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PURPOSE: Finasteride and dutasteride are used to treat benign prostatic hyperplasia (BPH) and reduce the risk of developing prostate cancer. Finasteride blocks only the type 2 form of 5-alpha-reductase, whereas dutasteride blocks both type 1 and 2 forms of the enzyme. Previous studies suggest the possibility that dutasteride may be superior to finasteride in preventing prostate cancer. We directly compared the effects of finasteride and dutasteride on the risk of prostate cancer in patients with BPH using a pooled analysis of 15 real-world databases. MATERIALS AND METHODS: We conducted a multicenter, cohort study of new-users of finasteride and dutasteride. We include patients who were prescribed 5 mg finasteride or dutasteride for the first time to treat BPH and had at least 180 days of prescription. We excluded patients with a history of prostate cancer or a prostate-specific antigen level ≥ 4 ng/mL before the study drug prescription. Cox regression analysis was performed to examine the hazard ratio (HR) for prostate cancer after propensity score (PS) matching. RESULTS: A total of 8,284 patients of new-users of finasteride and 8,670 patients of new-users of dutasteride were included across the 15 databases. In the overall population, compared to dutasteride, finasteride was associated with a lower risk of prostate cancer in both on-treatment and intent-to-treat time-at-risk periods. After 1:1 PS matching, 4,897 patients using finasteride and 4,897 patients using dutasteride were enrolled in the present study. No significant differences were observed for risk of prostate cancer between finasteride and dutasteride both on-treatment (HR=0.66, 95% confidence interval [CI]: 0.44-1.00; p=0.051) and intent-to-treat time-at-risk periods (HR=0.87, 95% CI: 0.67-1.14; p=0.310). CONCLUSIONS: Using real-world databases, the present study demonstrated that dutasteride was not associated with a lower risk of prostate cancer than finasteride in patients with BPH.
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BACKGROUND: The efficacy and safety of each third-generation drug-eluting stent with ultrathin struts and advanced polymer technology remain unclear. We investigated the clinical outcomes of percutaneous coronary intervention using the Coroflex ISAR polymer-free sirolimus-eluting stent (SES) or Orsiro biodegradable polymer SES. METHODS: The HOST-IDEA trial (Harmonizing Optimal Strategy for Treatment of Coronary Artery Stenosis-Coronary Intervention With Next-Generation Drug-Eluting Stent Platforms and Abbreviated Dual Antiplatelet Therapy), initially designed with a 2×2 factorial approach, sought to randomize patients undergoing percutaneous coronary intervention based on dual antiplatelet therapy duration (3 versus 12 months) and stent type (Coroflex ISAR versus Orsiro). Despite randomizing 2013 patients for dual antiplatelet therapy duration, the stent arm transitioned to a registry format during the trial. Among these, 328 individuals (16.3%) were randomized for Coroflex ISAR or Orsiro SES, while 1685 (83.7%) underwent percutaneous coronary intervention without stent-type randomization. In this study, the Coroflex ISAR (n=559) and Orsiro groups (n=1449) were matched using a propensity score. The prespecified primary end point was target lesion failure, a composite of cardiac death, target vessel myocardial infarction, and clinically driven target lesion revascularization at 12 months. RESULTS: The baseline patient and procedural characteristics were well balanced between the Coroflex ISAR and Orsiro groups after propensity score matching (n=559, each group). The Coroflex ISAR group was significantly associated with a higher rate of target lesion failure, mainly driven by clinically driven target lesion revascularization, compared with the Orsiro group (3.4% versus 1.1%; hazard ratio, 3.21 [95% CI, 1.28-8.05]; P=0.01). A higher risk of target lesion failure in the Coroflex ISAR group was consistently observed across various subgroups. The rates of any bleeding (hazard ratio, 0.85 [95% CI, 0.51-1.40]; P=0.52) and major bleeding (hazard ratio, 1.58 [95% CI, 0.61-4.08]; P=0.34) were comparable between the 2 groups. CONCLUSIONS: In this propensity score-matched analysis of the stent arm registry from the HOST-IDEA trial, the Orsiro SES was associated with significantly better outcomes in terms of 1-year target lesion failure, mainly driven by clinically driven target lesion revascularization, than the Coroflex ISAR SES. REGISTRATION: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02601157.
