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1.
J Enzyme Inhib Med Chem ; 35(1): 1060-1068, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32314608

ABSTRACT

The carbonic anhydrases (CAs, EC 4.2.1.1) catalyse a simple but physiologically crucial reversible reaction, the carbon dioxide hydration with the production of bicarbonate and protons. In the last years, and especially, to the rapid emergence of the bacterial antibiotic resistance that is occurring worldwide, the understanding of the function of bacterial CAs has increased significantly. Recently, a new CA-class (ι-CA) was discovered in the marine diatom T. pseudonana. It has been reported that bacterial genomes may contain genes with relevant homology to the diatom ι-class CA. Still, the catalytic activity of the enzyme encoded by the gene was not investigated. Thus, herein, for the first time, we cloned, expressed, and purified the recombinant bacterial ι-CA (acronym BteCAι) identified in the genome of Burkholderia territorii. The recombinant BteCAι resulted in a good catalyst for the hydration of CO2 to bicarbonate and protons, with a kcat of 3.0 × 105 s -1 and kcat/KM of 3.9 × 107 M -1 s -1, and is also sensitive to inhibition by the sulphonamide acetazolamide. Furthermore, with the aid of the protonography, it has been demonstrated that BteCAι can be present as a dimer. This result is corroborated by the construction of a molecular model of BteCAι, which showed that the enzyme is formed by two equivalent monomers having a structure similar to a butterfly.


Subject(s)
Acetazolamide/pharmacology , Burkholderia/enzymology , Carbonic Anhydrase Inhibitors/pharmacology , Carbonic Anhydrases/metabolism , Sulfonamides/pharmacology , Acetazolamide/chemistry , Amino Acid Sequence , Carbonic Anhydrase Inhibitors/chemistry , Carbonic Anhydrases/genetics , Carbonic Anhydrases/isolation & purification , Dose-Response Relationship, Drug , Models, Molecular , Molecular Structure , Phylogeny , Recombinant Proteins/genetics , Recombinant Proteins/isolation & purification , Recombinant Proteins/metabolism , Structure-Activity Relationship , Sulfonamides/chemistry
2.
J Enzyme Inhib Med Chem ; 35(1): 824-830, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32216477

ABSTRACT

The ß-carbonic anhydrase (CA, EC 4.2.1.1) from the genome of the opportunistic pathogen Malassezia restricta (MreCA), which was recently cloned and characterised, herein has been investigated for enzymatic activation by a panel of amines and amino acids. Of the 24 compounds tested in this study, the most effective MreCA activators were L-adrenaline (KA of 15 nM), 2-aminoethyl-piperazine/morpholine (KAs of 0.25-0.33 µM), histamine, L-4-amino-phenylalanine, D-Phe, L-/D-DOPA, and L-/D-Trp (KAs of 0.32 - 0.90 µM). The least effective activators were L-/D-Tyr, L-Asp, L-/D-Glu, and L-His, with activation constants ranging between 4.04 and 12.8 µM. As MreCA is involved in dandruff and seborrhoeic dermatitis, these results are of interest to identify modulators of the activity of enzymes involved in the metabolic processes of such fungi.


Subject(s)
Amines/metabolism , Amino Acids/metabolism , Carbonic Anhydrases/metabolism , Malassezia/enzymology , Amines/chemistry , Amino Acids/chemistry , Carbonic Anhydrases/genetics , Carbonic Anhydrases/isolation & purification , Molecular Structure
3.
Molecules ; 25(5)2020 Feb 25.
Article in English | MEDLINE | ID: mdl-32106611

ABSTRACT

A new ß-class carbonic anhydrase was cloned and purified from the filamentous ascomycete Sordaria macrospora, CAS3. This enzyme has a higher catalytic activity compared to the other two such enzymes from this fungus, CAS1 and CAS2, which were reported earlier, with the following kinetic parameters: kcat of (7.9 ± 0.2) × 105 s-1, and kcat/Km of (9.5 ± 0.12) × 107 M-1∙s-1. An inhibition study with a panel of sulfonamides and one sulfamate was also performed. The most effective CAS3 inhibitors were benzolamide, brinzolamide, dichlorophnamide, methazolamide, acetazolamide, ethoxzolamide, sulfanilamide, methanilamide, and benzene-1,3-disulfonamide, with KIs in the range of 54-95 nM. CAS3 generally shows a higher affinity for this class of inhibitors compared to CAS1 and CAS2. As S. macrospora is a model organism for the study of fruiting body development in fungi, these data may be useful for developing antifungal compounds based on CA inhibition.


