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1.
Int J Mol Sci ; 22(16)2021 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-34445200

RESUMO

In the present work, different hydrolases were adsorbed onto polypropylene beads to investigate their activity both in short-esters and polyesters synthesis. The software MODDE® Pro 13 (Sartorius) was used to develop a full-factorial design of experiments (DoE) to analyse the thermostability and selectivity of the immobilized enzyme towards alcohols and acids with different chain lengths in short-esters synthesis reactions. The temperature optima of Candida antarctica lipase B (CaLB), Humicola insolens cutinase (HiC), and Thermobifida cellulosilytica cutinase 1 (Thc_Cut1) were 85 °C, 70 °C, and 50 °C. CaLB and HiC preferred long-chain alcohols and acids as substrate in contrast to Thc_Cut1, which was more active on short-chain monomers. Polymerization of different esters as building blocks was carried out to confirm the applicability of the obtained model on larger macromolecules. The selectivity of both CaLB and HiC was investigated and best results were obtained for dimethyl sebacate (DMSe), leading to polyesters with a Mw of 18 kDa and 6 kDa. For the polymerization of dimethyl adipate (DMA) with BDO and ODO, higher molecular masses were obtained when using CaLB onto polypropylene beads (CaLB_PP) as compared with CaLB immobilized on macroporous acrylic resin beads (i.e., Novozym 435). Namely, for BDO the Mn were 7500 and 4300 Da and for ODO 8100 and 5000 Da for CaLB_PP and for the commercial enzymes, respectively. Thc_Cut1 led to polymers with lower molecular masses, with Mn < 1 kDa. This enzyme showed a temperature optimum of 50 °C with 63% of DMA and BDO when compared to 54% and 27%, at 70 °C and at 85 °C, respectively.


Assuntos
Ésteres/síntese química , Aromatizantes/síntese química , Poliésteres/síntese química , Biocatálise , Candida/enzimologia , Hidrolases de Éster Carboxílico/química , Enzimas Imobilizadas/química , Fungos do Gênero Humicola/enzimologia , Proteínas Fúngicas/química , Lipase/química , Polimerização , Thermobifida/enzimologia
2.
Molecules ; 26(6)2021 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-33808822

RESUMO

Strawberries, belonging to cultivar Clery (Fragaria × ananassa Duchesne ex Weston) and to a graft obtained by crossing Clery and Fragaria vesca L., were chosen for a study on their health potential, with regard to the prevention of chronic and degenerative diseases. Selected samples, coming from fresh and defrosted berries, submitted to different homogenization techniques combined with thermal and microwave treatments, had been previously analyzed in their polyphenolic content and antioxidant capacity. In the present work, these homogenates were evaluated in relation to their enzymatic inhibition activity towards acetylcholinesterase and butyrylcholinesterase, α-amylase, α-glucosidase and tyrosinase. All these enzymes, involved in the onset of diabetes, and neurodegenerative and other chronic diseases, were modulated by the tested samples. The inhibitory effect on tyrosinase and cholinesterase was the most valuable. Antifungal activity against Candida albicans, recently shown to play a crucial role in human gut diseases as well as diabetes, rheumatoid arthritis and Alzheimer's disease, was also shown in vitro and confirmed by the in vivo text on Galleria mellonella. Overall, the obtained results confirm once again the health potential of strawberries; however, the efficacy is dependent on high quality products submitted to correct processing flow charts.


Assuntos
Antifúngicos , Candida/enzimologia , Fragaria/química , Frutas/química , Proteínas Fúngicas/antagonistas & inibidores , Inibidores de Glicosídeo Hidrolases , Polifenóis , alfa-Amilases/antagonistas & inibidores , alfa-Glucosidases , Antifúngicos/química , Antifúngicos/farmacologia , Inibidores de Glicosídeo Hidrolases/química , Inibidores de Glicosídeo Hidrolases/farmacologia , Polifenóis/química , Polifenóis/farmacologia
3.
Molecules ; 26(4)2021 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-33670795

