scholarly journals Synthesis, Tyrosinase Inhibiting Activity and Molecular Docking of Fluorinated Pyrazole Aldehydes as Phosphodiesterase Inhibitors

2019 ◽  
Vol 9 (8) ◽  
pp. 1704
Author(s):  
Vesna Rastija ◽  
Harshad Brahmbhatt ◽  
Maja Molnar ◽  
Melita Lončarić ◽  
Ivica Strelec ◽  
...  
Keyword(s):  
Catalytic Domain ◽  
Antibacterial Properties ◽  
Phosphodiesterase Inhibitors ◽  
Pyrazole Ring ◽  
Binding Mode ◽  
Van Der Waals Interactions ◽  
Side Chain ◽  
Bacterial Strains ◽  
1H And 13C Nmr ◽  
Monophenolase Activity

A series of fluorinated 4,5-dihydro-1H-pyrazole derivatives were synthesized in the reaction of corresponding acetophenone and different aldehydes followed by the second step synthesis of desired compounds from synthesized chalcone, hydrazine hydrate, and formic acid. Structures of all compounds were confirmed by both 1H and 13C NMR and mass spectrometry. Antibacterial properties of compounds were tested on four bacterial strains, Escherichia coli, Pseudomonas aeruginosa, Bacillus subtilis, and Staphylococcus aureus. Among synthesized compounds, the strongest inhibitor of monophenolase activity of mushroom tyrosinase (32.07 ± 3.39%) was found to be 5-(2-chlorophenyl)-3-(4-fluorophenyl)-4,5-dihydro-1H-pyrazole-1-carbaldehyde. The PASS program has predicted the highest probable activity for the phosphodiesterase inhibition. To shed light on molecular interactions between the synthesized compounds and phosphodiesterase, all compounds were docked into the active binding site. The obtained results showed that the compound with the dimethoxyphenyl ring could be potent as an inhibitor of phosphodiesterase, which interacts in PDE5 catalytic domain of the enzyme. Key interactions are bidentate hydrogen bond (H-bond) with the side-chain of Gln817 and van der Waals interactions of the dimethoxyphenyl ring and pyrazole ring with hydrophobic clamp, which contains residuals, Val782, Phe820, and Tyr612. Interactions are similar to the binding mode of the inhibitor sildenafil, the first oral medicine for the treatment of male erectile dysfunction.

scholarly journals Decoding Antibacterial and Antibiofilm Properties of Cinnamon and Cardamom Essential Oils: A Combined Molecular Docking and Experimental Study

2021 ◽  
Author(s):  
Elahe Pourkhosravani ◽  
fatemeh dehghan nayeri ◽  
Mitra Mohammadi Bazargani
Keyword(s):  
Cell Attachment ◽  
Antibacterial Properties ◽  
Binding Mode ◽  
Dilution Method ◽  
Antibiofilm Activity ◽  
Bacterial Strains ◽  
Biofilm Growth ◽  
Computational Docking ◽  
E Coli ◽  
Industrial Strains

Abstract This study sets out to compare the antibacterial and antibiofilm profiles of Ci/Ca EOs alone and in combination together against infectious bacterial strains. MIC assay was carried out to survey the effectiveness of prepared EOs by two-fold serial dilution method and MTT evaluation. Synergic antibacterial properties of EOs against target strains were studied by using checkerboard titration method. Biofilm growth and development were evaluated using CV and XTT reduction assays. Antibacterial activity was observed for EOs against both bacterial strains with stronger activity for CiEO against both bacteria. The synergistic antibacterial effect was observed only against B. subtilis. Based on the FIC index, combinations could not inhibit the growth of E. coli. The pure EOs and their combination inhibited cell attachment for both studied bacteria with stronger effect on E. coli. CV and XTT reduction assays results showed that Ci EO and its combination with CaEO had the highest antibiofilm activity at lowest MIC value 0.08% and 0.04/0.02% against biofilm formed by E. coli and B. subtilis respectively, indicating a high antibiofilm potential. Computational docking analyses also postulated that the active constituents of evaluated EOs have the potential to interact with different bacterial targets, suggested binding mode of action of EOs metabolites. By and large, synergistic anti-biofilm properties of EOs may provide further options for developing novel formula to inhibit a variety of infectious clinical and industrial strains without (or less) toxicity effects on human body.

