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1.
Sci Total Environ ; 951: 175651, 2024 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-39168331

RESUMEN

Food waste (FW) comprises carbohydrates, proteins, lipids, and water, posing technical challenges for effective treatment and valorisation. This study addresses these challenges by using black soldier fly larvae (BSFL) as a bioconversion medium to transform FW into biodiesel (BD). BSFL predominantly consumed the carbohydrates and proteins in FW (81 wt%), while showing a lower preference for lipids (<50 wt% consumed). Notwithstanding the lower consumption of lipids in the FW than that of carbohydrates and proteins, BSFL had a high lipid content (48.3 wt%). The subsequent conversion of the lipids extracted from BSFL into BD was tested via catalytic (acid/alkali) and non-catalytic transesterification processes. The BD yield from catalytic transesterification was lower than that from non-catalytic transesterification because of the low tolerance against free fatty acids (FFAs). BD was also produced from the lipid-concentrated residual FW through non-catalytic transesterification. Although the FW residue extracts contained high amounts of FFAs (49.9 wt%), non-catalytic transesterification displayed a high BD yield (92.4 wt%; yields from catalytic transesterification: < 80.0 wt%). Moreover, blending the BD derived from the BSFL and FW residue extracts enhanced the fuel properties. The BSFL-assisted FW management efficiently reduced FW by 90 wt% while producing a high-quality BD.


Asunto(s)
Biocombustibles , Larva , Animales , Esterificación , Dípteros , Simuliidae , Alimento Perdido y Desperdiciado
2.
Oncol Rep ; 52(4)2024 10.
Artículo en Inglés | MEDLINE | ID: mdl-39054954

RESUMEN

Zinc finger protein 180 (ZNF180) is a multifunctional protein that interacts with nucleic acids and regulates various cellular processes; however, the function of ZNF180 in colorectal cancer (CRC) remains unclear. The present study investigated the role and function of ZNF180 in CRC, and aimed to reveal the underlying molecular mechanism. The results revealed that ZNF180 was downregulated in CRC tissues and was associated with a good prognosis in patients with CRC. Additionally, the expression of ZNF180 was downregulated by methylation in CRC. In vivo and in vitro experiments revealed that ZNF180 overexpression was functionally associated with the inhibition of cell proliferation and the induction of apoptosis. Mechanistically, chromatin immunoprecipitation­PCR and luciferase assays demonstrated that ZNF180 markedly regulated the transcriptional activity of methyltransferase 14, N6­adenosine­methyltransferase non­catalytic subunit (METTL14) by directly binding to and activating its promoter region. Simultaneous overexpression of ZNF180 and knockdown of METTL14 indicated that the reduction of METTL14 could suppress the effects of ZNF180 on the induction of apoptosis. Clinically, the present study observed a significant positive correlation between ZNF180 and METTL14 expression levels, and low expression of ZNF180 and METTL14 predicted a poor prognosis in CRC. Overall, these findings revealed a novel mechanism by which the ZNF180/METTL14 axis may modulate apoptosis and cell proliferation in CRC. This evidence suggests that this axis may serve as a prognostic biomarker and therapeutic target in patients with CRC.


Asunto(s)
Apoptosis , Proliferación Celular , Neoplasias Colorrectales , Regulación Neoplásica de la Expresión Génica , Metiltransferasas , Humanos , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/metabolismo , Metiltransferasas/genética , Metiltransferasas/metabolismo , Apoptosis/genética , Proliferación Celular/genética , Masculino , Femenino , Pronóstico , Persona de Mediana Edad , Línea Celular Tumoral , Animales , Activación Transcripcional , Ratones , Regiones Promotoras Genéticas , Anciano , Regulación hacia Abajo , Metilación de ADN
3.
Mol Cell ; 84(14): 2732-2746.e5, 2024 Jul 25.
Artículo en Inglés | MEDLINE | ID: mdl-38981483

