Acyltransferases

酰基转移酶
  • 文章类型: Journal Article
    背景:代谢功能障碍相关脂肪性肝炎(MASH)是代谢功能障碍相关脂肪性肝病的一种进行性形式,关于患者经验的信息有限,包括耐心的旅程。
    方法:在本研究中,我们对MASH患者进行了访谈,以定性评估患者的旅程,并帮助阐明该患者人群的经历.我们还调查了patatin样磷脂酶结构域含蛋白3(PNPLA3)I148M变体(非西班牙裔)或西班牙裔种族是否可能影响患者的经历,因为这两个亚组比其他患者组更频繁地发展为晚期肝病。
    结果:对28名成年人进行了一对一的访谈(具有PNPLA3I148M遗传变异,n=10;西班牙裔,n=8)生活在美国,已被诊断出患有肝纤维化的MASH。患者被问到关于他们以前的经历的开放式问题,at,在他们的诊断之后。收集的数据发现,患者在诊断MASH之前经历了漫长的误诊过程,缺乏临床医生提供的明确信息,以及支持团体的可访问性有限。与其他接受采访的患者相比,西班牙裔患者报告“对家人/朋友的影响”(75%)和“对疾病进展的恐惧”(75%)的频率更高。这是MASH患者的“对进展的恐惧”的第一份报告。没有白人患者和有PNPLA3I148M变异报告恶心/呕吐。与其他患者队列相反。
    结论:这项定性研究确定了患者旅程的关键方面,这些方面对于临床提供者和医疗团队来说很重要。我们还提出了一种新算法,可以开发该算法来帮助筛查被发现携带PNPLA3I148M变体的患者的亲属。
    BACKGROUND: Metabolic dysfunction-associated steatohepatitis (MASH) is a progressive form of metabolic dysfunction-associated steatotic liver disease, for which there is limited information about patient experience, including the patient journey.
    METHODS: In this study, we conducted interviews with patients with MASH to qualitatively evaluate the patient journey and help elucidate the experiences of this patient population. We also investigated if the patatin-like phospholipase domain-containing protein 3 (PNPLA3) I148M variant (non-Hispanic) or being of Hispanic ethnicity may influence patient experiences because these 2 subgroups develop advanced liver disease more frequently than other patient groups.
    RESULTS: One-to-one interviews were conducted with 28 adults (with PNPLA3 I148M genetic variant, n = 10; Hispanic, n = 8) living in the United States who had been diagnosed with MASH with liver fibrosis. Patients were asked open-ended questions about their experiences before, at, and after their diagnosis. The data collected found that patients experienced a long process of misdiagnoses before their diagnosis of MASH, a lack of clear information provided by clinicians, and limited accessibility to support groups. Hispanic patients reported \"impact on family/friends\" (75%) and \"fear of disease progression\" (75%) more frequently than the other patient cohorts interviewed. This is the first report of \"fear of progression\" in patients with MASH. No patients who were White and had the PNPLA3 I148M variant reported nausea/vomiting, in contrast to other patient cohorts.
    CONCLUSIONS: This qualitative study identified key aspects of the patient journey that are important for clinical providers and medical teams to recognize. We also propose a new algorithm that could be developed to help screen relatives of patients who are found to carry the PNPLA3 I148M variant.