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Implantes Absorbibles , Fármacos Cardiovasculares , Enfermedad de la Arteria Coronaria , Stents Liberadores de Fármacos , Intervención Coronaria Percutánea , Inhibidores de Agregación Plaquetaria , Polímeros , Diseño de Prótesis , Sistema de Registros , Sirolimus , Humanos , Masculino , Femenino , Intervención Coronaria Percutánea/instrumentación , Intervención Coronaria Percutánea/efectos adversos , Intervención Coronaria Percutánea/mortalidad , Anciano , Persona de Mediana Edad , Resultado del Tratamiento , Factores de Tiempo , Polímeros/química , Enfermedad de la Arteria Coronaria/terapia , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/mortalidad , Factores de Riesgo , Inhibidores de Agregación Plaquetaria/administración & dosificación , Inhibidores de Agregación Plaquetaria/efectos adversos , Sirolimus/administración & dosificación , Sirolimus/efectos adversos , Fármacos Cardiovasculares/administración & dosificación , Fármacos Cardiovasculares/efectos adversos , Terapia Antiplaquetaria Doble , Hemorragia/inducido químicamente , Medición de Riesgo , Estenosis Coronaria/terapia , Estenosis Coronaria/diagnóstico por imagen , Estenosis Coronaria/mortalidad , Estudios Prospectivos , Infarto del Miocardio/etiologíaRESUMEN
OBJECTIVE: Predicting which young people are likely to use tobacco in the future is critical for prevention and intervention. Although measures for assessing susceptibility to using tobacco have fulfilled this goal for decades, there is almost no standard for the number of items that should be administered, or which items should be administered for which products. This study explored whether brief but psychometrically sound versions of commonly used susceptibility measures can adequately capture the construct relative to longer measures. METHOD: A sample of young people (N = 451; Mage = 16.5 years; 64% females; 65% White) completed 33 susceptibility items, which are designed to assess susceptibility to use different types of tobacco products (cigarette, smokeless tobacco, vaping products, and little cigars/cigarillos) of various flavors (tobacco, menthol, and sweet). RESULTS: Analysis of these 33 items indicated that asking about the likelihood of using each tobacco product class when a best friend offers it (four items in all) captures 98.5% of information that is captured using the longer set of items; asking the best friend question for each product by each flavor category (11 items in all) captures 99.7% of the information. CONCLUSIONS: Depending on research needs, tobacco use susceptibility can be measured with little loss of information by administering a limited set of items assessing the likelihood that a young person will use a tobacco product if a friend offers it for any product-flavor combination. (PsycInfo Database Record (c) 2024 APA, all rights reserved).
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Tyrosinase-mediated protein conjugation has recently drawn attention as a site-specific protein modification tool under mild conditions. However, the tyrosinases reported to date act only on extremely exposed tyrosine residues, which limits where the target tyrosine can be located. Herein, we report a tyrosinase from Streptomyces avermitilis (SaTYR), that exhibits a much higher activity against tyrosine residues on the protein surface than other tyrosinases. We determined the crystal structure of SaTYR and revealed that the enzyme has a relatively flat and shallow substrate-binding pocket to accommodate a protein substrate. We demonstrated SaTYR-mediated fluorescence dye tagging and PEGylation of a surface tyrosine residue that was unreacted by other tyrosinases with an approximately 95.2 % conjugation yield in 1 h. We also present a structural rationale that considers the steric hindrance from adjacent residues and surrounding structures along with the extent of solvent exposure of residues, as necessary when determining the optimal positions for introducing target tyrosine residues in SaTYR-mediated protein modification. The study demonstrated that the novel tyrosinase, SaTYR, extends the scope of tyrosinase-mediated protein modification, and we propose that site-specific tyrosine conjugation using SaTYR is a promising strategy for protein bioconjugation in various applications.