RESUMEN

Metabolic enzymes can adapt during energy stress, but the consequences of these adaptations remain understudied. Here, we discovered that hexokinase 1 (HK1), a key glycolytic enzyme, forms rings around mitochondria during energy stress. These HK1-rings constrict mitochondria at contact sites with the endoplasmic reticulum (ER) and mitochondrial dynamics protein (MiD51). HK1-rings prevent mitochondrial fission by displacing the dynamin-related protein 1 (Drp1) from mitochondrial fission factor (Mff) and mitochondrial fission 1 protein (Fis1). The disassembly of HK1-rings during energy restoration correlated with mitochondrial fission. Mechanistically, we identified that the lack of ATP and glucose-6-phosphate (G6P) promotes the formation of HK1-rings. Mutations that affect the formation of HK1-rings showed that HK1-rings rewire cellular metabolism toward increased TCA cycle activity. Our findings highlight that HK1 is an energy stress sensor that regulates the shape, connectivity, and metabolic activity of mitochondria. Thus, the formation of HK1-rings may affect mitochondrial function in energy-stress-related pathologies.


Asunto(s)
Dinaminas , Metabolismo Energético , Hexoquinasa , Mitocondrias , Dinámicas Mitocondriales , Proteínas Mitocondriales , Hexoquinasa/metabolismo , Hexoquinasa/genética , Humanos , Mitocondrias/metabolismo , Mitocondrias/genética , Mitocondrias/enzimología , Dinaminas/metabolismo , Dinaminas/genética , Proteínas Mitocondriales/metabolismo , Proteínas Mitocondriales/genética , Animales , Adenosina Trifosfato/metabolismo , Estrés Fisiológico , Retículo Endoplásmico/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética , Ciclo del Ácido Cítrico , Glucosa-6-Fosfato/metabolismo , Ratones , Células HeLa , Células HEK293 , GTP Fosfohidrolasas/metabolismo , GTP Fosfohidrolasas/genética , Mutación
4.
Curr Opin Chem Biol ; 81: 102476, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38861851

RESUMEN

O-GlcNAcylation is an essential protein glycosylation governed by two O-GlcNAc cycling enzymes: O-GlcNAc transferase (OGT) installs a single sugar moiety N-acetylglucosamine (GlcNAc) on protein serine and threonine residues, and O-GlcNAcase (OGA) removes them. Aberrant O-GlcNAcylation has been implicated in various diseases. However, the large repertoire of more than 1000 O-GlcNAcylated proteins and the elusive mechanisms of OGT/OGA in substrate recognition present significant challenges in targeting the dysregulated O-GlcNAcylation for therapeutic development. Recently, emerging evidence suggested that the non-catalytic domains play critical roles in regulating the functional specificity of OGT/OGA via modulating their protein interactions and substrate recognition. Here, we discuss recent studies on the structures, mechanisms, and related tools of the OGT/OGA non-catalytic domains, highlighting new opportunities for function-specific control.


Asunto(s)
Acetilglucosamina , N-Acetilglucosaminiltransferasas , beta-N-Acetilhexosaminidasas , N-Acetilglucosaminiltransferasas/metabolismo , N-Acetilglucosaminiltransferasas/química , Humanos , Acetilglucosamina/metabolismo , Acetilglucosamina/química , beta-N-Acetilhexosaminidasas/metabolismo , beta-N-Acetilhexosaminidasas/química , Especificidad por Sustrato , Animales , Glicosilación , Dominios Proteicos
5.
Int J Cancer ; 155(6): 1128-1138, 2024 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-38676430

