scholarly journals Agrobacterium fabrumatu0526-Encoding Protein Is the Only Chemoreceptor That Regulates Chemoattraction toward the Broad Antibacterial Agent Formic Acid

Biology ◽  
2021 ◽  
Vol 10 (12) ◽  
pp. 1345
Author(s):  
Hao Wang ◽  
Mengqi Zhang ◽  
Yujuan Xu ◽  
Renjie Zong ◽  
Nan Xu ◽  
...  
Keyword(s):  
Formic Acid ◽  
Antibacterial Agent ◽  
Plant Pathogens ◽  
3D Structure ◽  
Antimicrobial Properties ◽  
Titration Calorimetry ◽  
Knock Out ◽  
In Vivo Experiments ◽  
Encoding Protein

Soil-born plant pathogens, especially Agrobacterium, generally navigate their way to hosts through recognition of the root exudates by chemoreceptors. However, there is still a lack of appropriate identification of chemoreceptors and their ligands in Agrobacterium. Here, Atu0526, a sCache-type chemoreceptor from Agrobacterium fabrum C58, was confirmed as the receptor of a broad antibacterial agent, formic acid. The binding of formic acid to Atu0526 was screened using a thermo shift assay and verified using isothermal titration calorimetry. Inconsistent with the previously reported antimicrobial properties, formic acid was confirmed to be a chemoattractant to A. fabrum and could promote its growth. The chemotaxis of A. fabrum C58 toward formic acid was completely lost with the knock-out of atu0526, and regained with the complementation of the gene, indicating that Atu0526 is the only chemoreceptor for formic acid in A. fabrum C58. The affinity of formic acid to Atu0526LBD significantly increased after the arginine at position 115 was replaced by alanine. However, in vivo experiments showed that the R115A mutation fully abolished the chemotaxis of A. fabrum toward formic acid. Molecular docking based on a predicted 3D structure of Atu0526 suggested that the arginine may provide “an anchorage” for formic acid to pull the minor loop, thereby forming a conformational change that generates the ligand-binding signal. Collectively, our findings will promote an understanding of sCache-type chemoreceptors and their signal transduction mechanism.

scholarly journals The Extracellular Small Leucine-Rich Proteoglycan Biglycan Is a Key Player in Gastric Cancer Aggressiveness

Cancers ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 1330
Author(s):  
Filipe Pinto ◽  
Liliana Santos-Ferreira ◽  
Marta T. Pinto ◽  
Catarina Gomes ◽  
Celso A. Reis
Keyword(s):  
Clinical Value ◽  
Knock Out ◽  
Angiogenic Potential ◽  
In Vivo Experiments ◽  
Cancer Aggressiveness ◽  
Advanced Stages ◽  
Oncogenic Gene

Biglycan (BGN gene), an extracellular proteoglycan, has been described to be associated with cancer aggressiveness. The purpose of this study was to clarify the clinical value of biglycan as a biomarker in multiple independent GC cohorts and determine the in vitro and in vivo role of biglycan in GC malignant features. We found that BGN is commonly over-expressed in all analyzed cohorts, being associated with disease relapse and poor prognosis in patients with advanced stages of disease. In vitro and in vivo experiments demonstrated that biglycan knock-out GC cells display major phenotypic changes with a lower cell survival, migration, and angiogenic potential when compared with biglycan expressing cells. Biglycan KO GC cells present increased levels of PARP1 and caspase-3 cleavage and a decreased expression of mesenchymal markers. Importantly, biglycan deficient GC cells that were supplemented with exogenous biglycan were able to restore biological features, such as survival, clonogenic and migratory capacities. Our in vitro and in vivo findings were validated in human GC samples, where BGN expression was associated with several oncogenic gene signatures that were associated with apoptosis, cell migration, invasion, and angiogenesis. This study provided new insights on biglycan role in GC that should be taken in consideration as a key cellular regulator with major impact in tumor progression and patients’ clinical outcome.

