Nanoshell Assembly for Magnet-Responsive Oil-Degrading Bacteria

Abstract

The modified polyelectrolyte-magnetite nanocoating was applied to functionalize the cell walls of oil decomposing bacteria Alcanivorax borkumensis. Cationic coacervate of poly(allylamine) and 20 nm iron oxide nanoparticles allowed for a rapid single-step encapsulation process exploiting electrostatic interaction with bacteria surfaces. The bacteria were covered with rough 70-100-nm-thick shells of magnetite loosely bound to the surface through polycations. This encapsulation allowed for external manipulations of A. borkumensis with magnetic field, as demonstrated by magnetically facilitated cell displacement on the agar substrate. Magnetic coating was naturally removed after multiple cell proliferations providing next generations of the cell in the native nonmagnetic form. The discharged biosurfactant vesicles indicating the bacterial functionality (150 ± 50 nm lipid micelles) were visualized with atomic force microscopy in the bacterial biofilms.

Halloysites Stabilized Emulsions for Hydroformylation of Long Chain Olefins

“…The MTT-test results also indicate that there is no severe reduction in enzymatic activity of NAD(P) H (nicotinamide adenine dinucleotide phosphate)-dependent oxidoreductases. [21][22][23] One of the main goals of spilled oil halloysite emulsification is to optimize its consumption via degrading bacteria, and this may be reached: (1) by maximizing the oil surface area which is inversely proportional to the droplet radius (e.g., decreasing the oil droplet diameter from 1 mm to 10 μm increases the resulting multiplied droplets' surface 100 times), and (2) by increasing of the droplet surface roughness, improving bacterial cell attachment and proliferation. One can see, that halloysite nanotubes are comparable in sizes with bacteria and do not penetrate into the cell interior ( Figure 9C).…”

“…[19,20] This allowed to disperse petroleum spots and could result in faster bioremediation of the spill by naturally occurring degrading microorganisms such as A. borkumensis. [21][22][23] One of the main goals of spilled oil halloysite emulsification is to optimize its consumption via degrading bacteria, and this may be reached: (1) by maximizing the oil surface area which is inversely proportional to the droplet radius (e.g., decreasing the oil droplet diameter from 1 mm to 10 μm increases the resulting multiplied droplets' surface 100 times), and (2) by increasing of the droplet surface roughness, improving bacterial cell attachment and proliferation. We proved halloysite safety for A. borkumensis as one of the established bacterial organisms for both aliphatic and conjugated oil component decomposition, and its use for oil emulsification looks very promising.…”

Biomedical Applications of Layer‐by‐Layer Self‐Assembly for Cell Encapsulation: Current Status and Future Perspectives

“…The electrostatic attraction between the polyelectrolyte and charged nanoparticles could facilitate the adsorption of charged nanoparticles onto cell surface, support the stability of the architecture, and prevent the internalization of nanoparticle into the cytoplasm. Recently, some researchers also reported the direct deposition of polyelectrolyte‐stabilized nanoparticles onto cells by electrostatic interaction to achieve cell surface functionalization …”

Strategic Advances in Formation of Cell‐in‐Shell Structures: From Syntheses to Applications

“…The cytoprotective shells also have been functionalized chemically further to meet the application requirements. For example, the magnetized cells could be spatially manipulated, concentrated, and isolated en masse, beneficial in the facile recycling of biocatalytic cells and localization of biosensing cells in a device, in addition to tissue‐engineering applications …”

“…[50b] On the other hand, oil‐degrading Alcanivorax borkumensis was magnetized for potential application to bioreactor‐based oil‐processing devices. [46a]…”