RESUMEN

Disease progression is a major problem in ovarian cancer. There are very few treatment options for patients with platinum-resistant ovarian cancer (PROC), and therefore, these patients have a particularly poor prognosis. The aim of the present study was to identify markers for monitoring the response of 123 PROC patients enrolled in the Phase I/II GANNET53 clinical trial, which evaluated the efficacy of Ganetespib in combination with standard chemotherapy versus standard chemotherapy alone. In total, 474 blood samples were collected, comprising baseline samples taken before the first administration of the study drugs and serial samples taken during treatment until further disease progression (PD). After microfluidic enrichment, 27 gene transcripts were analyzed using quantitative polymerase chain reaction and their utility for disease monitoring was evaluated. At baseline, ERCC1 was associated with an increased risk of PD (hazard ratio [HR] 1.75, 95% confidence interval [CI]: 1.20-2.55; p = 0.005), while baseline CDH1 and ESR1 may have a risk-reducing effect (CDH1 HR 0.66, 95% CI: 0.46-0.96; p = 0.024; ESR1 HR 0.58, 95% CI: 0.39-0.86; p = 0.002). ERCC1 was observed significantly more often (72.7% vs. 53.9%; p = 0.032) and ESR1 significantly less frequently (59.1% vs. 78.3%; p = 0.018) in blood samples taken at radiologically confirmed PD than at controlled disease. At any time during treatment, ERCC1-presence and ESR1-absence were associated with short PFS and with higher odds of PD within 6 months (odds ratio 12.77, 95% CI: 4.08-39.97; p < 0.001). Our study demonstrates the clinical relevance of ESR1 and ERCC1 and may encourage the analysis of liquid biopsy samples for the management of PROC patients.


Asunto(s)
Biomarcadores de Tumor , Resistencia a Antineoplásicos , Endonucleasas , Neoplasias Ováricas , Humanos , Femenino , Neoplasias Ováricas/tratamiento farmacológico , Neoplasias Ováricas/genética , Neoplasias Ováricas/sangre , Neoplasias Ováricas/patología , Resistencia a Antineoplásicos/genética , Endonucleasas/genética , Persona de Mediana Edad , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/sangre , Anciano , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/sangre , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Receptor alfa de Estrógeno/genética , Adulto , Pronóstico , Progresión de la Enfermedad , Regulación Neoplásica de la Expresión Génica , Platino (Metal)/uso terapéutico
6.
Elife ; 132024 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-38687676

RESUMEN

Regulated hydrolysis of the phosphoinositide phosphatidylinositol(4,5)-bis-phosphate to diacylglycerol and inositol-1,4,5-P3 defines a major eukaryotic pathway for translation of extracellular cues to intracellular signaling circuits. Members of the lipid-activated protein kinase C isoenzyme family (PKCs) play central roles in this signaling circuit. One of the regulatory mechanisms employed to downregulate stimulated PKC activity is via a proteasome-dependent degradation pathway that is potentiated by peptidyl-prolyl isomerase Pin1. Here, we show that contrary to prevailing models, Pin1 does not regulate conventional PKC isoforms α and ßII via a canonical cis-trans isomerization of the peptidyl-prolyl bond. Rather, Pin1 acts as a PKC binding partner that controls PKC activity via sequestration of the C-terminal tail of the kinase. The high-resolution structure of full-length Pin1 complexed to the C-terminal tail of PKCßII reveals that a novel bivalent interaction mode underlies the non-catalytic mode of Pin1 action. Specifically, Pin1 adopts a conformation in which it uses the WW and PPIase domains to engage two conserved phosphorylated PKC motifs, the turn motif and hydrophobic motif, respectively. Hydrophobic motif is a non-canonical Pin1-interacting element. The structural information combined with the results of extensive binding studies and experiments in cultured cells suggest that non-catalytic mechanisms represent unappreciated modes of Pin1-mediated regulation of AGC kinases and other key enzymes/substrates.


Asunto(s)
Peptidilprolil Isomerasa de Interacción con NIMA , Unión Proteica , Peptidilprolil Isomerasa de Interacción con NIMA/metabolismo , Peptidilprolil Isomerasa de Interacción con NIMA/química , Peptidilprolil Isomerasa de Interacción con NIMA/genética , Humanos , Proteína Quinasa C/metabolismo , Proteína Quinasa C/química , Proteína Quinasa C/genética , Conformación Proteica
7.
Front Mol Biosci ; 11: 1349509, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38455765