4966Targeting INaL by a neuronal sodium channel isoform improves survival in a CaMKII-transgenic heart failure mouse model

2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
P Bengel ◽  
C Krekeler ◽  
S Ahmad ◽  
P Tirilomis ◽  
K Toischer ◽  
...  
Keyword(s):  
Heart Failure ◽  
Mouse Model ◽  
Sodium Channel ◽  
Sodium Current ◽  
Heart Weight ◽  
Knock Out ◽  
In Vivo Experiments ◽  
Antiarrhythmic Effects

Abstract Background Cardiac pathologies like hypertrophy and heart failure are known to be associated with proarrhythmogenic triggers like early- (EADs) and delayed afterdepolarizations (DADs) that can be partly attributed to an augmentation of late sodium current (INaL). Enhanced INaL is closely connected with increased activity of Ca2+/calmodulin dependent-kinase II (CaMKII) in pathology as it is enhanced by CaMKII on the one hand but can also indirectly increase CaMKII-activity on the other. We recently found neuronal sodium channel NaV1.8 to be involved in INaL-augmentation in heart failure and cardiac hypertrophy. Here, we studied possible antiarrhythmic effects of NaV1.8-inhibition in a transgenic mouse model with enhanced CaMKII-expression by selectively knocking out NaV1.8. Methods/Results To investigate antiarrhythmic effects of NaV1.8-depletion in-vivo and in-vitro we crossbred CaMKII-transgenic mice (CaMKII+/T) with NaV1.8-knock-out mice (SCN10A−/−). Surprisingly, CaMKII+/T-mice lacking NaV1.8 (CaMKII+/T & SCN10A−/−) showed a significantly improved survival compared to CaMKII+/T alone (97.5 vs 72.0 days, p<0.05). Heart weight to tibia length ratio was significantly increased in CaMKII+/T-mice compared to wild-type, without any differences between CaMKII+/T and CaMKII+/T & SCN10A−/−. To investigate the underlying mechanisms out of this observation we isolated single cardiomyocytes and performed patch-clamp experiments as well as confocal microscopy to measure Ca2+-transients and diastolic Ca2+-waves. INaL-integral was significantly smaller in cardiomyocytes from CaMKII+/T & SCN10A−/−-mice compared to CaMKII+/T alone. During action potential recordings, significantly less afterdepolarizations occurred in CaMKII+/T & SCN10A−/− compared to cardiomyocytes from CaMKII+/T -mice (16.7/min vs 34.9/min, p<0.05). There was a trend of less cells exhibiting diastolic Ca2+-waves in Ca2+-measurements from CaMKII+/T & SCN10A−/− compared to CaMKII+/T (15% vs 25%, p=0.09). As some cells showed more than one event, we calculated the frequency of Ca2+-waves and found a significant reduction of Ca2+-waves in CaMKII+/T & SCN10A−/− vs. CaMKII+/T (22.8/min vs 43.0/min, p<0.05). Moreover, the time to the first event was significantly longer in CaMKII+/T & SCN10A−/−. Ca2+-transient amplitude (F/F0) was significantly lower in CaMKII+/T compared to CaMKII+/T & SCN10A−/− (4.6 vs. 5.3, p=0.05). Further, Ca2+-extrusion from the cytosol was significantly faster in CaMKII+/T & SCN10A−/−. Conclusion Our data demonstrates, that inhibition of INaL by targeting NaV1.8 has a potent antiarrhythmic potential as we found a reduction of EADs, DADs and diastolic Ca2+-waves in CaMKII+/T & SCN10A−/−-cardiomyocytes. This antiarrhythmic potential appears to be potent enough to improve survival and to rescue the proarrhythmogenic phenotype of CaMKII-overexpression. However, further in-vivo experiments are necessary to investigate NaV1.8-inhibition for a possible therapeutic approach.

scholarly journals Antibacterial properties of thioridazine

2019 ◽  
pp. 96-104
Author(s):  
N. Hrynchuk ◽  
N. Vrynchanu
Keyword(s):  
Antibacterial Activity ◽  
Ex Vivo ◽  
Antibacterial Properties ◽  
Antimicrobial Properties ◽  
Antibiotic Resistant ◽  
In Vivo Experiments ◽  
Antistaphylococcal Activity ◽  
The Impact