Subject(s)
Carbonic Anhydrase Inhibitors/chemistry , Carbonic Anhydrases/chemistry , Sordariales/enzymology , Structure-Activity Relationship , Acetazolamide/chemistry , Amino Acid Sequence/genetics , Benzolamide/chemistry , Carbonic Anhydrase Inhibitors/classification , Carbonic Anhydrase Inhibitors/pharmacology , Carbonic Anhydrases/genetics , Carbonic Anhydrases/isolation & purification , Ethoxzolamide/chemistry , Humans , Kinetics , Methazolamide/chemistry , Sulfanilamide/chemistry , Sulfonamides/chemistry , Thiazines/chemistry
4.
Anal Chem ; 91(17): 11085-11091, 2019 09 03.
Article in English | MEDLINE | ID: mdl-31366196

ABSTRACT

A proof-of-concept study is presented on the use of comprehensive two-dimensional liquid chromatography mass spectrometry (LC × LC-MS) for the separation of intact protein mixtures using a different mobile phase pH in each dimension. This system utilizes mass spectrometry (MS) friendly pH modifiers for the online coupling of high pH reversed phase liquid chromatography (HPH-RPLC) in the first dimension (1D) followed by low pH reversed phase liquid chromatography (LPH-RPLC) in the second dimension (2D). Owing to the ionic nature of proteins, the use of a different mobile phase pH was successful to provide altered selectivity between the two dimensions, even for closely related protein variants, such as bovine cytochrome c and equine cytochrome c, which differ by only three amino acids. Subminute gradient separation of proteins in the second dimension was successful to minimize analysis time, while maintaining high peak capacity. Unlike peptides, the elution order of studied proteins did not follow their isoelectric points, where acidic proteins would be expected to be more retained at low pH (and basic proteins at high pH). The steep elution isotherms (on-off retention mechanism) of proteins and the very steep gradients utilized in the second-dimension column succeeded in overcoming pH and organic solvent content mismatch. The utility of the system was demonstrated with a mixture of protein standards and an Escherichia coli protein mixture.


Subject(s)
Chromatography, Reverse-Phase/methods , Complex Mixtures/chemistry , Escherichia coli Proteins/isolation & purification , Mass Spectrometry/methods , Proteomics/methods , Animals , Carbonic Anhydrases/isolation & purification , Caseins/isolation & purification , Cattle , Cytochromes c/isolation & purification , Escherichia coli/chemistry , Horses , Hydrogen-Ion Concentration , Isoelectric Point , Lactalbumin/isolation & purification , Lactoglobulins/isolation & purification , Myoglobin/isolation & purification , Proof of Concept Study , Proteomics/instrumentation
5.
Article in English | MEDLINE | ID: mdl-31422160

ABSTRACT

In this paper, the total carbonic anhydrase (CA) enzyme was purified from horse mackerel (Trachurus trachurus) muscle with a specific activity of 23,063.93 EU/mg, purification fold of 551.08, total activity of 1522.22 EU/mL and a yield of 18.50% using sulfanilamide affinity column chromatography. For obtaining the subunit molecular mass and enzyme purity, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) for this part was performed and a single band was clearly recorded. The molecular mass of this enzyme was found approximately 35 kDa. The optimum temperature and pH values were obtained from Arrhenius plot. In addition, the inhibitory effects of different heavy metal ions (Fe2+, Cu2+, Co2+, Pb2+ Hg2+ and As3+) and some pesticides (thiram, clofentezine, propineb, deltamethrin, azoxystrobin and thiophanate) on horse mackerel (Trachurus trachurus) muscle tissue CA enzyme activities were investigated by utilizing esterase assay activity. The used metal ions and pesticides had IC50 values in the range of 0.21-13.84 mM and 3.78-70.58 mM, respectively.


Subject(s)
Carbonic Anhydrases/chemistry , Carbonic Anhydrases/isolation & purification , Perciformes/metabolism , Animals , Carbonic Anhydrase Inhibitors/chemistry , Kinetics , Metals, Heavy/chemistry , Muscles/enzymology , Pesticides/chemistry
6.
Bioorg Med Chem ; 27(17): 3889-3901, 2019 09 01.
Article in English | MEDLINE | ID: mdl-31345748

ABSTRACT

In the current work, we report the discovery of new sulfonate and sulfamate derivatives of benzofuran- and benzothiophene as potent inhibitors of human carbonic anhydrases (hCAs) II, IX and XII. A set of derivatives, 1a-t, having different substituents on the fused benzofuran and benzothiophene rings (R = alkyl, cyclohexyl, aryl, NH2, NHMe, or NMe2) was designed and synthesized. Most of the derivatives exhibited higher potency than acetazolamide as inhibitors of the purified hCAII, IX and XII isoforms. The most potent inhibitors for hCAII, hCAIX and hCAXII were 1g, 1b and 1d with an IC50 ±â€¯SEM values of 0.14 ±â€¯0.03, 0.13 ±â€¯0.03 and 0.17 ±â€¯0.06 µM, respectively. In addition, compounds 1d and 1n exerted preferential inhibitory effect against hCAXII isozyme with good potencies. Some selected compounds were docked within the active pocket of these isozymes and binding of the molecules revealed that sulfonate and sulfamate rings were located towards the active cavity and compounds coordinated to zinc ions.