RESUMEN

Proteases that cleave ubiquitin or ubiquitin-like proteins (UBLs) are critical players in maintaining the homeostasis of the organism. Concordantly, their dysregulation has been directly linked to various diseases, including cancer, neurodegeneration, developmental aberrations, cardiac disorders and inflammation. Given their potential as novel therapeutic targets, it is essential to fully understand their mechanisms of action. Traditionally, observed effects resulting from deficiencies in deubiquitinases (DUBs) and UBL proteases have often been attributed to the misregulation of substrate modification by ubiquitin or UBLs. Therefore, much research has focused on understanding the catalytic activities of these proteins. However, this view has overlooked the possibility that DUBs and UBL proteases might also have significant non-catalytic functions, which are more prevalent than previously believed and urgently require further investigation. Moreover, multiple examples have shown that either selective loss of only the protease activity or complete absence of these proteins can have different functional and physiological consequences. Furthermore, DUBs and UBL proteases have been shown to often contain domains or binding motifs that not only modulate their catalytic activity but can also mediate entirely different functions. This review aims to shed light on the non-catalytic, moonlighting functions of DUBs and UBL proteases, which extend beyond the hydrolysis of ubiquitin and UBL chains and are just beginning to emerge.

8.
Drug Resist Updat ; 71: 100992, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37567064

RESUMEN

ATP-binding cassette (ABC) superfamily comprises a large group of ubiquitous transmembrane proteins that play a crucial role in transporting a diverse spectrum of substrates across cellular membranes. They participate in a wide array of physiological and pathological processes including nutrient uptake, antigen presentation, toxin elimination, and drug resistance in cancer and microbial cells. ABC transporters couple ATP binding and hydrolysis to undergo conformational changes allowing substrate translocation. Within this superfamily, a set of ABC transporters has lost the capacity to hydrolyze ATP at one of their nucleotide-binding sites (NBS), called the non-catalytic NBS, whose importance became evident with extensive biochemistry carried out on yeast pleiotropic drug resistance (PDR) transporters. Recent single-particle cryogenic electron microscopy (cryo-EM) advances have further catapulted our understanding of the architecture of these pumps. We provide here a comprehensive overview of the structural and functional aspects of catalytically asymmetric ABC pumps with an emphasis on the PDR subfamily. Furthermore, given the increasing evidence of efflux-mediated antifungal resistance in clinical settings, we also discuss potential grounds to explore PDR transporters as therapeutic targets.


Asunto(s)
Transportadoras de Casetes de Unión a ATP , Proteínas de Transporte de Membrana , Humanos , Transportadoras de Casetes de Unión a ATP/genética , Transportadoras de Casetes de Unión a ATP/metabolismo , Saccharomyces cerevisiae , Farmacorresistencia Fúngica , Adenosina Trifosfato/metabolismo
9.
Molecules ; 28(9)2023 May 08.
Artículo en Inglés | MEDLINE | ID: mdl-37175358

RESUMEN

As a natural polyphenolic compound, chlorogenic acid (CGA) has attracted increasing attention for its various biological activities, such as antioxidant, liver protection, intestinal barrier protection, and effective treatment of obesity and type II diabetes. However, the poor solubility of CGA in hydrophobic media limits its application in the food, drug and cosmetic industries. In order to obtain new hydrophobic derivatives, a highly efficient synthesis approach of CGA oleyl alcohol ester (CGOA) under non-catalytic and solvent-free conditions was developed in this study. The influences of reaction temperature, reaction time, substrate molar ratio, and stirring rate on the CGA conversion were investigated. The results showed that the optimal conditions were as follows: reaction temperature 200 °C, reaction time 3 h, molar ratio of CGA to oleyl alcohol 1:20, and stirring rate 200 rpm. Under these conditions, the CGA conversion could reach 93.59%. Then, the obtained crude product was purified by solvent extraction and column chromatography, and the purify of CGOA was improved to 98.72%. Finally, the structure of CGOA was identified by FT-IR, HPLC-MS and NMR. This study provides a simple and efficient strategy for the preparation of CGOA with the avoidance of catalysts and solvents.