The emergence and spread of antibiotic-resistant strains of microorganisms reduces the effectiveness of antibiotic therapy and requires finding solutions to problems, one of which is the study of antimicrobial properties in drugs of various pharmacological groups. The purpose of the work was to summarize the data on the antibacterial activity of thioridazine and its derivatives to determine the feasibility and prospects of creating new antibacterial drugs on their basis. The paper presents literature data on the effects of thioridazine on the causative agent of tuberculosis, antistaphylococcal activity, susceptibility of plasmodium and trypanosoma. The antibacterial activity of the drug was established within in vitro studies with the determination of MIC towards gram-positive and gram-negative microorganisms, ex vivo using macrophage lines, as well as within in vivo experiments on mice. It is established that the neuroleptic thioridazine is characterized by pronounced anti-tuberculosis activity, the mechanism of action is associated with the impact on the cell membrane of M. tuberculosis, inactivation by calmodulin and inhibition of specific NADH-dehydrogenase type II. The literature data indicate that thioridazine is able to increase the activity of isoniazid against the strains of mycobacteria that are susceptible and resistant to its action. It has been established that resistance to thioridazine in antibiotic-resistant M. tuberculosis strains is not formed. The drug is characterized by its ability to inhibit the growth and reproduction of both methicylin-sensitive (MSSA) and methicilin-resistant (MRSA) strains of Staphylococcus aureus, which has been proven within in vitro experiments. The effectiveness of thioridazine has been proven within in vivo experiments in case of skin infection and sepsis caused by S. aureus. Antimicrobial effect of the drug is also observed towards to plasmodium (P. falciparum) and trypanosomes (Trypanosoma spp.). Currently, the synthesis of thioridazine derivatives is carried out to identify compounds with a pronounced antibacterial effect. Some of the first synthesized compounds are not inferior or superior to thioridazine by the inhibitory effect. Thus, these data suggest that drugs of different pharmacological groups, including drugs that affect the nervous system - thioridazine and its derivatives, can be a source of replenishment of the arsenal of antimicrobial drugs to control such threatening infections as tuberculosis and diseases caused by polyresistant strains of microorganisms.

scholarly journals Overexpression of the Synthetic Chimeric Native-T-phylloplanin-GFP Genes Optimized for Monocot and Dicot Plants Renders Enhanced Resistance to Blue Mold Disease in Tobacco (N. tabacumL.)

2014 ◽  
Vol 2014 ◽  
pp. 1-12 ◽  
Author(s):  
Dipak K. Sahoo ◽  
Sumita Raha ◽  
James T. Hall ◽  
Indu B. Maiti
Keyword(s):  
Plant Pathogens ◽  
Fluorescent Microscopy ◽  
Antimicrobial Properties ◽  
Chimeric Gene ◽  
Protein Fusion ◽  
Blue Mold ◽  
Gfp Gene ◽  
Transgenic Lines ◽  
Full Length Transcript

To enhance the natural plant resistance and to evaluate the antimicrobial properties of phylloplanin against blue mold, we have expressed a synthetic chimeric native-phylloplanin-GFP protein fusion in transgenicNicotiana tabacumcv. KY14, a cultivar that is highly susceptible to infection byPeronospora tabacina. The coding sequence of the tobacco phylloplanin gene along with its native signal peptide was fused with GFP at the carboxy terminus. The synthetic chimeric gene (native-phylloplanin-GFP) was placed between the modifiedMirabilis mosaic virusfull-length transcript promoter with duplicated enhancer domains and the terminator sequence from the rbcSE9 gene. The chimeric gene, expressed in transgenic tobacco, was stably inherited in successive plant generations as shown by molecular characterization, GFP quantification, and confocal fluorescent microscopy. Transgenic plants were morphologically similar to wild-type plants and showed no deleterious effects due to transgene expression. Blue mold-sensitivity assays of tobacco lines were performed by applyingP. tabacinasporangia to the upper leaf surface. Transgenic lines expressing the fused synthetic native-phyllopanin-GFP gene in the leaf apoplast showed resistance to infection. Our results demonstrate thatin vivoexpression of a synthetic fused native-phylloplanin-GFP gene in plants can potentially achieve natural protection against microbial plant pathogens, includingP. tabacinain tobacco.

scholarly journals Effects of developed thyme and oregano essential oil formulations on Monilinia laxa and Monilinia fructicola

