Palmitoleic acid

棕榈油酸
  • 文章类型: Journal Article
    晚期糖基化终产物(AGEs)在高血糖孕妇的血浆中积累,潜在诱导氧化应激和胎儿发育异常。尽管宫内高血糖与胎儿过度生长有关,母体AGEs对胎儿发育的影响尚不清楚.我们评估了控制母亲(ICM)出生的婴儿骨骼肌中的分化调节剂和细胞信号传导,糖尿病母亲(IDM),补充顺式棕榈油酸(CPA)或反式棕榈油酸(TPA)的糖尿病母亲。细胞活力,活性氧水平,在暴露于AGE的C2C12细胞中评估肌管形成,以探索CPA和TPA的潜在缓解。在IDM的大鼠骨骼肌中,AGE表达的受体升高,Akt和AMPK磷酸化降低。母亲补充棕榈油酸通过下调RAGE表达和增强Akt磷酸化来减轻胰岛素抵抗。C2C12细胞暴露于AGEs会降低细胞活力和肌管形成,并升高活性氧水平,通过补充CPA或TPA减毒。这表明母体高血糖和血浆AGEs可能导致后代骨骼肌疾病,补充棕榈油酸可以减轻这种情况。因此,孕妇在怀孕期间摄入棕榈油酸可能对胎儿健康有影响。
    Advanced glycation end products (AGEs) accumulate in the plasma of pregnant women with hyperglycemia, potentially inducing oxidative stress and fetal developmental abnormalities. Although intrauterine hyperglycemia has been implicated in excessive fetal growth, the effects of maternal AGEs on fetal development remain unclear. We evaluated the differentiation regulators and cellular signaling in the skeletal muscles of infants born to control mothers (ICM), diabetic mothers (IDM), and diabetic mothers supplemented with either cis-palmitoleic acid (CPA) or trans-palmitoleic acid (TPA). Cell viability, reactive oxygen species levels, and myotube formation were assessed in AGE-exposed C2C12 cells to explore potential mitigation by CPA and TPA. Elevated receptors for AGE expression and decreased Akt and AMPK phosphorylation were evident in rat skeletal muscles in IDM. Maternal palmitoleic acid supplementation alleviated insulin resistance by downregulating RAGE expression and enhancing Akt phosphorylation. The exposure of the C2C12 cells to AGEs reduced cell viability and myotube formation and elevated reactive oxygen species levels, which were attenuated by CPA or TPA supplementation. This suggests that maternal hyperglycemia and plasma AGEs may contribute to skeletal muscle disorders in offspring, which are mitigated by palmitoleic acid supplementation. Hence, the maternal intake of palmitoleic acid during pregnancy may have implications for fetal health.
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  • 文章类型: Journal Article
    这项工作描述了涉及单不饱和脂肪酸棕榈油酸的磷脂脂肪酸重塑的新途径。当施用于人类单核细胞时,棕榈油酸迅速掺入膜磷脂,特别是磷脂酰胆碱(PC)。在静息细胞中,棕榈油酸保留在最初掺入的磷脂池中,没有进一步的运动。然而,用受体定向的(调理的酵母聚糖)或可溶性(钙离子载体A23187)激动剂刺激人单核细胞导致棕榈油酸部分从PC快速转移到磷脂酰肌醇(PI)。这是由于辅酶A依赖性重塑途径的激活,该途径涉及两种不同的磷脂酶A2酶,它们作用于不同的底物以产生游离的棕榈油酸和溶素PI受体。用棕榈油酸刺激特定PI分子物种的富集揭示了迄今为止未被识别的人单核细胞脂质周转途径,该途径可能在先天免疫激活期间调节脂质信号传导中起作用。
    This work describes a novel route for phospholipid fatty acid remodeling involving the monounsaturated fatty acid palmitoleic acid. When administered to human monocytes, palmitoleic acid rapidly incorporates into membrane phospholipids, notably into phosphatidylcholine (PC). In resting cells, palmitoleic acid remains within the phospholipid pools where it was initially incorporated, showing no further movement. However, stimulation of the human monocytes with either receptor-directed (opsonized zymosan) or soluble (calcium ionophore A23187) agonists results in the rapid transfer of palmitoleic acid moieties from PC to phosphatidylinositol (PI). This is due to the activation of a coenzyme A-dependent remodeling route involving two different phospholipase A2 enzymes that act on different substrates to generate free palmitoleic acid and lysoPI acceptors. The stimulated enrichment of specific PI molecular species with palmitoleic acid unveils a hitherto-unrecognized pathway for lipid turnover in human monocytes which may play a role in regulating lipid signaling during innate immune activation.