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Monofenol Monooxigenasa , Streptomyces , Monofenol Monooxigenasa/metabolismo , Proteínas/metabolismo , Tirosina/químicaRESUMEN
Corynebacterium glutamicum is an industrial workhorse applied in the production of valuable biochemicals. In the process of bio-based chemical production, improving cofactor recycling and mitigating cofactor imbalance are considered major solutions for enhancing the production yield and efficiency. Although, glyceraldehyde-3-phosphate dehydrogenase (GapDH), a glycolytic enzyme, can be a promising candidate for a sufficient NADPH cofactor supply, however, most microorganisms have only NAD-dependent GapDHs. In this study, we performed functional characterization and structure determination of novel NADPH-producing GapDH from C. glutamicum (CgGapX). Based on the crystal structure of CgGapX in complex with NADP cofactor, the unique structural features of CgGapX for NADP stabilization were elucidated. Also, N-terminal additional region (Auxiliary domain, AD) appears to have an effect on enzyme stabilization. In addition, through structure-guided enzyme engineering, we developed a CgGapX variant that exhibited 4.3-fold higher kcat, and 1.2-fold higher kcat/KM values when compared with wild-type. Furthermore, a bioinformatic analysis of 100 GapX-like enzymes from 97 microorganisms in the KEGG database revealed that the GapX-like enzymes possess a variety of AD, which seem to determine enzyme stability. Our findings are expected to provide valuable information for supplying NADPH cofactor pools in bio-based value-added chemical production.
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Corynebacterium glutamicum , NADP/metabolismo , Gliceraldehído-3-Fosfato Deshidrogenasas/genética , Gliceraldehído-3-Fosfato Deshidrogenasas/metabolismo , GlucólisisRESUMEN
Dehydroquinate dehydratase (DHQD) catalyzes the conversion of 3-dehydroquinic acid (DHQ) into 3-dehydroshikimic acid in the mid stage of the shikimate pathway, which is essential for the biosynthesis of aromatic amino acids and folates. Here, we report two the crystal structures of type II DHQD (CgDHQD) derived from Corynebacterium glutamicum, which is a widely used industrial platform organism. We determined the structures for CgDHQDWT with the citrate at a resolution of 1.80Å and CgDHQDR19A with DHQ complexed forms at a resolution of 2.00 Å, respectively. The enzyme forms a homododecamer consisting of four trimers with three interfacial active sites. We identified the DHQ-binding site of CgDHQD and observed an unusual binding mode of citrate inhibitor in the site with a half-opened lid loop. A structural comparison of CgDHQD with a homolog derived from Streptomyces coelicolor revealed differences in the terminal regions, lid loop, and active site. Particularly, CgDHQD, including some Corynebacterium species, possesses a distinctive residue P105, which is not conserved in other DHQDs at the position near the 5-hydroxyl group of DHQ. Replacements of P105 with isoleucine and valine, conserved in other DHQDs, caused an approximately 70% decrease in the activity, but replacement of S103 with threonine (CgDHQDS103T) caused a 10% increase in the activity. Our biochemical studies revealed the importance of key residues and enzyme kinetics for wild type and CgDHQDS103T, explaining the effect of the variation. This structural and biochemical study provides valuable information for understanding the reaction efficiency that varies due to structural differences caused by the unique sequences of CgDHQD.
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Corynebacterium glutamicum , Corynebacterium glutamicum/genética , Corynebacterium glutamicum/metabolismo , Hidroliasas/genética , Hidroliasas/química , Hidroliasas/metabolismo , Sitios de Unión , CitratosRESUMEN
Since the discovery of l-glutamate-producing Corynebacterium glutamicum, it has evolved to be an industrial workhorse. For biobased chemical production, suppling sufficient amounts of the NADPH cofactor is crucial. Glyceraldehyde-3-phosphate dehydrogenase (GAPDH), a glycolytic enzyme that converts glyceraldehyde-3-phosphate (G3P) to 1,3-bisphosphoglycerate and produces NADH, is a major prospective solution for the cofactor imbalance issue. In this study, we determined the crystal structure of GAPDH from C. glutamicum ATCC13032 (CgGAPDH). Based on the structural information, we generated six CgGAPDH variants, CgGAPDHL36S, CgGAPDHL36S/T37K, CgGAPDHL36S/T37K/P192S, CgGAPDHL36S/T37K/F100V/P192S, CgGAPDHL36S/T37K/F100L/P192S, and CgGAPDHL36S/T37K/F100I/P192S, that can produce both NADH and NAPDH. The final CgGAPDHL36S/T37K/F100V/P192S variant showed a 212-fold increase in enzyme activity for NADP as well as 200% and 30% increased activity for the G3P substrate under NAD and NADP cofactor conditions, respectively. In addition, crystal structures of CgGAPDH variants in complex with NAD(P) permit the elucidation of differences between wild-type CgGAPDH and variants in relation to cofactor stabilization.