2020 ◽  
Vol 35 (1) ◽  
pp. 49-56
Author(s):  
Brankica Tanovic ◽  
Jovana Hrustic ◽  
Milica Mihajlovic ◽  
Mila Grahovac ◽  
Marija Stevanovic ◽  
...  
Keyword(s):  
Essential Oil ◽  
Essential Oils ◽  
Antimicrobial Properties ◽  
Monilinia Fructicola ◽  
Monilinia Laxa ◽  
Oregano Essential Oil ◽  
In Vivo Experiments ◽  
Apple Fruits

Essential oils have been well-known for their antimicrobial properties for a very long time. Some of them have been effectively used in human medicine for decades. Our earlier investigation revealed a great potential of thyme and oregano essential oils as crop protectants against some postharvest fruit pathogens. The effects of formulated thyme and oregano essential oils on Monilinia laxa and Monilinia fructicola were studied in vitro and in vivo. In vitro antagonistic assays were performed on solidified PDA medium using a slightly modified agar overlay technique, while in vivo experiments were conducted on inoculated apple fruits. In vitro essays showed that the developed formulations (emulsifiable concentrates - EC) significantly inhibited the mycelial growth of Monilinia spp. Experiments in vivo, performed on inoculated apple fruits, revealed that the developed formulations provided a significant level of Monilinia spp. suppression. To our knowledge, another EC formulation of oregano essential oil intended for use in Monilinia spp. control has never been developed before. The presented results are initial findings and evaluation of the activity of the developed products should therefore proceed under field conditions to determine their efficacy and activity spectrum, and to estimate economic aspects of their use.

scholarly journals Fabrication of Subretinal 3D Microelectrodes with Hexagonal Arrangement

Micromachines ◽  
2020 ◽  
Vol 11 (5) ◽  
pp. 467 ◽  
Author(s):  
Hee Won Seo ◽  
Namju Kim ◽  
Sohee Kim
Keyword(s):  
Integrated Circuit ◽  
Microelectrode Array ◽  
3D Structure ◽  
Three Dimensional ◽  
Active Electrode ◽  
Prosthetic Devices ◽  
In Vivo Experiments ◽  
Hexagonal Arrangement

This study presents the fabrication of three-dimensional (3D) microelectrodes for subretinal stimulation, to accommodate adjacent return electrodes surrounding a stimulating electrode. For retinal prosthetic devices, the arrangement of return electrodes, the electrode size and spacing should be considered together, to reduce the undesired dissipation of electric currents. Here, we applied the hexagonal arrangement to the microelectrode array for the localized activation of retinal cells and better visual acuity. To provide stimuli more efficiently to non-spiking neurons, a 3D structure was created through a customized pressing process, utilizing the elastic property of the materials used in the fabrication processes. The diameter and pitch of the Pt-coated electrodes were 150 μm and 350 μm, respectively, and the height of the protruded electrodes was around 20 μm. The array consisted of 98 hexagonally arranged electrodes, supported by a flexible and transparent polydimethylsiloxane (PDMS) base, with a thickness of 140 μm. Also, the array was coated with 2 μm-thick parylene-C, except the active electrode sites, for more focused stimulation. Finally, the electrochemical properties of the fabricated microelectrodes were characterized, resulting in the mean impedance of 384.87 kΩ at 1 kHz and the charge storage capacity (CSC) of 2.83 mC·cm−2. The fabricated microelectrodes are to be combined with an integrated circuit (IC) for additional in vitro and in vivo experiments.

scholarly journals Antimicrobial Properties of Apis mellifera’s Bee Venom

Toxins ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 451 ◽  
Author(s):  
Hesham El-Seedi ◽  
Aida Abd El-Wahed ◽  
Nermeen Yosri ◽  
Syed Ghulam Musharraf ◽  
Lei Chen ◽  
...  
Keyword(s):  
Antimicrobial Properties ◽  
Bee Venom ◽  
Biological Functions ◽  
Volatile Metabolites ◽  
In Vivo Experiments ◽  
Anticancer Effects ◽  
Bioactive Ingredients ◽  
The Impact