scholarly journals Decoding antibacterial and antibiofilm properties of cinnamon and cardamom essential oils: a combined molecular docking and experimental study

AMB Express ◽  
2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Elahe Pourkhosravani ◽  
Fatemeh Dehghan Nayeri ◽  
Mitra Mohammadi Bazargani
Keyword(s):  
Cell Attachment ◽  
Antibacterial Properties ◽  
Binding Mode ◽  
Dilution Method ◽  
Antibiofilm Activity ◽  
Bacterial Strains ◽  
Biofilm Growth ◽  
Computational Docking ◽  
E Coli ◽  
Industrial Strains

AbstractThis study sets out to compare the antibacterial and antibiofilm profiles of Ci/Ca EOs alone and in combination together against infectious bacterial strains. MIC assay was carried out to survey the effectiveness of prepared EOs by two-fold serial dilution method and MTT evaluation. Synergic antibacterial properties of EOs against target strains were studied by using checkerboard titration method. Biofilm growth and development were evaluated using CV and XTT reduction assays. Antibacterial activity was observed for EOs against both bacterial strains with stronger activity for CiEO against both bacteria. The synergistic antibacterial effect was observed only against B. subtilis. Based on the FIC index, combinations could not inhibit the growth of E. coli. The pure EOs and their combination inhibited cell attachment for both studied bacteria with stronger effect on E. coli. CV and XTT reduction assays results showed that Ci EO and its combination with CaEO had the highest antibiofilm activity at lowest MIC value 0.08% and 0.04/0.02% against biofilm formed by E. coli and B. subtilis respectively, indicating a high antibiofilm potential. Computational docking analyses also postulated that the active constituents of evaluated EOs have the potential to interact with different bacterial targets, suggested binding mode of action of EOs metabolites. By and large, synergistic anti-biofilm properties of EOs may provide further options for developing novel formula to inhibit a variety of infectious clinical and industrial strains without (or less) toxicity effects on human body. Graphical Abstract

scholarly journals Effect of Gold Nanoparticles and Silicon on the Bioactivity and Antibacterial Properties of Hydroxyapatite/Chitosan/Tricalcium Phosphate-Based Biomicroconcretes

Materials ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 3854
Author(s):  
Joanna Czechowska ◽  
Ewelina Cichoń ◽  
Anna Belcarz ◽  
Anna Ślósarczyk ◽  
Aneta Zima
Keyword(s):  
Gold Nanoparticles ◽  
Antibacterial Activity ◽  
Tricalcium Phosphate ◽  
Setting Time ◽  
Antibacterial Properties ◽  
Bone Substitutes ◽  
Bacterial Strains ◽  
Setting Times ◽  
Biological Studies

Bioactive, chemically bonded bone substitutes with antibacterial properties are highly recommended for medical applications. In this study, biomicroconcretes, composed of silicon modified (Si-αTCP) or non-modified α-tricalcium phosphate (αTCP), as well as hybrid hydroxyapatite/chitosan granules non-modified and modified with gold nanoparticles (AuNPs), were designed. The developed biomicroconcretes were supposed to combine the dual functions of antibacterial activity and bone defect repair. The chemical and phase composition, microstructure, setting times, mechanical strength, and in vitro bioactive potential of the composites were examined. Furthermore, on the basis of the American Association of Textile Chemists and Colorists test (AATCC 100), adapted for chemically bonded materials, the antibacterial activity of the biomicroconcretes against S. epidermidis, E. coli, and S. aureus was evaluated. All biomicroconcretes were surgically handy and revealed good adhesion between the hybrid granules and calcium phosphate-based matrix. Furthermore, they possessed acceptable setting times and mechanical properties. It has been stated that materials containing AuNPs set faster and possess a slightly higher compressive strength (3.4 ± 0.7 MPa). The modification of αTCP with silicon led to a favorable decrease of the final setting time to 10 min. Furthermore, it has been shown that materials modified with AuNPs and silicon possessed an enhanced bioactivity. The antibacterial properties of all of the developed biomicroconcretes against the tested bacterial strains due to the presence of both chitosan and Au were confirmed. The material modified simultaneously with AuNPs and silicon seems to be the most promising candidate for further biological studies.

scholarly journals Prenylated Flavonoids and C-15 Isoprenoid Analogues with Antibacterial Properties from the Whole Plant of Imperata cylindrica (L.) Raeusch (Gramineae)

Molecules ◽  
2021 ◽  
Vol 26 (16) ◽  
pp. 4717
Author(s):  
Romeo Nago ◽  
Paul Nayim ◽  
Armelle Mbaveng ◽  
James Mpetga ◽  
Gabin Bitchagno ◽  
...  
Keyword(s):  
Silica Gel ◽  
Methanol Extract ◽  
Antibacterial Properties ◽  
Imperata Cylindrica ◽  
Drug Resistant ◽  
Bacterial Strains ◽  
Prenylated Flavonoids ◽  
Whole Plant ◽  
Crude Methanol Extract ◽  
Potential Origin

The local botanical Imperata cylindrica in Cameroon was investigated for its antibacterial potency. The methanol extract afforded a total of seven compounds, including five hitherto unreported compounds comprising three flavonoids (1–3) and two C-15 isoprenoid analogues (4 and 5) together with known derivatives (6 and 7). The novelty of the flavonoids was related to the presence of both methyl and prenyl groups. The potential origin of the methyl in the flavonoids is discussed, as well as the chemophenetic significance of our findings. Isolation was performed over repeated silica gel and Sephadex LH-20 column chromatography and the structures were elucidated by (NMR and MS). The crude methanol extract and isolated compounds showed considerable antibacterial potency against a panel of multi-drug resistant (MDR) bacterial strains. The best MIC values were obtained with compound (2) against S. aureus ATCC 25923 (32 µg/mL) and MRSA1 (16 µg/mL).

scholarly journals Synthesis, Characterization, Antibacterial Properties, and In Vitro Studies of Selenium and Strontium Co-Substituted Hydroxyapatite

2021 ◽  
Vol 22 (8) ◽  
pp. 4246
Author(s):  
Muhammad Maqbool ◽  
Qaisar Nawaz ◽  
Muhammad Atiq Ur Atiq Ur Rehman ◽  
Mark Cresswell ◽  
Phil Jackson ◽  
...  
Keyword(s):  
Negative Impact ◽  
Antibacterial Properties ◽  
Biological Properties ◽  
Ion Concentration ◽  
Charge Composition ◽  
Bacterial Strains ◽  
X Ray Diffraction ◽  
Molar Ratios ◽  
Human Osteosarcoma Cells

In this study, as a measure to enhance the antimicrobial activity of biomaterials, the selenium ions have been substituted into hydroxyapatite (HA) at different concentration levels. To balance the potential cytotoxic effects of selenite ions (SeO32−) in HA, strontium (Sr2+) was co-substituted at the same concentration. Selenium and strontium-substituted hydroxyapatites (Se-Sr-HA) at equal molar ratios of x Se/(Se + P) and x Sr/(Sr + Ca) at (x = 0, 0.01, 0.03, 0.05, 0.1, and 0.2) were synthesized via the wet precipitation route and sintered at 900 °C. The effect of the two-ion concentration on morphology, surface charge, composition, antibacterial ability, and cell viability were studied. X-ray diffraction verified the phase purity and confirmed the substitution of selenium and strontium ions. Acellular in vitro bioactivity tests revealed that Se-Sr-HA was highly bioactive compared to pure HA. Se-Sr-HA samples showed excellent antibacterial activity against both Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus carnosus) bacterial strains. In vitro cell–material interaction, using human osteosarcoma cells MG-63 studied by WST-8 assay, showed that Se-HA has a cytotoxic effect; however, the co-substitution of strontium in Se-HA offsets the negative impact of selenium and enhanced the biological properties of HA. Hence, the prepared samples are a suitable choice for antibacterial coatings and bone filler applications.

scholarly journals A New Supported Manganese-Based Coordination Complex as a Nano-Catalyst for the Synthesis of Indazolophthalazinetriones and Investigation of Its Antibacterial Activity

Chemistry ◽  
2021 ◽  
Vol 3 (3) ◽  
pp. 783-799
Author(s):  
Maryam Ariannezhad ◽  
Davood Habibi ◽  
Somayyeh Heydari ◽  
Vahideh Khorramabadi
Keyword(s):  
Antibacterial Activity ◽  
Simple Procedure ◽  
Condensation Reaction ◽  
Antibacterial Properties ◽  
Coordination Complex ◽  
Bacterial Strains ◽  
One Pot ◽  
Nano Catalyst ◽  
Ft Ir ◽  
The One