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Corynebacterium glutamicum , NAD , NADP/metabolismo , NAD/metabolismo , Corynebacterium glutamicum/metabolismo , Estudios Prospectivos , Gliceraldehído-3-Fosfato Deshidrogenasas/genética , Gliceraldehído-3-Fosfato Deshidrogenasas/metabolismo , Ingeniería de ProteínasRESUMEN
BACKGROUND AND AIMS: Whether the effect of a combination strategy rather than increasing doses of one drug to lower low-density lipoprotein cholesterol (LDL-C) levels is consistent across baseline LDL-C levels remains uncertain. METHODS: In the RACING trial, which showed a non-inferiority of moderate-intensity statin with ezetimibe (rosuvastatin 10 mg with ezetimibe 10 mg) to high-intensity statin (rosuvastatin 20 mg) for the primary outcome (3-year composite of cardiovascular death, major cardiovascular event, or stroke), the heterogeneity in treatment effect according to baseline LDL-C levels was assessed for the primary and secondary outcomes (clinical efficacy and safety). RESULTS: Of 3780 participants, 2817 participants (74.5%) had LDL-C <100 mg/dL, and 963 participants (25.5%) had LDL-C ≥100 mg/dL. The treatment effect of combination therapy versus high-intensity statin monotherapy was similar among the lower LDL-C subset (8.8% vs. 10.2%; hazard ratio [HR] 0.85, 95% confidence interval [CI] 0.67 to 1.08, p = 0.19) and the higher LDL-C subset (10.8% vs. 9.6 %; HR 1.14, 95% CI 0.76 to 1.7, p = 0.53) without a significant interaction (interaction p = 0.22). Of the secondary outcomes, the 1-, 2-, and 3-year achievement of LDL-C <70 mg/dL was greater in the combination therapy group regardless of baseline LDL-C levels. CONCLUSIONS: Among ASCVD patients, there was no heterogeneity in the effect of moderate-intensity statin plus ezetimibe combination therapy in the higher and lower baseline LDL-C levels for the 3-year composite of cardiovascular outcomes.
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Anticolesterolemiantes , Aterosclerosis , Enfermedades Cardiovasculares , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/efectos adversos , Ezetimiba/uso terapéutico , Rosuvastatina Cálcica/efectos adversos , LDL-Colesterol , Anticolesterolemiantes/efectos adversos , Enfermedades Cardiovasculares/tratamiento farmacológico , Enfermedades Cardiovasculares/prevención & control , Aterosclerosis/tratamiento farmacológico , Resultado del Tratamiento , Quimioterapia CombinadaRESUMEN
Global longitudinal strain (GLS) is a valuable indicator of subclinical myocardial dysfunction. Whether the effect of aging on subclinical left ventricular dysfunction is sex-specific is not well documented. This study aimed to identify age-related changes in GLS according to sex in patients with a normal left ventricular ejection fraction (LVEF). In this cross-sectional, single-center cohort study in Korea, participants who underwent GLS measurement using 2D speckle-tracking echocardiography were retrospectively reviewed, and participants with normal LVEF (≥ 55%) without documented cardiovascular disease were included. Reduced GLS was defined as absolute values below 18%. Of 682 study participants (mean age, 58; female, 51.5%), 209 (30.6%) had reduced GLS. Females with reduced GLS were older than those with normal GLS (68 vs. 58 years, P < 0.001); with no difference of age in males (55 vs. 57 years; P = 0.265). Univariate analysis showed age to correlate significantly with reduced GLS only in female (r = - 0.364; P < 0.001). In multivariable analysis, female > 66 years old had significantly higher risk of reduced GLS (Odds ratio 2.66; 95% CI 1.22-5.76; P = 0.014). In participants with normal LVEF, GLS decreased with age in females but not in males. Particularly, females aged 66 years and older had a significantly higher risk of reduced GLS. These findings suggest that GLS could be a valuable parameter for assessing subclinical cardiac dysfunction, especially in older females.
