A thermotolerant Aspergillus fumigatus strain isolated from composting pile of mixed industrial waste was found to produce a spectrum of cellulase and hemicellulases when cultured on rice straw solidified substrate. The two-dimensional electrophoresis (2DE) resolved the secretome into 57 distinct protein spots. The zymograms developed against 2DE gels identified the presence of three β-glucosidases and five CBHI/EGI isoforms in the secretome. The peptide mass fingerprinting of 17 protein spots by liquid chromatography mass spectrometry characterized the secretome into different glycosyl hydrolase families. The enzyme cocktail produced by A. fumigatus was capable of efficient hydrolysis of alkali pretreated rice straw (at 7% and 10% w/v) resulting in 95% and 91% saccharification, respectively.     

Electrochemical fabrication of metallic nanostructured electrodes for electroanalytical applications

The use of electrodeposited metal-based nanostructures for electroanalytical applications has recently received widespread attention. There are several approaches to creating nanostructured materials through electrochemical routes that include facile electrodeposition at either untreated or modified electrodes, or through the use of physical or chemical templating methods. This allows the shape, size and composition of the nanomaterial to be readily tuned for the application of interest. The use of such materials is particularly suited to electroanalytical applications. In this mini-review an overview of recently developed nanostructured materials developed through electrochemical routes is presented as well as their electroanalytical applications in areas of biological and environmental importance.     

Preliminary estimate of branching ratios of weak hadronic decays of bottom baryons emitting charmless scalar mesons

In this paper we study one-dimensional static self-dual non-topological solitons in an Abelian-Higgs Chern–Simons model with a non-canonical kinetic term. We choose a scalar potential with a single minimum and present an analytical soliton solution which corresponds to an electrically charged lump-like soliton without total momentum and located in a region where the scalar field gets maximum. The solitonic boundary conditions impose a discontinuity on the electric field across the soliton line where, then, there is a linear charge density.     

Identifying structural–functional analogue of GRL0617, the only well-established inhibitor for papain-like protease (PLpro) of SARS-CoV2 from the pool of fungal metabolites using docking and molecular dynamics simulation

Molecular Diversity - The non-structural protein (nsp)-3 of SARS-CoV2 coronavirus is sought to be an essential target protein which is also named as papain-like protease (PLpro). This protease...     

Dynamic synchronization of a time-evolving optical network of chaotic oscillators

We present and experimentally demonstrate a technique for achieving and maintaining a global state of identical synchrony of an arbitrary network of chaotic oscillators even when the coupling strengths are unknown and time-varying. At each node an adaptive synchronization algorithm dynamically estimates the current strength of the net coupling signal to that node. We experimentally demonstrate this scheme in a network of three bidirectionally coupled chaotic optoelectronic feedback loops and we present numerical simulations showing its application in larger networks. The stability of the synchronous state for arbitrary coupling topologies is analyzed via a master stability function approach.     

Systematic study of rigid triaxiality in Ba–Pt nuclei and role of $$$$ subshell effect

A systematic variation of shape variables \(\beta \) and \(\gamma \) with N and \(N_\mathrm {p}N_\mathrm {n}\) is studied in the framework of an asymmetric rotor model of Davydov and Filippov for the \(Z=\) 50–82, \(N=\) 82–126 major shell space. The role of the \(Z=64\) subshell in producing smooth systematics has been discussed. The quadrupole moments are extracted after considering both axially symmetric and axially asymmetric nuclei. The correlation of \(\beta \) with \(\gamma \) together with the measured quadrupole moments indicates that \(\gamma \)-rigidity is better observed in nuclei with modest deformation.     

(−)-Adaline from the Adalia Genus of Ladybirds Is a Potent Antagonist of Insect and Specific Mammalian Nicotinic Acetylcholine Receptors

Ladybird beetles (Coleoptera: Coccinellidae) possess strong chemical defences that are secreted in response to stress and are also found on the coating of eggs, which are rich in alkaloids that are responsible for their toxicity to other species. Recent studies have shown that alkaloids from several species of ladybird beetle can target nicotinic acetylcholine receptors (nAChRs) acting as receptor antagonists. Here, we have explored the actions of (−)-adaline, found in the 2-spot (Adalia bipunctata) and 10-spot (Adalia decempunctata) ladybirds, on both mammalian (α1β1γδ, α7, α4β2, α3β4) and insect nAChRs using patch-clamp of TE671 cells and locust brain neurons natively expressing nAChRs, as well as two-electrode voltage clamp of Xenopus laevis oocytes recombinantly expressing nAChRs. All nAChR subtypes were antagonised by (−)-adaline in a time-dependent, voltage-dependent and non-competitive manner with the lowest IC₅₀s at rat α3β4 (0.10 μM) and locust neuron (1.28 μM) nAChRs, at a holding potential of −75 mV. The data imply that (−)-adaline acts as an open channel blocker of nAChRs.     

Uncovering the Contributions of Charge Regulation to the Stability of Single Alpha Helices**

The single alpha helix (SAH) is a recurring motif in biology. The consensus sequence has a di-block architecture that includes repeats of four consecutive glutamate residues followed by four consecutive lysine residues. Measurements show that the overall helicity of sequences with consensus E₄K₄ repeats is insensitive to a wide range of pH values. Here, we use the recently introduced q-canonical ensemble, which allows us to decouple measurements of charge state and conformation, to explain the observed insensitivity of SAH helicity to pH. We couple the outputs from separate measurements of charge and conformation with atomistic simulations to derive residue-specific quantifications of preferences for being in an alpha helix and for the ionizable residues to be charged vs. uncharged. We find a clear preference for accommodating uncharged Glu residues within internal positions of SAH-forming sequences. The stabilities of alpha helical conformations increase with the number of E₄K₄ repeats and so do the numbers of accessible charge states that are compatible with forming conformations of high helical content. There is conformational buffering whereby charge state heterogeneity buffers against large-scale conformational changes thus making the overall helicity insensitive to large changes in pH. Further, the results clearly argue against a single, rod-like alpha helical conformation being the only or even dominant conformation in the ensembles of so-called SAH sequences.