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  • 文章类型: Journal Article
    全基因组关联研究已经确定了与非酒精性脂肪肝疾病相关的几种遗传变异。为了强调脂肪肝的代谢异常,代谢(功能障碍)相关的脂肪肝疾病(MAFLD)已经被引入;因此,我们旨在研究与MAFLD及其亚型相关的单核苷酸多态性。进行了全基因组关联研究以鉴定与MAFLD相关的遗传因素。我们使用了基于韩国人群的2282名MAFLD受试者和一个4669名对照组的样本。我们在包括639例MAFLD患者和1578例对照的验证样本中复制了结果。此外,我们将参与者分为三组,没有MAFLD,代谢功能障碍(MD)-MAFLD,和超重/肥胖-MAFLD。在调整了年龄之后,性别,和主成分得分,rs738409[风险等位基因G]和rs3810622[风险等位基因T],位于PNPLA3基因中,显示与MAFLD显著相关(P值,发现集=1.60×10-15和4.84×10-10;赔率比,1.365和1.284,验证集=1.39×10-4,和7.15×10-4,赔率比,分别为1.299和1.264)。位于GATAD2A基因中的另一个SNPrs59148799[风险等位基因G]显示出与MAFLD的显着关联(P值,发现集=2.08×10-8,验证集=0.034,赔率比,1.387和1.250)。rs738409与MAFLD亚型显著相关([超重/肥胖-MAFLD;比值比(95%置信区间),P值,1.515(1.351-1.700),1.43×10-12和MD-MAFLD:1.300(1.191-1.416),2.90×10-9]。rs3810622与超重/肥胖-MAFLD和MD-MAFLD之间存在显著关系[优势比(95%置信区间),P值,1.418(1.258,1.600),1.21×10-8和1.225(1.122,1.340),7.06×10-6,分别];统计显著性保留在验证集中。在韩国人群中,PNPLA3与MAFLD和MAFLD亚型显着相关。这些结果表明遗传因素在MAFLD的发病中起重要作用。
    Genome-wide association studies have identified several genetic variants associated with nonalcoholic fatty liver disease. To emphasize metabolic abnormalities in fatty liver, metabolic (dysfunction)-associated fatty liver disease (MAFLD) has been introduced; thus, we aimed to investigate single-nucleotide polymorphisms related to MAFLD and its subtypes. A genome-wide association study was performed to identify genetic factors related to MAFLD. We used a Korean population-based sample of 2282 subjects with MAFLD and a control group of 4669. We replicated the results in a validation sample which included 639 patients with MAFLD and 1578 controls. Additionally, we categorized participants into three groups, no MAFLD, metabolic dysfunction (MD)-MAFLD, and overweight/obese-MAFLD. After adjusting for age, sex, and principal component scores, rs738409 [risk allele G] and rs3810622 [risk allele T], located in the PNPLA3 gene, showed significant associations with MAFLD (P-values, discovery set = 1.60 × 10-15 and 4.84 × 10-10; odds ratios, 1.365 and 1.284, validation set = 1.39 × 10-4, and 7.15 × 10-4, odds ratios, 1.299 and 1.264, respectively). An additional SNP rs59148799 [risk allele G] located in the GATAD2A gene showed a significant association with MAFLD (P-values, discovery set = 2.08 × 10-8 and validation set = 0.034, odds ratios, 1.387 and 1.250). rs738409 was significantly associated with MAFLD subtypes ([overweight/obese-MAFLD; odds ratio (95% confidence interval), P-values, 1.515 (1.351-1.700), 1.43 × 10-12 and MD-MAFLD: 1.300 (1.191-1.416), 2.90 × 10-9]. There was a significant relationship between rs3810622 and overweight/obese-MAFLD and MD-MAFLD [odds ratios (95% confidence interval), P-values, 1.418 (1.258, 1.600), 1.21 × 10-8 and 1.225 (1.122, 1.340), 7.06 × 10-6, respectively]; the statistical significance remained in the validation set. PNPLA3 was significantly associated with MAFLD and MAFLD subtypes in the Korean population. These results indicate that genetic factors play an important role in the pathogenesis of MAFLD.