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Disfunción Ventricular Izquierda , Función Ventricular Izquierda , Humanos , Masculino , Femenino , Anciano , Persona de Mediana Edad , Ventrículos Cardíacos/diagnóstico por imagen , Volumen Sistólico , Estudios de Cohortes , Estudios Retrospectivos , Estudios Transversales , Caracteres Sexuales , Tensión Longitudinal Global , Disfunción Ventricular Izquierda/diagnóstico por imagenRESUMEN
S-Adenosylmethionine (SAM) acts as a methyl donor in living organisms, and S-adenosylmethionine synthetase (MetK) is an essential enzyme for cells, as it synthesizes SAM from methionine and adenosine triphosphate (ATP). This study determined the crystal structures of the apo form and adenosine/triphosphate complex form of MetK from Corynebacterium glutamicum (CgMetK). Results showed that CgMetK has an allosteric inhibitor binding site for the SAM product in the vicinity of the active site and is inhibited by SAM both competitively and noncompetitively. Through structure-guided protein engineering, the CgMetKE68A variant was developed that exhibited an almost complete release of inhibition by SAM with rather enhanced enzyme activity. The crystal structure of the CgMetKE68A variant revealed that the formation of a new hydrogen bond between Tyr66 and Glu102 by the E68A mutation disrupted the allosteric SAM binding site and also improved the protein thermal stability by strengthening the tetramerization of the enzyme.
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Corynebacterium glutamicum , Metionina Adenosiltransferasa , Metionina Adenosiltransferasa/genética , Metionina Adenosiltransferasa/química , Metionina Adenosiltransferasa/metabolismo , Corynebacterium glutamicum/genética , Corynebacterium glutamicum/metabolismo , Metionina/metabolismo , S-Adenosilmetionina/metabolismo , Adenosina Trifosfato/metabolismoRESUMEN
BACKGROUND AND OBJECTIVES: Myocarditis is a potentially fatal disease, but curative treatments have not yet been established. Myocardial inflammation is an important pathogenesis of this disease, and immunosuppressants such as methylprednisolone and immunoglobulin have been used for treatment; however, the effectiveness needs to be improved. Thalidomide and dipeptidyl peptidase (DPP) 4 inhibitors were recently investigated regarding their immunomodulatory properties. This study aimed to test whether thalidomide or a DPP4 inhibitor (evogliptin) can improve the effectiveness of myocarditis treatment using a rat model of experimental autoimmune myocarditis (EAM). METHODS: Rats with or without myocarditis were administered thalidomide at 100 mg/kg/day and DPP4 inhibitor at 10 mg/kg/day orally. Measurement of echocardiography, serum inflammatory cytokines, myocardial histopathological examination, and immunohistochemical staining for leukocytes, macrophages, CD4+ T cells, and cytoskeleton were performed after 3 weeks, and the fibrosis area was measured after 3 and 6 weeks. RESULTS: Thalidomide and DPP4 inhibitor did not reduce the severity of myocarditis compared with the EAM without treatment rats by comparing the echocardiographic data, myocardial CD4+, macrophages, neutrophil infiltrations, and the heart weight/body weight ratio in 3 weeks. The levels of inflammatory cytokines were not lower in the thalidomide and DPP4 inhibitor-treated group than in the untreated group in 3 weeks. In 6 weeks, thalidomide and DPP4 inhibitors did not reduce the fibrosis area compared to untreated groups. CONCLUSIONS: Although thalidomide and the DPP4 inhibitor had an immunomodulatory effect and are used against inflammatory diseases, they did not ameliorate myocardial inflammation and fibrosis in this rat model of EAM.