A new magnetic supported manganese-based coordination complex (Fe3O4@SiO2@CPTMS@MBOL@ Mn) was prepared in consecutive stages and characterized via various techniques (VSM, SEM, TEM, XRD, FT-IR, EDX, TG-DTA, and ICP). To evaluate its application, it was used for synthesis of divers Indazolophthalazinetriones in a simple procedure via the one-pot three-component condensation reaction of aldehydes, dimedone, and phthalhydrazide in ethanol under reflux conditions. The Mn catalyst can be recycled without any noticeable loss in catalytic activity. Additionally, the antibacterial properties of the nano-catalyst were studied against some bacterial strains.

Crystal structure of acetylxylan esterase from Caldanaerobacter subterraneus subsp. tengcongensis

2021 ◽  
Vol 77 (11) ◽  
Author(s):  
Kohei Sasamoto ◽  
Tomoki Himiyama ◽  
Kunihiko Moriyoshi ◽  
Takashi Ohmoto ◽  
Koichi Uegaki ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Cellulose Acetate ◽  
Electron Density ◽  
Active Site ◽  
Catalytic Domain ◽  
Crystal Packing ◽  
Signal Sequence ◽  
Industrial Applications ◽  
Side Chain ◽  
Active Site Conformation

The acetylxylan esterases (AXEs) classified into carbohydrate esterase family 4 (CE4) are metalloenzymes that catalyze the deacetylation of acetylated carbohydrates. AXE from Caldanaerobacter subterraneus subsp. tengcongensis (TTE0866), which belongs to CE4, is composed of three parts: a signal sequence (residues 1–22), an N-terminal region (NTR; residues 23–135) and a catalytic domain (residues 136–324). TTE0866 catalyzes the deacetylation of highly substituted cellulose acetate and is expected to be useful for industrial applications in the reuse of resources. In this study, the crystal structure of TTE0866 (residues 23–324) was successfully determined. The crystal diffracted to 1.9 Å resolution and belonged to space group I212121. The catalytic domain (residues 136–321) exhibited a (β/α)7-barrel topology. However, electron density was not observed for the NTR (residues 23–135). The crystal packing revealed the presence of an intermolecular space without observable electron density, indicating that the NTR occupies this space without a defined conformation or was truncated during the crystallization process. Although the active-site conformation of TTE0866 was found to be highly similar to those of other CE4 enzymes, the orientation of its Trp264 side chain near the active site was clearly distinct. The unique orientation of the Trp264 side chain formed a different-shaped cavity within TTE0866, which may contribute to its reactivity towards highly substituted cellulose acetate.

scholarly journals Synthesis and Characterization of a Bioartificial Polymeric System with Potential Antibacterial Activity: Chitosan-Polyvinyl Alcohol-Ampicillin

Molecules ◽  
2018 ◽  
Vol 23 (12) ◽  
pp. 3109 ◽  
Author(s):  
Andres Bernal-Ballen ◽  
Jorge Lopez-Garcia ◽  
Martha-Andrea Merchan-Merchan ◽  
Marian Lehocky
Keyword(s):  
Antibacterial Activity ◽  
Polyvinyl Alcohol ◽  
Statistical Significance ◽  
Antibacterial Properties ◽  
Intermolecular Forces ◽  
Polymeric System ◽  
Bacterial Strains ◽  
Natural Polymers ◽  
The Matrix ◽  
The Individual

Bio-artificial polymeric systems are a new class of polymeric constituents based on blends of synthetic and natural polymers, designed with the purpose of producing new materials that exhibit enhanced properties with respect to the individual components. In this frame, a combination of polyvinyl alcohol (PVA) and chitosan, blended with a widely used antibiotic, sodium ampicillin, has been developed showing a moderate behavior in terms of antibacterial properties. Thus, aqueous solutions of PVA at 1 wt.% were mixed with acid solutions of chitosan at 1 wt.%, followed by adding ampicillin ranging from 0.3 to 1.0 wt.% related to the total amount of the polymers. The prepared bio-artificial polymeric system was characterized by FTIR, SEM, DSC, contact angle measurements, antibacterial activity against Staphylococcus aureus and Escherichia coli and antibiotic release studies. The statistical significance of the antibacterial activity was determined using a multifactorial analysis of variance with ρ < 0.05 (ANOVA). The characterization techniques did not show alterations in the ampicillin structure and the interactions with polymers were limited to intermolecular forces. Therefore, the antibiotic was efficiently released from the matrix and its antibacterial activity was preserved. The system disclosed moderate antibacterial activity against bacterial strains without adding a high antibiotic concentration. The findings of this study suggest that the system may be effective against healthcare-associated infections, a promising view in the design of novel antimicrobial biomaterials potentially suitable for tissue engineering applications.

