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The difference on inhibitory effects of bioflavonoids inhibiting XOD activity assayed by varying test methods cause of us to be further in consideration. The reported test method creating a micro‐environment surrounding XOD in the absence of ⋅O2−, which is seemly different from the assay in vivo. So, the vitro test method for assaying XOD activity is necessary to be improved for selection of potential inhibitors in the presence of ⋅O2−. The inhibitory results demonstrated that bioflavonoids of MY, DMY, QUE and LUT are capable to be on effective IC50 values, but others are not. As well, their resulting inhibitions determined by the improved test method are much less than that reported in the literature, indicating that their chemical affinities with XOD become weaker. Moreover, DMY assayed on the inhibitions of XOD in the improved test method performs to be a better inhibitor, as compared to the assay of the reported test methods. Abasing on the transformation of DMY into MY in the presence of ⋅O2−, the good inhibition of DMY on XOD activity can be explained by the synergistic effect of MY. [ABSTRACT FROM AUTHOR]

Antibiotics are currently used for the treatment of Helicobacter pylori (H. pylori), which is confirmed to be the major cause of gastric disorders. However, the long-term consumption of antibiotics has already caused antibiotic resistance and side effects in vivo. Therefore, there is an emerging need for searching for safe and effective anti-H. pylori agents. Inspired by the excellent bioactivities of cinnamic acid, a series of cinnamic acid derivatives (compounds 1–30) were synthesized and determined for H. pylori inhibition. The initial screening revealed that compound 23, a 2,4-dinitro cinnamic acid derivative containing 4-methoxyphenol, showed excellent H. pylori inhibition with an MIC value of 4 μM. Further studies indicated that compound 23 showed anti-bacterial activity and had a bactericidal effect on H. pylori due to the destruction of the bacterial structure. Molecular docking analysis revealed that the 2,4-dinitro groups in cinnamic acid moiety formed hydrogen bonding with amino acid residues in an active pocket of H. pylori protein. Interestingly, the ester moiety fitted into the hydrophobic pocket, attaining additional stability to compound 23. Above all, the present study reveals that compound 23 could be considered a promising anti-H. pylori agent to treat H. pylori causing gastritis. [ABSTRACT FROM AUTHOR]

Abstract Background Zika virus (ZIKV) and dengue virus (DENV) cause microcephaly and dengue hemorrhagic fever, respectively, leading to severe problems. No effective antiviral agents are approved against infections of these flaviviruses, calling for the need to develop potent therapeutics. We previously identified gossypol as an effective inhibitor against ZIKV and DENV infections, but this compound is toxic and not suitable for in vivo treatment. Results In this study, we showed that gossypol derivative ST087010 exhibited potent and broad-spectrum in vitro inhibitory activity against infections of at least ten ZIKV strains isolated from different hosts, time periods, and countries, as well as DENV-1-4 serotypes, and significantly reduced cytotoxicity compared to gossypol. It presented broad-spectrum in vivo protective efficacy, protecting ZIKV-infected Ifnar1 −/− mice from lethal challenge, with increased survival and reduced weight loss. Ifnar1 −/− mice treated with this gossypol derivative decreased viral titers in various tissues, including the brain and testis, after infection with ZIKV at different human isolates. Moreover, ST087010 potently blocked ZIKV vertical transmission in pregnant Ifnar1 −/− mice, preventing ZIKV-caused fetal death, and it was safe for pregnant mice and their pups. It also protected DENV-2-challenged Ifnar1 −/− mice against viral replication by reducing the viral titers in the brain, kidney, heart, and sera. Conclusions Overall, our data indicate the potential for further development of this gossypol derivative as an effective and safe broad-spectrum therapeutic agent to treat ZIKV and DENV diseases.