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  • 文章类型: Journal Article
    据报道,复杂的微生物群落与牙髓感染有关。微生物侵入牙髓,导致牙髓炎并引发牙髓炎症。核梭杆菌是主要细菌,涉及原发性和继发性牙髓感染。靶向F.核仁的分子机制的药物将最大程度地减少牙髓感染。LpxA和LpxD是参与脂质A形成的早期酰基转移酶,细菌膜的主要组成部分。鉴定在单个途径中对连续酶表现出偏好的前导还可以防止细菌抗性的发展。严格的筛选策略利用物理化学和药代动力学参数以及虚拟筛选方法确定了两种化合物,洛美沙星和依诺沙星,对早期酰基转移酶LpxA和LpxD具有良好的结合亲和力。洛美沙星和依诺沙星,氟喹诺酮类抗生素的成员,对不同的细菌菌株表现出广泛的活性。然而,它们在牙髓治疗中的有效性需要进一步研究.这项研究探索了洛美沙星和依诺沙星通过计算分析管理牙髓感染的潜力。此外,本文鉴定的化合物作为设计新型组合文库的基础,所述组合文库具有增强的用于牙髓治疗策略的功效。
    Complex microbial communities have been reported to be involved in endodontic infections. The microorganisms invade the dental pulp leading to pulpitis and initiating pulp inflammation. Fusobacterium nucleatum is a dominant bacterium implicated in both primary and secondary endodontic infections. Drugs targeting the molecular machinery of F. nucleatum will minimize pulp infection. LpxA and LpxD are early acyltransferases involved in the formation of lipid A, a major component of bacterial membranes. The identification of leads which exhibit preference towards successive enzymes in a single pathway can also prevent the development of bacterial resistance. A stringent screening strategy utilizing physicochemical and pharmacokinetic parameters along with a virtual screening approach identified two compounds, Lomefloxacin and Enoxacin, with good binding affinity towards the early acyltransferases LpxA and LpxD. Lomefloxacin and Enoxacin, members of the fluoroquinolone antibiotic class, exhibit wide-ranging activity against diverse bacterial strains. Nevertheless, their effectiveness in the context of endodontic treatment requires further investigation. This study explored the potential of Lomefloxacin and Enoxacin to manage endodontic infections via computational analysis. Moreover, the compounds identified herein serve as a foundation for devising novel combinatorial libraries with enhanced efficacy for endodontic therapeutic strategies.
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  • 文章类型: Journal Article
    背景:肥胖是能量摄入(EI)长期超过能量消耗的结果。然而,潜在的代谢因素,包括胰岛素抵抗,仍然不清楚。这项研究纵向调查了与体重变化相关的因素。
    方法:在4年的随访中对707名没有糖尿病的成年人进行了调查。使用经过验证的食物频率问卷对过去12个月的能量和大量营养素的习惯性摄入量进行评估。β细胞功能和胰岛素抵抗的稳态模型评估(HOMA-IR)用作胰岛素抵抗的替代测量。此外,对PNPLA3进行基因分型。
    结果:87名参与者是体重增加者(G;截止值=5公斤),620为非涨幅者(NG)。初始人体测量(Gvs.NG:年龄,44±13vs51±13年,P<0.001;体重指数,27.8±6.5vs28.1±5.1kg/m2,P=ns;体重,76.7±22.1vs74.2±14.7kg,P=ns;最终体重,86.3±23.7vs72.9±14.2kg,P<0.001)和饮食特征,以及胰岛素浓度和HOMA-IR值,两组相似。四年后,G显示EI显著增加,胰岛素浓度,和HOMA-IR值。G的PNPLA3CG和GG等位基因的患病率高于NG(P<0.05)。G的存在与年龄独立相关(OR=1.031),EI变化(OR=2.257),和PNPLA3基因的不良等位基因(OR=1.700)。最终体重指数,腰围,EI与最终HOMA-IR独立相关(P<0.001)。
    结论:EI与体重增加有关,遗传因素可能会影响能量平衡。胰岛素抵抗是体重增加的结果,提示可能的细胞内保护机制对抗底物溢出。
    背景:ISRCTN15840340。
    BACKGROUND: Obesity is the result of energy intake (EI) chronically exceeding energy expenditure. However, the potential metabolic factors, including insulin resistance, remain unclear. This study longitudinally investigated factors associated with changes in body weight.
