Biology subjects

Shchelik, I. S.

Publications and source records attributed to Shchelik, I. S..

3 recordsLinked to original sources

bioRxiv2021

Synthesis and biological evaluation of new cephalosporin derivatives containing cyclic disulfide moieties

Due to a steady increase of microbial resistance, there is a need to increase the effectiveness of antibiotic performance by involving additional mechanisms of their penetration or retention for their better action. Cephalosporins are a successful group of antibiotics to combat pathogenic microorganisms, including drug-resistant strains. In this study, we investigated the effect of newly synthesized cephalosporin derivatives with cyclic disulfide modifications against several Gram-positive and Gram-negative strains as well as against biofilm formation. The incorporation of asparagusic acid was found to be effective in improving the activity of the drug against Gram-negative strains compared to the all carbon control compounds. Furthermore, we could demonstrate the successful reduction of biofilm formation for Staphylococcus aureus and Pseudomonas aeruginosa at similar concentrations as obtained against planktonic cells. We propose that the incorporation of cyclic disulfides is one additional strategy to improve antibiotic activity and to combat bacterial infections.

microbiology↗

bioRxiv2021

Thiol and Disulfide Containing Vancomycin Derivatives Against Bacterial Resistance and Biofilm Formation

Antibiotic-resistant and biofilm-associated infections constitute a rapidly growing issue. Use of the last resort antibiotic vancomycin is under threat, due to the increasing appearance of vancomycin resistant bacteria as well as the formation of biofilms. Herein, we report a series of novel vancomycin derivatives carrying thiol- and disulfide-containing moieties. The new compounds exhibited enhanced antibacterial activity against a broad range of bacterial strains, including vancomycin resistant microbes and Gram-negative bacteria. Moreover, all obtained derivatives demonstrated improved antibiofilm formation activity against VanB resistant Enterococcus compared to vancomycin. This work established a promising strategy for combating drug-resistant bacterial infections or disrupting biofilm formation and advances the knowledge on structural optimization of antibiotics with sulfur-containing modifications.

microbiology↗

bioRxiv2021

Biohybrid Microswimmers Against Bacterial Infections

Biohybrid microswimmers exploit the natural abilities of motile microorganisms e.g. in releasing cargo on-demand with high spatial and temporal control. However, using such engineered swarms to deliver antibiotics addressing bacterial infections has not yet been realized. In the present study, a design strategy for biohybrid microswimmers is reported, which features the covalent attachment of antibiotics to the motile green algae Chlamydomonas reinhardtii via a photo-cleavable linker. The surface engineering of the algae does not rely on genetic manipulations, proceeds with high efficiency, does not impair the viability or phototactic ability of microalgae, and allows for caging of the antibiotic on the surface for subsequent release via external stimuli. Two different antibiotic classes have been separately utilized, which result in activity against both gram-positive and gram-negative strains. Guiding the biohybrid microswimmers by an external beacon, and on-demand delivery of the drugs by light with high spatial and temporal control, allowed for strong inhibition of bacterial growth in vivo. This efficient strategy could potentially allow for the selective treatment of bacterial infections by engineered algal microrobots with high precision in space and time. Overall, this work presents an operationally simple production of biohybrid microswimmers loaded with antibiotic cargo to combat bacterial infections precisely delivered in three-dimensional space.

synthetic biology↗