RESUMO

Adenia viridiflora Craib. is an indigenous edible plant that became an endangered species due to limited consumption of the local population with unknown reproduction and growth conditions. The plant is used as a traditional herb; however, its health applications lack scientific-based evidence. A. viridiflora Craib. plant parts (old leaves and young shoots) from four areas as Kamphaeng Phet (KP), Muang Nakhon Ratchasima (MN), Pakchong Nakhon Ratchasima (PN), and Uthai Thani (UT) origins were investigated for phenolic compositions and in vitro health properties through the inhibition of key enzymes relevant to obesity (lipase), diabetes (α-glucosidase and dipeptidyl peptidase-IV), Alzheimer's disease (cholinesterases and ß-secretase), and hypertension (angiotensin-converting enzyme). Phenolics including p-coumaric acid, sinapic acid, naringenin, and apigenin were detected in old leaves and young shoots in all plant origins. Old leaves exhibited higher total phenolic contents (TPCs) and total flavonoid contents (TFCs), leading to higher enzyme inhibitory activities than young shoots. Besides, PN and MN with higher TPCs and TFCs tended to exhibit greater enzyme inhibitory activities than others. These results will be useful to promote this plant as a healthy food with valuable medicinal capacities to support its consumption and agricultural stimulation, leading to sustainable conservation of this endangered species.


Assuntos
Doença , Passifloraceae/química , Fitoterapia , Extratos Vegetais/química , Água/química , Animais , Antioxidantes/análise , Candida/enzimologia , Cromatografia Líquida de Alta Pressão , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Flavonoides/análise , Cavalos , Humanos , Hipertensão/tratamento farmacológico , Fenóis/análise , Folhas de Planta/química , Brotos de Planta/química , Coelhos , Saccharomyces cerevisiae/enzimologia , Solventes
4.
Appl Biochem Biotechnol ; 193(8): 2420-2429, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33689122

RESUMO

2-Ethylhexyl palmitate (2-EHP) is one of the important chemical products. Normally, 2-EHP is produced through the esterification. Since 2-EHP has a high viscosity, the mass transfer is significantly influenced with the product accumulation. In this work, a rotating packed bed reactor with intensive mixing was employed to solve the problem in the mass transfer during the enzymatic reaction. Under the optimal conditions, compared with the traditional continuous stirred-tank reactor (CSTR), the RPB reactor enhanced the final yield of 2-EHP, and shortened the reaction time to 1 h. In addition, the enzyme has a longer life-time in the RPB reactor, with production yield of closing to 99% after 9 batches. The results of this research indicated that the RPB has a great potential to be applied in the enzymatic production of 2-EHP. Application of the rotating packed bed in synthesis of 2-ethylhexyl palmitate.


Assuntos
Reatores Biológicos , Candida/enzimologia , Enzimas Imobilizadas/química , Proteínas Fúngicas/química , Lipase/química , Palmitatos , Esterificação , Palmitatos/síntese química , Palmitatos/química
5.
Arch Microbiol ; 203(5): 2219-2228, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33630118

RESUMO

Candida genus comprises several species that can be found in the oral cavity and the gastrointestinal and genitourinary tracts of healthy individuals. Under certain conditions, however, they behave as opportunistic pathogens that colonize these tissues, most frequently when the immune system is compromised by a disease or under certain medical treatments. To colonize the human host, these organisms require to express cell wall proteins (CWP) that allowed them to adhere and adapt to the reactive oxygen (ROS) and nitrogen (RNS) species produced in the macrophage during the respiratory burst. The aim of this study was to determine how four Candida species respond to the oxidative stress imposed by cumene hydroperoxide (CHP). To this purpose, C. albicans, C. glabrata, C. krusei and C. parapsilosis were exposed to this oxidant which is known to generate ROS in the membrane phospholipids. Accordingly, both mock and CHP-exposed cells were used to extract and analyze CWP and also to measure catalase activity and the levels of protein carbonylation. Results indicated that all four species express different CWP to neutralize ROS. Most relevant among these proteins were the glycolytic enzymes enolase and glyceraldehyde-3-phosphate dehydrogenase, known as moonlight proteins because in addition to participate in glycolysis they play an important role in the cell response to ROS. In addition, a thiol-specific antioxidant enzyme (Tsa) was also found to counteract ROS.


Assuntos
Derivados de Benzeno/farmacologia , Candida/classificação , Candida/metabolismo , Oxidantes/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Antioxidantes/metabolismo , Candida/enzimologia , Parede Celular/metabolismo , Trato Gastrointestinal/microbiologia , Gliceraldeído-3-Fosfato Desidrogenases/metabolismo , Humanos , Macrófagos/imunologia , Boca/microbiologia , Fosfopiruvato Hidratase/metabolismo , Proteômica , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Sistema Urogenital/microbiologia
6.
Int J Biol Macromol ; 175: 79-86, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33548316

