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1.
J Inorg Biochem ; 260: 112689, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39121601

RESUMO

In the search of new cymantrenyl- and ferrocenyl-sulfonamides as potencial inhibitors of human carbonic anhydrases (hCAs), four compounds based on N-ethyl or N-methyl benzenesulfonamide units have been obtained. These cymantrenyl (1a-b) and ferrocenyl (2a-b) derivatives were prepared by the reaction between aminobenzene sulfonamides ([NH2-(CH2)n-(C6H4)-SO2-NH2)], where n = 1, 2) with cymantrenyl sulfonyl chloride (P1) or ferrocenyl sulfonyl chloride (P2), respectively. All compounds were characterized by conventional spectroscopic techniques and cyclic voltammetry. In the solid state, the molecular structures of compounds 1a, 1b, and 2b were determined by single-crystal X-ray diffraction. Biological evaluation as carbonic anhydrases inhibitors were carried out and showed derivatives 1b y 2b present a higher inhibition than the drug control for the Human Carbonic Anhydrase (hCA) II and IX isoforms (KI = 7.3 nM and 5.8 nM, respectively) and behave as selective inhibition for hCA II isoform. Finally, the docking studies confirmed they share the same binding site and interactions as the known inhibitors acetazolamide (AAZ) and agree with biological studies.


Assuntos
Inibidores da Anidrase Carbônica , Anidrases Carbônicas , Simulação de Acoplamento Molecular , Sulfonamidas , Humanos , Inibidores da Anidrase Carbônica/química , Inibidores da Anidrase Carbônica/síntese química , Inibidores da Anidrase Carbônica/farmacologia , Sulfonamidas/química , Sulfonamidas/farmacologia , Sulfonamidas/síntese química , Anidrases Carbônicas/metabolismo , Anidrases Carbônicas/química , Anidrase Carbônica II/antagonistas & inibidores , Anidrase Carbônica II/metabolismo , Anidrase Carbônica II/química , Anidrase Carbônica IX/antagonistas & inibidores , Anidrase Carbônica IX/metabolismo , Antígenos de Neoplasias/metabolismo , Antígenos de Neoplasias/química , Anidrase Carbônica I/antagonistas & inibidores , Anidrase Carbônica I/metabolismo , Benzenossulfonamidas , Compostos Organometálicos/química , Compostos Organometálicos/síntese química , Compostos Organometálicos/farmacologia , Cristalografia por Raios X
2.
J Hazard Mater ; 476: 135005, 2024 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-38996684

RESUMO

Microbially induced carbonate precipitation (MICP) immobilizes toxic metals and reduces their bioavailability in aqueous systems. However, its application in the treatment of acid mine drainage (AMD) is poorly understood. In this study, the genomes of Sporosarcina sp. UB5 and UB10 were sequenced. Urease, carbonic anhydrases, and metal resistance genes were identified and enzymatic assays were performed for their validation. The geochemical mechanism of precipitation in AMD was elucidated through geo-mineralogical analysis. Sporosarcina sp. UB5 was shown to be a new genomospecies, with an average nucleotide identity < 95 % (ANI) and DNA-DNA hybridization < 70 % (DDH) whereas UB10 is close to S. pasteurii. UB5 contained two urease operons, whereas only one was identified in UB10. The ureolytic activities of UB5 and UB10 were 122.67 ± 15.74 and 131.70 ± 14.35 mM NH4+ min-1, respectively. Both strains feature several carbonic anhydrases of the α, ß, or γ families, which catalyzed the precipitation of CaCO3. Only Sporosarcina sp. UB5 was able to immobilize metals and neutralize AMD. Geo-mineralogical analyses revealed that UB5 directly immobilized Fe (1-23 %), Mn (0.65-1.33 %) and Zn (0.8-3 %) in AMD via MICP and indirectly through adsorption to calcite and binding to bacterial cell walls. The MICP-treated AMD exhibited high removal rates (>67 %) for Ag, Al, As, Ca, Cd, Co, Cu, Fe, Mn, Pb, and Zn, and a removal rate of 15 % for Mg. This study provides new insights into the MICP process and its applications to AMD treatment using autochthonous strains.