Campylobacter is a major cause of acute human diarrheal illness. Broiler chickens constitute a primary reservoir for C. jejuni leading to human infection. Consequently, there is a need for developing novel intervention methods. Antimicrobial peptides (AMP) are small proteins which have evolved in most lifeforms to provide defense against microbial infections. To date, over 3000 AMP have been discovered; however, few of them have been analyzed specifically for ability to kill campylobacters. We selected and evaluated a set of 11 unique chemically synthesized AMP for ability to inhibit growth of C. jejuni. Six of the AMP we tested produced zones of inhibition on lawns of C. jejuni. These AMP included: NRC-13, RL-37, Temporin L, Cecropin–Magainin, Dermaseptin, and C12K-2β12. In addition, MIC were determined for Cecropin–Magainin, RL-37 and C12K-2β12 against 15 isolates of Campylobacter representing the three most common pathogenic strains. MIC for campylobacters were approximately 3.1 µg/mL for AMP RL-37 and C12K-2β12. MIC were slightly higher for the Cecropin–Magainin AMP in the range of 12.5 to 100 µg/mL. These AMP are attractive subjects for future study and potential in vivo delivery to poultry to reduce Campylobacter spp. populations. [ABSTRACT FROM AUTHOR]

Background: Zika virus (ZIKV) and dengue virus (DENV) cause microcephaly and dengue hemorrhagic fever, respectively, leading to severe problems. No effective antiviral agents are approved against infections of these flaviviruses, calling for the need to develop potent therapeutics. We previously identified gossypol as an effective inhibitor against ZIKV and DENV infections, but this compound is toxic and not suitable for in vivo treatment. Results: In this study, we showed that gossypol derivative ST087010 exhibited potent and broad-spectrum in vitro inhibitory activity against infections of at least ten ZIKV strains isolated from different hosts, time periods, and countries, as well as DENV-1-4 serotypes, and significantly reduced cytotoxicity compared to gossypol. It presented broad-spectrum in vivo protective efficacy, protecting ZIKV-infected Ifnar1−/− mice from lethal challenge, with increased survival and reduced weight loss. Ifnar1−/− mice treated with this gossypol derivative decreased viral titers in various tissues, including the brain and testis, after infection with ZIKV at different human isolates. Moreover, ST087010 potently blocked ZIKV vertical transmission in pregnant Ifnar1−/− mice, preventing ZIKV-caused fetal death, and it was safe for pregnant mice and their pups. It also protected DENV-2-challenged Ifnar1−/− mice against viral replication by reducing the viral titers in the brain, kidney, heart, and sera. Conclusions: Overall, our data indicate the potential for further development of this gossypol derivative as an effective and safe broad-spectrum therapeutic agent to treat ZIKV and DENV diseases. [ABSTRACT FROM AUTHOR]

We report the production and biochemical characterization of an α-carbonic anhydrase (LrhCA) from gram-positive probiotic bacteria Lactobacillus rhamnosus GG. CAs form a family of metalloenzymes that catalyze hydration of CO2/interconversion between CO2 and water to bicarbonate ions and protons. They are divided into eight independent gene families (α, β, γ, δ, ζ, η, θ, and ι). Interestingly, many pathogens have been identified with only β- and/or γ-CAs, which can be targeted with CA-specific inhibitors (CAIs) acting as anti-pathogen drugs. Since it is important to study the potential off-target effects of CAIs for both the human body and its commensal bacteria, we took L. rhamnosus GG as our study subject. To date, only a single α-CA has been identified in L. rhamnosus GG, which was successfully produced and biochemically characterized. LrhCA showed moderate catalytic activity with the following kinetic parameters: kcat of 9.86 × 105 s−1 and kcat/KM of 1.41 × 107 s−1 M−1. Moderate inhibition was established with 11 of the 39 studied sulfonamides. The best inhibitors were 5-((4-aminophenyl)sulfonamido)-1,3,4-thiadiazole-2-sulfonamide, 4-(2-hydroxymethyl-4-nitrophenyl-sulfonamidoethyl)-benzenesulfonamide, and benzolamide with Ki values of 319 nM, 378 nM, and 387 nM, respectively. The other compounds showed weaker inhibitory effects. The Ki of acetazolamide, a classical CAI, was 733 nM. In vitro experiments with acetazolamide showed that it had no significant effect on cell growth in L. rhamnosus GG culture. Several sulfonamides, including acetazolamide, are in use as clinical drugs, making their inhibition data highly relevant to avoid any adverse off-target effects towards the human body and its probiotic organisms. Key points: • The α-carbonic anhydrase from Lactobacillus rhamnosus GG (LrhCA) is 24.3 kDa. • LrhCA has significant catalytic activity with a kcat of 9.9 × 105 s-1. • Acetazolamide resulted in a marginal inhibitory effect on cell growth. [ABSTRACT FROM AUTHOR]