RESUMO

Metal organic frameworks (MOFs) are hybrid organic inorganic materials with unique properties such as well-defined pore structure, extremely high surface area, excellent chemical-thermal stability. MOFs-based constructs have been extensively engineered and used for applications, such as enzyme immobilization for bio-catalysis. To obtained a zeolitic imidazole framework-8 (ZIF-8) for enzyme immobilization, Candida rugosa lipase (CRL) was pretreated with calix [4]arene tetracarboxylic acid (Calix) and reacted with Zn and imidazole by co-precipitation method. The prepared biocomposite was characterized by SEM, EDX, FT-IR, and XRD. The prepared CRL@Calix-ZIF-8 with high encapsulation efficiency showed improved resistance to alkali and thermal conditions. The CRL@Calix-ZIF-8 with the biocatalytic activity was 2-folds higher than that of the CRL@ZIF-8 (without Calix). The free lipase lost its catalytic activity completely at 60 °C after 100 min, while the CRL@Calix-ZIF-8 and CRL@ZIF-8 retained about 84% and 73%. It was found that CRL@Calix-ZIF-8 and CRL@ZIF-8 still retained ~83 and 67% of catalytic activity after its 6th use, respectively. The kinetic resolution of the immobilized lipases was examined for enantioselective hydrolysis of racemic naproxen methyl ester. CRL@Calix-ZIF-8 showed enantioselectivity against the racemic naproxen methyl ester, with E = 183 and 131 compared to the CRL@ZIF-8.


Assuntos
Calixarenos/química , Ácidos Carboxílicos/química , Lipase/química , Fenóis/química , Biocatálise , Calixarenos/metabolismo , Candida/enzimologia , Catálise , Estabilidade Enzimática , Enzimas , Enzimas Imobilizadas/química , Ésteres/química , Concentração de Íons de Hidrogênio , Hidrólise , Cinética , Lipase/metabolismo , Estruturas Metalorgânicas/farmacologia , Fenóis/metabolismo , Espectroscopia de Infravermelho com Transformada de Fourier/métodos , Estereoisomerismo , Temperatura
7.
Bioorg Chem ; 107: 104583, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33421956

RESUMO

BACKGROUND: Indoles are important bioactive compounds that have been extensively studied in organic chemistry. In this work, a green and efficient process for the synthesis of Indoles from 1,3-diketones with fumaronitrile was developed. RESULTS: Under optimal conditions (1,3-diketones (0.5 mmol), fumaronitrile (1 mmol), water (2 ml), lipase (15 mg), 30 °C, 24 h), high yields and satisfactory regioselectivity of cyano-containing multi-substituted indoles could be obtained when CRL (C. rugosa lipase) was used as the catalyst. CONCLUSION: This enzymatic method demonstrates the great potential for the synthesis of indoles and extends the application of enzyme in organic synthesis.


Assuntos
Candida/enzimologia , Indóis/metabolismo , Lipase/metabolismo , Pseudomonas aeruginosa/enzimologia , Animais , Biocatálise , Indóis/química , Estrutura Molecular , Suínos
8.
Comput Biol Chem ; 90: 107407, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33191110

RESUMO

Natural products as well as their derivatives play a significant role in the discovery of new biologically active compounds in the different areas of our life especially in the field of medicine. The synthesis of compounds produced from natural products including cytisine is one approach for the wider use of natural substances in the development of new drugs. QSAR modeling was used to predict and select of biologically active cytisine-containing 1,3-oxazoles. The eleven most promising compounds were identified, synthesized and tested. The activity of the synthesized compounds was evaluated using the disc diffusion method against C. albicans M 885 (ATCC 10,231) strain and clinical fluconazole-resistant Candida krusei strain. Molecular docking of the most active compounds as potential inhibitors of the Candida spp. glutathione reductase was performed using the AutoDock Vina. The built classification models demonstrated good stability, robustness and predictive power. The eleven cytisine-containing 1,3-oxazoles were synthesized and their activity against Candida spp. was evaluated. Compounds 10, 11 as potential inhibitors of the Candida spp. glutathione reductase demonstrated the high activity against C. albicans M 885 (ATCC 10,231) strain and clinical fluconazole-resistant Candida krusei strain. The studied compounds 10, 11 present the interesting scaffold for further investigation as potential inhibitors of the Candida spp. glutathione reductase with the promising antifungal properties. The developed models are publicly available online at http://ochem.eu/article/120720 and could be used by scientists for design of new more effective drugs.