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The mesophilic PETase from Ideonella sakaiensis (IsPETase) has been shown to exhibit high PET hydrolysis activity, but its low stability limits its industrial applications. Here, we developed a variant, Z1-PETase, with enhanced soluble protein yield and durability while maintaining or improving activity at lower temperatures. The selected Z1-PETase not only exhibited a 20-fold improvement in soluble protein yield compared to the previously engineered IsPETaseS121E/D186H/S242T/N246D (4p) variant, but also demonstrated a 30% increase in low-temperature activity at 40 °C, along with an 11 °C increase in its TmD value. The PET depolymerization test across a temperature range low to high (30-70 °C) confirmed that Z1-PETase exhibits high accessibility of mesophilic PET hydrolase and rapid depolymerizing rate at higher temperature in accordance with the thermal behaviors of polymer and enzyme. Additionally, structural interpretation indicated that the stabilization of specific active site loops in Z1-PETase contributes to enhanced thermostability without adversely impacting enzymatic activity. In a pH-stat bioreactor, Z1-PETase depolymerized > 90% of both transparent and colored post-consumer PET powders within 24 and 8 h at 40 °C and 55 °C, respectively, demonstrating that the utility of this IsPETase variant in the bio-recycling of PET.
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Reactores Biológicos , Hidrolasas , Hidrólisis , Polímeros , PolvosRESUMEN
Excessive polyethylene terephthalate (PET) waste causes a variety of problems. Extensive research focused on the development of superior PET hydrolases for PET biorecycling has been conducted. However, template enzymes employed in enzyme engineering mainly focused on IsPETase and leaf-branch compost cutinase, which exhibit mesophilic and thermophilic hydrolytic properties, respectively. Herein, we report a PET hydrolase from Cryptosporangium aurantiacum (CaPETase) that exhibits high thermostability and remarkable PET degradation activity at ambient temperatures. We uncover the crystal structure of CaPETase, which displays a distinct backbone conformation at the active site and residues forming the substrate binding cleft, compared with other PET hydrolases. We further develop a CaPETaseM9 variant that exhibits robust thermostability with a Tm of 83.2 °C and 41.7-fold enhanced PET hydrolytic activity at 60 °C compared with CaPETaseWT. CaPETaseM9 almost completely decompose both transparent and colored post-consumer PET powder at 55 °C within half a day in a pH-stat bioreactor.
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Actinomycetales , Hidrolasas , Hidrolasas/metabolismo , Tereftalatos Polietilenos/química , Estabilidad de Enzimas , Hidrólisis , Actinomycetales/metabolismoRESUMEN
Corynebacterium glutamicum (C. glutamicum) has been considered a very important and meaningful industrial microorganism for the production of amino acids worldwide. To produce amino acids, cells require nicotinamide adenine dinucleotide phosphate (NADPH), which is a biological reducing agent. The pentose phosphate pathway (PPP) can supply NADPH in cells via the 6-phosphogluconate dehydrogenase (6PGD) enzyme, which is an oxidoreductase that converts 6-phosphogluconate (6PG) to ribulose 5-phosphate (Ru5P), to produce NADPH. In this study, we identified the crystal structure of 6PGD_apo and 6PGD_NADP from C. glutamicum ATCC 13032 (Cg6PGD) and reported our biological research based on this structure. We identified the substrate binding site and co-factor binding site of Cg6PGD, which are crucial for understanding this enzyme. Based on the findings of our research, Cg6PGD is expected to be used as a NADPH resource in the food industry and as a drug target in the pharmaceutical industry.