Abstract Background The frequent usage of broad-spectrum insecticides like cypermethrin in agriculture activities could lead to the development of resistance in insects like Amsacta albistriga. Objectives The present study was conducted to understand the toxicity of cypermethrin with and without a combination of three enzyme inhibitors (PBO, DEM, and TPP) on A. albistriga using a topical bioassay. Methodology The in vitro and in vivo studies were conducted to understand the effect of three enzyme inhibitors such as piperonyl butoxide (PBO) and diethyl maleate (DEM) and triphenyl phosphate along with six different concentration of cypermethrin on the activities of acetylcholinesterase (AChE), esterase (EST), glutathione S-transferase (GST), and mixed-function oxidase (MFO) of A. albistriga. Results Bioassay shows elevated LC50 for cypermethrin (63.32 ppm) whereas in a combination of PBO cypermethrin LC50 values were reduced into 12.039 ppm followed by TPP combination as 13.234 ppm. In vitro and in vivo inhibition analysis shows AChE inhibition by PBO P < 0.01, esterase inhibition by PBO, and TPP were less; GST inhibition by DEM was observed at P < 0.001. Native PAGE results revealed that the in vitro AChE isoenzyme inhibition could be possible by PBO synergism with cypermethrin in A. albistriga. Conclusions The overall results conclude that the PBO and TPP enzyme inhibitors could be fine synergist molecules when it mixed with cypermethrin insecticide to control and manage the insecticide-resistant Amsacta albistriga in the field.

We investigated a panel of 14 compounds belonging to the monothiocarbamate (MTC) and dithiocarbamate (DTC) series against the β-carbonic anhydrase 3 (β-CA3) of Mycobacterium tuberculosis (Mtb). We also evaluated all compounds for toxicity using 1–5-day post fertilisation zebrafish embryos. 11 out of the 14 investigated derivatives showed effective nanomolar or submicromolar in vitro inhibition against the β-CA3 (KIs 2.4–812.0 nM), and among them four DTCs of the series (8–10 and 12) showed very significant inhibition potencies with KIs between 2.4 and 43 nM. Out of 14 compounds screened for toxicity and safety 9 compounds showed no adverse phenotypic effects on the developing zebrafish larvae at five days of exposure. The results of in vitro inhibition and the toxicological evaluation of our study suggest that 5 compounds are suitable for further in vivo preclinical characterisation in zebrafish model.

We investigated a panel of 14 compounds belonging to the monothiocarbamate (MTC) and dithiocarbamate (DTC) series against the β-carbonic anhydrase 3 (β-CA3) of Mycobacterium tuberculosis (Mtb). We also evaluated all compounds for toxicity using 1–5-day post fertilisation zebrafish embryos. 11 out of the 14 investigated derivatives showed effective nanomolar or submicromolar in vitro inhibition against the β-CA3 (KIs 2.4–812.0 nM), and among them four DTCs of the series (8–10 and 12) showed very significant inhibition potencies with KIs between 2.4 and 43 nM. Out of 14 compounds screened for toxicity and safety 9 compounds showed no adverse phenotypic effects on the developing zebrafish larvae at five days of exposure. The results of in vitro inhibition and the toxicological evaluation of our study suggest that 5 compounds are suitable for further in vivo preclinical characterisation in zebrafish model. [ABSTRACT FROM AUTHOR]