Assuntos
Alcaloides/farmacologia , Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Glutationa Redutase/antagonistas & inibidores , Simulação de Acoplamento Molecular , Oxazóis/farmacologia , Alcaloides/síntese química , Alcaloides/química , Antifúngicos/síntese química , Antifúngicos/química , Azocinas/síntese química , Azocinas/química , Azocinas/farmacologia , Candida/enzimologia , Glutationa Redutase/metabolismo , Testes de Sensibilidade Microbiana , Estrutura Molecular , Oxazóis/síntese química , Oxazóis/química , Relação Quantitativa Estrutura-Atividade , Quinolizinas/síntese química , Quinolizinas/química , Quinolizinas/farmacologia
9.
Bioorg Chem ; 107: 104534, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33339664

RESUMO

A novel strategy combining visible-light and enzyme catalysis in one pot for the synthesis of 4H-pyrimido[2,1-b] benzothiazole derivatives from alcohols is described for the first time. Fourteen 4H-pyrimido[2,1-b] benzothiazole derivatives were prepared with yields of up to 98% under mild reaction conditions by a simple operation. The photoorgano catalyst rose Bengal (rB) was employed to oxyfunctionalise alcohols to aldehydes. Compared with aldehydes, alcohols with more stable properties and lower cost, thus we used photocatalysis to oxidize alcohols into aldehydes. Next, the enzyme was used to further catalyze the reaction of Biginelli to produce the target product of 4H-pyrimidine [2,1-b] benzothiazole. Experimental results show that this method provides a more efficient and eco-friendly strategy for the synthesis of 4H-pyrimido[2,1-b] benzothiazole derivatives.


Assuntos
Benzotiazóis/química , Enzimas/metabolismo , Luz , Benzotiazóis/síntese química , Benzotiazóis/metabolismo , Biocatálise , Candida/enzimologia , Catálise , Enzimas/química , Proteínas Fúngicas/metabolismo , Humanos , Lipase/metabolismo , Oxirredução
10.
Curr Top Med Chem ; 21(6): 462-506, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33319673

RESUMO

1,2,3-Triazole, a five-membered heterocyclic nucleus, is widely recognized as a key chromophore of great value in medicinal chemistry for delivering compounds possessing innumerable biological activities, including antimicrobial, antitubercular, antidiabetic, antiviral, antitumor, antioxidants, and anti-inflammatory activities. Mainly, in the past years, diverse conjugates carrying this biologically valuable core have been reported due to their attractive fungicidal potential and potent effects on various infective targets. Hence, hybridization of 1,2,3-triazole with other antimicrobial pharmacophores appears to be a judicious strategy to develop new effective anti-fungal candidates to combat the emergence of drug-sensitive and drug-resistant infectious diseases. Thus, the current review highlights the recent advances of this promising category of 1,2,3-triazole-containing hybrids incorporating diverse varieties of bioactive heterocycles such as conozole, coumarin, imidazole, benzimidazole, pyrazole, indole, oxindole, chromene, pyrane, quinazoline, chalcone, isoflavone, carbohydrates, and amides. It underlies their inhibition behavior against a wide array of infectious fungal species during 2015-2020.


Assuntos
Inibidores de 14-alfa Desmetilase/farmacologia , Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Esterol 14-Desmetilase/metabolismo , Triazóis/farmacologia , Inibidores de 14-alfa Desmetilase/síntese química , Inibidores de 14-alfa Desmetilase/química , Antifúngicos/síntese química , Antifúngicos/química , Candida/enzimologia , Testes de Sensibilidade Microbiana , Conformação Molecular , Triazóis/síntese química , Triazóis/química
11.
Protein Pept Lett ; 28(2): 229-239, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-32640951

RESUMO

BACKGROUND: Flavin adenine dinucleotide (FAD) is a redox-active coenzyme that regulates several important enzymatic reactions during metabolism. FAD is used in the medicinal and food industries and FAD supplements have been used to treat some inheritable diseases. FAD can be biosynthesized from flavin mononucleotide (FMN) and adenosine triphosphate (ATP), catalyzed by FAD synthetase (FADS). OBJECTIVE: The aim of this study was to heterologously express the gene encoding FADS from the flavinogenic yeast Candida famata (FADSCf) for biosynthesis of FAD. METHODS: The sequence encoding FADSCf was retrieved and heterologously expressed in Escherichia coli. The structure and enzymatic properties of recombinant FADSCf were characterized. RESULTS: FADSCf (279 amino acids) was successfully expressed in E. coli BL21 (DE3), with a theoretical molecular weight of 32299.79 Da and an isoelectric point of 6.09. Secondary structural analysis showed that the number of α-helices was 2-fold higher than the number of ß-sheets, indicating that the protein was highly hydrophilic. Under fixed ATP concentration, FADSCf had a Km of 0.04737±0.03158 mM and a Vmax of 3.271±0.79 µM/min/mg. Under fixed FMN concentration, FADSCf had a Km of 0.1214±0.07464 mM and a Vmax of 2.6695±0.3715 µM/min/mg. Enzymatic reactions in vitro showed that expressed FADSCf could form 80 mM of FAD per mg of enzyme after 21 hours under the following conditions: 0.5 mM FMN, 5 mM ATP and 10 mM Mg2+. CONCLUSION: Under optimized conditions (0.5 mM FMN, 5 mM ATP and 10 mM Mg2+), the production of FAD reached 80 mM per mg of FADSCf after a 21-hour reaction. Our results indicate that purified recombinant FADSCf can be used for the biosynthesis of FAD.


Assuntos
Candida/enzimologia , Escherichia coli/metabolismo , Mononucleotídeo de Flavina/metabolismo , Flavina-Adenina Dinucleotídeo/metabolismo , Nucleotidiltransferases/metabolismo , Proteínas Recombinantes/metabolismo , Sequência de Aminoácidos , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Nucleotidiltransferases/química , Nucleotidiltransferases/genética , Filogenia , Conformação Proteica , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Homologia de Sequência
12.
Bioprocess Biosyst Eng ; 44(2): 369-378, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32997184

RESUMO

The present study aimed to analyze reaction kinetics and mechanism for the synthesis of propyl benzoate in solvent-free conditions. Lipase was immobilized on Hydroxypropyl methylcellulose (HPMC) and polyvinyl alcohol (PVA) polymer blend by entrapment method. Among different lipases immobilized on a support, Candida cylindracea (CCL) showed excellent activity. Systematic studies were done to optimize the reaction conditions. The activation energy was found to be 16.2 kcal/mol for immobilized CCL. Kinetic parameters were calculated, which depicted that propyl benzoate synthesized using immobilized CCL followed the ternary complex model in which propanol inhibits lipase activity at higher concentrations. Recyclability of the catalyst was checked up to four catalytic cycles and 40% retention of activity was observed up to the fourth cycle. Finally, the applicability of developed protocol to synthesize various alkyl benzoates was explored.


Assuntos
Proteínas de Bactérias/química , Benzoatos/síntese química , Burkholderia cepacia/enzimologia , Candida/enzimologia , Enzimas Imobilizadas/química , Proteínas Fúngicas/química , Lipase/química , Rhizopus oryzae/enzimologia , Biocatálise , Esterificação
13.
BMC Microbiol ; 20(1): 368, 2020 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-33272216

RESUMO

BACKGROUND: Surgical site infection (SSI) is a crucial dilemma of surgery. Patients with SSIs not only face difficulty in treatment but also bear extra cost with high mortality rate. Resistant strains of Candida have emerged as an important nosocomial pathogen. Proteinase and phospholipase are exo- enzymes of Candida species, have importance with respect to their contribution in diseases. This study focused on prevalence of Candida species in surgical wound, their resistance to antifungal drugs, co-relation of these resistance with virulence potential of Candida species and comparison of production level of exo-enzymes of Candida species isolated from patients with SSIs and healthy individuals to highlights their role in SSIs. RESULTS: A total of (n = 555) swab samples were investigated. (n = 450) samples were collected from patients with SSIs and (n = 105) were collected from healthy individuals. Samples were subjected for the identification of Candida species which were subsequently investigated for antifungal susceptibility, MICs and enzymatic activity of Candida species. Out of 128 strains of Candida spp. isolated from SSIs, 54(42.18%) were identified as C. albicans followed by C. glabrata 32(25%), C. parapsilosis 17(13.28%), C. krusei 13(10.16%) and C. tropicalis 12(9.38%). C. albicans isolates showed 100% susceptibility to voriconazole and amphotericin B followed by itraconazole 98% and fluconazole 89%. Out of 6 fluconazole resistant C. albicans 5(83.33%) were able to produce phospholipase while out of 48 fluconazole-susceptible strains 17(35.42%) were found to be phospholipase producer. Out of 54 C. albicans isolated from surgical wound 46(85.18%) and 49(90.74%) were found to be phospholipase and proteinase producer respectively, whereas out of 20 C. albicans isolates from healthy subjects 14(70%) produce proteinase and 12(60%) produce phospholipase. There were significant statistical differences found between the level of enzyme production by C. albicans, in relation to both sites (P = 0.014). CONCLUSION: Study revealed that prevalence of Candida species is high in SSIs. Phospholipase and proteinase activity were more pronounced in Candida Species from surgical wound in contrast to species from healthy individuals suggests these enzymes may have been responsible for the severity of infection in surgical wound patients.


Assuntos
Candida/isolamento & purificação , Farmacorresistência Fúngica , Peptídeo Hidrolases/metabolismo , Fosfolipases/metabolismo , Infecção da Ferida Cirúrgica/microbiologia , Distribuição por Idade , Antifúngicos/farmacologia , Candida/classificação , Candida/efeitos dos fármacos , Candida/enzimologia , Feminino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Fatores de Virulência/metabolismo
14.
Acta Odontol Latinoam ; 33(2): 104-111, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32920612

RESUMO

Candida dubliniensis (Cd) and Candida albicans (Ca) are the most frequently isolated yeasts in HIV+ patients. Some of the enzymes produced by these yeasts are considered virulence factors since they contribute to pathogenicity of Candida spp. The aim of the present study was to compare production of enzymes such as phospholipase (Ph), proteinase (P), and hemolysin (H) by Cd and Ca strains isolated from periodontal HIV-positive patients receiving and not receiving highly active antiretroviral therapy (HAART). Subgingival biofilm samples were obtained using paper points, and a sample of oral mucosa was taken using a swab. Phenotypic and molecular methods were used to isolate 39 strains of Candida, including 25 strains of Cd and 14 strains of Ca, obtained from 33 periodontal pocket samples and 6 oral mucosa samples collected from 15 HIV+ patients (8 receiving and 7 not receiving HAART). Malt egg-yolk agar, albumin agar and blood agar were used to evaluate pH, P and H production respectively. The strains were inoculated in duplicate and incubated at 37 ºC. Colony and halo diameters were measured. A greater proportion of Ca was observed in patients not receiving HAART, and a higher proportion of Cd was observed in those under HAART, Chi2 p< 0.001. Phospholipase production was observed in 92.9% percent of isolated Ca strains but in none of the isolated Cd strains. Proteinase production was high in Ca and Cd strains isolated from patients not receiving HAART. Hemolysin production was observed in all the studied strains, though it was significantly higher (p=0.04) in Ca and Cd strains isolated from patients not receiving HAART. To sum up, the proportion of Candida dubliniensis strains was highest in the subgingival biofilm of patients receiving HAART, and Cd strains were found to express fewer virulence factors than Ca strains.


Assuntos
Terapia Antirretroviral de Alta Atividade/métodos , Biofilmes/crescimento & desenvolvimento , Candida albicans/enzimologia , Candida albicans/isolamento & purificação , Candida/enzimologia , Candida/isolamento & purificação , Candidíase Bucal/microbiologia , Gengiva/microbiologia , Infecções por HIV/complicações , Candida/classificação , Candida/genética , Candida albicans/genética , Candidíase Bucal/complicações , Genótipo , Infecções por HIV/microbiologia , Humanos , Mucosa Bucal/microbiologia , Fenótipo , Reação em Cadeia da Polimerase , Fatores de Virulência/genética
15.
Eur J Med Chem ; 205: 112645, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32791399

RESUMO

Ergosterol as the core component of fungal cell membrane plays a key role in maintaining cell morphology and permeability. The squalenee epoxidase (SE) and 14-demethylase (CYP51) are the important rate-limiting enzymes for ergosterol synthesis. In the study, these active fragments, which is derived from the structural groups of the common antifungal agents, were docked into the active sites of dual targets (SE, CYP51), respectively. Some of active fragments with the matching MCSS_Score values were selected and connected to construct three different series of novel arylalkene-amide derivatives as dual-target (SE, CYP51) antifungal inhibitors. Subsequently, these compounds were further synthesized, and their bioactivity was evaluated. Most of compounds showed a certain degree of antifungal activity in vitro. It was worth noting that the target compounds 17a and 25a with excellent antifungal activity (0.125-4 µg/mL) can inhibit the fluconazole-resistant Candida Strain 17#, CaR, 632, and 901 in the range of MIC values (4-8 µg/mL). Furthermore, their molecular mechanism, structural stability and low toxicity were further confirmed. The molecular docking and ADMET properties were predicted to guide the subsequent optimization of target compounds.