Subject(s)
Benzofurans/pharmacology , Carbonic Anhydrase Inhibitors/pharmacology , Carbonic Anhydrases/metabolism , Sulfonic Acids/pharmacology , Thiophenes/pharmacology , Benzofurans/chemical synthesis , Benzofurans/chemistry , Carbonic Anhydrase Inhibitors/chemical synthesis , Carbonic Anhydrase Inhibitors/chemistry , Carbonic Anhydrases/isolation & purification , Dose-Response Relationship, Drug , HEK293 Cells , Humans , Isoenzymes/antagonists & inhibitors , Isoenzymes/isolation & purification , Isoenzymes/metabolism , Molecular Docking Simulation , Molecular Structure , Structure-Activity Relationship , Sulfonic Acids/chemical synthesis , Sulfonic Acids/chemistry , Thiophenes/chemical synthesis , Thiophenes/chemistry
7.
Prep Biochem Biotechnol ; 49(9): 891-899, 2019.
Article in English | MEDLINE | ID: mdl-31244362

ABSTRACT

The novel technology of biological carbon sequestration using microbial enzymes have numerous advantages over conventional sequestration strategies. In the present study, extracellular carbonic anhydrase (CA) producing bacteria were isolated from water samples in the Arabian Sea, India. A potential isolate, Bacillus safensis isolate AS-75 was identified based on 16S rDNA sequence analysis. The culture conditions suitable for CA production were 32 °C incubation temperature with 4% NaCl and 10 mM Zn supplementation. Experimental optimization of culture conditions enhanced enzyme activity to 265 U mL-1. CA specific gene was characterized and based on the analysis, the CA of B. safensis isolate AS-75 was a leucine (11.3%) with α-helices as the dominant component in its secondary structure. Based on soil microcosm studies, CA could sequester CO2 by 95.4% ± 0.11% in sterilized soil with enzyme microcosm. Hence, the application of enzyme was found to be more effective in removing CO2.


Subject(s)
Bacillus/enzymology , Carbon Dioxide/metabolism , Carbonic Anhydrases/metabolism , Seawater/microbiology , Amino Acid Sequence , Bacillus/chemistry , Bacillus/metabolism , Carbonic Anhydrases/chemistry , Carbonic Anhydrases/isolation & purification , Enzymes, Immobilized/chemistry , Enzymes, Immobilized/metabolism , Kinetics , Models, Molecular , Soil Microbiology , Temperature
8.
Int J Mol Sci ; 20(10)2019 May 17.
Article in English | MEDLINE | ID: mdl-31108925

ABSTRACT

The cloning, purification, and initial characterization of the ß-carbonic anhydrase (CA, EC 4.2.1.1) from the genome of the opportunistic pathogen Malassezia restricta (MreCA), which a fungus involved in dandruff and seborrheic dermatitis (SD), is reported. MreCA is a protein consisting of 230 amino acid residues and shows high catalytic activity for the hydration of CO2 into bicarbonate and protons, with the following kinetic parameters: kcat of 1.06 × 106 s-1 and kcat/KM of 1.07 × 108 M-1 s-1. It is also sensitive to inhibition by the sulfonamide acetazolamide (KI of 50.7 nM). Phylogenetically, MreCA and other CAs from various Malassezia species seem to be on a different branch, distinct from that of other ß-CAs found in fungi, such as Candida spp., Saccharomyces cerevisiae, Aspergillus fumigatus, and Sordaria macrospora, with only Cryptococcus neoformans and Ustilago maydis enzymes clustering near MreCA. The further characterization of this enzyme and the identification of inhibitors that may interfere with its life cycle might constitute new strategies for fighting dandruff and SD.