Background: The frequent usage of broad-spectrum insecticides like cypermethrin in agriculture activities could lead to the development of resistance in insects like Amsacta albistriga. Objectives: The present study was conducted to understand the toxicity of cypermethrin with and without a combination of three enzyme inhibitors (PBO, DEM, and TPP) on A. albistriga using a topical bioassay. Methodology: The in vitro and in vivo studies were conducted to understand the effect of three enzyme inhibitors such as piperonyl butoxide (PBO) and diethyl maleate (DEM) and triphenyl phosphate along with six different concentration of cypermethrin on the activities of acetylcholinesterase (AChE), esterase (EST), glutathione S-transferase (GST), and mixed-function oxidase (MFO) of A. albistriga. Results: Bioassay shows elevated LC50 for cypermethrin (63.32 ppm) whereas in a combination of PBO cypermethrin LC50 values were reduced into 12.039 ppm followed by TPP combination as 13.234 ppm. In vitro and in vivo inhibition analysis shows AChE inhibition by PBO P < 0.01, esterase inhibition by PBO, and TPP were less; GST inhibition by DEM was observed at P < 0.001. Native PAGE results revealed that the in vitro AChE isoenzyme inhibition could be possible by PBO synergism with cypermethrin in A. albistriga. Conclusions: The overall results conclude that the PBO and TPP enzyme inhibitors could be fine synergist molecules when it mixed with cypermethrin insecticide to control and manage the insecticide-resistant Amsacta albistriga in the field. [ABSTRACT FROM AUTHOR]

Gray and summer bunch rot are important diseases of table grapes due to the high economic and environmental cost of their control with synthetic fungicides. The ability to produce antifungal compounds against the causal agents Botrytis, Aspergillus, Penicillium, and Rhizopus of two microorganisms isolated from table grapes and identified as Hanseniaspora osmophila and Gluconobacter cerinus was evaluated. In dual cultures, both biocontrol agents (together and separately) inhibited in vitro mycelial growth of these pathogens. To identify the compounds responsible for the inhibitory effect, extractions were carried out with organic solvents from biocontrol agents separately. Through dual cultures with pathogens and pure extracts, only the hexane extract from H. osmophila showed an inhibitory effect against Botrytis cinerea. To further identify these compounds, the direct bioautography technique was used. This technique made it possible to determine the band displaying antifungal activity at Rf = 0.05–0.2. The compounds present in this band were identified by GC-MS and compared to the NIST library. The most abundant compounds, not previously reported, corresponded to alkanes, ketones, alcohols, and terpenoids. H. osmophila and G. cerinus have the potential to control the causal agents of gray and summer bunch rot of table grapes.

The inhibition activities and mechanisms of four anthocyanins including cyanidin-3-glucoside, cyanidin-3,5-glucoside, cyanidin-3-rutinoside, and peonidin-3-glucoside, against porcine pancreatic α-amylase were investigated through in vitro and in silico studies. The in vitro inhibition study demonstrated that the four anthocyanins competitively inhibited porcine pancreatic α-amylase, which was later verified by the in silico molecular docking study that showed all the anthocyanins bound exclusively to the active site of porcine pancreatic α-amylase. Cyanidin-3-glucoside was found to have the highest inhibition activity with the Ki value of 0.014 mM, followed by cyanidin-3-rutinoside, cyanidin-3,5-glucoside, and peonidin-3-glucoside with the Ki value of 0.019, 0.020, and 0.045 mM, respectively. Results obtained from the in silico study also showed that the four anthocyanins were surrounded by the side chains of the active site of porcine pancreatic α-amylase, among which the side chain of GLU233 was supposed to play a key role in imparting the inhibition activity of anthocyanins.

The worldwide spread of beta-lactamases with hydrolytic activity extended to last resort carbapenems is aggravating the antibiotic resistance problem and endangers the successful antimicrobial treatment of clinically relevant pathogens. As recently highlighted by the World Health Organization, new strategies to contain antimicrobial resistance are urgently needed. Class A carbapenemases include members of the KPC, GES and SFC families. These enzymes have the ability to hydrolyse penicillins, cephalosporins and carbapenems, while also being less susceptible to available beta-lactam inhibitors, such as clavulanic acid. The KPC family is the most prevalent. It is mostly found on plasmids in Klebsiella pneumoniae, meaning that great amounts of attention, in terms of inhibitor design and structural biology, have been dedicated to it, whereas no efforts have yet been dedicated to GES-type enzymes, despite their ability to rapidly and horizontally disseminate. We herein report the first in silico screening against GES-5, which is the most dangerous GES-type beta-lactamase, using a library of 800K commercially available candidates that all share drug-like properties, such as their MW, logP, rotatable bonds and HBA/HBD atoms. The best screening results were filtered to enrich the number of different chemotypes, and then submitted to molecular docking. The 34 most promising candidates were selected for in vitro validation in biochemical assays against recombinant GES-5. Six hits acted as inhibitors, in the high micromolar range, towards GES-5 and led to the identification of the first, novel chemotypes with inhibitory activity against this clinically relevant carbapenemase. [ABSTRACT FROM AUTHOR]