Assuntos
Alcenos/química , Amidas/síntese química , Amidas/farmacologia , Antifúngicos/síntese química , Antifúngicos/farmacologia , Desenho de Fármacos , Inibidores de 14-alfa Desmetilase/síntese química , Inibidores de 14-alfa Desmetilase/química , Inibidores de 14-alfa Desmetilase/farmacologia , Amidas/química , Antifúngicos/química , Candida/efeitos dos fármacos , Candida/enzimologia , Técnicas de Química Sintética , Testes de Sensibilidade Microbiana , Simulação de Acoplamento Molecular , Terapia de Alvo Molecular , Conformação Proteica , Esqualeno Mono-Oxigenase/antagonistas & inibidores , Esqualeno Mono-Oxigenase/química , Esqualeno Mono-Oxigenase/metabolismo , Esterol 14-Desmetilase
16.
Dalton Trans ; 49(32): 11059-11072, 2020 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-32808625

RESUMO

Enzymes exhibit a large degree of compatibility with metal-organic frameworks (MOFs) which allows the development of multicomponent catalysts consisting of enzymes adsorbed or occluded by MOFs. The combination of enzymes and MOFs in a multicomponent catalyst can be used to promote cascade reactions in which two or more individual reactions are performed in a single step. Cascade reactions take place due to the cooperation of active sites present on the MOF with the enzyme. A survey of the available data establishes that often an enzyme undergoes stabilization by association with a MOF and the system exhibits notable recyclability. In addition, the existence of synergism is observed as a consequence of the close proximity of all the required active sites in the multicomponent catalyst. After an introductory section describing the specific features and properties of enzyme-MOF assemblies, the main part of the present review focuses on the description of the cascade reactions that have been reported with commercial enzymes associated with MOFs, paying special attention to the advantages derived from the multicomponent catalyst. Related to the catalytic activity to metabolize glucose, generating reactive oxygen species (ROS) and decreasing the solution pH, an independent section describes the recent use of enzyme-MOF catalysts in cancer therapy. The last paragraphs summarize the current state of the art and provide our view on future developments in this field.


Assuntos
Estruturas Metalorgânicas/química , Neoplasias/tratamento farmacológico , Esterol Esterase/química , Candida/enzimologia , Catálise , Morte Celular/efeitos dos fármacos , Humanos , Estruturas Metalorgânicas/metabolismo , Estruturas Metalorgânicas/farmacologia , Neoplasias/metabolismo , Neoplasias/patologia , Esterol Esterase/metabolismo
17.
Bioprocess Biosyst Eng ; 43(11): 2085-2093, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32601811

RESUMO

The active site of Candida rugosa lipase (CRL) is mainly hydrophilic on its external face and hydrophobic on the internal side, and calix[n]arene-based surfactants form complexes with protein residues or with strong hydrogen bonds to open up the lid. Therefore, the activity of lipase persists for a long time. In this work, a series of cyclic and acyclic anionic surfactants (sodium dodecyl sulfate (SDS), p-sulfonatocalix[4]arene, and p-sulfonatocalix[8]arene) and zwitterionic surfactants (L-proline and L-proline derivative of calix[4]arene) were used to examine the relationship between the surfactants' molecular structures and their effects on the hydrolytic activity of CRL. We explored the effects of different surfactant concentrations, ring effects, and mixing times on CRL activity and several kinetic parameters. The results demonstrated that cyclic compounds were more effective than linear structures for increasing CRL activity and the highest enzyme activity was obtained by the addition of the calix[4]-L-proline derivative. This zwitterionic compound (calix[4]-L-proline derivative) maintains the active center of enzyme and conformation by enabling electrostatic interactions and hydrogen bonding with both the acidic and basic amino acid groups in the structure of the enzyme. The results indicated that, compared with the other surfactants, activating CRL with calix[4]-L-proline resulted in hyperactivation at all concentrations (a relative increase of 230%).


Assuntos
Lipase/antagonistas & inibidores , Saccharomycetales/efeitos dos fármacos , Saccharomycetales/enzimologia , Tensoativos/química , Ânions , Biocatálise , Calixarenos/química , Candida/enzimologia , Domínio Catalítico , Detergentes , Enzimas Imobilizadas/química , Ligação de Hidrogênio , Concentração de Íons de Hidrogênio , Hidrólise , Cinética , Espectroscopia de Ressonância Magnética , Fenóis/química , Prolina/química , Dodecilsulfato de Sódio/química , Eletricidade Estática , Estereoisomerismo
18.
Int J Biol Macromol ; 164: 1-12, 2020 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-32679334

