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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]