Based on the presence of carbamate moiety, twenty salicylanilide N -monosubstituted carbamates concomitantly with their parent salicylanilides and five newly prepared 4-chlorophenyl carbamates obtained from isocyanates were investigated using Ellman’s method for their in vitro inhibitory activity against acetylcholinesterase (AChE) from electric eel and butyrylcholinesterase (BChE) from equine serum. The carbamates and salicylanilides exhibited mostly a moderate inhibition of both cholinesterase enzymes with IC 50 values ranging from 5 to 235 µM. IC 50 values for AChE were in a narrower concentration range when compared to BChE, but many of the compounds produced a balanced inhibition of both cholinesterases. The derivatives were comparable or superior to rivastigmine for AChE inhibition, but only a few of carbamates also for BChE. Several structure-activity relationships were identified, e.g., N -phenethylcarbamates produce clearly favourable BChE inhibition. The compounds also share convenient physicochemical properties for CNS penetration. [ABSTRACT FROM AUTHOR]

The development of novel inhibitors of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) represents a viable approach to alleviate Alzheimer’s disease. Thirty-six halogenated 2-hydroxy-N-phenylbenzamides (salicylanilides) with various substitution patterns and their esters with phosphorus-based acids were synthesized in yields of 72% to 92% and characterized. They were evaluated for in vitro inhibition of AChE from electric eel and BuChE from equine serum using modified Ellman’s spectrophotometric method. The benzamides exhibited a moderate inhibition of AChE with IC50 values in a narrow concentration range from 33.1 to 85.8 µM. IC50 values for BuChE were higher (53.5−228.4 µM). The majority of derivatives inhibit AChE more efficiently than BuChE and are comparable or superior to rivastigmine—an established cholinesterases inhibitor used in the treatment of Alzheimer’s disease. Phosphorus-based esters especially improved the activity against BuChE with 5-chloro-2-{[4-(trifluoromethyl)phenyl]carbamoyl}phenyl diethyl phosphite 5c superiority (IC50 = 2.4 µM). This derivative was also the most selective inhibitor of BuChE. It caused a mixed inhibition of both cholinesterases and acted as a pseudo-irreversible inhibitor. Several structure-activity relationships were identified, e.g., favouring esters and benzamides obtained from 5-halogenosalicylic acids and polyhalogenated anilines. Both 2-hydroxy-N-phenylbenzamides and esters share convenient physicochemical properties for blood-brain-barrier penetration and thus central nervous system delivery.

Mycobacteria cause a variety of diseases, such as tuberculosis, leprosy, and opportunistic diseases in immunocompromised people. The treatment of these diseases is problematic, necessitating the development of novel treatment strategies. Recently, β-carbonic anhydrases (β-CAs) have emerged as potential drug targets in mycobacteria. The genomes of mycobacteria encode for three β-CAs that have been cloned and characterized from Mycobacterium tuberculosis (Mtb) and the crystal structures of two of the enzymes have been determined. Different classes of inhibitor molecules against Mtb β-CAs have subsequently been designed and have been shown to inhibit these mycobacterial enzymes in vitro. The inhibition of these centrally important mycobacterial enzymes leads to reduced growth of mycobacteria, lower virulence, and impaired biofilm formation. Thus, the inhibition of β-CAs could be a novel approach for developing drugs against the severe diseases caused by pathogenic mycobacteria. In the present article, we review the data related to in vitro and in vivo inhibition studies in the field.