RESUMO

This paper has focused on making suitable carriers for the immobilization of α-amylase from Bacillus subtilis and lipase from Candida rugosa via adsorption on modified Na-sepiolite (SEP). Two modified carriers were prepared by changing the nature of SEP with cetrimonium bromide surfactant at concentrations below the CMC of the surfactant, to produce SEP with monolayer surfactant (MSEP) with hydrophobic properties and above the CMC of the surfactant to produce SEP with bilayer surfactant (BSEP) with hydrophilic properties. The enzymatic activity of immobilized lipase on MSEP (MSEPL) and immobilized α-amylase on BSEP (BSEPA) was successfully tested in the hydrolysis of olive oil and starch. The support modification and immobilization process were characterized by BET, XRD, and SEM techniques. The results demonstrated that the specific activity of MSEPL and BSEPA was 1.74 and 2.28 U/mg, respectively. The remained activity of MSEPL (56.7%) and BSEPA (40.4%) after their incubation at 60 °C for 4 h was much higher than that of free enzymes. The residual activity of MSEPL and BSEPA was 77.4% and 66.7%, after 30 days of storage at 4 °C. The MSEPL and BSEPA also showed good reusability, and their relative activities were 54.0% and 44.2% after ten cycles.


Assuntos
Enzimas Imobilizadas/química , Lipase , Silicatos de Magnésio/química , alfa-Amilases , Adsorção , Bacillus subtilis/enzimologia , Proteínas de Bactérias/química , Biocatálise , Candida/enzimologia , Cetrimônio/química , Estabilidade Enzimática , Proteínas Fúngicas/química , Concentração de Íons de Hidrogênio , Interações Hidrofóbicas e Hidrofílicas , Lipase/metabolismo , Microscopia Eletrônica de Varredura , Azeite de Oliva/metabolismo , Amido/metabolismo , Propriedades de Superfície , Tensoativos/química , Temperatura , alfa-Amilases/metabolismo
19.
Biotechnol Lett ; 42(11): 2157-2167, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32661656

RESUMO

OBJECTIVE: To evaluate the catalytic esterification performance of proteases in micro-aqueous systems and to study the suitable conditions for maintaining protease activity. RESULTS: It was found that the protease showed better enzyme catalytic activity in the micro-aqueous phase containing 4% boric acid-borax buffer than that of the pure organic phase. The protease activity was easily activated by 0.20 M boric acid-borax buffer, and the enzyme activity was still high for a long time in alkaline environment (pH 8.40-9.60) and under the temperature of 40-55 °C. Experiments using protease and Candida lipase to synthesize sucrose-6-ethyl ester showed that protease had better esterification activity than Candida lipase in the micro-aqueous phase.


Assuntos
Bacillus subtilis/enzimologia , Ácidos Bóricos/química , Peptídeo Hidrolases/metabolismo , Sacarose/metabolismo , Proteínas de Bactérias/metabolismo , Candida/enzimologia , Catálise , Ativação Enzimática , Esterificação , Proteínas Fúngicas/metabolismo , Temperatura Alta , Concentração de Íons de Hidrogênio , Lipase/metabolismo , Solventes/química , Sacarose/química , Água
20.
Lett Appl Microbiol ; 71(4): 413-419, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32623751

RESUMO

As a result of electron microscopic studies of morphogenesis in yeast Candida guilliermondii NP-4, the formation of new structures of volutin acidocalcisomes has been established within the cell cytoplasm. Under influence of X-irradiation, the changes in morphometric and electron-dense properties of yeast cells were identified: in yeast cytoplasm, the electron-dense volutin granules were increased up to 400 nm in size. After 24-h post-irradiation incubation of yeasts, the large volutin pellets are fragmented into smaller number particles in size up to 25-150 nm. The ATPase activity in yeast mitochondria was changed under X-irradiation. In latent phase of growth, ATPase activity was decreased 1·35-fold in comparison with non-irradiated yeasts. In logarithmic phase of growth, ATPase activity was three times higher than in latent phase, and in stationary phase of growth it has a value similar to the latent phase. Probably, the cells receive the necessary energy from alternative energy sources, such as volutin. Electron microscopy of volutin granule changes might serve as convenient method for evaluation of damages and repair processes in cells under influence of different environmental stress-factors.


Assuntos
Adenosina Trifosfatases/metabolismo , Candida/efeitos da radiação , Candida/ultraestrutura , Proteínas Fúngicas/metabolismo , Organelas/enzimologia , Adenosina Trifosfatases/genética , Adenosina Trifosfatases/ultraestrutura , Trifosfato de Adenosina/metabolismo , Candida/enzimologia , Candida/genética , Proteínas Fúngicas/química , Proteínas Fúngicas/genética , Organelas/genética , Organelas/efeitos da radiação , Organelas/ultraestrutura , Raios X
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