Asunto(s)
Diabetes Mellitus Tipo 2 , Ésteres , Humanos , Solventes/química , Ácido Clorogénico/química , Espectroscopía Infrarroja por Transformada de Fourier
10.
Sci Total Environ ; 866: 161453, 2023 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-36626987

RESUMEN

Thermal plasma activation of CH4-CO2 reforming (CRM) to syngas under non-catalytic conditions is an efficient and clean technology for the large-scale utilization of hydrocarbon resources and the conversion of greenhouse gases. This study investigates the equilibrium state and transformation mechanism of a CRM reaction system activated by thermal plasma through experimental, thermodynamic, and kinetic analyses. The experimental results illustrated that the CO2 conversion rate and H2 selectivity showed a downward trend with an increase in the CO2/CH4 molar ratio, whereas the CH4 conversion rate and CO selectivity showed the opposite trend. When CO2/CH4 molar ratio was 6/4, the selectivity for CO and H2 increased to 87.0 % and 80.8 %, respectively. Excess CO2 promotes the partial oxidation of CH4 to eliminate carbon deposition, resulting in an H2/CO molar ratio value closer to 1. Thermodynamic results show that the thermal-plasma-initiated CRM reaction can reach thermodynamic equilibrium more easily than the conventional catalyzed reactions, achieving much higher feedstock gas conversion without carbon deposition. The kinetic results obtained from the PSR model revealed that CH4 and CO2 were cleaved to form free radicals at the instant of contact with the plasma flame. O, H, and other particles generated in the form of free radicals rapidly collided with each other and transformed into CO and H2, accelerating the reaction process. The results presented in this study will help reveal the transformation mechanism of the CRM reaction activated by thermal plasma under non-catalytic conditions and provide a new perspective for studying CRM reactions.

11.
Waste Manag Res ; 41(1): 195-204, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-35913072

RESUMEN

Incineration is the most effective method for reducing the increasing waste volume. However, as the pollutants generated during incineration may cause secondary pollution, blocking them in advance is necessary. During incineration, prevention facilities are operated to reduce the amount of pollutants. Conventional selective non-catalytic reduction (SNCR) reduces nitrogen oxides (NOx) by injecting ammonia and urea as reducing agents. In this study, the NOx reduction effect on food wastewater (FW) was examined. In addition, the removal efficiency was compared at different concentrations of urea mixed with FW. When different concentrations of urea were injected in SNCR facilities A, B and C, NOx removal efficiencies of up to 75% were observed; with FW injection only, removal efficiency was 56%; and when both urea and FW were injected, removal efficiency was up to 79%. Although FW showed a lower NOx removal efficiency than urea, injecting both increased the efficiency. In addition, when air pollutant emissions and the incinerator temperature were analysed, we found that they could be managed without exceeding the allowed limits. However, for the injection and incineration of reducing agents, the characteristics of the incineration facility and reducing agents must be considered.


Asunto(s)
Contaminantes Atmosféricos , Contaminantes Ambientales , Incineración , Aguas Residuales , Sustancias Reductoras , Urea
12.
Bioresour Technol ; 367: 128276, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36347476

RESUMEN

The pre-adsorption of non-catalytic/blocking proteins onto the lignin component of pretreated biomass has been shown to significantly increase the effectiveness of subsequent enzyme-mediated hydrolysis of the cellulose by limiting non-productive enzyme adsorption. Layer-by-layer adsorption of non-catalytic proteins and enzymes onto lignin was monitored using Quartz Crystal Micro balancing combined with Dissipation monitoring (QCM-D) and conventional protein adsorption. These methods were used to assess the interaction between soft/hardwood lignins, cellulases and the three non-catalytic proteins BSA, lysozyme and ovalbumin. The QCM-D analysis showed higher adsorption rates for all of the non-catalytic proteins onto the lignin films as compared to cellulases. This suggested that the "blocking" proteins would preferentially adsorb to the lignin rather than the enzymes. Pre-incubation of the lignin films with blocking proteins resulted in reduced adsorption of cellulases onto the lignin, significantly enhancing cellulose hydrolysis.