Protein phosphatase 5 (PP5) is a unique member of serine/threonine phosphatases which has been recognized in regulation of diverse cellular processes. A cDNA fragment encoding PP5 (EcPP5) was cloned and characterized from the cantharidin-producing blister beetle, E. chinensis. EcPP5 contains an open reading frame of 1500 bp that encodes a protein of 56.89 kDa. The deduced amino acid sequence shares 88% and 68% identities to the PP5 of Tribolium castaneum and humans, respectively. Analysis of the primary sequence shows that EcPP5 has three TPR (tetratricopeptide repeat) motifs at its N-terminal region and contains a highly conserved C-terminal catalytic domain. RT-PCR reveals that EcPP5 is expressed in all developmental stages and in different tissues. The recombinant EcPP5 (rEcPP5) was produced in Escherichia coli and purified to homogeneity. The purified protein exhibited phosphatase activity towards pNPP (p-nitrophenyl phosphate) and phosphopeptides, and its activity can be enhanced by arachidonic acid. In vitro inhibition study revealed that protein phosphatase inhibitors, okadaic acid, cantharidin, norcantharidin and endothall, inhibited its activity. Further, protein phosphatase activity of total soluble protein extract from E. chinensis adults could be impeded by these inhibitors suggesting there might be some mechanism to protect this beetle from being damaged by its self-produced cantharidin. OPEN ACCESS [ABSTRACT FROM AUTHOR]

Gray and summer bunch rot are important diseases of table grapes due to the high economic and environmental cost of their control with synthetic fungicides. The ability to produce antifungal compounds against the causal agents Botrytis, Aspergillus, Penicillium, and Rhizopus of two microorganisms isolated from table grapes and identified as Hanseniaspora osmophila and Gluconobacter cerinus was evaluated. In dual cultures, both biocontrol agents (together and separately) inhibited in vitro mycelial growth of these pathogens. To identify the compounds responsible for the inhibitory effect, extractions were carried out with organic solvents from biocontrol agents separately. Through dual cultures with pathogens and pure extracts, only the hexane extract from H. osmophila showed an inhibitory effect against Botrytis cinerea. To further identify these compounds, the direct bioautography technique was used. This technique made it possible to determine the band displaying antifungal activity at Rf = 0.05–0.2. The compounds present in this band were identified by GC-MS and compared to the NIST library. The most abundant compounds, not previously reported, corresponded to alkanes, ketones, alcohols, and terpenoids. H. osmophila and G. cerinus have the potential to control the causal agents of gray and summer bunch rot of table grapes. [ABSTRACT FROM AUTHOR]

• An in vitro protocol for mammalian systems is appropriate to marine invertebrates. • Carboxylesterase substrates adequacy differs between human and invertebrates. • The flame retardant TBBPA interferes in vitro with carboxylesterases of all groups. Carboxylesterases (CEs) are key enzymes which catalyse the hydrolysis reactions of multiple xenobiotics and endogenous ester moieties. Given their growing interest in the context of marine pollution and biomonitoring, this study focused on the in vitro sensitivity of marine invertebrate CEs to some pesticides, pharmaceuticals, personal care products and plastic additives to assess their potential interaction on this enzymatic system and its suitability as biomarkers. Three bivalves, one gastropod and two crustaceans were used and CEs were quantified following current protocols set for mammalian models. Four substrates were screened for CEs determination and to test their adequacy in the hepatic fraction measures of the selected invertebrates. Two commercial recombinant human isoforms (hCE1 and hCE2) were also included for methodological validation. Among the invertebrates, mussels were revealed as the most sensitive to xenobiotic exposures while gastropods were the least as well as with particular substrate-specific preferences. Among chemicals of environmental concern, the plastic additive tetrabromobisphenol A displayed the highest CE-inhibitory capacity in all species. Since plastic additives easily breakdown from the polymer and may accumulate and metabolise in marine biota, their interaction with the CE key metabolic/detoxification processes may have consequences in invertebrate's physiology, affect bioaccumulation and therefore trophic web transfer and, ultimately, human health as shellfish consumers. [ABSTRACT FROM AUTHOR]

