小狗阅读会员会员
医学顶刊SCI精读工具

扫码登录小狗阅读

阅读SCI医学文献
Document
订阅泛读方向 订阅泛读期刊
  • 我的关注
  • 我的关注
  • {{item.title}}

    按需关注领域/方向,精准获取前沿热点

  • {{item.title}}

    {{item.follow}}人关注

  • {{item.subscribe_count}}人订阅

    IF:{{item.impact_factor}}

    {{item.title}}

Integrating pathway elucidation with yeast engineering to produce polpunonic acid the precursor of the anti-obesity agent celastrol

整合途径解析与酵母工程生产抗肥胖剂雷公藤红素前体的聚丙酮酸

  • 影响因子:4.43
  • DOI:10.1186/s12934-020-1284-9
  • 作者列表:"Nikolaj L. Hansen","Karel Miettinen","Yong Zhao","Codruta Ignea","Aggeliki Andreadelli","Morten H. Raadam","Antonios M. Makris","Birger L. Møller","Dan Stærk","Søren Bak","Sotirios C. Kampranis
  • 发表时间:2020-02-02
Abstract

Abstract Background Celastrol is a promising anti-obesity agent that acts as a sensitizer of the protein hormone leptin. Despite its potent activity, a sustainable source of celastrol and celastrol derivatives for further pharmacological studies is lacking. Results To elucidate the celastrol biosynthetic pathway and reconstruct it in Saccharomyces cerevisiae, we mined a root-transcriptome of Tripterygium wilfordii and identified four oxidosqualene cyclases and 49 cytochrome P450s as candidates to be involved in the early steps of celastrol biosynthesis. Using functional screening of the candidate genes in Nicotiana benthamiana, TwOSC4 was characterized as a novel oxidosqualene cyclase that produces friedelin, the presumed triterpenoid backbone of celastrol. In addition, three P450s (CYP712K1, CYP712K2, and CYP712K3) that act downstream of TwOSC4 were found to effectively oxidize friedelin and form the likely celastrol biosynthesis intermediates 29-hydroxy-friedelin and polpunonic acid. To facilitate production of friedelin, the yeast strain AM254 was constructed by deleting UBC7, which afforded a fivefold increase in friedelin titer. This platform was further expanded with CYP712K1 to produce polpunonic acid and a method for the facile extraction of products from the yeast culture medium, resulting in polpunonic acid titers of 1.4 mg/L. Conclusion Our study elucidates the early steps of celastrol biosynthesis and paves the way for future biotechnological production of this pharmacologically promising compound in engineered yeast strains.

摘要

【摘要】背景雷公藤红素是一种很有前途的抗肥胖药物,可作为蛋白激素瘦素的增敏剂。尽管其有效的活性,但缺乏用于进一步药理研究的可持续来源的雷公藤红素和雷公藤红素衍生物。结果为了阐明雷公藤红素的生物合成途径并在酿酒酵母中进行重建, 我们挖掘了雷公藤的一个根转录组,确定了 4 种氧化环化酶和 49 种细胞色素 p450 作为候选物参与雷公藤红素生物合成的早期步骤。通过对烟草中候选基因的功能筛选,TwOSC4 被表征为一种新的氧化环化酶,产生 friedelin,即雷公藤红素的推测三萜骨架。此外,发现作用于 TwOSC4 下游的 3 个 p450 (CYP712K1 、 CYP712K2 和 CYP712K3) 有效氧化 friedelin,形成可能的雷公藤红素生物合成中间体 29-羟基-friedelin 和 poronic 酸。为了促进 friedelin 的生产,通过删除 UBC7 构建了酵母菌株 AM254,使 friedelin 滴度增加了 5 倍。利用 CYP712K1 进一步扩展了该平台,以生产 polponic acid 和从酵母培养基中简便提取产物的方法,获得了 1.4 mg/L 的 polponic acid 滴度。结论我们的研究阐明了雷公藤红素生物合成的早期步骤,并为未来在工程酵母菌株中生物技术生产这种药理学上有前途的化合物铺平了道路。

阅读人数:0人
下载该文献
小狗阅读

帮助医生、学生、科研工作者解决SCI文献找不到、看不懂、阅读效率低的问题。提供领域精准的SCI文献,通过多角度解析提高文献阅读效率,从而使用户获得有价值研究思路。

相关文献
影响因子:4.51
发表时间:2020-01-24
来源期刊:Nutrients
DOI:10.3390/nu12010090
作者列表:["Stephen Morehen","Benoit Smeuninx","Molly Perkins","Paul Morgan","Leigh Breen"]