Asunto(s)
Celulasa , Celulasas , Lignina/química , Celulasa/metabolismo , Hidrólisis , Celulosa/química , Adsorción , Celulasas/metabolismo , Proteínas
13.
Nan Fang Yi Ke Da Xue Xue Bao ; 42(11): 1594-1603, 2022 Nov 20.
Artículo en Chino | MEDLINE | ID: mdl-36504051

RESUMEN

OBJECTIVE: To observe the effects of Casitas B lymphoma (CBL) protein on proliferation, migration and invasion of breast cancer cells and explore its mechanism of action. METHODS: Cultured breast cancer cell lines MDA-MB-231 and MCF7A were transfected with a CBL-overexpressing plasmid and a specific siRNA targeting CBL (siRNA-CBL), respectively, and the changes in cell proliferation, migration and invasion were examined using colony-forming assay, cell counting kit-8 (CCK-8), scratch test and Transwell assay. Flow cytometry and Western blotting were performed to examine the effects of CBL overexpression on cell cycle and epithelial-mesenchymal transition (EMT) of MDA-MB-231 cells, and the changes in the number of filamentous pseudopodia were observed by rhodamine- labeled phalloidin staining of the cytoskeleton. IP-mass spectrometry identified NCK2 as the interacting proteins of CBL, and their interaction was verified by immunoprecipitation and immunofluorescence co-localization experiments in HEK-293T cells transfected with the plasmids for overexpression of CBL, NCK2, or both. Cycloheximide tracking and ubiquitination assays were used for assessing the effects of CBL on stability and ubiquitination of NCK2 protein in MDA-MB-231 cells; CCK-8 and Transwell assays were used to determine the effect of NCK2 overexpression on CBL-mediated proliferation and migration of the cells. RESULTS: The proliferation, migration and invasion were significantly suppressed in MDA-MB-231 cells overexpressing CBL (P < 0.05) and significantly enhanced in MCF7 cells with CBL silencing (P < 0.01). Silencing of CBL promoted G1/S transition in MCF7 cells (P < 0.05). Overexpression of CBL significantly decreased the expressions of CDK2/4 (P < 0.01), cyclinA2/B1/D1/D3/E2 (P < 0.05), Snail, N-cadherin, claudin-1 (P < 0.05), and upregulated the expression of E-cadherin (P < 0.05). CBL silencing upregulated the expressions of CDK2/4/6 (P < 0.05), cyclin A2/B1/D1/D3/E2 (P < 0.05), Snail, vimentin, and claudin-1 (P < 0.05) and down-regulated E-cadherin expression (P < 0.05). CBL overexpression obviously reduced the number of filamentous pseudopodia in MDA-MB-231 cells, and the reverse changes were observed in MCF7 cells with CBL silencing. In MDA-MB-231 cells, CBL overexpression lowered NCK2 protein stability (P < 0.05) and promoted its ubiquitin-mediated degradation (P < 0.01). Overexpression of NCK2 obviously reversed CBL-mediated inhibition of cell proliferation and migration (P < 0.01). CONCLUSION: CBL can inhibit the proliferation, migration and invasion of breast cancer cells through ubiquitination-mediated degradation of NCK2.


Asunto(s)
Linfoma , Humanos , Citoesqueleto , Cadherinas , Células MCF-7 , Proteínas Oncogénicas , Proteínas Adaptadoras Transductoras de Señales
14.
Molecules ; 27(23)2022 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-36500273

RESUMEN

Lignocellulosic biomass (LCB) has remained a latent alternative resource to be the main substitute for oil and its derivatives in a biorefinery concept. However, its complex structure and the underdeveloped technologies for its large-scale processing keep it in a state of constant study trying to establish a consolidated process. In intensive processes, enzymes have been shown to be important molecules for the fractionation and conversion of LCB into biofuels and high-value-added molecules. However, operational challenges must be overcome before enzyme technology can be the main resource for obtaining second-generation sugars. The use of additives is shown to be a suitable strategy to improve the saccharification process. This review describes the mechanisms, roles, and effects of using additives, such as surfactants, biosurfactants, and non-catalytic proteins, separately and integrated into the enzymatic hydrolysis process of lignocellulosic biomass. In doing so, it provides a technical background in which operational biomass processing hurdles such as solids and enzymatic loadings, pretreatment burdens, and the unproductive adsorption phenomenon can be addressed.