    METHODS: A cohort of 707 adults without diabetes were investigated at the 4-year follow-up visit. The habitual intake of energy and macronutrients during the past 12 months was assessed using a validated Food Frequency Questionnaire for the local population. Homeostatic model assessment of β-cell function and insulin resistance (HOMA-IR) was used as a surrogate measure of insulin resistance. Additionally, PNPLA3 was genotyped.
    RESULTS: Eighty-seven participants were weight gainers (G; cutoff value = 5 kg), and 620 were non-gainers (NG). Initial anthropometric (G vs. NG: age, 44 ± 13 vs 51 ± 13 years, P < 0.001; body mass index, 27.8 ± 6.5 vs 28.1 ± 5.1 kg/m2, P = ns; body weight, 76.7 ± 22.1 vs 74.2 ± 14.7 kg, P = ns; final body weight, 86.3 ± 23.7 vs 72.9 ± 14.2 kg, P < 0.001) and diet characteristics, as well as insulin concentrations and HOMA-IR values, were similar in both groups. Four years later, G showed significantly increased EI, insulin concentrations, and HOMA-IR values. G had a higher prevalence of the PNPLA3 CG and GG alleles than NG (P < 0.05). The presence of G was independently associated with age (OR = 1.031), EI change (OR = 2.257), and unfavorable alleles of PNPLA3 gene (OR = 1.700). Final body mass index, waist circumference, and EI were independently associated with final HOMA-IR (P < 0.001).
    CONCLUSIONS: EI is associated with body weight gain, and genetic factors may influence the energy balance. Insulin resistance is a consequence of weight gain, suggesting a possible intracellular protective mechanism against substrate overflow.
    BACKGROUND: ISRCTN15840340.
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  • 文章类型: Journal Article
    背景:常染色体隐性遗传先天性鱼鳞病(ARCI)是一组临床异质性的角质化疾病,其特征是由于至少12个基因的突变而导致的全身性皮肤鳞屑。我们研究的目的是评估疾病的严重程度,ARCI患者的表型和超微结构特征,并评估其与遗传发现的关联。
    方法:临床体征和症状,在单中心系列的ARCI基因诊断患者中对疾病严重程度进行评分.对皮肤超微结构的发现进行了综述。
    结果:连续74例患者(平均年龄11.0岁,范围0.1-48.8)受层状鱼鳞病影响(50/74,67.5%),先天性鱼鳞状红皮病(18/74,24.3%),丑角鱼鳞病(2/74,2.7%),和其他次要ARCI亚型(4/74,5.4%)入组.突变基因为:18/74(24.3%)患者中的TGM1,ALOX12B在18/74(24.3%),CYP4F22在12/74(16.2%),ABCA12在9/74(12.2%),ALOXE3在7/74(9.5%),NIPAL4在7/74(9.5%),CERS3、PNPLA1和SDR9C7各1例(1.4%)。在不同的ARCI致病基因中,有25个以前未描述的突变,以及TGM1中的两个微重复,以及CYP4F22和NIPAL4中的两个微缺失。TGM1和ABCA12突变患者的鱼鳞病严重程度平均评分明显高于所有其他突变基因,而在CYP4F22突变的患者中观察到最低评分。脱发,外翻,和eclabium与TGM1和ABCA12突变显著相关,而且很大,有TGM1突变的厚褐色鳞片。在特定的表型特征中,在NIPAL4突变的患者中存在牛皮癣样病变以及躯干网状鳞屑模式和横纹角化病。56例患者的超微结构数据显示,TGM1突变病例的胆固醇裂口具有100%的特异性,并在SDR9C7和CERS3患者中发现异常的层状体。
    结论:我们的研究通过描述疾病严重程度之间的统计学显着关联来扩展ARCI的表型和遗传特征。具体的临床体征,和不同的变异基因.最后,我们强调NIPAL4-ARCI患者中存在银屑病样病变是一种新的表型特征,具有诊断和可能的治疗意义.
    BACKGROUND: Autosomal recessive congenital ichthyoses (ARCIs) are a clinically heterogeneous group of keratinization disorders characterized by generalized skin scaling due to mutations in at least 12 genes. The aim of our study was to assess disease severity, phenotypic, and ultrastructural features and to evaluate their association with genetic findings in ARCI patients.
    METHODS: Clinical signs and symptoms, and disease severity were scored in a single-center series of patients with a genetic diagnosis of ARCI. Skin ultrastructural findings were reviewed.
    RESULTS: Seventy-four consecutive patients (mean age 11.0 years, range 0.1-48.8) affected with lamellar ichthyosis (50/74, 67.5%), congenital ichthyosiform erythroderma (18/74, 24.3%), harlequin ichthyosis (two/74, 2.7%), and other minor ARCI subtypes (four/74, 5.4%) were enrolled. Mutated genes were as follows: TGM1 in 18/74 (24.3%) patients, ALOX12B in 18/74 (24.3%), CYP4F22 in 12/74 (16.2%), ABCA12 in nine/74 (12.2%), ALOXE3 in seven/74 (9.5%), NIPAL4 in seven/74 (9.5%), and CERS3, PNPLA1, and SDR9C7 in 1 patient each (1.4%). Twenty-five previously undescribed mutations in the different ARCI causative genes, as well as two microduplications in TGM1, and two microdeletions in CYP4F22 and NIPAL4 were identified. The mean ichthyosis severity score in TGM1- and ABCA12-mutated patients was significantly higher than in all other mutated genes, while the lowest score was observed in CYP4F22-mutated patients. Alopecia, ectropion, and eclabium were significantly associated with TGM1 and ABCA12 mutations, and large, thick, and brownish scales with TGM1 mutations. Among specific phenotypic features, psoriasis-like lesions as well as a trunk reticulate scale pattern and striated keratoderma were present in NIPAL4-mutated patients. Ultrastructural data available for 56 patients showed a 100% specificity of cholesterol clefts for TGM1-mutated cases and revealed abnormal lamellar bodies in SDR9C7 and CERS3 patients.
    CONCLUSIONS: Our study expands the phenotypic and genetic characterization of ARCI by the description of statistically significant associations between disease severity, specific clinical signs, and different mutated genes. Finally, we highlighted the presence of psoriasis-like lesions in NIPAL4-ARCI patients as a novel phenotypic feature with diagnostic and possible therapeutic implications.
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  • 文章类型: Journal Article
    目的:含Patatin样磷脂酶结构域3基因(PNPLA3)多态性与非酒精性脂肪性肝病(NAFLD)的易感性有关,与营养潜在相互作用的证据。然而,肉类消费与遗传多态性的结合尚未进行测试。因此,本研究旨在检验在不同肉类消费人群中,高肉类消费的PNPLA3rs738409G等位基因的联合存在与NAFLD之间的关联.
    方法:一项针对以色列筛查和巴西初级卫生保健人群的横断面研究。通过食物频率问卷评估食物消耗。PNPLA3多态性定义为纯合(GG)或杂合(GC)。不确定/可能的NAFLD定义为脂肪肝指数(FLI)≥30,可能的NAFLD定义为FLI≥60。
    结果:样本包括来自筛查和初级保健人群的511名受试者(分别为n=213和n=298)。遗传多态性(纯合GG或杂合GC)与高食用总肉相结合,红色和/或加工肉,未经加工的红肉,加工肉与不确定/可能的NAFLD的几率最高(OR=2.75,95CI1.27-5.97,p=0.011;OR=3.24,1.43-7.34,p=0.005;OR=2.92,1.32-6.47,p=0.008;OR=3.16,1.46-6.83,p=0.003),调整年龄,性别,BMI,酒精消费,碳水化合物,和饱和脂肪的摄入量。此外,遗传多态性与高加工肉食摄入量相关的可能性最高(OR=2.40,95CI1.04-5.56,p=0.040).