• Carboxylesterases are mainly located in liver and plasma of Sparus aurata. • The same isozymes seemed to hydrolyse the three substrates studied. • Hepatic carboxylesterase could have a protective role of brain AChE. • Hepatic carboxylesterase showed its utility as biomarker of pharmaceuticals. Organophosphorus (OP) and carbamate (CB) pesticides cause inhibition of acetylcholinesterase (AChE, which is the target enzyme) and carboxylesterase (CbE). However, some studies have suggested that CbE could have a potential protective role on AChE since CbE seems to be more sensitive to the inhibition by OP and CB compounds than the target enzyme. In addition, there is a great deal of concern about the presence of pharmaceutical products in the seas, and some studies have pointed out the utility of CbE as a biomarker and scavenger of them. Thus, our main aim was to study the inhibition caused by the OPs chlorpyrifos-oxon (CP-O) and dichlorvos (DCV), and the carbamate eserine on the hepatic CbE and the brain AChE of Sparus aurata. Another goal was to determine the hepatic CbE inhibition caused by ibuprofen, fenofibrate, simvastatin, carbamazepine, and triclosan. To achieve these goals, we studied the localisation of CbE in Sparus aurata and estimated the kinetic parameters of hepatic CbE. The results of this study indicate that most CbE activity occurs in the plasma and liver. However, the kinetic parameters of hepatic CbE measured on the three substrates used appeared to be very similar. Hepatic CbE was more sensitive to DCV than brain AChE, suggesting a possible protective role of CbE on AChE. Finally, CbE was shown to be sensitive to the inhibition caused by triclosan and simvastatin, indicating its utility as a biomarker and as a scavenger of these compounds to reduce the possible adverse effects on the organisms. [ABSTRACT FROM AUTHOR]

Tetrabromobisphenol A (TBBPA), a brominated flame retardant used in synthetic polymers and electronics, is present in the aquatic environment and recent evidence suggests it can be potentially biomagnified in the marine ecosystem. However, the toxicity of TBBPA in the marine biota has not been investigated in detail. In this study we aimed to understand the role of carboxylesterases (CEs) in xenobiotic metabolism under the exposure of marine organisms to a chemical of environmental concern, TBBPA. Specifically, we tested for in vitro inhibition of CE activity in a range of marine organisms covering different ecological niches, from species from low (mussels and copepods), medium (sardines and anchovies) and high trophic levels (tuna). The results revealed that the highest inhibition of CE activity to 100 μM TBBPA was recorded in mussels (66.5% inhibition) and tunids (36.3–76.4%), whereas copepods and small pelagic fish showed comparatively lower effects (respectively, 30% and 36.5–55.6%). Our results suggest that CE-mediated detoxification and physiological processes could be compromised in TBBPA-exposed organisms and could ultimately affect humans as many of them are market species. Image 1 • TBBPA inhibits carboxylesterases in a substrate dependent manner. • Butyrate esters are more sensitive than naphthyl derived forms in mussels. • Carboxylesterase inhibition by TBBPA in marine organisms is species dependent. • High trophic level predators seem to be more sensitive to TBBPA than primary consumers. [ABSTRACT FROM AUTHOR]

The genome of Mycobacterium tuberculosis (Mtb) encodes three β-carbonic anhydrases (CAs, EC 4.2.1.1) that are crucial for the life cycle of the bacterium. The Mtbβ-CAs have been cloned and characterized, and the catalytic activities of the enzymes have been studied. The crystal structures of two of the enzymes have been resolved. In vitro inhibition studies have been conducted using different classes of carbonic anhydrase inhibitors (CAIs). In vivo inhibition studies of pathogenic bacteria containing β-CAs showed that β-CA inhibitors effectively inhibited the growth of pathogenic bacteria. The in vitro and in vivo studies clearly demonstrated that β-CAs of not only mycobacterial species, but also other pathogenic bacteria, can be targeted for developing novel antimycobacterial agents for treating tuberculosis and other microbial infections that are resistant to existing drugs. In this review, we present the molecular and structural data on three β-CAs of Mtb that will give us better insights into the roles of these enzymes in pathogenic bacterial species. We also present data from both in vitro inhibition studies using different classes of chemical compounds and in vivo inhibition studies focusing on M. marinum, a model organism and close relative of Mtb. [ABSTRACT FROM AUTHOR]