Bee venom (BV) is a rich source of secondary metabolites from honeybees (Apis mellifera L.). It contains a variety of bioactive ingredients including peptides, proteins, enzymes, and volatile metabolites. The compounds contribute to the venom’s observed biological functions as per its anti-inflammatory and anticancer effects. The antimicrobial action of BV has been shown in vitro and in vivo experiments against bacteria, viruses, and fungi. The synergistic therapeutic interactions of BV with antibiotics has been reported. The synergistic effect contributes to a decrease in the loading and maintenance dosage, a decrease in the side effects of chemotherapy, and a decrease in drug resistance. To our knowledge, there have been no reviews on the impact of BV and its antimicrobial constituents thus far. The purpose of this review is to address the antimicrobial properties of BV and its compounds.

scholarly journals Detrimental proarrhythmogenic interaction of Ca2+/calmodulin-dependent protein kinase II and NaV1.8 in heart failure

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Philipp Bengel ◽  
Nataliya Dybkova ◽  
Petros Tirilomis ◽  
Shakil Ahmad ◽  
Nico Hartmann ◽  
...  
Keyword(s):  
Heart Failure ◽  
Protein Kinase ◽  
Direct Interaction ◽  
Dependent Protein Kinase ◽  
Knock Out ◽  
Downstream Target ◽  
In Vivo Experiments ◽  
Dependent Protein ◽  
Human Ipsc

AbstractAn interplay between Ca2+/calmodulin-dependent protein kinase IIδc (CaMKIIδc) and late Na+ current (INaL) is known to induce arrhythmias in the failing heart. Here, we elucidate the role of the sodium channel isoform NaV1.8 for CaMKIIδc-dependent proarrhythmia. In a CRISPR-Cas9-generated human iPSC-cardiomyocyte homozygous knock-out of NaV1.8, we demonstrate that NaV1.8 contributes to INaL formation. In addition, we reveal a direct interaction between NaV1.8 and CaMKIIδc in cardiomyocytes isolated from patients with heart failure (HF). Using specific blockers of NaV1.8 and CaMKIIδc, we show that NaV1.8-driven INaL is CaMKIIδc-dependent and that NaV1.8-inhibtion reduces diastolic SR-Ca2+ leak in human failing cardiomyocytes. Moreover, increased mortality of CaMKIIδc-overexpressing HF mice is reduced when a NaV1.8 knock-out is introduced. Cellular and in vivo experiments reveal reduced ventricular arrhythmias without changes in HF progression. Our work therefore identifies a proarrhythmic CaMKIIδc downstream target which may constitute a prognostic and antiarrhythmic strategy.

scholarly journals Synthesis and antibacterial activity of 3-arylaminomethyl-1-(2-oxo-2-arylethyl)-6,7,8,9-tetrahydro-5H-[1,2,4]triazolo[4,3-a] azepin-1-ium bromides and aryl-(4-R1-phenyl-5,6,7,8-tetrahydro-2,2a,8a-triazacyclopenta[cd]azulen-1-ylmethyl)-amines

2021 ◽  
pp. 51-57
Author(s):  
Nataliya Demchenko ◽  
Zinaida Suvorova ◽  
Yuliia Fedchenkova ◽  
Tamara Shpychak ◽  
Oleh Shpychak ◽  
...  
Keyword(s):  
Antimicrobial Activity ◽  
Antimicrobial Properties ◽  
Antimicrobial Drugs ◽  
Reference Drug ◽  
Gram Negative ◽  
In Vivo Experiments ◽  
Yeast Fungi ◽  
Methods Of Synthesis ◽  
Bacteria And Fungi