    结论:在PNPLA3多态性携带者中,高红肉摄入可能会增加NAFLD的风险。需要进行前瞻性研究以确认这些发现,并考虑在PNPLA3多态性携带者中尽量减少红肉和加工肉的消费。
    OBJECTIVE: Patatin-like phospholipase domain-containing 3 gene (PNPLA3) polymorphism has been implicated in susceptibility to non-alcoholic fatty liver disease (NAFLD), with evidence for potential interaction with nutrition. However, the combination of meat consumption with genetic polymorphism has not been tested. Therefore, this study aims to test the association between the joint presence of PNPLA3 rs738409 G-allele with high meat consumption and NAFLD in populations with diverse meat consumption.
    METHODS: A cross-sectional study among Israeli screening and Brazilian primary healthcare populations. Food consumption was assessed by a food-frequency questionnaire. PNPLA3 polymorphism was defined as homozygous (GG) or heterozygous (GC). Inconclusive/probable NAFLD was defined as a fatty liver index (FLI) ≥ 30 and probable NAFLD as FLI ≥ 60.
    RESULTS: The sample included 511 subjects from the screening and primary healthcare populations (n = 213 and n = 298, respectively). Genetic polymorphism (homozygous GG or heterozygous GC) combined with high consumption of total meat, red and/or processed meat, unprocessed red meat, and processed meat was associated with the highest odds for inconclusive/probable NAFLD (OR = 2.75, 95%CI 1.27-5.97, p = 0.011; OR = 3.24, 1.43-7.34, p = 0.005; OR = 2.92, 1.32-6.47, p = 0.008; OR = 3.16, 1.46-6.83, p = 0.003, respectively), adjusting for age, gender, BMI, alcohol consumption, carbohydrate, and saturated fat intake. In addition, genetic polymorphism combined with high processed meat consumption was associated with the highest odds for probable NAFLD (OR = 2.40, 95%CI 1.04-5.56, p = 0.040).
    CONCLUSIONS: High red meat intake may confer a greater risk for NAFLD among PNPLA3 polymorphism carriers. Prospective studies are needed to confirm these findings and consider minimizing red and processed meat consumption among PNPLA3 polymorphism carriers.
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  • 文章类型: Clinical Study
    确定社区获得性肺炎(CAP)患者的诊断和预后仍然具有挑战性。我们旨在确定溶血磷脂酰胆碱酰基转移酶(LPCAT)在CAP中的作用,并评估该蛋白作为疾病严重程度和死亡率的生物标志物的有效性。
    前瞻性多中心研究在住院患者中进行。共纳入299例CAP患者(包括97例重度CAP患者[SCAP])和20例健康对照(HC)。使用定量酶联免疫吸附测试试剂盒检测血浆中的LPCAT水平。我们开发了基于深度学习的二元分类(SCAP或非严重CAP[NSCAP])模型来处理LPCAT水平和其他实验室测试结果。
    SCAP患者的LPCAT水平和死亡结局明显高于其他患者。LPCAT对SCAP的预测价值最高。LPCAT能够预测CAP患者的30天死亡率,将LPCAT值与PSI评分或CURB-65相结合,可进一步提高死亡率预测的准确性.
    发现SCAP患者中LPCAT的入院水平显着升高,并强烈预测了SCAP患者,但与病因无关。将LPCAT值与CURB-65或PSI相结合,显着改善了30天死亡率预测。
    NCT03093220于3月28日注册,2017.
    Identifying the diagnosis as well as prognosis for patients presented with community-acquired pneumonia (CAP) remains challenging. We aimed to identify the role of lysophosphatidylcholine acyl-transferase (LPCAT) for CAP along with assessing this protein\'s effectiveness as a biomarker for severity of disease and mortality.
    Prospective multicenter research study was carried out among hospitalized patients. A total of 299 CAP patients (including 97 severe CAP patients [SCAP]) and 20 healthy controls (HC) were included. A quantitative enzyme-linked immunosorbent test kit was employed for detecting the LPCAT level in plasma. We developed a deep-learning-based binary classification (SCAP or non-severe CAP [NSCAP]) model to process LPCAT levels and other laboratory test results.
    The level of LPCAT in patients with SCAP and death outcome was significantly higher than that in other patients. LPCAT showed the highest predictive value for SCAP. LPCAT was able to predict 30-day mortality among CAP patients, combining LPCAT values with PSI scores or CURB-65 further enhance mortality prediction accuracy.
    The on admission level of LPCAT found significantly raised among SCAP patients and strongly predicted SCAP patients but with no correlation to etiology. Combining the LPCAT value with CURB-65 or PSI improved the 30-day mortality forecast significantly.
    NCT03093220 Registered on March 28th, 2017.
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  • 文章类型: Journal Article
    来自假单胞菌蛋白原的酰基转移酶(PpATase)在自然界中催化单乙酰间苯三酚向二乙酰间苯三酚和间苯三酚的可逆转化。有趣的是,该酶已被证明可以催化乙酸3-羟基苯酯向2'的混杂转化,4\'-二羟基苯乙酮,代表Fries重排的生物学版本。在本研究中,我们报告了使用量子化学计算对PpATase的这种活性进行的机理研究。提出了一种详细的机制,并给出了反应的能量分布。计算表明,酶的酰化是高度放热的,而转移回底物的乙酰基只是轻微放热。底物C6-H的去质子化是限速的,和远程天冬氨酸残基(Asp137)被建议作为该步骤中的一般碱基基团。对各种乙酰受体的结合能的分析表明,PpATase可以促进分子内和分子间Fries向多种化合物的重排。
    The acyltransferase from Pseudomonas protegens (PpATase) catalyzes in nature the reversible transformation of monoacetylphloroglucinol to diacetylphloroglucinol and phloroglucinol. Interestingly, this enzyme has been shown to catalyze the promiscuous transformation of 3-hydroxyphenyl acetate to 2\',4\'-dihydroxyacetophenone, representing a biological version of the Fries rearrangement. In the present study, we report a mechanistic investigation of this activity of PpATase using quantum chemical calculations. A detailed mechanism is proposed, and the energy profile for the reaction is presented. The calculations show that the acylation of the enzyme is highly exothermic, while the acetyl transfer back to the substrate is only slightly exothermic. The deprotonation of the C6-H of the substrate is rate-limiting, and a remote aspartate residue (Asp137) is proposed to be the general base group in this step. Analysis of the binding energies of various acetyl acceptors shows that PpATase can promote both intramolecular and intermolecular Fries rearrangement towards diverse compounds.
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  • 文章类型: Journal Article
    目的:PNPLA3-rs738409和TM6SF2-rs58542926的单核苷酸多态性,与代谢功能障碍相关的脂肪肝(MAFLD)相关,已被讨论为心血管疾病的潜在保护。因此,我们旨在研究基于人群的无症状患者样本中PNPLA3/TM6SF2变异与MAFLD和心血管风险的相关性.
    方法:该研究队列包括2010年至2014年接受结直肠癌结肠镜检查的注册研究中的1742名年龄在45-80岁的欧洲患者。计算SCORE2和Framingham风险评分以评估心血管风险。生存数据来自国家死亡登记结果:一半的纳入患者是男性(52%,59±10年),819个(47%)携带PNPLA3-G和278个(16%)TM6SF2-T等位基因。MAFLD(PNPLA3‑G等位基因:46%与41%,p=0.041;TM6SF2‑T等位基因:54%vs.42%,p<0.001)在具有风险等位基因的患者中更为常见,在多变量二元逻辑回归分析中,两者均显示与MAFLD的独立关联。而PNPLA3-G等位基因携带者的中位Framingham风险评分较低(10与8,p=0.011),SCORE2和已建立的心血管疾病在携带者与携带者之间相似。各自风险等位基因的非携带者。在9.1年的中位随访期间,PNPLA3‑G等位基因和TM6SF2‑T等位基因均不与总体死亡率或心血管死亡率相关.