Mycobacteria cause a variety of diseases, such as tuberculosis, leprosy, and opportunistic diseases in immunocompromised people. The treatment of these diseases is problematic, necessitating the development of novel treatment strategies. Recently, β-carbonic anhydrases (β-CAs) have emerged as potential drug targets in mycobacteria. The genomes of mycobacteria encode for three β-CAs that have been cloned and characterized from Mycobacterium tuberculosis (Mtb) and the crystal structures of two of the enzymes have been determined. Different classes of inhibitor molecules against Mtb β-CAs have subsequently been designed and have been shown to inhibit these mycobacterial enzymes in vitro. The inhibition of these centrally important mycobacterial enzymes leads to reduced growth of mycobacteria, lower virulence, and impaired biofilm formation. Thus, the inhibition of β-CAs could be a novel approach for developing drugs against the severe diseases caused by pathogenic mycobacteria. In the present article, we review the data related to in vitro and in vivo inhibition studies in the field. [ABSTRACT FROM AUTHOR]

Presents the abstract of the study "Effect of Benzodiazepines on the In Vitro Metabolism of Buprenorphine in Human Liver Microsomes," by David E. Moody and Yan Chang.

Dengue viruses, mosquito-borne members of the Flaviviridae family, are the causative agents of dengue fever and its associated complications, dengue haemorrhagic fever and dengue shock syndrome. To date, more than 2.5 billion people in over 100 countries are at risk of infection, and approximately 20 million infections were reported annually. There is currently no treatment or vaccine available for dengue infection. This study employed a whole-cell organism model or in vitro methods to study the inhibitory property of the flavanoid-derived compounds against DENV2 activity. Results showed that at concentration not exceeding the maximum non-toxic dose (MNTD), these compounds completely prevented DENV2 infection in HepG2 cells as indicated by the absence of cytophatic effects. The in vitro antiviral activity assessed in HepG2 cells employing virus inhibition assay showed high inhibitory activity in a dose dependent manner. At concentration below MNTD, compounds exhibited inhibitory activity against DENV2 with a range of potency strengths of 72% to 100%. The plaque forming unit per ml (pfu/ml) was reduced prominently with a maximum reduction of 98% when the infected HepG2 cells were treated with the highest non-toxic dose of compounds. The highly potent activity of the compounds against DENV2 infection strongly suggests their potential as a lead antiviral agent for dengue.

A novel, biocompatible fungicide, CD-2346, was evaluated for management of defoliation associated with greasy spot (Mycosphaerella citri Whiteside) in orange (Citrus sinensis (L.) Osbeck) and grapefruit (Citrus × paradisi Macfad.). This product contains potassium bicarbonate, potassium carbonate, urea, and a surfactant. CD-2346 (7.0 kg/ha) and a half-rate combination of CD-2346 + benomyl (0.55 kg/ha) were compared with a higher rate of benomyl (1.1 kg/ha) and commercial standards of oil (petroleum distillate FC-435-66 [70 to 93.5 liters/ha]) or oil (46.8 liters/ha) + copper sulfate (2.2 to 2.8 kg/ha). Fungicide efficacy was assessed using the area under the defoliation progress curve (AUDPC) and final defoliation in entire trees or final greasy spot severity in individual leaves. All fungicide treatments reduced the AUDPC, and all but benomyl reduced either final defoliation percentage or disease severity in individual leaves. CD-2346 and the reduced-rate combination of CD-2346 + benomyl were generally equal or superior to the full rate of benomyl in decreasing the AUDPC; CD-2346 + benomyl was equivalent to oil in reducing the AUDPC. Oil and CD-2346 treatments similarly reduced final defoliation, but oil + copper sulfate was superior to CD-2346 in reducing the AUDPC and final greasy spot defoliation or severity.