Novel Fluoroquinolones With Pinane Moiety: Synthesis and Antimicrobial Activity.

Here, we report a synthesis of fluoroquinolones carrying a monoterpene moiety at the C7 position of aromatic structure. The minimal inhibitory concentrations of fluoroquinolone fused with trans-3-hydroxy-cis-myrtanylamine 18 against Staphylococcus aureus (MSSA isolates) were two- to eightfold lower compared to moxifloxacin, although fourfold higher against MRSA isolates. The fluoroquinolone fused with (-)-nopylamine 16 was four- to eightfold less active on MSSA compared to moxifloxacin, while had similar activity on MRSA.

Targeting mono- and dual-species biofilms of Staphylococcus aureus and Pseudomonas aeruginosa by the recombinant anticoagulant enzyme PAPC from micromycete Aspergillus ochraceus.

Microbial biofilms have recently emerged as a critical target for treating bacterial infections due to their crucial role in developing antibiotic resistance. The wide-spectrum activity of proteolytic enzymes makes them particularly suitable for disrupting biofilms formed by diverse bacterial species, including dual-species biofilms. In this study, we propose the Protease-Activator of Protein C (PAPC) of human blood plasma, an enzyme produced by the micromycete Aspergillus ochraceus, as a novel tool to degrade the protein scaffold of mono- or dual-species biofilms formed by Staphylococcus aureus and Pseudomonas aeruginosa.

A novel terpene-BODIPY conjugates based fluorescent probes: Synthesis, spectral properties, stability, penetration efficiency into bacterial, fungal and mammalian cells.

The design of fluorescent probes based on biocompatible luminophores for medical diagnostics is one of the rapidly developing areas worldwide. Here, we report the synthesis of a novel BODIPYs containing a propanoic acid residue at the α-position of one of the pyrrole rings conjugated to (+)-myrtenol or thiotherpenoid. Both conjugates are quite photostable (t ∼ 40 h) and exhibit high fluorescence efficiency (φ ∼ 77-90 %).

Effect of meso-substituents and medium properties on the photo- and pH-stability, penetration efficiency into bacterial and microscopic fungi cells of terpene-BODIPY conjugates.

In order to expand the arsenal of tools and areas for practical use of BODIPY dyes as bifunctional fluorescent theranostics, we studied the effect of the meso-substituents nature and medium properties on photo- and pH-stability, efficiency of singlet oxygen generation, and affinity to biostructures of terpene-BODIPY conjugates. The BODIPYs fused with myrtenol or thiotherpenoid via carboxylic acid residues exhibit high stability over a wide pH range and the presence of a bulky substituent at the meso-position of BODIPY conjugates increases their photostability two-fold compared to structurally related meso-unsubstituted analogues. Furthermore, the photodegradation rate of the conjugates directly depends on their ability to generate singlet oxygen and the course probability of the corresponding red-ox reactions involving reactive oxygen species.

The Effect of Ficin Immobilized on Carboxymethyl Chitosan on Biofilms of Oral Pathogens.

In the last decade, Ficin, a proteolytic enzyme extracted from the latex sap of the wild fig tree, has been widely investigated as a promising tool for the treatment of microbial biofilms, wound healing, and oral care. Here we report the antibiofilm properties of the enzyme immobilized on soluble carboxymethyl chitosan (CMCh) and CMCh itself. Ficin was immobilized on CMCh with molecular weights of either 200, 350 or 600 kDa.

Alterations in Antibiotic Susceptibility of and in Dual Species Biofilms.

In the last decades, it has been shown that biofilm-associated infections in most cases are caused by rather two or even more pathogens than by single microorganisms. Due to intermicrobial interactions in mixed communities, bacteria change their gene expression profile, in turn leading to alterations in the biofilm structure and properties, as well as susceptibility to antimicrobials. Here, we report the alterations of antimicrobials efficiency in mixed biofilms of - in comparison with mono-species biofilms of each counterpart and discuss possible mechanisms of these alterations.

The Novel Chiral 2(5)-Furanone Sulfones Possessing Terpene Moiety: Synthesis and Biological Activity.

Over the past decades, 2(5)-furanone derivatives have been extensively studied because of their promising ability to prevent the biofilm formation by various pathogenic bacteria. Here, we report the synthesis of a series of optically active sulfur-containing 2(5)-furanone derivatives and characterize their biological activity. Novel thioethers were obtained by an interaction of stereochemically pure 5-()-menthyloxy- or 5-()-bornyloxy-2(5)-furanones with aromatic thiols under basic conditions.

Brightfield vs Fluorescent Staining Dataset-A Test Bed Image Set for Machine Learning based Virtual Staining.

Differential fluorescent staining is an effective tool widely adopted for the visualization, segmentation and quantification of cells and cellular substructures as a part of standard microscopic imaging protocols. Incompatibility of staining agents with viable cells represents major and often inevitable limitations to its applicability in live experiments, requiring extraction of samples at different stages of experiment increasing laboratory costs. Accordingly, development of computerized image analysis methodology capable of segmentation and quantification of cells and cellular substructures from plain monochromatic images obtained by light microscopy without help of any physical markup techniques is of considerable interest.