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Corynebacterium glutamicum , Corynebacterium glutamicum/metabolismo , NADP/metabolismo , Fosfogluconato Deshidrogenasa/metabolismo , Vía de Pentosa Fosfato , Aminoácidos/metabolismoRESUMEN
Ideonella sakaiensis is the bacterium that can survive by degrading polyethylene terephthalate (PET) plastic, and terephthalic acid (TPA) binding protein (IsTBP) is an essential periplasmic protein for uptake of TPA into the cytosol for complete degradation of PET. Here, we demonstrated that IsTBP has remarkably high specificity for TPA among 33 monophenolic compounds and two 1,6-dicarboxylic acids tested. Structural comparisons with 6-carboxylic acid binding protein (RpAdpC) and TBP from Comamonas sp. E6 (CsTphC) revealed the key structural features that contribute to high TPA specificity and affinity of IsTBP. We also elucidated the molecular mechanism underlying the conformational change upon TPA binding. In addition, we developed the IsTBP variant with enhanced TPA sensitivity, which can be expanded for the use of TBP as a biosensor for PET degradation.
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Burkholderiales , Comamonas , Ácidos Ftálicos , Ácidos Ftálicos/química , Hidrolasas/químicaRESUMEN
The amino acids l-arginine and l-ornithine are widely used in animal feed and as health supplements and pharmaceutical compounds. In arginine biosynthesis, acetylornithine aminotransferase (AcOAT) uses pyridoxal-5'-phosphate (PLP) as a cofactor for amino group transfer. Here, we determined the crystal structures of the apo and PLP complex forms of AcOAT from Corynebacterium glutamicum (CgAcOAT). Our structural observations revealed that CgAcOAT undergoes an order-to-disorder conformational change upon binding with PLP. Additionally, we observed that unlike other AcOATs, CgAcOAT exists as a tetramer. Subsequently, we identified the key residues involved in PLP and substrate binding based on structural analysis and site-directed mutagenesis. This study might provide structural insights on CgAcOAT, which can be utilized for the development of improved l-arginine production enzymes.
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Corynebacterium glutamicum , Corynebacterium glutamicum/metabolismo , Transaminasas/genética , Mutagénesis Sitio-Dirigida , Arginina , Cristalografía por Rayos XRESUMEN
The platform chemical 3-hydroxypropionic acid is used to synthesize various valuable materials, including bioplastics. Bifunctional malonyl-CoA reductase is a key enzyme in 3-hydroxypropionic acid biosynthesis as it catalyzes the two-step reduction of malonyl-CoA to malonate semialdehyde to 3-hydroxypropionic acid. Here, we report the cryo-EM structure of a full-length malonyl-CoA reductase protein from Chloroflexus aurantiacus (CaMCRFull). The EM model of CaMCRFull reveals a tandem helix architecture comprising an N-terminal (CaMCRND) and a C-terminal (CaMCRCD) domain. The CaMCRFull model also revealed that the enzyme undergoes a dynamic domain movement between CaMCRND and CaMCRCD due to the presence of a flexible linker between these two domains. Increasing the flexibility and extension of the linker resulted in a twofold increase in enzyme activity, indicating that for CaMCR, domain movement is crucial for high enzyme activity. We also describe the structural features of CaMCRND and CaMCRCD. This study reveals the protein structures underlying the molecular mechanism of CaMCRFull and thereby provides valuable information for future enzyme engineering to improve the productivity of 3-hydroxypropionic acid.