The aim of this work is to develop methods of synthesis of 3-arylaminomethyl-1-(2-oxo-2-arylethyl)-6,7,8,9-tetrahydro-5H-[1,2,4]triazolo[4,3-a]azepin-1-ium bromides and aryl-(4-R1-phenyl-5,6,7,8-tetrahydro-2,2a,8a-triazacyclopenta[cd]azulen-1-ylmethyl)-amines and to study their antimicrobial activity against strains of gram-positive and gram-negative bacteria as well as yeast fungi. Materials and methods. 1Н NMR spectra were recorded on Bruker 400 spectrometer operating at frequency of 400 MHz. Antimicrobial activity of the compounds synthesized was evaluated by their minimum inhibitory concentration (MIC) values. Results and discussion. The interaction of 3-arylaminomethyl-6,7,8,9-tetrahydro-5H-[1,2,4]triazolo[4,3-a]azepines with substituted phenacyl bromides produced novel 3-arylaminomethyl-1-(2-oxo-2-arylethyl)-6,7,8,9-tetrahydro-5H-[1,2,4]triazolo[4,3-a]azepin-1-ium bromides. The latter when refluxed in 10 % solution of NaOH gave aryl-(4-R1-phenyl-5,6,7,8-tetrahydro-2,2a,8a-triazacyclopenta[cd]azulen-1-ylmethyl)-amines. The study of antimicrobial activity of the compounds obtained allowed to find derivatives which are active against С. albicans and S. aureus strains. Among the compounds tested 3-[(41-bromophenylamino)-methyl]-1-[2-(4-methoxyphenyl)-2-oxoethyl]-6,7,8,9-tetrahydro-5H-[1,2,4]triazolo[4,3-a]azepin-1-ium bromide 5cd appeared to be more active than the reference drug Cefixime and displayed close antimicrobial activity as the antibiotic Linezolid. Conclusions. It was found out that derivatives of 3-arylaminomethyl-1-(2-oxo-2-arylethyl)-6,7,8,9-tetrahydro-5H-[1,2,4]triazolo[4,3-a]azepin-1-ium bromides display broad spectrum of antimicrobial activity and are able to inhibit growth of both bacteria and fungi. S. aureus and C. albicans turned out to be the most sensitive strains to the compounds tested, MIC was in the range of 6.2-25.0 mg/mL. Gram-negative strains of microorganisms were less sensitive to the compounds evaluated and 5fа was the most active derivative displaying antimicrobial activity at the concentration of 50.0 mg/mL. Antimicrobial activity of triazoloazepinium bromide derivatives was similar to that one of Linezolid and Fluconazole reference drugs and more pronounced than the activity of Cefixime. Hence, the data gathered evidence the feasibility of further study of the antimicrobial properties of the most active compounds in in vivo experiments aiming at assessment of the prospects for the creation of new effective and safe antimicrobial drugs based on them

scholarly journals Multiclawed SiO2 Nano-Antibacterial Agent Based on Charge Inversed Ce6 Ionic Liquid Polymers for Combating Oral Biofilm Infection

2022 ◽  
Vol 2022 ◽  
pp. 1-10
Author(s):  
Ziyi Jiao ◽  
Yonggang Teng ◽  
Chunjing Zhan ◽  
Youbei Qiao ◽  
Yuying Ma ◽  
...  
Keyword(s):  
Ionic Liquid ◽  
Antibacterial Agent ◽  
Infection Site ◽  
Oral Biofilm ◽  
In Vivo Experiments ◽  
Liquid Polymers ◽  
Poly Ionic Liquid ◽  
Biofilm Infection

Photodynamic antimicrobial chemotherapy (PACT) is a promising therapy against biofilm infection. However, due to the saliva clearance and obstacle of biofilm, the photosensitizer is difficult to concentrate in the infection site; then, the PACT is less effective on oral biofilm infection. In this article, we report a special nano-antibacterial agent (SiO2-PCe6-IL) to solve the bottleneck problem of PACT in treatment of oral biofilm infections. The SiO2-PCe6-IL was composed of SiO2 and poly ionic liquid photosensitizer (PCe6-IL) and had tri-fold features of eliminate biofilm infection: high binding ability, breaking biofilm barriers, and enrichment photosensitizer in infection site. In oral biofilm, the SiO2-PCe6-IL changed to SiO2-PIL+ like claws of octopus that could hold tightly with biofilm. Then, the poly-dodecyl on the SiO2-PIL+ broke down the barrier of biofilm. The results of HR-MS and zeta potential indicated that SiO2-PCe6-IL could change to positive (SiO2-PIL+) in acidic environment. The interaction forces and morphology results proved that the SiO2-PIL+ had a higher affinity to biofilm and could destroy the biofilm structure. Then, the photosensitizer was enriched in biofilm at sites of infection. The in vitro and in vivo experiments showed that SiO2-PCe6-IL could effectively eradicate oral biofilm infections and control of dental caries.

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