Assuntos
Mineração , Sporosarcina , Urease , Sporosarcina/genética , Sporosarcina/metabolismo , Urease/metabolismo , Precipitação Química , Carbonatos/química , Anidrases Carbônicas/metabolismo , Anidrases Carbônicas/genética , Poluentes Químicos da Água/metabolismo , Poluentes Químicos da Água/química
3.
PeerJ ; 12: e17429, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38827285

RESUMO

Background: Carbonic anhydrase VI (CA VI) is crucial in regulating oral pH and predicting susceptibility to dental caries. The hypothesis posits that caries activity may alter the CA VI function, diminishing its capacity to regulate pH effectively and potentially exacerbating cariogenic challenges. This 1-year cohort study sought to investigate the enzymatic activity of salivary CA VI and buffering capacity following a 20% sucrose rinse in 4 to 6.5-year-old children. Method: This research involved 46 volunteers categorized into three groups based on their caries status after follow-up: caries-free (CFee), arrested caries (CArrested), and caries active (CActive). Children underwent visible biofilm examination and saliva collection for salivary flow rate, buffering capacity, and CA VI analyses before and after a 20% sucrose rinse. Results: A reduction in the buffering capacity was observed after sucrose rinse in all groups. The CA VI activity decreased significantly in CFee and CArrested groups after sucrose rinse, although it did not change in the CActive group. An improvement in the buffering capacity and salivary flow rate was found at follow-up when compared with the baseline. After 1-year follow-up, buffering capacity and salivary flow rate increased in all groups, whilst the CA VI activity reduced only in CFree and CArrested children. Conclusion: Sucrose rinse universally reduces the salivary buffering capacity, while caries activity may disrupt CA VI activity response during a cariogenic challenge. After a year, increased salivary flow enhances buffering capacity but not CA VI activity in caries-active children.


Assuntos
Anidrases Carbônicas , Cárie Dentária , Saliva , Sacarose , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Soluções Tampão , Anidrases Carbônicas/metabolismo , Concentração de Íons de Hidrogênio , Estudos Longitudinais , Saliva/enzimologia , Saliva/química , Sacarose/farmacologia , Ativação Enzimática/efeitos dos fármacos
4.
Int J Mol Sci ; 24(11)2023 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-37298353

RESUMO

The involvement of carbonic anhydrases (CAs) in a myriad of biological events makes the development of new inhibitors of these metalloenzymes a hot topic in current Medicinal Chemistry. In particular, CA IX and XII are membrane-bound enzymes, responsible for tumour survival and chemoresistance. Herein, a bicyclic carbohydrate-based hydrophilic tail (imidazolidine-2-thione) has been appended to a CA-targeting pharmacophore (arylsulfonamide, coumarin) with the aim of studying the influence of the conformational restriction of the tail on the CA inhibition. For this purpose, the coupling of sulfonamido- or coumarin-based isothiocyanates with reducing 2-aminosugars, followed by the sequential acid-promoted intramolecular cyclization of the corresponding thiourea and dehydration reactions, afforded the corresponding bicyclic imidazoline-2-thiones in good overall yield. The effects of the carbohydrate configuration, the position of the sulfonamido motif on the aryl fragment, and the tether length and substitution pattern on the coumarin were analysed in the in vitro inhibition of human CAs. Regarding sulfonamido-based inhibitors, the best template turned out to be a d-galacto-configured carbohydrate residue, meta-substitution on the aryl moiety (9b), with Ki against CA XII within the low nM range (5.1 nM), and remarkable selectivity indexes (1531 for CA I and 181.9 for CA II); this provided an enhanced profile in terms of potency and selectivity compared to more flexible linear thioureas 1-4 and the drug acetazolamide (AAZ), used herein as a reference compound. For coumarins, the strongest activities were found for substituents devoid of steric hindrance (Me, Cl), and short linkages; derivatives 24h and 24a were found to be the most potent inhibitors against CA IX and XII, respectively (Ki = 6.8, 10.1 nM), and also endowed with outstanding selectivity (Ki > 100 µM against CA I, II, as off-target enzymes). Docking simulations were conducted on 9b and 24h to gain more insight into the key inhibitor-enzyme interactions.


Assuntos
Anidrases Carbônicas , Neoplasias , Humanos , Estrutura Molecular , Inibidores da Anidrase Carbônica/farmacologia , Inibidores da Anidrase Carbônica/química , Relação Estrutura-Atividade , Anidrase Carbônica IX/metabolismo , Anidrases Carbônicas/metabolismo , Antígenos de Neoplasias , Cumarínicos/farmacologia , Cumarínicos/química , Glicoconjugados , Carboidratos
5.
Chemosphere ; 308(Pt 3): 136569, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36155023

RESUMO

Green turtles, Chelonia mydas, have been included in biomonitoring efforts given its status as an endangered species. Many studies, however, rely on samples from stranded animals, raising the question of how death affects important biochemical and molecular biomarkers. The goal of this study was to investigate post mortem fluctuations in the antioxidant response and metabolism of carbohydrates in the liver of C. mydas. Liver samples were obtained from six green turtles which were submitted to rehabilitation and euthanized due to the impossibility of recovery. Samples were collected immediately after death (t = 0) and at various time intervals (1, 2, 3, 4, 5, 6, 12, 18 and 24 h post mortem), frozen in liquid nitrogen and stored at -80 °C. The activities of catalase (CAT), glutathione peroxidase (GPx), glutathione reductase (GR) and glucose-6-phosphate dehydrogenase (G6PDH) were analyzed, as were the levels of lipid peroxidation, glycogen concentration, RNA integrity (RNA IQ) and transcript levels of carbonic anhydrase and pyruvate carboxylase genes. Comparison between post mortem intervals showed a temporal stability for all the biomarkers evaluated, suggesting that changes in biochemical and molecular parameters following green turtle death are not immediate, and metabolism may remain somewhat unaltered up to 24 h after death. Such stability may be associated with the overall lower metabolism of turtles, especially under an oxygen deprivation scenario such as organismal death. Overall, this study supports the use of biomarkers in sea turtles sampled within a period of 24 h post mortem for biomonitoring purposes, though it is recommended that post mortem fluctuations of particular biomarkers be evaluated prior to their application, given that proteins may show varying degrees of susceptibility to proteolysis.


Assuntos
Anidrases Carbônicas , Tartarugas , Animais , Antioxidantes/metabolismo , Biomarcadores/metabolismo , Anidrases Carbônicas/metabolismo , Catalase/metabolismo , Glucosefosfato Desidrogenase/genética , Glucosefosfato Desidrogenase/metabolismo , Glutationa Peroxidase/metabolismo , Glutationa Redutase/metabolismo , Glicogênio/metabolismo , Nitrogênio/metabolismo , Oxigênio/metabolismo , Piruvato Carboxilase/metabolismo , RNA/metabolismo , Tartarugas/metabolismo
6.
J Enzyme Inhib Med Chem ; 36(1): 2118-2127, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34607524

RESUMO

New C-glycosides and α,ß-unsaturated ketones incorporating the 4-hydroxy-3-methoxyphenyl (vanillin) moiety as inhibitors of carbonic anhydrase (CA, EC 4.2.1.1) isoforms have been investigated. The inhibition profile of these compounds is presented against four human CA (hCA) isozymes, comprising hCAs I and II (cytosolic, ubiquitous enzymes) and hCAs IX and XII (tumour associated isozymes). Docking analysis of the inhibitors within the active sites of these enzymes has been performed and is discussed, showing that the observed selectivity could be explained in terms of an alternative pocket out of the CA active site where some of these compounds may bind. Several derivatives were identified as selective inhibitors of the tumour-associated hCA IX and XII. Their discovery might be a step in the strategy for finding an effective non-sulfonamide CA inhibitor useful in therapy/diagnosis of hypoxic tumours or other pathologies in which CA isoforms are involved.


Assuntos
Benzaldeídos/farmacologia , Anidrase Carbônica IX/antagonistas & inibidores , Inibidores da Anidrase Carbônica/farmacologia , Anidrases Carbônicas/metabolismo , Desenho de Fármacos , Antígenos de Neoplasias/metabolismo , Benzaldeídos/síntese química , Benzaldeídos/química , Sítios de Ligação/efeitos dos fármacos , Anidrase Carbônica IX/metabolismo , Inibidores da Anidrase Carbônica/síntese química , Inibidores da Anidrase Carbônica/química , Cristalografia por Raios X , Relação Dose-Resposta a Droga , Humanos , Simulação de Acoplamento Molecular , Estrutura Molecular , Relação Estrutura-Atividade
7.
Artigo em Inglês | MEDLINE | ID: mdl-34126254

RESUMO

Aeglids are unique freshwater decapods whose habitats are being impacted by metallic compounds, such as copper (Cu). Thus, we investigated the effects of acute Cu exposure on ionic regulation of Aegla castro. For this, male specimens in intermolt were collected from a reference stream and acclimated for 5 days in laboratory. After which, crabs were exposed to 11 µg L-1 Cu (Cu11) or only to water (CTR) for 24 h. Hemolymph samples were withdrawn for the determination of Na+, K+, Ca2+, and Mg2+ concentrations and the posterior gills removed for the analysis of Na+/K+-ATPase, Ca2+-ATPase, H+-ATPase, and carbonic anhydrase (CA) activities. Increased Ca2+ and Mg2+ hemolymph concentrations were observed in animals from Cu11, when compared with CTR group. In addition, decreased activity of CA was observed in animals exposed to Cu. In the current study, alterations in Ca2+ and Mg2+concentrations probably indicate that animals activated exoskeleton reabsorption mechanisms, characteristic of the premolt. Therefore, increased Ca2+ and Mg2+ concentrations in hemolymph may indicate that a biochemical signal associated with the molting cycle was triggered by Cu exposure. Despite the known harmful effects of Cu on osmoregulatory enzymes, here we observed decreased activity only in CA. However, decreased activity of CA could trigger both acid-base imbalance and ionic disruption, since CA provides H+ and HCO3- for intracellular pH maintenance, and underpins Na+ and Cl- for ionic regulation. Therefore, understanding how aeglids respond to metal contamination in laboratory conditions is crucial to assess their potential as an alternative biological model for aquatic ecotoxicology.


Assuntos
Braquiúros/efeitos dos fármacos , Cobre/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores , Braquiúros/fisiologia , Inibidores da Anidrase Carbônica/toxicidade , Anidrases Carbônicas/metabolismo , Brânquias/efeitos dos fármacos , Brânquias/enzimologia , Masculino , Equilíbrio Hidroeletrolítico/efeitos dos fármacos
8.
Food Chem ; 356: 129692, 2021 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-33819791

RESUMO

To increase milk production, antibiotics are administered to animals to provide weight gain and to prevent or treat diseases. The inappropriate use of these substances can lead to antibiotic resistance and allergic reactions and toxic effects to milk consumers. We describe the development of a simple, fast, portable, and low-cost microfluidic paper-based analytical device (µPAD) to quantify sulfonamides in milk using the inhibition of the colorimetric reaction between carbonic anhydrase (CA) and 4-nitrophenyl acetate. The main advantages presented by the µPAD include reproducible batch production, simple application, and precise analysis without previous treatment. The µPAD displayed good linearity (R2 ≥ 0.986) in a wide range of sulfonamides in milk (2.5 to 40.0 µmol L-1), being selective for the drugs even in a highly complex matrix. We expect that this device allows in situ monitoring of milk quality, reducing the prejudicial conditions associated with high concentrations of sulfonamides in milk.


Assuntos
Anidrases Carbônicas/química , Colorimetria/métodos , Leite/química , Papel , Sulfonamidas/química , Animais , Anidrases Carbônicas/metabolismo , Bovinos , Colorimetria/instrumentação , Concentração de Íons de Hidrogênio , Técnicas Analíticas Microfluídicas , Leite/metabolismo , Nitrofenóis/química , Nitrofenóis/metabolismo , Sulfonamidas/metabolismo
9.
Sci Rep ; 11(1): 7496, 2021 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-33820926

RESUMO

This quasi-experimental study sought to investigate if the mechanical control of biofilm (3-times-a-day) modifies the saliva's ability to buffer the oral environment after 20% sucrose rinse (SR20%) in children with early childhood caries (ECC). Here, SR20% reduced the saliva's pH in both groups and the mechanical control of biofilm had a greater effect on this parameter after SR20% in CF children. The mechanical control of biofilm evidenced a higher buffering capacity in CF children before SR20%, which was not observed after SR20%. Otherwise, the absence of mechanical control of biofilm showed that buffering capacity was comparable in the two groups before SR20%, whereas after SR20% the saliva's buffering capacity of CF children was higher than ECC children. When biofilm was mechanically controlled, carbonic anhydrase VI activity did not change after SR20% whereas the absence of mechanical control of biofilm reduced this enzyme activity after SR20%. In conclusion, the mechanical control of biofilm did not change saliva's ability to buffer the oral environment after SR20% in children with ECC. On the other hand, CF children appeared to regulate more effectively the saliva's pH than ECC children while the absence of mechanical control of biofilm mediated their pH-modifying ability after SR20%.


Assuntos
Biofilmes , Cárie Dentária/microbiologia , Saliva/microbiologia , Sacarose/efeitos adversos , Soluções Tampão , Anidrases Carbônicas/metabolismo , Criança , Feminino , Humanos , Concentração de Íons de Hidrogênio , Masculino , Saliva/enzimologia , Salivação/fisiologia , alfa-Amilases/metabolismo
10.
Mol Microbiol ; 116(1): 109-125, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-33550595

RESUMO

Diatoms are unicellular organisms containing red algal-derived plastids that probably originated as result of serial endosymbioses between an ancestral heterotrophic organism and a red alga or cryptophyta algae from which has only the chloroplast left. Diatom mitochondria are thus believed to derive from the exosymbiont. Unlike animals and fungi, diatoms seem to contain ancestral respiratory chains. In support of this, genes encoding gamma type carbonic anhydrases (CAs) whose products were shown to be intrinsic complex I subunits in plants, Euglena and Acanthamoeba were found in diatoms, a representative of Stramenopiles. In this work, we experimentally show that mitochondrial complex I in diatoms is a large complex containing gamma type CA subunits, supporting an ancestral origin. By using a bioinformatic approach, a complex I integrated CA domain with heterotrimeric subunit composition is proposed.


Assuntos
Anidrases Carbônicas/metabolismo , Diatomáceas/metabolismo , Complexo I de Transporte de Elétrons/metabolismo , Mitocôndrias/metabolismo , Sequência de Aminoácidos , Anidrases Carbônicas/genética , Cloroplastos/genética , Cloroplastos/metabolismo , Diatomáceas/genética , Complexo I de Transporte de Elétrons/genética , Evolução Molecular , Mitocôndrias/genética , Filogenia , RNA-Seq , Rodófitas/genética , Alinhamento de Sequência , Simbiose/genética
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