    结论:在接受结肠镜检查的无症状中年人中,PNPLA3/TM6SF2危险等位基因的携带不能确定为全因死亡或心血管死亡的重要因素。
    OBJECTIVE: Single-nucleotide-polymorphisms in PNPLA3-rs738409 and the TM6SF2-rs58542926, associated with metabolic-dysfunction-associated fatty liver disease (MAFLD), have been discussed as potentially protective for cardiovascular diseases. Therefore, we aimed to study the associations of PNPLA3/TM6SF2 variants with MAFLD and cardiovascular risk in a population-based sample of asymptomatic patients.
    METHODS: The study cohort comprised 1742 patients of European decent aged 45-80 years from a registry study undergoing screening colonoscopy for colorectal cancer between 2010 and 2014. SCORE2 and Framingham risk score calculated to assess cardiovascular risk. Data on survival were obtained from the national death registry RESULTS: Half of included patients were male (52%, 59 ± 10 years), 819 (47%) carried PNPLA3‑G and 278 (16%) TM6SF2-T-alleles. MAFLD (PNPLA3‑G-allele: 46% vs. 41%, p = 0.041; TM6SF2‑T-allele: 54% vs. 42%, p < 0.001) was more frequent in patients harbouring risk alleles with both showing independent associations with MAFLD on multivariable binary logistic regression analysis. While median Framingham risk score was lower in PNPLA3‑G-allele carriers (10 vs. 8, p = 0.011), SCORE2 and established cardiovascular diseases were similar across carriers vs. non-carriers of the respective risk-alleles. During a median follow-up of 9.1 years, neither PNPLA3‑G-allele nor TM6SF2‑T-allele was associated with overall nor with cardiovascular mortality.
    CONCLUSIONS: Carriage of PNPLA3/TM6SF2 risk alleles could not be identified as significant factor for all-cause or cardiovascular mortality in asymptomatic middle-aged individuals undergoing screening colonoscopy.
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  • 文章类型: Journal Article
    阐明酶的结构以及底物如何与活性位点结合是了解其反应机理和功能的重要步骤。然而,获得蛋白质三维结构的方法,如X射线晶体学和核磁共振,可能是昂贵和耗时的。考虑到这一点,另一种选择是使用结构生物信息学工具从蛋白质的一级序列预测蛋白质的三级结构,然后将一种或多种底物分子对接到酶结构模型中。在过去的几年里,这些计算工具已经取得了重大进展,在使用物理方法解析结构之前,可以提供有关活性位点和酶-底物相互作用的有用信息。这里,以普通豆(菜豆)羟基肉桂酰辅酶A:四羟基己二酸羟基肉桂酰转移酶(HHHT)为例,我们描述了蛋白质结构预测和分子对接的方法和工作流程,这些方法和工作流程只能在个人计算机上使用开源工具进行。
    Elucidating the structure of an enzyme and how substrates bind to the active site is an important step for understanding its reaction mechanism and function. Nevertheless, the methods available to obtain three-dimensional structures of proteins, such as x-ray crystallography and NMR, can be expensive and time-consuming. Considering this, an alternative is using structural bioinformatic tools to predict the tertiary structure of a protein from its primary sequence, followed by molecular docking of one or more substrates into the enzyme structure model. In the past few years, significant advances have been made in these computational tools, which can give useful information about the active site and enzyme-substrate interactions before the structure can be resolved using physical methods. Here, using common bean (Phaseolus vulgaris) hydroxycinnamoyl-coenzyme A:tetrahydroxyhexanedioic acid hydroxycinnamoyltransferase (HHHT) as an example, we describe methods and workflows for protein structure prediction and molecular docking that can be performed on a personal computer using only open-source tools.
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