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  • 文章类型: Journal Article
    背景:超重,通常被称为肥胖症,是脂肪的异常和过度积累,通过增加他们可能经历许多慢性疾病的可能性来暴露处于危险中的人的健康。因此,肥胖已成为全球健康威胁,带来严重的健康问题,并在医疗保健行业和科学界引起了很多关注。
    方法:本研究旨在探索7-MEGA™的抗脂肪生成特性,以试图解决肥胖问题,使用体外和体内研究。在给予高脂肪饮食(HFD)和3T3-L1脂肪细胞的肥胖小鼠中研究了三种不同浓度的7MEGA™的作用。
    结果:7MEGA™降低了总脂肪量,整体体重,HFD小鼠肾周和皮下白色脂肪组织(PWAT和SWAT)含量。此外,7MEGA™在改善肥胖个体的代谢健康和调节胰岛素激素水平方面显示出希望,促炎细胞因子和脂肪因子。此外,过氧化物酶体增殖物激活受体(PPAR)α和γ,解偶联蛋白1(UCP-1),甾醇调节元件结合蛋白1(SREBP-1),脂肪酸结合蛋白4(FABP4),脂肪酸合成酶(FAS),乙酰辅酶A羧化酶(ACC),硬脂酰辅酶A去饱和酶-1(SCD-1)和CCAAT/增强子结合蛋白(C/EBPα)是7MEGA™可以调节的脂肪生成调节因子。
    结论:总之,这项研究发现7MEGA™具有抗脂肪生成和抗肥胖作用,表明它在对抗肥胖方面的潜力。
    BACKGROUND: Overweight, often known as obesity, is the abnormal and excessive accumulation of fat that exposes the health of a person at risk by increasing the likelihood that they may experience many chronic conditions. Consequently, obesity has become a global health threat, presenting serious health issues, and attracting a lot of attention in the healthcare profession and the scientific community.
    METHODS: This study aims to explore the anti-adipogenic properties of 7-MEGA™ in an attempt to address obesity, using both in vitro and in vivo research. The effects of 7MEGA™ at three distinct concentrations were investigated in obese mice who were given a high-fat diet (HFD) and 3T3-L1 adipocytes.
    RESULTS: 7MEGA™ decreased the total fat mass, overall body weight, and the perirenal and subcutaneous white adipose tissue (PWAT and SWAT) contents in HFD mice. Additionally, 7MEGA™ showed promise in improving the metabolic health of individuals with obesity and regulate the levels of insulin hormone, pro-inflammatory cytokines and adipokines. Furthermore, Peroxisome proliferator-activated receptors (PPAR) α and γ, Uncoupling Protein 1 (UCP-1), Sterol Regulatory Element-Binding Protein 1 (SREBP-1), Fatty Acid-Binding Protein 4 (FABP4), Fatty Acid Synthase (FAS), Acetyl-CoA Carboxylase (ACC), Stearoyl-CoA Desaturase-1 (SCD-1) and CCAAT/Enhancer-Binding Protein (C/EBPα) were among the adipogenic regulators that 7MEGA™ could regulate.
    CONCLUSIONS: In summary, this study uncovered that 7MEGA™ demonstrates anti-adipogenic and anti-obesity effects, suggesting its potential in combating obesity.
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  • 文章类型: Journal Article
    沙棘果肉油(SBO)由于其丰富的亲脂性物质具有高的营养和药妆潜力而用于美容产品。然而,SBO增强皮肤弹性的机制尚不清楚。因此,在这项研究中,我们研究了在紫外线(UV)照射下,SBO在正常人真皮成纤维细胞(NHDF)中的抗光老化活性。SBO预处理显著抑制UV-B诱导的细胞毒性和胶原降解,表明SBO含有抗光老化物质。Further,棕榈油酸(POA),SBO的主要组成部分,通过抑制基质金属蛋白酶1(MMP-1)的表达来维持UV-B照射的NHDF中的细胞活力和胶原蛋白水平,并抑制p38和JNK磷酸化以及核因子-κB(NF-κB)的核转位。这些发现表明SBO作为抗光老化剂的实用性。
    Seabuckthorn pulp oil (SBO) is used in beauty products because of its rich lipophilic substances with high nutraceutical and cosmeceutical potential. However, the mechanism through which SBO enhances skin elasticity remains unclear. Therefore, in this study, we examined the anti-photoaging activity of SBO in normal human dermal fibroblasts (NHDF) under ultraviolet (UV) irradiation. Pretreatment with SBO significantly suppressed UV-B-induced cell toxicity and collagen degradation, suggesting that SBO contains anti-photoaging substances. Further, palmitoleic acid, the main component of SBO, maintained cell viability and collagen levels in UV-B-irradiated NHDF by suppressing the expression of matrix metalloproteinase 1 and acted on the inhibition of p38 and JNK phosphorylation and nuclear translocation of nuclear factor-kappa B. These findings suggest the utility of SBO as an anti-photoaging agent.
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  • 文章类型: Journal Article
    方法:棕榈油酸(POA)是一种ω-7单不饱和脂肪酸,已被建议用于改善代谢紊乱。然而,目前尚不清楚肠道菌群是否在POA改善代谢紊乱中发挥作用.本研究旨在探讨POA对代谢的调控,以及从血清代谢组和肠道微生物组的角度喂养HFD小鼠的全身性炎症。
    结果:将36只C57BL/6雄性小鼠随机分配到含有1.9%w/w猪油的正常饮食或含有20.68%w/w猪油或20.68%w/w沙棘果肉油的HFD中16周。研究发现POA能显著缓解高脂血症,胰岛素抵抗,和HFD喂养小鼠的炎症。补充POA会显著改变血清代谢物的组成,特别是甘油磷脂代谢途径中的脂质代谢产物。POA明显增加了双歧杆菌的丰度,降低了Allobaculum的丰度。重要的是,研究发现,甘油磷酸胆碱介导双歧杆菌对LDL-C的作用,鞘磷脂介导双歧杆菌对IL-6的作用,山楂酸介导Allobaculum对IL-6的作用。
    结论:结果表明,外源性POA可以改善HFD小鼠的代谢紊乱和炎症,可能通过调节血清代谢组和肠道微生物组。
    METHODS: Palmitoleic acid (POA) is an omega-7 monounsaturated fatty acid that has been suggested to improve metabolic disorders. However, it remains unclear whether gut microbiota plays a role in the amelioration of metabolic disorders by POA. This study aims to investigate the regulation of POA on metabolism, as well as systemic inflammation in HFD-fed mice from the perspective of serum metabolome and gut microbiome.
    RESULTS: Thirty-six C57BL/6 male mice are randomly assigned to either a normal chow diet containing 1.9% w/w lard or an HFD containing 20.68% w/w lard or 20.68% w/w sea buckthorn pulp oil for 16 weeks. The study finds that POA significantly attenuated hyperlipidemia, insulin resistance, and inflammation in HFD-fed mice. POA supplementation significantly alters the composition of serum metabolites, particularly lipid metabolites in the glycerophospholipid metabolism pathway. POA obviously increases the abundance of Bifidobacterium and decreases the abundance of Allobaculum. Importantly, the study finds that glycerophosphocholine mediates the effect of Bifidobacterium on LDL-C, sphingomyelin mediates the effect of Bifidobacterium on IL-6, and maslinic acid mediates the effect of Allobaculum on IL-6.
    CONCLUSIONS: The results suggest that exogenous POA can improve metabolic disorders and inflammation in HFD-fed mice, potentially by modulating the serum metabolome and gut microbiome.
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  • 文章类型: Clinical Trial Protocol
    棕榈油酸(POA),一个不必要的,单不饱和ω-7脂肪酸(C16:1n7),是一种从脂肪组织分泌的脂类激素,对远处的器官有有益的作用,比如肝脏和肌肉。有趣的是,POA减少了肝脏和肌肉等有毒储存部位的脂肪生成,矛盾的是,在安全的储存地点增加了脂肪生成,如脂肪组织。此外,人类较高的POA水平与更好的胰岛素敏感性相关,改善的血脂分布,2型糖尿病和心血管疾病的发病率较低,如心肌梗塞。在临床前动物模型中,POA改善葡萄糖不耐受,血脂异常,肌肉和肝脏的脂肪变性,同时改善胰岛素敏感性和分泌。这项双盲安慰剂对照临床试验检验了以下假设:POA可增加超重和肥胖成年糖尿病前期受试者的胰岛素敏感性并降低肝脏脂肪生成。重要的是要注意,这是首次使用纯(>90%)POA和<0.3%棕榈酸(PA)的研究,这掩盖了POA的有益效果。可能的阳性发现可以提供针对糖尿病和相关免疫代谢疾病的治疗和/或预防途径。
    Palmitoleic acid (POA), a nonessential, monounsaturated omega-7 fatty acid (C16:1n7), is a lipid hormone secreted from adipose tissue and has beneficial effects on distant organs, such as the liver and muscle. Interestingly, POA decreases lipogenesis in toxic storage sites such as the liver and muscle, and paradoxically increases lipogenesis in safe storage sites, such as adipose tissue. Furthermore, higher POA levels in humans are correlated with better insulin sensitivity, an improved lipid profile, and a lower incidence of type-2 diabetes and cardiovascular pathologies, such as myocardial infarction. In preclinical animal models, POA improves glucose intolerance, dyslipidemia, and steatosis of the muscle and liver, while improving insulin sensitivity and secretion. This double-blind placebo-controlled clinical trial tests the hypothesis that POA increases insulin sensitivity and decreases hepatic lipogenesis in overweight and obese adult subjects with pre-diabetes. Important to note, that this is the first study ever to use pure (>90%) POA with < 0.3% palmitic acid (PA), which masks the beneficial effects of POA. The possible positive findings may offer a therapeutic and/or preventative pathway against diabetes and related immunometabolic diseases.