Asunto(s)
Lignina , Tensoactivos , Lignina/química , Fermentación , Biomasa , Hidrólisis , Biocombustibles
15.
Molecules ; 27(19)2022 Sep 24.
Artículo en Inglés | MEDLINE | ID: mdl-36234848

RESUMEN

Lysozymes are hydrolytic enzymes characterized by their ability to cleave the ß-(1,4)-glycosidic bonds in peptidoglycan, a major structural component of the bacterial cell wall. This hydrolysis action compromises the integrity of the cell wall, causing the lysis of bacteria. For more than 80 years, its role of antibacterial defense in animals has been renowned, and it is also used as a preservative in foods and pharmaceuticals. In order to improve the antimicrobial efficacy of lysozyme, extensive research has been intended for its modifications. This manuscript reviews the natural antibiotic compound lysozyme with reference to its catalytic and non-catalytic mode of antibacterial action, lysozyme types, susceptibility and resistance of bacteria, modification of lysozyme molecules, and its applications in the food industry.


Asunto(s)
Antiinfecciosos , Muramidasa , Animales , Antibacterianos/farmacología , Antivirales , Bacterias/metabolismo , Industria de Alimentos , Muramidasa/química , Peptidoglicano/metabolismo , Preparaciones Farmacéuticas
16.
Comput Struct Biotechnol J ; 20: 3140-3150, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35782739

RESUMEN

Both ß-mannanases and ß-mannosidases are required for mannan-backbone degradation into mannose. In this study, two ß-mannosidases of glycoside hydrolase (GH) families 2 (BtMan2A) and 5 (CmMan5A) were evaluated for their substrate specificities and galactomannan binding ability. BtMan2A preferred short manno-oligomers, while CmMan5A preferred longer ones; DP >2, and galactomannans. BtMan2A displayed irreversible galactomannan binding, which was pH-dependent, with higher binding observed at low pH, while CmMan5A had limited binding. Docking and molecular dynamics (MD) simulations showed that BtMan2A galactomannan binding was stronger under acidic conditions (-8.4 kcal/mol) than in a neutral environment (-7.6 kcal/mol), and the galactomannan ligand was more unstable under neutral conditions than acidic conditions. Qualitative surface plasmon resonance (SPR) experimentally confirmed the reduced binding capacity of BtMan2A at pH 7. Finally, synergistic ß-mannanase to ß-mannosidase (BtMan2A or CmMan5A) ratios required for maximal galactomannan hydrolysis were determined. All CcManA to CmMan5A combinations were synergistic (≈1.2-fold), while combinations of CcManA with BtMan2A (≈1.0-fold) yielded no hydrolysis improvement. In conclusion, the low specific activity of BtMan2A towards long and galactose-containing oligomers and its non-catalytic galactomannan binding ability led to no synergy with the mannanase, making GH2 mannosidases ineffective for use in cocktails for mannan degradation.

17.
Epigenomics ; 14(10): 629-643, 2022 05.
Artículo en Inglés | MEDLINE | ID: mdl-35410490

RESUMEN

DNMT1 is the main enzyme that uses the information on DNA methylation patterns in the parent strand and methylates the daughter strand in freshly replicated hemimethylated DNA. It is widely known that DNMT1 is a component of the epigenetic machinery mediating gene repression via increased promoter methylation. However, recent data suggest that DNMT1 can also modulate gene expression independent of its catalytic activity and participates in multiple processes including the cell cycle, DNA damage repair and stem cell function. This review summarizes the noncanonical functions of DNMT1, some of which are clearly independent of maintenance methylation. Finally, phenotypic data on altered DNMT1 levels suggesting that maintenance of optimal levels of DNMT1 is vital for normal development and health is presented.


