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The catalytic action of invertase generates bilayer asymmetry that stabilises membrane curvature. The driving mechanism for the generation of membrane curvature by invertase is investigated using giant unilamellar vesicles (GUVs). The invertase cleaves the sucrose in the exterior compartment, thereby creating a sugar asymmetry across the bilayer membrane that is measured for GUV membranes consisting of the lipid Dioleoylphosphatidylcholine (DOPC). Finally, the advantage of this method to control membrane curvature and to stabilize multi‐sphere morphologies is demonstrated. The GUV system in the presence of invertase is beneficial as a tool to generate multiple on‐demand compartments with more extended stability after the enzymatic activity has established the asymmetry. [ABSTRACT FROM AUTHOR]

Herein we report the chemotactic behaviour of alkaline phosphatase (ALP) in the gradients of carbohydrates (glucose, fructose and sucrose) and metal ions, including cofactors (Zn2+ and Mg2+), under microfluidic conditions. We found that ALP migrates marginally away from the carbohydrate gradient, whereas for divalent metal ions, the direction is opposite and more prominent. This differential phoresis is due to the Hofmeister effect driven change in the ALP surface zeta potential and osmotic pressure imbalance. Gaining control over the chemotactic extent and direction of an enzyme in response to purely non-catalytic conditions will have potential application in designing environment-responsive nanomachines. [ABSTRACT FROM AUTHOR]

The inhibitory effect of nucleotides on the catalytic activity of acetylcholine esterase (AChE) was rationalized and a similar inhibition trend was observed when analyzing the macroscopic fluid flow generated by surface immobilized AChE. Additionally, the demonstration of enzymatic micropumping by showing adenine–nucleotide responsive AChE actuated fluid flow from blood plasma paved the way for designing future lab-on-a-chip devices in complex biological environments with potential clinical applications. [ABSTRACT FROM AUTHOR]

Formation of a thermally stiffening microemulsion-based gel showing a nanoconfinement effect of carbohydrates in terms of microviscosity and hydrodynamic diameter of the reverse micelle (specifically with sucrose) is reported. The advantage of this gel as an efficient batch bioreactor for entrapped enzymes (horseradish peroxidase and thermophilic α-glucosidase) was shown, and illustrated its potential biocatalytic application at high temperatures. [ABSTRACT FROM AUTHOR]

• Two re (I) tricarbonyl complexes (1 and 2) were obtained at high yield and the fac form. • DFT and TDDFT calculations were performed to describe the molecular geometries and the photophysics of the complexes. • Emission and lifetime of excited species were measured for both 1 and 2. • The cytotoxicity of 1 and 2 was studied against MCF-7 breast cancer cells. • DNA binding studies confirmed an intercalative mode of interaction. A mononuclear and dinuclear rhenium tricarbonyl compounds were synthesized by the one-pot condensation reaction of [ Re (CO) 5 Br], pyrrole-2-carboxaldehyde and 4‑chloro- m -phenylene diamine. The mononuclear rhenium tricarbonyl complex containing {3-(imino pyrrolyl)- 6 ‑chloro phenylamine)} ligand (IPP) with formula {[ Re (CO) 3 Br(IPP)], (1) , was obtained by refluxing stoichiometric quantities of amine, aldehyde and rhenium metal precursor in methanol solution. Similarly, dinuclear rhenium tricarbonyl compound {[ Re (CO) 3 Br] 2 (BIPP)], BIPP = bis-{1,3-(imino pyrrolyl)- m -chlorophenyl)}, (2) has been synthesized by refluxing appropriate amounts of aldehyde, and rhenium metal precursor in the presence of one equivalent of amine ligand. Compounds 1 and 2 were characterized by FT-IR, 1H NMR, and UV–Vis spectroscopy, elemental analysis, and mass spectrometry. The luminescence properties of the formed complexes were studied in solution at room temperature, revealing an extended lifetime for the dinuclear complex 2 in comparison to 1. DFT calculations for the optimized structures helped to understand the geometry of the complexes, whereas TD-DFT revealed the vertical transitions responsible for the photophysical properties of the complexes. The cytotoxicity of such complexes against MCF-7 breast cancer has been also reported, revealing a dose-dependent growth inhibition attributed to a DNA-intercalating mode of binding for both complexes. The pronounced effect of the two metals on the cytotoxic studies and lifetime of the excited species were investigated. The greater intercalation ability of the complex 2 in comparison to complex 1 obtained from circular dichroism studies also indicates the greater efficacy of Re complex 2. [Display omitted] [ABSTRACT FROM AUTHOR]