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Biology subjects

Surkov, S.

Publications and source records attributed to Surkov, S..

2 recordsLinked to original sources

LubriShieldTM - a unique permanent coating for indwelling urinary catheters that impedes surface-associated uropathogens from forming biofilm

Catheter-associated urinary tract infection (CAUTI) is one of the most common healthcare-associated infections and biofilm formation plays a key role in its pathogenesis. Indwelling medical devices introduce ideal pathways inside the body for invading pathogens and feature surfaces conducive to biofilm development. These devices are the root cause of severe clinical infections often recalcitrant to antimicrobials. When bacteria and fungi switch to biofilm mode of growth, they produce a matrix in the form of extracellular polymeric substances (EPS). This creates a unique environment for growing virulent colonizers and persisting cells while also forming a shielding barrier against immune system attacks, antimicrobial agents and mechanical removal by fluid shear forces. To address this challenge, LubriShield TM - a novel permanent coating was invented, and evenly applied to both the internal and external surfaces of indwelling urinary Foley catheters. Without releasing active substances, it effectively prevented pathogens from producing biofilm. The coating was superhydrophilic and incorporated a proprietary anti-fouling ligand, which created a surface that significantly inhibited up to 99% of colonizing uropathogens from forming biofilm for the duration of use without any microbial killing (p< 0.001). The predominant uropathogens, including Gram-positive and Gram-negative as well as Candida albicans, were inhibited from forming biofilm on the LubriShieldTM coated surfaces for up to 14 days in artificial urine medium. After challenging the adhering bacteria in a glass bladder flow model, the coating still significantly reduced biofilm formation by 83% (p<0.001). The growth mode and emergent properties of adhering bacteria on uncoated silicone catheter surfaces were compared with those on LubriShieldTM coated surfaces. RNA-seq analysis revealed that gene expression associated with microbial EPS formation was significantly downregulated on the coated surfaces. Additionally, microorganisms adhering to LubriShieldTM coated catheters were 46% more susceptible to antibiotics compared to those on uncoated silicone catheters (p<0.01).

microbiology↗

Rescue of Escherichia coli auxotrophy by de novo small proteins

Increasing numbers of small proteins with diverse physiological roles are being identified and characterized in both prokaryotic and eukaryotic systems, but the origins and evolution of these proteins remain unclear. Recent genomic sequence analyses in several organisms suggest that new functions encoded by small open reading frames (sORFs) may emerge de novo from noncoding sequences. However, experimental data demonstrating if and how randomly generated sORFs can confer beneficial effects to cells are limited. Here we show that by up-regulating hisB expression, de novo small proteins ([&le;] 50 amino acids in length) selected from random sequence libraries can rescue Escherichia coli cells that lack the conditionally essential SerB enzyme. The recovered small proteins are hydrophobic and confer their rescue effect by binding to the 5 end regulatory region of the his operon mRNA, suggesting that protein binding promotes structural rearrangements of the RNA that allow increased hisB expression. This study adds RNA regulatory elements as another interacting partner for de novo proteins isolated from random sequence libraries, and provides further experimental evidence that small proteins with selective benefits can originate from the expression of nonfunctional sequences.

evolutionary biology↗