Subject(s)
Dandruff/microbiology , Dermatitis, Seborrheic/microbiology , Fungal Proteins/isolation & purification , Malassezia/enzymology , Carbon Dioxide/metabolism , Carbonic Anhydrase Inhibitors/pharmacology , Carbonic Anhydrases/genetics , Carbonic Anhydrases/isolation & purification , Cloning, Molecular , Fungal Proteins/genetics , Humans , Phylogeny , Sulfonamides/pharmacology
9.
Article in English | MEDLINE | ID: mdl-31129291

ABSTRACT

Mollusk biomineralization is a process controlled by a complex interplay of proteins, ions and external regulators. In spite of several studies, there is a lack of knowledge of who (molecules involved), how (mechanism) and why (evolution and adaptation) mollusk are designed as we know them. In this study, a shell matrix protein, N66, has been purified and characterized biochemically from the shell of Pteria sterna. Two protein bands with carbohydrates associated were separated with a molecular weight of ~60 and 64 kDa. It has carbonic anhydrase activity and it is able to form crystal polymorphs of calcium carbonate in vitro. The mRNA N66 was obtained from the mantle tissue of Pteria sterna and the deduced amino acid sequence contained a carbonic anhydrase (CA) domain and a Asn/Gly-rich domain (aa243-439). The CA domain contained three His residues acting as zinc ligands and the gate-keeper residues present in all α-CAs (Glu166-Thr525), being thus similar to the human isoform hCAVII. Also, to test whether the posttranslational modifications present on the native N66 affects the CA activity and its crystallization capability in vitro, a recombinant N66 was overexpressed in Escherichia coli and functionally characterized. Our results show that recombinant N66 has higher CA activity and produce larger size crystals in vitro than the native N66 protein, suggesting that intrinsic properties of the native N66, such as glycosylations and/or phosphorylations, might regulate its activity.


Subject(s)
Animal Shells/metabolism , Carbonic Anhydrases/isolation & purification , Carbonic Anhydrases/metabolism , Pinctada/metabolism , Amino Acid Sequence , Animals , Base Sequence , Biomineralization , Carbonic Anhydrases/genetics , Crystallization , DNA, Complementary/genetics , Microscopy, Electron, Scanning , Phylogeny , Pinctada/genetics , Recombinant Proteins/genetics , Recombinant Proteins/metabolism , Sequence Homology, Amino Acid
10.
Bioorg Chem ; 89: 103004, 2019 08.
Article in English | MEDLINE | ID: mdl-31129502

ABSTRACT

The synthesis, characterization and biological evaluation of a series of novel N-substituted phthalazine sulfonamide (5a-l) are disclosed. Phthalazines which are nitrogen-containing heterocyclic compounds are biologically preferential scaffolds, endowed with versatile pharmacological activity, such as anti-inflammatory, cardiotonic vasorelaxant, anticonvulsant, antihypertensive, antibacterial, anti-cancer action. The compounds were investigated for the inhibition against the cytosolic hCA I, II and AChE. Most screened sulfonamides showed high potency in inhibiting hCA II, widely involved in glaucoma, epilepsy, edema, and other pathologies (Kis in the ranging from 6.32 ±â€¯0.06 to 128.93 ±â€¯23.11 nM). hCA I was inhibited with Kis in the range of 6.80 ±â€¯0.10-85.91 ±â€¯7.57 nM, whereas AChE in the range of 60.79 ±â€¯3.51-249.55 ±â€¯7.89 nM. ADME prediction study of the designed N-substituted phthalazine sulfonamides showed that they are not only with carbonic anhydrase and acetylcholinesterase inhibitory activities but also with appropriate pharmacokinetic, physicochemical parameters and drug-likeness properties. Also, in silico docking studies were investigated the binding modes of selected compounds, to hCA I, II, and AChE.


Subject(s)
Carbonic Anhydrase Inhibitors/pharmacology , Cholinesterase Inhibitors/pharmacology , Molecular Docking Simulation , Phthalazines/pharmacology , Sulfonamides/pharmacology , Acetylcholinesterase/metabolism , Animals , Carbonic Anhydrase Inhibitors/chemical synthesis , Carbonic Anhydrase Inhibitors/chemistry , Carbonic Anhydrases/isolation & purification , Carbonic Anhydrases/metabolism , Cholinesterase Inhibitors/chemical synthesis , Cholinesterase Inhibitors/chemistry , Dose-Response Relationship, Drug , Electrophorus , Humans , Isoenzymes/antagonists & inhibitors , Isoenzymes/metabolism , Molecular Structure , Phthalazines/chemical synthesis , Phthalazines/chemistry , Structure-Activity Relationship , Sulfonamides/chemical synthesis , Sulfonamides/chemistry
11.
Int J Mol Sci ; 20(6)2019 Mar 25.
Article in English | MEDLINE | ID: mdl-30934614

ABSTRACT

Carbonic anhydrases (CAs) represent a group of enzymes that catalyse important reactions of carbon dioxide hydration and dehydration, a reaction crucial to many biological processes and environmental biotechnology. In this study we successfully constructed a thermostable fusion enzyme composed of the Sulfurihydrogenibium azorense carbonic anhydrase (Saz_CA), the fastest CA discovered to date, and the chitin binding domain (ChBD) of chitinase from Bacillus circulans. Introduction of ChBD to the Saz_CA had no major impact on the effect of ions or inhibitors on the enzymatic activity. The fusion protein exhibited no negative effects up to 60 °C, whilst the fusion partner appears to protect the enzyme from negative effects of magnesium. The prepared biocatalyst appears to be thermally activated at 60 °C and could be partially purified with heat treatment. Immobilisation attempts on different kinds of chitin-based support results have shown that the fusion enzyme preferentially binds to a cheap, untreated chitin with a large crystallinity index over more processed forms of chitin. It suggests significant potential economic benefits for large-scale deployment of immobilised CA technologies such as CO2 utilisation or mineralisation.


Subject(s)
Bacteria/enzymology , Carbon Dioxide/metabolism , Carbonic Anhydrases/metabolism , Chitin/metabolism , Immobilized Proteins/metabolism , Recombinant Fusion Proteins/chemistry , Temperature , Water/metabolism , Carbonic Anhydrase Inhibitors/pharmacology , Carbonic Anhydrases/isolation & purification , Crystallization , Enzyme Stability , Ions , Molecular Weight , Protein Domains , Recombinant Fusion Proteins/metabolism
12.
Mar Drugs ; 17(3)2019 Mar 01.
Article in English | MEDLINE | ID: mdl-30832211

ABSTRACT

The ubiquitous metalloenzymes carbonic anhydrases (CAs, EC 4.2.1.1) are responsible for the reversible hydration of CO2 to bicarbonate (HCO3-) and protons (H⁺). Bicarbonate may subsequently generate carbonate used in many functional activities by marine organisms. CAs play a crucial role in several physiological processes, e.g., respiration, inorganic carbon transport, intra and extra-cellular pH regulation, and bio-mineralization. Multiple transcript variants and protein isoforms exist in the organisms. Recently, 16 α-CA isoforms have been identified in the coral Stylophora pistillata. Here, we focalized the interest on three coral isoforms: SpiCA1 and SpiCA2, localized in the coral-calcifying cells; and SpiCA3, expressed in the cytoplasm of the coral cell layers. The three recombinant enzymes were heterologously expressed and investigated for their inhibition profiles with sulfonamides and sulfamates. The three coral CA isoforms differ significantly in their susceptibility to inhibition with sulfonamides. This study provides new insights into the coral physiology and the comprehension of molecular mechanisms involved in the bio-mineralization processes, since CAs interact with bicarbonate transporters, accelerating the trans-membrane bicarbonate movement and modulating the pH at both sides of the plasma membranes.


Subject(s)
Anthozoa/metabolism , Carbonic Anhydrase Inhibitors/pharmacology , Carbonic Anhydrases/metabolism , Sulfonamides/pharmacology , Amino Acid Sequence , Animals , Anthozoa/drug effects , Anthozoa/genetics , Carbonic Anhydrases/genetics , Carbonic Anhydrases/isolation & purification , Genome , Isoenzymes/antagonists & inhibitors , Isoenzymes/genetics , Isoenzymes/isolation & purification , Isoenzymes/metabolism , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Recombinant Proteins/isolation & purification , Recombinant Proteins/metabolism , Structure-Activity Relationship
13.
Biochimie ; 160: 200-209, 2019 May.
Article in English | MEDLINE | ID: mdl-30898645

ABSTRACT

Here, for the first time, we report the presence of highly active extracellular carbonic anhydrase (CA) of α-class in cyanobacterial cells. The enzyme activity was confirmed both in vivo in intact cells and in vitro, using the recombinant protein. CA activity in intact cells of Cyanothece sp. ATCC 51142 reached ∼0.6 Wilbur-Anderson units (WAU) per 1 mg of total cell protein, and it was inhibited by a specific CAs inhibitor, ethoxyzolamide. The genes cce_4328 (ecaA) and cce_0871 (ecaB), encoding two potential extracellular CAs of Cyanothece have been cloned, and the corresponding proteins EcaA and EcaB, representing CAs of α- and ß-class, respectively, have been heterologously expressed in Escherichia coli. High specific activity (∼1.1 × 104 WAU per 1 mg of target protein) was detected for the recombinant EcaA only. The presence of EcaA in the outer cellular layers of Cyanothece was confirmed by immunological analysis with antibodies raised against the recombinant protein. The absence of redox regulation of EcaA activity indicates that this protein does not possess a disulfide bond essential for some α-class CAs. The content and activity of EcaA in a fraction of periplasmic proteins was higher in Cyanothece cells grown at ambient concentration of CO2 (0.04%) compared to those grown at an elevated CO2 concentration (1.7%). At the same time, the level of ecaA gene mRNA varied insignificantly in response to changes in CO2 supply. Our results indicate that EcaA is responsible for CA activity of intact Cyanothece cells and point to its possible physiological role under low-CO2 conditions.


Subject(s)
Bacterial Proteins/metabolism , Carbon Dioxide/metabolism , Carbonic Anhydrases/metabolism , Cyanothece/enzymology , Extracellular Space/enzymology , Recombinant Proteins/metabolism , Bacterial Proteins/genetics , Bacterial Proteins/isolation & purification , Carbonic Anhydrases/genetics , Carbonic Anhydrases/isolation & purification , Cloning, Molecular , Recombinant Proteins/genetics , Recombinant Proteins/isolation & purification
14.
Int J Biol Macromol ; 131: 445-452, 2019 Jun 15.
Article in English | MEDLINE | ID: mdl-30876900

ABSTRACT

Bacterium Bacillus sp. SS105, isolated from Free Air CO2 Enriched (FACE) soil was previously screened for carbonic anhydrase activity and CO2 sequestration. In this study, strain was selected to amplify carbonic anhydrase encoding genes. The CA genes from Bacillus sp. SS105 were found to be homologous with beta­carbonic anhydrase (ß-CA) and gamma­carbonic anhydrase (γ-CA). Both types of CA genes was cloned in pET30b (+) and expressed in E coliBL21 (DE3) with His-tag at the N-terminus. The recombinant proteins were purified by Ni-NTA affinity chromatography. The molecular size of ß-CA and γ-CA were approximately 27 kDa and 25 kDa respectively. The optimum pH and temperature were found to be 8.0 and 37 °C respectively. The Zn+ was enhancing the CAs enzyme activity. Anions and modulators showed inhibitory effect on CAs at specific concentration. Functional domain analysis of both CA proteins showed conserved region of respective proteins. Recombinant enzymes were used for bio-mineralization based conversion of atmospheric CO2 into valuable calcite. Calcite formation was evaluated with or without use of enzymes and confirmed by SEM and XRD analysis. SEM result confirmed the conversion of flower-shaped unstable form of vaterite to hexagonal cubic stable form of calcite in presence of enzymes.


Subject(s)
Bacillus/genetics , Biomimetics , Carbon Dioxide/chemistry , Carbonic Anhydrases/chemistry , Carbonic Anhydrases/genetics , Recombinant Proteins/chemistry , Recombinant Proteins/genetics , Bacillus/classification , Bacillus/enzymology , Biomimetics/methods , Carbonic Anhydrases/isolation & purification , Chromatography, Affinity , Cloning, Molecular , Enzyme Activation , Enzyme Stability , Gene Expression , Hydrogen-Ion Concentration , Kinetics , Phylogeny , Recombinant Proteins/isolation & purification , Spectrum Analysis , Temperature
15.
J Enzyme Inhib Med Chem ; 34(1): 510-518, 2019 Dec.
Article in English | MEDLINE | ID: mdl-30688123

ABSTRACT

Carbonic anhydrases (CAs) are ubiquitous metalloenzymes, which started to be investigated in detail in pathogenic, as well as non-pathogenic species since their pivotal role is to accelerate the physiological CO2 hydration/dehydration reaction significantly. Here, we propose the marine unicellular diatom Phaeodactylum tricornutum as a model organism for testing the membrane penetrability of CA inhibitors (CAIs). Seven inhibitors belonging to the sulphonamide type and possessing a diverse scaffold have been explored for their in vitro inhibition of the whole diatom CAs and the in vivo inhibitory effect on the growth of P. tricornutum. Interesting, inhibition of growth was observed, in vivo, demonstrating that this diatom is a good model for testing the cell wall penetrability of this class of pharmacological agents. Considering that many pathogens are difficult and dangerous to grow in the laboratory, the growth inhibition of P. tricornutum with different such CAIs may be subsequently used to design inhibition studies of CAs from pathogenic organisms.


Subject(s)
Carbonic Anhydrase Inhibitors/pharmacology , Carbonic Anhydrases/metabolism , Diatoms/drug effects , Sulfonamides/pharmacology , Carbonic Anhydrase Inhibitors/chemical synthesis , Carbonic Anhydrase Inhibitors/chemistry , Carbonic Anhydrases/isolation & purification , Cell Membrane Permeability/drug effects , Diatoms/enzymology , Diatoms/growth & development , Dose-Response Relationship, Drug , Models, Molecular , Molecular Structure , Structure-Activity Relationship , Sulfonamides/chemical synthesis , Sulfonamides/chemistry
16.
Molecules ; 23(12)2018 Nov 28.
Article in English | MEDLINE | ID: mdl-30486513

ABSTRACT

We report the cloning and catalytic activity of a ß-carbonic anhydrase (CA, EC 4.2.1.1), isolated from the pathogenic protozoan Entamoeba histolytica, EhiCA. This enzyme has a high catalytic activity for the physiologic CO2 hydration reaction, with a kcat of 6.7 × 105 s-1 and a kcat/Km of 8.9 × 107 M-1 × s-1. An anion inhibition study of EhiCA with inorganic/organic anions and small molecules revealed that fluoride, chloride, cyanide, azide, pyrodiphosphate, perchlorate, tetrafluoroborate and sulfamic acid did not inhibit the enzyme activity, whereas pseudohalides (cyanate and thiocyanate), bicarbonate, nitrate, nitrite, diethyldithiocarbamate, and many complex inorganic anions showed inhibition in the millimolar range (KIs of 0.51⁻8.4 mM). The best EhiCA inhibitors were fluorosulfonate, sulfamide, phenylboronic acid and phenylarsonic acid (KIs in the range of 28⁻86 µM). Since ß-CAs are not present in vertebrates, the present study may be useful for detecting lead compounds for the design of effective enzyme inhibitors, with potential to develop anti-infectives with alternative mechanisms of action.


Subject(s)
Carbonic Anhydrases , Cloning, Molecular , Entamoeba histolytica , Protozoan Proteins , Carbonic Anhydrase Inhibitors/chemistry , Carbonic Anhydrases/chemistry , Carbonic Anhydrases/genetics , Carbonic Anhydrases/isolation & purification , Entamoeba histolytica/enzymology , Entamoeba histolytica/genetics , Protozoan Proteins/chemistry , Protozoan Proteins/genetics , Protozoan Proteins/isolation & purification
17.
Arch Pharm (Weinheim) ; 351(9): e1800167, 2018 Sep.
Article in English | MEDLINE | ID: mdl-30079554

ABSTRACT

We report the synthesis of bromoindenoquinolines (15a-f) by Friedlander reactions in low yields (13-50%) and the conversion of the corresponding phenyl-substituted indenoquinoline derivatives 16-21 in high yields (80-96%) by Suzuki coupling reactions. To explore the structure-activity relationship (SAR), their inhibition potentials to inhibit acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and human carbonic anhydrase cyctosolic (hCA I and II) enzymes were determined. Monophenyl (16-18) indenoquinolines significantly inhibited the AChE and BChE enzymes in ranges of IC50 37-57 nM and 84-93 nM, respectively, compared with their starting materials 15a-c and reference compounds (galanthamine and tacrine). On the other hand, these novel arylated indenoquinoline-based derivatives were effective inhibitors of the BChE, hCA I and II, BChE and AChE enzymes with Ki values in the range of 37 ± 2.04 to 88640 ± 1990 nM for AChE, 120.94 ± 37.06 to 1150.95 ± 304.48 nM for hCA I, 267.58 ± 98.05 to 1568.16 ± 438.67 nM for hCA II, and 84 ± 3.86 to 144120 ± 2910 nM for BChE. As a result, monophenyl indenoquinolines 16-18 may have promising anti-Alzheimer drug potential and 3,8-dibromoindenoquinoline amine (15f) can be novel hCA I and hCA II enzyme inhibitors.


Subject(s)
Acetylcholinesterase/metabolism , Butyrylcholinesterase/metabolism , Carbonic Anhydrase Inhibitors/pharmacology , Carbonic Anhydrases/metabolism , Cholinesterase Inhibitors/pharmacology , Quinolines/pharmacology , Animals , Carbonic Anhydrase Inhibitors/chemical synthesis , Carbonic Anhydrase Inhibitors/chemistry , Carbonic Anhydrases/isolation & purification , Cholinesterase Inhibitors/chemical synthesis , Cholinesterase Inhibitors/chemistry , Dose-Response Relationship, Drug , Electric Organ , Horses , Humans , Molecular Structure , Quinolines/chemical synthesis , Quinolines/chemistry , Structure-Activity Relationship
18.
J Biochem Mol Toxicol ; 32(8): e22172, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29984873

ABSTRACT

In this work, the carbonic anhydrase (CA) enzyme was purified from Kangal Akkaraman sheep in Sivas, Turkey with specific activity value of 6681.57 EU/mg and yield of 14.90% with using affinity column chromatography. For designating the subunit molecular mass and enzyme purity, sodium dodecyl sulfate polyacrylamide gel electrophoresis method was used and single band for this procedure was obtained. The molecular mass of CA enzyme was found as 28.89 kDa. In this study, the optimum temperature and optimum pH were obtained from 30 and 7.5. Vmax and Km values for p-nitrophenylacetate substrate of the CA were determined from Lineweaver-Burk graphs. Additionally, the inhibitory results of diverse heavy metal ions (Hg+ , Fe2+ , Pb2+ , Co2+ , Ag+ , and Cu2+ ) on sheep were studied. Indeed, CA enzyme activities of Kangal sheep were investigated with using esterase procedure under in vitro conditions. The heavy metal concentrations inhibiting 50% of enzyme activity (IC50 ) and Ki values were obtained.


Subject(s)
Carbonic Anhydrase Inhibitors/pharmacology , Carbonic Anhydrases/drug effects , Metals, Heavy/pharmacology , Animals , Carbonic Anhydrases/isolation & purification , Carbonic Anhydrases/metabolism , Chromatography, Affinity , Electrophoresis, Polyacrylamide Gel , Hydrogen-Ion Concentration , Inhibitory Concentration 50 , Molecular Weight , Sheep , Substrate Specificity , Temperature
19.
Anal Chem ; 90(12): 7730-7738, 2018 06 19.
Article in English | MEDLINE | ID: mdl-29782149

ABSTRACT

Cryptophane-based biosensors are promising agents for the ultrasensitive detection of biomedically relevant targets via 129Xe NMR. Dynamic light scattering revealed that cryptophanes form water-soluble aggregates tens to hundreds of nanometers in size. Acridine orange fluorescence quenching assays allowed quantitation of the aggregation state, with critical concentrations ranging from 200 nM to 600 nM, depending on the cryptophane species in solution. The addition of excess carbonic anhydrase (CA) protein target to a benzenesulfonamide-functionalized cryptophane biosensor (C8B) led to C8B disaggregation and produced the expected 1:1 C8B-CA complex. C8B showed higher affinity at 298 K for the cytoplasmic isozyme CAII than the extracellular CAXII isozyme, which is a biomarker of cancer. Using hyper-CEST NMR, we explored the role of stoichiometry in detecting these two isozymes. Under CA-saturating conditions, we observed that isozyme CAII produces a larger 129Xe NMR chemical shift change (δ = 5.9 ppm, relative to free biosensor) than CAXII (δ = 2.7 ppm), which indicates the strong potential for isozyme-specific detection. However, stoichiometry-dependent chemical shift data indicated that biosensor disaggregation contributes to the observed 129Xe NMR chemical shift change that is normally assigned to biosensor-target binding. Finally, we determined that monomeric cryptophane solutions improve hyper-CEST saturation contrast, which enables ultrasensitive detection of biosensor-protein complexes. These insights into cryptophane-solution behavior support further development of xenon biosensors, but will require reinterpretation of the data previously obtained for many water-soluble cryptophanes.


Subject(s)
Biosensing Techniques , Carbonic Anhydrases/analysis , Electrochemical Techniques , Nanostructures/chemistry , Nuclear Magnetic Resonance, Biomolecular , Polycyclic Compounds/chemistry , Biosensing Techniques/instrumentation , Carbonic Anhydrases/isolation & purification , Carbonic Anhydrases/metabolism , Electrochemical Techniques/instrumentation , Fluorescence , Humans , Solubility , Xenon Isotopes
20.
Arch Pharm (Weinheim) ; 351(2)2018 Feb.
Article in English | MEDLINE | ID: mdl-29323749

ABSTRACT

A series of novel phloroglucinol derivatives were designed, synthesized, characterized spectroscopically and tested for their inhibitory activity against selected metabolic enzymes, including α-glycosidase, acetylcholinesterase (AChE), butyrylcholinesterase (BChE), and human carbonic anhydrase I and II (hCA I and II). These compounds displayed nanomolar inhibition levels and showed Ki values of 1.14-3.92 nM against AChE, 0.24-1.64 nM against BChE, 6.73-51.10 nM against α-glycosidase, 1.80-5.10 nM against hCA I, and 1.14-5.45 nM against hCA II.


Subject(s)
Acetylcholinesterase/metabolism , Butyrylcholinesterase/metabolism , Carbonic Anhydrases/metabolism , Enzyme Inhibitors/pharmacology , Glycoside Hydrolases/antagonists & inhibitors , Phloroglucinol/pharmacology , Animals , Carbonic Anhydrases/isolation & purification , Dose-Response Relationship, Drug , Electrophorus , Enzyme Inhibitors/chemical synthesis , Enzyme Inhibitors/chemistry , Glycoside Hydrolases/metabolism , Horses , Humans , Molecular Docking Simulation , Molecular Structure , Phloroglucinol/chemical synthesis , Phloroglucinol/chemistry , Structure-Activity Relationship
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