Increasing the Efficacy of Treatment of - Mixed Infections with Myrtenol.

Infectious diseases caused by various nosocomial microorganisms affect worldwide both immunocompromised and relatively healthy persons. Bacteria and fungi have different tools to evade antimicrobials, such as hydrolysis damaging the drug, efflux systems, and the formation of biofilm that significantly complicates the treatment of the infection. Here, we show that myrtenol potentiates the antimicrobial and biofilm-preventing activity of conventional drugs against and mono- and dual-species cultures.

Biochemical Properties and Anti-Biofilm Activity of Chitosan-Immobilized Papain.

Chitosan, the product of chitin deacetylation, is an excellent candidate for enzyme immobilization purposes. Here we demonstrate that papain, an endolytic cysteine protease (EC: 3.4.

Anti-biofilm and wound-healing activity of chitosan-immobilized Ficin.

Biofouling is among the key factors slowing down healing of acute and chronic wounds. Here we report both anti-biofilm and wound-healing properties of the chitosan-immobilized Ficin. The proposed chitosan-adsorption approach allowed preserving ~90% of the initial total activity of the enzyme (when using azocasein as a substrate) with stabilization factor of 4.

Bidirectional alterations in antibiotics susceptibility in Staphylococcus aureus-Pseudomonas aeruginosa dual-species biofilm.

In mixed infections, the bacterial susceptibility differs significantly compared to monocultures of bacteria, and generally the concentrations of antibiotics required for the treatment increases drastically. For S. aureus and P.

Targeting Bacillus cereus cells: increasing efficiency of antimicrobials by the bornylpossessing 2(5Н)-furanone derivative.

Among a variety of antimicrobial compounds, the derivatives of 2(5H)-furanone exhibit different effects on Firmicutes and Proteobacteria. While inhibiting quorum-dependent biofilm formation and virulence factor expression by Gram-negative bacteria through specific interference with the AI-2 signaling pathways, these compounds demonstrate bactericidal effects against Gram-positive bacteria. Here we report that 3,4-dichloro-5(S)-[(1S,2R,4S)-1,7,7-trimethylbicyclo[2.

Fast and simple tool for the quantification of biofilm-embedded cells sub-populations from fluorescent microscopic images.

Fluorescent staining is a common tool for both quantitative and qualitative assessment of pro- and eukaryotic cells sub-population fractions by using microscopy and flow cytometry. However, direct cell counting by flow cytometry is often limited, for example when working with cells rigidly adhered either to each other or to external surfaces like bacterial biofilms or adherent cell lines and tissue samples. An alternative approach is provided by using fluorescent microscopy and confocal laser scanning microscopy (CLSM), which enables the evaluation of fractions of cells subpopulations in a given sample.

Antimicrobial Effects of Sulfonyl Derivative of 2(5)-Furanone against Planktonic and Biofilm Associated Methicillin-Resistant and -Susceptible .

The gram-positive opportunistic bacterium is one of the most common causatives of a variety of diseases including skin and skin structure infection or nosocomial catheter-associated infections. The biofilm formation that is an important virulence factor of this microorganism renders the antibiotic therapy ineffective, because biofilm-embedded bacteria exhibit strongly increased tolerance to antimicrobials. Here, we describe a novel 3-chloro-5()-[(1,2,5)-2-isopropyl-5-methylcyclohexyloxy]-4-[4-methylphenylsulfonyl]-2(5)-furanone (), possessing a sulfonyl group and -menthol moiety.

Targeting microbial biofilms using Ficin, a nonspecific plant protease.

Biofilms, the communities of surface-attached bacteria embedded into extracellular matrix, are ubiquitous microbial consortia securing the effective resistance of constituent cells to environmental impacts and host immune responses. Biofilm-embedded bacteria are generally inaccessible for antimicrobials, therefore the disruption of biofilm matrix is the potent approach to eradicate microbial biofilms. We demonstrate here the destruction of Staphylococcus aureus and Staphylococcus epidermidis biofilms with Ficin, a nonspecific plant protease.

New Derivatives of Pyridoxine Exhibit High Antibacterial Activity against Biofilm-Embedded Staphylococcus Cells.

Opportunistic bacteria Staphylococcus aureus and Staphylococcus epidermidis often form rigid biofilms on tissues and inorganic surfaces. In the biofilm bacterial cells are embedded in a self-produced polysaccharide matrix and thereby are inaccessible to biocides, antibiotics, or host immune system. Here we show the antibacterial activity of newly synthesized cationic biocides, the quaternary ammonium, and bisphosphonium salts of pyridoxine (vitamin B6) against biofilm-embedded Staphylococci.

Inhibition of biofilm formation in Bacillus subtilis by new halogenated furanones.

Gram-positive bacteria can cause various infections including hospital-acquired infections. While in the biofilm, the resistance of bacteria to both antibiotics and the human immune system is increased causing difficulties in the treatment. Bacillus subtilis, a non-pathogenic Gram-positive bacterium, is widely used as a model organism for studying biofilm formation.