Asunto(s)
Fenómenos Biológicos , ADN (Citosina-5-)-Metiltransferasas , ADN/metabolismo , ADN (Citosina-5-)-Metiltransferasa 1/genética , ADN (Citosina-5-)-Metiltransferasa 1/metabolismo , ADN (Citosina-5-)-Metiltransferasas/genética , ADN (Citosina-5-)-Metiltransferasas/metabolismo , Metilación de ADN , Humanos , Regiones Promotoras Genéticas
18.
Plant J ; 111(1): 117-133, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35437852

RESUMEN

Serine carboxypeptidase-like acyltransferases (SCPL-ATs) play a vital role in the diversification of plant metabolites. Galloylated flavan-3-ols highly accumulate in tea (Camellia sinensis), grape (Vitis vinifera), and persimmon (Diospyros kaki). To date, the biosynthetic mechanism of these compounds remains unknown. Herein, we report that two SCPL-AT paralogs are involved in galloylation of flavan-3-ols: CsSCPL4, which contains the conserved catalytic triad S-D-H, and CsSCPL5, which has the alternative triad T-D-Y. Integrated data from transgenic plants, recombinant enzymes, and gene mutations showed that CsSCPL4 is a catalytic acyltransferase, while CsSCPL5 is a non-catalytic companion paralog (NCCP). Co-expression of CsSCPL4 and CsSCPL5 is likely responsible for the galloylation. Furthermore, pull-down and co-immunoprecipitation assays showed that CsSCPL4 and CsSCPL5 interact, increasing protein stability and promoting post-translational processing. Moreover, phylogenetic analyses revealed that their homologs co-exist in galloylated flavan-3-ol- or hydrolyzable tannin-rich plant species. Enzymatic assays further revealed the necessity of co-expression of those homologs for acyltransferase activity. Evolution analysis revealed that the mutations of the CsSCPL5 catalytic residues may have taken place about 10 million years ago. These findings show that the co-expression of SCPL-ATs and their NCCPs contributes to the acylation of flavan-3-ols in the plant kingdom.


Asunto(s)
Diospyros , Vitis , Acilación , Aciltransferasas/metabolismo , Carboxipeptidasas/genética , Carboxipeptidasas/metabolismo , Flavonoides , Filogenia , Plantas/metabolismo , Polifenoles , Vitis/metabolismo
19.
Cell Chem Biol ; 29(5): 785-798.e19, 2022 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-35364007

RESUMEN

Viruses are responsible for some of the most deadly human diseases, yet available vaccines and antivirals address only a fraction of the potential viral human pathogens. Here, we provide a methodology for managing human herpesvirus (HHV) infection by covalently inactivating the HHV maturational protease via a conserved, non-catalytic cysteine (C161). Using human cytomegalovirus protease (HCMV Pr) as a model, we screened a library of disulfides to identify molecules that tether to C161 and inhibit proteolysis, then elaborated hits into irreversible HCMV Pr inhibitors that exhibit broad-spectrum inhibition of other HHV Pr homologs. We further developed an optimized tool compound targeted toward HCMV Pr and used an integrative structural biology and biochemical approach to demonstrate inhibitor stabilization of HCMV Pr homodimerization, exploiting a conformational equilibrium to block proteolysis. Irreversible HCMV Pr inhibition disrupts HCMV infectivity in cells, providing proof of principle for targeting proteolysis via a non-catalytic cysteine to manage viral infection.


Asunto(s)
Infecciones por Citomegalovirus , Citomegalovirus , Cisteína , Citomegalovirus/fisiología , Humanos , Péptido Hidrolasas , Proteasas Virales
20.
Nanotechnology ; 33(15)2022 Jan 19.
Artículo en Inglés | MEDLINE | ID: mdl-34969026

RESUMEN

Overlayer growth of graphene on an epitaxial graphene/silicon carbide (SiC) as a solid template by ethanol chemical vapor deposition is performed over a wide growth temperature range from 900 °C to 1450 °C. Structural analysis using atomic force and scanning tunneling microscopies reveal that graphene islands grown at 1300 °C form hexagonal twisted bilayer graphene as a single crystal. When the growth temperature exceeds 1400 °C, the grown graphene islands show a circular shape. Moreover, moiré patterns with different periods are observed in a single graphene island. This means that the graphene islands grown at high temperature are composed of several graphene domains with different twist angles. From these results, we conclude that graphene overlayer growth on the epitaxial graphene/SiC solid at 1300 °C effectively synthesizes the twisted few-layer graphene with a high crystallinity.

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