METHODS:Maintaining adequate daily protein intake is important to maintain muscle mass throughout the lifespan. In this regard, the overnight period has been identified as a window of opportunity to increase protein intake in the elderly. However, it is unknown whether pre-sleep protein intake affects next-morning appetite and, consequently, protein intake. Therefore, the purpose of the current study was to investigate the effects of a pre-sleep protein drink on next-morning appetite, energy intake and metabolism. Twelve older individuals (eight males, four females; age: 71.3 ± 4.2 years) took part in a single-blind randomised cross-over study. After a standardised dinner, participants consumed either a 40-g protein drink, isocaloric maltodextrin drink, or placebo water control before bedtime. Next-morning appetite, energy intake, resting metabolic rate (RMR), respiratory exchange rate (RER), and plasma acylated ghrelin, leptin, glucose, and insulin concentrations were assessed. No between-group differences were observed for appetite and energy intake at breakfast. Furthermore, RMR, RER, and assessed blood markers were not significantly different between any of the treatment groups. Pre-sleep protein intake does not affect next-morning appetite and energy intake and is therefore a viable strategy to increase daily protein intake in an older population.

翻译标题与摘要 下载文献
影响因子:4.32
发表时间:2020-01-24
DOI:10.3390/ijms21010123
作者列表:["Tzi-Peng Yang","Hsiao-Mei Chen","Chao-Chin Hu","Li-Yuan Chen","Fen-Fen Shih","Disline Manli Tantoh","Kuan-Jung Lee","Yi-Chia Liaw","Rong-Tzong Tsai","Yung-Po Liaw"]

METHODS:Leptin (LEP) regulates glucose metabolism and energy storage in the body. Osteoarthritis (OA) is associated with the upregulation of serum LEP. LEP promoter methylation is associated with obesity. So far, few studies have explored the association of BMI and OA with LEP methylation. We assessed the interaction between body mass index (BMI) and OA on LEP promoter methylation. Data of 1114 participants comprising 583 men and 558 women, aged 30−70 years were retrieved from the Taiwan Biobank Database (2008−2015). Osteoarthritis was self-reported and cases were those who reported having ever been clinically diagnosed with osteoarthritis. BMI was categorized into underweight, normal weight, overweight, and obesity. The mean LEP promoter methylation level in individuals with osteoarthritis was 0.5509 ± 0.00437 and 0.5375 ± 0.00101 in those without osteoarthritis. The interaction between osteoarthritis and BMI on LEP promoter methylation was significant (p-value = 0.0180). With normal BMI as the reference, the mean LEP promoter methylation level was significantly higher in obese osteoarthritic individuals (β = 0.03696, p-value = 0.0187). However, there was no significant association between BMI and LEP promoter methylation in individuals without osteoarthritis, regardless of BMI. In conclusion, only obesity was significantly associated with LEP promoter methylation (higher levels) specifically in osteoarthritic patients.

翻译标题与摘要 下载文献
影响因子:4.82
发表时间:2020-01-01
DOI:10.1038/s41366-019-0368-2
作者列表:["Wulan, Siti N.","Schrauwen-Hinderling, Vera B.","Westerterp, Klaas R.","Plasqui, Guy"]

METHODS:Background For the same BMI, South Asians have a higher body fat percentage, a higher liver fat content and a more adverse metabolic profile than whites. South Asians may have a lower fat oxidation than whites, which could result in an unfavorable metabolic profile when exposed to increased high-fat foods consumption and decreased physical activity as in current modern lifestyle. Objective To determine substrate partitioning, liver fat accumulation and metabolic profile in South Asian and white men in response to overfeeding with high-fat diet under sedentary conditions in a respiration chamber. Design Ten South Asian men (BMI, 18–29 kg/m^2) and 10 white men (BMI, 22–33 kg/m^2), matched for body fat percentage, aged 20–40 year were included. A weight maintenance diet (30% fat, 55% carbohydrate, and 15% protein) was given for 3 days. Thereafter, a baseline measurement of liver fat content (1H-MRS) and blood parameters was performed. Subsequently, subjects were overfed (150% energy requirement) with a high-fat diet (60% fat, 25% carbohydrate, and 15% protein) over 3 consecutive days while staying in a respiration chamber mimicking a sedentary lifestyle. Energy expenditure and substrate use were measured for 3 × 24-h. Liver fat and blood parameters were measured again after the subjects left the chamber. Results The 24-h fat oxidation as a percentage of total energy expenditure did not differ between ethnicities ( P  = 0.30). Overfeeding increased liver fat content ( P  = 0.02), but the increase did not differ between ethnicities ( P  = 0.64). In South Asians, overfeeding tended to increase LDL-cholesterol ( P  = 0.08), tended to decrease glucose clearance ( P  = 0.06) and tended to elevate insulin response ( P  = 0.07) slightly more than whites. Conclusions Despite a similar substrate partitioning and similar accretion of liver fat, overfeeding with high-fat under sedentary conditions tended to have more adverse effects on the lipid profile and insulin sensitivity in South Asians.

关键词: 暂无
翻译标题与摘要 下载文献
方向

复制标题
发送后即可在该邮箱或我的下载查看该文献
发送
该文献默认存储到我的下载

报名咨询

建议反馈
问题标题:
联系方式:
电子邮件:
您的需求: