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1.
Plant Physiol Biochem ; 214: 108939, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39029309

RESUMO

GDSL-type esterase/lipase protein (GELP) genes are crucial in the specialized lipid metabolism, in the responses to abiotic stresses, and in the regulation of plant homeostasis. R. communis is an important oilseed crop species that can sustain growth and productivity when exposed to harsh environmental conditions. Herein, we raised the question of whether the GELP gene family could be involved in the acquisition of R. communis tolerance to abiotic stresses during seed germination and seedling establishment. Thus, we used bioinformatics and transcriptomics to characterize the R. communis GELP gene family. R. communis genome possesses 96 GELP genes that were characterized by extensive bioinformatics, including phylogenetic analysis, subcellular localization, exon-intron distribution, the analysis of regulatory cis-elements, tandem duplication, and physicochemical properties. Transcriptomics indicated that numerous RcGELP genes are readily responsive to high-temperature and salt stresses and might be potential candidates for genome editing techniques to develop abiotic stress-tolerant crops.


Assuntos
Regulação da Expressão Gênica de Plantas , Germinação , Proteínas de Plantas , Ricinus , Plântula , Estresse Fisiológico , Plântula/genética , Plântula/crescimento & desenvolvimento , Estresse Fisiológico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Germinação/genética , Ricinus/genética , Ricinus/metabolismo , Esterases/genética , Esterases/metabolismo , Filogenia , Lipase/genética , Lipase/metabolismo , Família Multigênica , Genoma de Planta/genética
2.
Mol Biol Rep ; 51(1): 767, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38878205

RESUMO

BACKGROUND: Esterases (EC 3.1.1.X) are enzymes that catalyze the hydrolysis ester bonds. These enzymes have large potential for diverse applications in fine industries, particularly in pharmaceuticals, cosmetics, and bioethanol production. METHODS AND RESULTS: In this study, a gene encoding an esterase from Thermobifida fusca YX (TfEst) was successfully cloned, and its product was overexpressed in Escherichia coli and purified using affinity chromatography. The TfEst kinetic assay revealed catalytic efficiencies of 0.58 s-1 mM-1, 1.09 s-1 mM-1, and 0.062 s-1 mM-1 against p-Nitrophenyl acetate, p-Nitrophenyl butyrate, and 1-naphthyl acetate substrates, respectively. Furthermore, TfEst also exhibited activity in a pH range from 6.0 to 10.0, with maximum activity at pH 8.0. The enzyme demonstrated a half-life of 20 min at 70 °C. Notably, TfEst displayed acetyl xylan esterase activity as evidenced by the acetylated xylan assay. The structural prediction of TfEst using AlphaFold indicated that has an α/ß-hydrolase fold, which is consistent with other esterases. CONCLUSIONS: The enzyme stability over a broad pH range and its activity at elevated temperatures make it an appealing candidate for industrial processes. Overall, TfEst emerges as a promising enzymatic tool with significant implications for the advancement of biotechnology and biofuels industries.


Assuntos
Acetilesterase , Esterases , Thermobifida , Acetilesterase/metabolismo , Acetilesterase/genética , Acetilesterase/química , Concentração de Íons de Hidrogênio , Cinética , Especificidade por Substrato , Thermobifida/enzimologia , Thermobifida/genética , Esterases/metabolismo , Esterases/genética , Esterases/química , Estabilidade Enzimática , Temperatura , Escherichia coli/genética , Escherichia coli/metabolismo , Clonagem Molecular/métodos , Hidrólise , Xilanos/metabolismo , Butiratos/metabolismo , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética , Proteínas de Bactérias/química , Nitrofenóis
3.
Biochemistry ; 63(9): 1178-1193, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38669355

RESUMO

Herein, we present a novel esterase enzyme, Ade1, isolated from a metagenomic library of Amazonian dark earths soils, demonstrating its broad substrate promiscuity by hydrolyzing ester bonds linked to aliphatic groups. The three-dimensional structure of the enzyme was solved in the presence and absence of substrate (tributyrin), revealing its classification within the α/ß-hydrolase superfamily. Despite being a monomeric enzyme, enzymatic assays reveal a cooperative behavior with a sigmoidal profile (initial velocities vs substrate concentrations). Our investigation brings to light the allokairy/hysteresis behavior of Ade1, as evidenced by a transient burst profile during the hydrolysis of substrates such as p-nitrophenyl butyrate and p-nitrophenyl octanoate. Crystal structures of Ade1, coupled with molecular dynamics simulations, unveil the existence of multiple conformational structures within a single molecular state (E̅1). Notably, substrate binding induces a loop closure that traps the substrate in the catalytic site. Upon product release, the cap domain opens simultaneously with structural changes, transitioning the enzyme to a new molecular state (E̅2). This study advances our understanding of hysteresis/allokairy mechanisms, a temporal regulation that appears more pervasive than previously acknowledged and extends its presence to metabolic enzymes. These findings also hold potential implications for addressing human diseases associated with metabolic dysregulation.


Assuntos
Esterases , Simulação de Dinâmica Molecular , Esterases/química , Esterases/metabolismo , Esterases/genética , Especificidade por Substrato , Domínio Catalítico , Cristalografia por Raios X , Conformação Proteica , Hidrólise , Cinética , Modelos Moleculares
4.
Sci Rep ; 11(1): 10440, 2021 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-34001974

RESUMO

Metagenomic data mining of the Nellore cattle rumen microbiota identified a new bifunctional enzyme, endo-1,4-ß-xylanase/esterase, which was subsequently overexpressed in E. coli BL21 (DE3). This enzyme was stable at pH intervals of 5 to 6.5 and temperatures between 30 and 45 °C, and under the test conditions, it had a Vmax of 30.959 ± 2.334 µmol/min/mg, Km of 3.6 ± 0.6 mM and kcat of 2.323 ± 175 s-1. Additionally, the results showed that the enzyme is tolerant to NaCl and organic solvents and therefore is suitable for industrial environments. Xylanases are widely applicable, and the synergistic activity of endo-1,4-ß-xylanase/esterase in a single molecule will improve the degradation efficiency of heteroxylans via the creation of xylanase binding sites. Therefore, this new molecule has the potential for use in lignocellulosic biomass processing and as an animal feed food additive and could improve xylooligosaccharide production efficiency.


Assuntos
Proteínas de Bactérias/metabolismo , Endo-1,4-beta-Xilanases/metabolismo , Esterases/metabolismo , Microbioma Gastrointestinal , Rúmen/microbiologia , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/isolamento & purificação , Bovinos , Endo-1,4-beta-Xilanases/genética , Endo-1,4-beta-Xilanases/isolamento & purificação , Ensaios Enzimáticos , Esterases/genética , Esterases/isolamento & purificação , Glucuronatos/biossíntese , Microbiologia Industrial/métodos , Lignina/metabolismo , Metagenoma , Oligossacarídeos/biossíntese , Proteínas Recombinantes/genética , Proteínas Recombinantes/isolamento & purificação , Proteínas Recombinantes/metabolismo , Energia Renovável
5.
Mol Biotechnol ; 63(3): 184-199, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33484441

RESUMO

Heterologous expression of the carbohydrate-active enzymes in microorganisms is a promising approach to produce bio-based compounds, such as fuels, nutraceuticals and other value-added products from sustainable lignocellulosic sources. Several microorganisms, including Saccharomyces cerevisiae, Escherichia coli, and the filamentous fungi Aspergillus nidulans, have unique characteristics desirable for a biorefinery production approach like well-known genetic tools, thermotolerance, high fermentative capacity and product tolerance, and high amount of recombinant enzyme secretion. These microbial factories are already stablished in the heterologous production of the carbohydrate-active enzymes to produce, among others, ethanol, xylooligosaccharides and the valuable coniferol. A complete biocatalyst able to heterologous express the CAZymes of glycoside hydrolases, carbohydrate esterases and auxiliary activities families could release these compounds faster, with higher yield and specificity. Recent advances in the synthetic biology tools could expand the number and diversity of enzymes integrated in these microorganisms, and also modify those already integrated. This review outlines the heterologous expression of carbohydrate-active enzymes in microorganisms, as well as recent updates in synthetic biology.


Assuntos
Bactérias/crescimento & desenvolvimento , Fungos/crescimento & desenvolvimento , Lignina/metabolismo , Engenharia de Proteínas/métodos , Bactérias/genética , Produtos Biológicos/metabolismo , Esterases/genética , Esterases/metabolismo , Fungos/genética , Glicosídeo Hidrolases/genética , Glicosídeo Hidrolases/metabolismo , Biologia Sintética
6.
Int J Food Microbiol ; 309: 108312, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31499265

RESUMO

The characteristics and quality of home-made dry cured sausages can be recognized and associated with the region of origin. The characteristics of this type of sausages result from the superficial mycobiota that spontaneously colonizes the products. The aim of this study was to identify the house mycobiota associated with home-made dry cured sausages from different localities of Argentina and characterize the populations of Penicillium nalgiovense present by morphological and biochemical markers. To this end, 79 samples were collected from 10 localities of three main producing regions (Buenos Aires, Córdoba and La Pampa provinces). A total of 196 isolates belonging to six genera and 17 species were obtained. The predominant genus was Penicillium (134 of the isolates) and the predominant species was P. nalgiovense (108 isolates). The isoenzyme patterns of α-esterase (α-EST; EC 3.1.1.1) and Malate dehydrogenase NADP+(MDHP; EC 1.1.1.40) were characterized in 48 of these isolates (ten from Colonia Caroya, ten from Oncativo, ten from Tandil, nine from Mercedes and nine from La Pampa). A total of 26 bands were observed: 17 for α-EST and 9 for MDHP. α-EST was the most polymorphic isoenzyme, whereas MDPH presented no polymorphism. The results were subjected to numerical analysis. Cluster analysis revealed the formation of two groups: Group I formed by 24 isolates from Córdoba and Buenos Aires provinces and Group II with 24 isolates from La Pampa and Buenos Aires province. These data suggest the existence of morphological and biochemical variations among P. nalgiovense populations with different geographical origin.


Assuntos
Produtos da Carne/microbiologia , Penicillium/classificação , Penicillium/isolamento & purificação , Argentina , Esterases/genética , Fermentação , Contaminação de Alimentos/análise , Malato Desidrogenase/genética , Penicillium/genética
7.
Arch Microbiol ; 201(8): 1147-1149, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31147748

RESUMO

Non-albicans Candida species have acquired relevance in the last decades as a cause of serious disease. The virulence factors and antifungal susceptibility of these rare pathogens remain largely unrecognized. We examined a total of 50 yeast isolates corresponding to 11 different infrequently isolated yeast species for their in vitro enzymatic profile and susceptibility pattern as first-line antifungals. We found aspartyl protease activity for 100% of the isolates tested as well as variable DNAse, hemolysin, phospholipase and esterase activities. All strains had low MICs for amphotericin B and showed a variable response to fluconazole (0.125-32 µg/mL) and the echinocandins tested (0.25-> 8 µg/mL).


Assuntos
Anfotericina B/farmacologia , Antifúngicos/farmacologia , Candida/efeitos dos fármacos , Candida/genética , Equinocandinas/farmacologia , Fluconazol/farmacologia , Ácido Aspártico Proteases/genética , Candida/classificação , Candida/isolamento & purificação , Desoxirribonucleases/genética , Esterases/genética , Proteínas Hemolisinas/genética , Humanos , Testes de Sensibilidade Microbiana , Fosfolipases/genética , Fatores de Virulência , Leveduras/classificação , Leveduras/efeitos dos fármacos , Leveduras/isolamento & purificação
8.
Curr Genet ; 65(6): 1367-1381, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31104082

RESUMO

Bacteria of the Bacillus cereus group colonize several ecological niches and infect different hosts. Bacillus cereus, a ubiquitous species causing food poisoning, Bacillus thuringiensis, an entomopathogen, and Bacillus anthracis, which is highly pathogenic to mammals, are the most important species of this group. These species are closely related genetically, and their specific toxins are encoded by plasmids. The infectious cycle of B. thuringiensis in its insect host is regulated by quorum-sensing systems from the RNPP family. Among them, the Rap-Phr systems, which are well-described in Bacillus subtilis, regulate essential processes, such as sporulation. Given the importance of these systems, we performed a global in silico analysis to investigate their prevalence, distribution, diversity and their role in sporulation in B. cereus group species. The rap-phr genes were identified in all selected strains with 30% located on plasmids, predominantly in B. thuringiensis. Despite a high variability in their sequences, there is a remarkable association between closely related strains and their Rap-Phr profile. Based on the key residues involved in RapH phosphatase activity, we predicted that 32% of the Rap proteins could regulate sporulation by preventing the phosphorylation of Spo0F. These Rap are preferentially located on plasmids and mostly related to B. thuringiensis. The predictions were partially validated by in vivo sporulation experiments suggesting that the residues linked to the phosphatase function are necessary but not sufficient to predict this activity. The wide distribution and diversity of Rap-Phr systems could strictly control the commitment to sporulation and then improve the adaptation capacities of the bacteria to environmental changes.


Assuntos
Bacillus cereus/genética , Proteínas de Bactérias/genética , Fosfoproteínas Fosfatases/genética , Percepção de Quorum/genética , Bacillus cereus/enzimologia , Bacillus cereus/metabolismo , Bacillus subtilis/enzimologia , Bacillus subtilis/genética , Bacillus thuringiensis/enzimologia , Bacillus thuringiensis/genética , Proteínas de Bactérias/metabolismo , Análise por Conglomerados , Esterases/genética , Esterases/metabolismo , Peptídeos/química , Fosfoproteínas Fosfatases/metabolismo , Filogenia , Plasmídeos/genética , Plasmídeos/metabolismo , Percepção de Quorum/fisiologia , Esporos Bacterianos/genética , Esporos Bacterianos/metabolismo
9.
Braz J Microbiol ; 50(3): 619-624, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31001795

RESUMO

Burkholderia contaminans LTEB11 is a Gram-negative betaproteobacterium isolated as a contaminant of a culture in mineral medium supplemented with vegetable oil. Here, we report the genome sequence of B. contaminans LTEB11, identifying and analyzing the genes involved in its lipolytic machinery and in the production of other biotechnological products.


Assuntos
Burkholderia/genética , Genoma Bacteriano , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biotecnologia , Burkholderia/classificação , Burkholderia/enzimologia , Burkholderia/metabolismo , Esterases/genética , Esterases/metabolismo , Lipase/genética , Lipase/metabolismo , Análise de Sequência de DNA
10.
Insect Sci ; 26(5): 809-820, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-29611294

RESUMO

Although having five different ways of transmission the vector-borne is the principal way of transmission of Chagas disease, which involves insects of the subfamily Triatominae (Hemiptera: Reduviidae). Nineteen of the 31 species that occur in Mexico are associated with humans, and all are capable of transmitting the disease. Pyrethroids are the insecticides recommended for the control of these vectors in Mexico. We determined the susceptibility to the pyrethroids deltamethrin and permethrin of peridomestic populations of Triatoma mazzottii Usinger and two populations of Triatoma longipennis Usinger in comparison with a reference strain for each species. Bioassays were performed for the determination of the LD50 for both field populations and reference strains. A maximum of 27 fold resistance to deltamethrin was observed in T. mazzottii, meanwhile, for permethrin, T. longipennis from Jalisco show the highest value of 3.19 fold. There was significantly increased activity of esterases in field populations in comparison with their corresponding reference strain. The results of the search of kdr mutations related to the resistance to deltamethrin and permethrin in the evaluated species show the presence of mutations in the field populations, as is the case with individuals of T. mazzottii, for which the mutation was found A943V, and for the two populations of T. longipennis included in this study, we report the presence of the kdr mutation K964R. Evaluation of the various mechanisms involved in resistance to pyrethroids in triatomines from Mexico could guide us to the real justification for insecticide resistance monitoring.


Assuntos
Resistência a Inseticidas , Nitrilas , Permetrina , Piretrinas , Triatoma/genética , Animais , Esterases/genética , Esterases/metabolismo , Inativação Metabólica/genética , Insetos Vetores/genética , Dose Letal Mediana , México , Mutação , Triatoma/enzimologia
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