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Oxidorreductasas , Microscopía por Crioelectrón , Oxidorreductasas/metabolismoRESUMEN
BACKGROUND: The routine use of high-intensity statins should be considered carefully in elderly patients because of their higher risk of intolerance or adverse events. OBJECTIVES: We evaluated the impact of moderate-intensity statin with ezetimibe combination therapy compared with high-intensity statin monotherapy in elderly patients with atherosclerotic cardiovascular disease (ASCVD). METHODS: In this post hoc analysis of the RACING (RAndomized Comparison of Efficacy and Safety of Lipid-lowerING With Statin Monotherapy Versus Statin/Ezetimibe Combination for High-risk Cardiovascular Diseases) trial, patients were stratified by age (≥75 years and <75 years). The primary endpoint was a 3-year composite of cardiovascular death, major cardiovascular events, or nonfatal stroke. RESULTS: Among the 3,780 enrolled patients, 574 (15.2%) were aged ≥75 years. The rates of the primary endpoint were not different between the moderate-intensity statin with ezetimibe combination therapy group and the high-intensity statin monotherapy group among patients aged ≥75 years (10.6% vs 12.3%; HR: 0.87; 95% CI: 0.54-1.42; P = 0.581) and those <75 years (8.8% vs 9.4%; HR: 0.94; 95% CI: 0.74-1.18; P = 0.570) (P for interaction = 0.797). Moderate-intensity statin with ezetimibe combination therapy was associated with lower rates of intolerance-related drug discontinuation or dose reduction among patients aged ≥75 years (2.3% vs 7.2%; P = 0.010) and those <75 years (5.2% vs 8.4%; P < 0.001) (P for interaction = 0.159). CONCLUSIONS: Moderate-intensity statin with ezetimibe combination therapy showed similar cardiovascular benefits to those of high-intensity statin monotherapy with lower intolerance-related drug discontinuation or dose reduction in elderly patients with ASCVD having a higher risk of intolerance, nonadherence, and discontinuation with high-intensity statin therapy. (RAndomized Comparison of Efficacy and Safety of Lipid-lowerING With Statin Monotherapy Versus Statin/Ezetimibe Combination for High-risk Cardiovascular Diseases [RACING Trial]; NCT03044665).
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Anticolesterolemiantes , Aterosclerosis , Enfermedades Cardiovasculares , Inhibidores de Hidroximetilglutaril-CoA Reductasas , Anciano , Humanos , Inhibidores de Hidroximetilglutaril-CoA Reductasas/uso terapéutico , Ezetimiba , Anticolesterolemiantes/uso terapéutico , Enfermedades Cardiovasculares/etiología , Quimioterapia Combinada , Aterosclerosis/tratamiento farmacológico , Lípidos , Resultado del TratamientoRESUMEN
Methylorubrum extorquens, a facultative methylotroph, assimilates C1 compounds and accumulates poly-ß-hydroxylbutyrate (PHB) as carbon and energy sources. The ethylmalonyl pathway is central to the carbon metabolism of M. extorquens, and is linked with a serine cycle and a PHB biosynthesis pathway. Understanding the ethylmalonyl pathway is vital in utilizing methylotrophs to produce value-added chemicals. In this study, we determined the crystal structure of the mesaconyl-CoA hydratase from M. extorquens (MeMeaC) that catalyzes the reversible conversion of mesaconyl-CoA to ß-methylmalyl-CoA. The crystal structure of MeMeaC revealed that the enzyme belongs to the MaoC-like dehydratase domain superfamily and functions as a trimer. In our current MeMeaC structure, malic acid occupied the substrate binding site, which reveals how MeMeaC recognizes the ß-methylmalyl-moiety of its substrate. The active site of the enzyme was further speculated by comparing its structure with those of other MaoC-like hydratases.
Asunto(s)
Acilcoenzima A , Carbono , Acilcoenzima A/metabolismo , Carbono/metabolismo , Vías BiosintéticasRESUMEN
Vanillin (3-methoxy-4-hydroxybenzaldehyde) is one of the most important flavoring substances used in the cosmetic and food industries. Feruloyl-CoA hydratase/lyase (FCHL) is an enzyme that catalyzes the production of vanillin from feruloyl-CoA. In this study, we report kinetic parameters and biochemical properties of FCHL from Sphingomonas paucimobilis SYK-6 (SpFCHL). Also, the crystal structures of an apo-form of SpFCHL and two complexed forms with acetyl-CoA and vanillin/CoA was present. Comparing the apo structure to its complexed forms of SpFCHL, a gate loop with an "open and closed" role was observed at the entrance of the substrate-binding site. With vanillin and CoA complexed to SpFCHL, we captured a conformational change in the feruloyl moiety-binding pocket that repositions the catalytic SpFCHLE146 and other key residues. This binding pocket does not tightly fit the vanillin structure, suggesting substrate promiscuity of this enzyme. This observation is in good agreement with assay results for phenylpropanoid-CoAs and indicates important physicochemical properties of the substrate for the hydratase/lyase reaction mechanism. In addition, we showed that various phenolic aldehydes could be produced using the 4CL-FCHL biosynthesis platform.