The CYSTM (cysteine-rich transmembrane module) protein family comprises small molecular cysteine-rich tail-anchored membrane proteins found in many eukaryotes. The Saccharomyces cerevisiae strains carrying the CYSTM genes YDRO34W-B and YBR056W-A (MNC1) fused with GFP were used to test the expression of these genes under different stresses. The YBR056W-A (MNC1) and YDR034W-B genes are expressed under stress conditions caused by the toxic concentrations of heavy metal ions, such as manganese, cobalt, nickel, zinc, cuprum, and 2.4-dinitrophenol uncoupler. The expression level of YDR034W-B was higher than that of YBR056W-A under alkali and cadmium stresses. The Ydr034w-b-GFP and Ybr056w-a-GFP proteins differ in the cellular localization: Ydr034w-b-GFP was mainly observed in the plasma membrane and vacuolar membrane, while Ybr056w-a-GFP was observed in the cytoplasm, probably in intracellular membranes. The null-mutants in both genes demonstrated decreased cell concentration and lytic phenotype when cultivated in the presence of excess manganese. This allows for speculations about the involvement of Mnc1 and Ydr034w-b proteins in manganese stress overcoming.

The cell wall of Candida yeast grown on presence of hexadecane as a sole carbon source undergoes structural and functional changes including the formation of specific supramolecular complexes—canals. The canals contain specific polysaccharides and enzymes that provide primary oxidization of alkanes. In addition, inorganic polyphosphate (polyP) was identified in Candida maltosa canals. The aim of the work was a comparative study of the features of cell walls and extracellular structures in yeast C. maltosa, C. albicans and C. tropicalis with special attention to inorganic polyphosphates as possible part of these structures when grown on the widely used xenobiotic hexadecane (diesel fuel). Fluorescence microscopy with DAPI has shown an unusual localization of polyP on the cell surface and in the exovesicles in the three yeast species, when growing on hexadecane. Electron-scanning microscopy showed that the exovesicles were associated with the cell wall and also presented in the external environment probably as biofilm components. Treatment of hexadecane-grown cells with purified Ppx1 polyphosphatase led to the release of phosphate into the incubation medium and the disappearance of polyP in vesicles and cell wall observed using microscopic methods. The results indicate the important role of polyP in the formation of extracellular structures in the Candida yeast when consuming hexadecane and are important for the design of xenobiotic destructors based on yeast or mixed cultures.

The CYSTM (cysteine-rich transmembrane module) protein family comprises small molecular cysteine-rich tail-anchored membrane proteins found in many eukaryotes. The Saccharomyces cerevisiae strains carrying the CYSTM genes YDRO34W-B and YBR056W-A (MNC1) fused with GFP were used to test expression of these genes under different stresses. The YBR056W-A (MNC1) and YDR034W-B genes are expressed under stress conditions caused by the toxic concentrations of heavy metal ions such as manganese, cobalt, nickel, zinc, cuprum, and 2.4-dinitrophenol uncoupler. YDR034W-B but not YBR056W-A is expressed under alkali and cadmium stresses. YBR056W-A is localized in intracellular membranes, while YDR034W-B is localized in the cytoplasmic membrane. The null-mutants in both genes demonstrated both decreased cell concentration and lytic phenotype when cultivated in the presence of excess manganese. This indicates the involvement of Mnc1 and YDR034W-B proteins in manganese detoxification, probably by complexation of its ion.

This study demonstrates the feasibility of encapsulating Paracoccus yeei VKM B-3302 cells, which contain palladium nanoparticles, within an organosilicon matrix synthesized using the sol–gel method. The resulting organosilicon material is characterized by a well-developed porous structure and a high specific surface area, ensuring the formation of a catalytic system with accessible active sites. Kinetic studies of the Mizoroki–Heck reaction showed that, although encapsulating the Pd/P. yeei catalyst in an organosilicon matrix slightly decreases its initial reaction rate, it increases the selectivity of the process and reduces the leaching of the active metal during repeated use. These results suggest the potential of encapsulating microorganisms containing metal nanoparticles in organosilicon materials to create stable hybrid catalytic systems.

For the first time, hydrogels based on silica- and titanium-poly(ethylene glycol) have been used for immobilization of Gram-negative bacteria (Escherichia coli MG1655) and Gram-positive bacteria (Rhodococcus qingshengii X5) in a one-step sol–gel synthesis. Vibrational spectroscopy and thermogravimetric analysis have confirmed the formation of amorphous hybrid structures with a predominance of organic components and metal-oxide grids. Encapsulation efficiencies were 72–77% for Si-PEG-based hydrogel and 50–54% for Ti-PEG. Antimicrobial activity tests revealed that Si-PEG was non-toxic, while Ti-PEG reduced cell viability by 50%. For the first time, an analysis of the morphological properties of immobilized bacterial cells revealed the formation of a thin Si-PEG-based hydrogel shell around each cell and a thick polymer layer on the bacterial surface when encapsulated within Ti-PEG-based hydrogels. The catalytic activity of the biocatalysts, as measured by the ATP content, remained at 84–93% for Si-PEG-based hydrogel, and decreased to 5% for Ti-PEG-based hydrogel. Biocatalysts based on encapsulated bacteria in a Si-PEG-based hydrogel demonstrate high sensitivity and stability. Si-PEG-based hydrogel exhibits high biocompatibility, making it suitable for the effective encapsulation of various bacterial types with a “cell-in-shell” structure.