scholarly journals Antibacterial Activity of Leukocyte- and Platelet-Rich Plasma: AnIn VitroStudy

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Agata Cieślik-Bielecka ◽  
Tadeusz Bold ◽  
Grzegorz Ziółkowski ◽  
Marcin Pierchała ◽  
Aleksandra Królikowska ◽  
...  
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Enterococcus Faecalis ◽  
Platelet Rich Plasma ◽  
Antibacterial Properties ◽  
Antimicrobial Effect ◽  
Diffusion Method ◽  
Bacterial Strains ◽  
Bovine Thrombin ◽  
Zones Of Inhibition

The aim of the study was to investigate the leukocyte- and platelet-rich plasma (L-PRP) antimicrobial activity. The studied sample comprised 20 healthy males. The L-PRP gel, liquid L-PRP, and thrombin samples were testedin vitrofor their antibacterial properties against selected bacterial strains using the Kirby-Bauer disc diffusion method. Two types of thrombin were used (autologous and bovine). Zones of inhibition produced by L-PRP ranged between 6 and 18 mm in diameter. L-PRP inhibited the growth ofStaphylococcus aureus(MRSA and MSSA strains) and was also active againstEnterococcus faecalisandPseudomonas aeruginosa. There was no activity againstEscherichia coliandKlebsiella pneumoniae. The statistically significant increase of L-PRP antimicrobial effect was noted with the use of major volume of thrombin as an activator. Additionally, in groups where a bovine thrombin mixture was added to L-PRP the zones of inhibition concerning MRSA,Enterococcus faecalis, andPseudomonas aeruginosawere larger than in the groups with autologous thrombin. Based on the conducted studies, it can be determined that L-PRP can evokein vitroantimicrobial effects and might be used to treat selected infections in the clinical field. The major volume of thrombin as an activator increases the strength of the L-PRP antimicrobial effect.

scholarly journals The Crystal Structure of Shikimate Dehydrogenase (AroE) Reveals a Unique NADPH Binding Mode

2003 ◽  
Vol 185 (14) ◽  
pp. 4144-4151 ◽  
Author(s):  
Sheng Ye ◽  
Frank von Delft ◽  
Alexei Brooun ◽  
Mark W. Knuth ◽  
Ronald V. Swanson ◽  
...  
Keyword(s):  
Catalytic Domain ◽  
Binding Pocket ◽  
Binding Mode ◽  
Sequence Motif ◽  
Binary Complex ◽  
Shikimate Dehydrogenase ◽  
Conserved Residues ◽  
Conserved Sequence ◽  
Nicotinamide Mononucleotide ◽  
Reversible Reduction

ABSTRACT Shikimate dehydrogenase catalyzes the NADPH-dependent reversible reduction of 3-dehydroshikimate to shikimate. We report the first X-ray structure of shikimate dehydrogenase from Haemophilus influenzae to 2.4-Å resolution and its complex with NADPH to 1.95-Å resolution. The molecule contains two domains, a catalytic domain with a novel open twisted α/β motif and an NADPH binding domain with a typical Rossmann fold. The enzyme contains a unique glycine-rich P-loop with a conserved sequence motif, GAGGXX, that results in NADPH adopting a nonstandard binding mode with the nicotinamide and ribose moieties disordered in the binary complex. A deep pocket with a narrow entrance between the two domains, containing strictly conserved residues primarily contributed by the catalytic domain, is identified as a potential 3-dehydroshikimate binding pocket. The flexibility of the nicotinamide mononucleotide portion of NADPH may be necessary for the substrate 3-dehydroshikimate to enter the pocket and for the release of the product shikimate.

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