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  • 文章类型: Journal Article
    <b>背景和目标:</b>棕榈油的双重需求,作为食用油和生物柴油的原料,引起人们对潜在短缺的担忧。因此,探索食用油的替代来源至关重要,其中一种选择是从西米毛虫中提取的油。本研究旨在提取和确定西米毛虫油的特性及其作为食用油的潜力。<b>材料与方法:</b>用压榨法提取西米毛毛虫油,索氏提取和Folch脂质提取。通过压榨获得的西米毛虫油的产量,索氏和Folch的脂质提取率分别为20%、16%和2.2%,分别。使用脱胶进行油净化,中和和漂白。此外,由此产生的西米毛毛虫油具有物理特征,化学和感官。<b>结果:</b>西米毛虫油符合根据印度尼西亚国家标准的食用油和其他化学参数作为食用油的要求。用气相色谱-质谱联用仪分析西米毛虫油的结果表明,西米毛虫油含有0.15%的月桂酸,2.06%肉豆蔻酸,5.92%棕榈油酸,55.05%棕榈酸,0.84%亚油酸,34.00%油酸和1.43%硬脂酸。傅里叶变换红外分光光度计的主峰位置为725、1118、1165、1234、1373、1458、1743、2854和2924cm<sup>1</sup>。对西米毛虫油的分析结果表明,西米毛虫油的脂质分布与商品棕榈油相似。<b>结论:</b>根据提取结果,纯化和表征,结论是西米毛毛虫油具有用作食用油的潜力。
    <b>Background and Objective:</b> The dual demand for palm oil, both as a cooking oil and as a raw material for biodiesel, gives rise to concerns regarding potential shortages. Hence, it is crucial to explore alternative sources of cooking oil, with one such alternative being the oil extracted from sago caterpillars. This study aims to extract and determine the characteristics of sago caterpillar oil and its potential as cooking oil. <b>Materials and Methods:</b> Sago caterpillar oil extraction was done using pressing, Soxhlet extraction and Folch\'s lipid extraction. The yield of sago caterpillar oil obtained by pressing, Soxhlet and Folch\'s lipid extraction were 20, 16 and 2.2%, respectively. Oil purifying was done using degumming, neutralization and bleaching. Furthermore, the resulting sago caterpillar oil was characterized physically, chemically and organoleptic. <b>Results:</b> The sago caterpillar oil met the requirements as cooking oil based on the Indonesian National Standard for cooking oil and other chemical parameters. The results of the analysis of sago caterpillar oil with gas chromatography-mass spectrometer showed that the sago caterpillar oil contained 0.15% lauric acid, 2.06% myristic acid, 5.92% palmitoleic acid, 55.05% palmitic acid, 0.84% linoleic acid, 34.00% oleic acid and 1.43% stearic acid. The main peak positions from the fourier transform infrared spectrophotometer are at 725, 1118, 1165, 1234, 1373, 1458, 1743, 2854 and 2924 cm<sup>1</sup>. The results of the analysis of sago caterpillar oil showed that the lipid profile of sago caterpillar oil was similar to commercial palm oil. <b>Conclusion:</b> Based on the results of extraction, purifying and characterization, it was concluded that sago caterpillar oil has the potential to be used as cooking oil.
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  • 文章类型: Journal Article
    脂肪酸已经提供给不同的非食品,从植物油和动物脂肪的工业应用几十年。由于世界人口大量增加,需要营养饮食,并且以可持续的方式为工业生产线提供原料,即,独立于食品供应链,替代脂肪酸来源已经获得了大量的重要性。富含碳水化合物的农业生产侧流,例如,糖蜜,木质纤维素废物,来自生物柴油生产的甘油,甚至CO2都被认为并用作碳源,用于在选定的微生物宿主中发酵积累脂肪酸。虽然某些脂肪酸很容易在天然微生物代谢途径中积累,其他脂肪酸种类很少,和宿主菌株需要进行代谢改造以实现高水平生产。我们报道了巴斯德毕赤酵母从葡萄糖生产棕榈油酸的代谢工程,并详细讨论了有益和有害的工程步骤。脂肪酸分泌是通过脂酰辅酶A合成酶的缺失和截短的大肠杆菌硫酯酶TesA的过表达实现的。最佳菌株向培养基中分泌>1g/L的游离脂肪酸。此外,引入C16特异性Δ9-去饱和酶和脂肪酸合酶,加上栽培条件的改善,棕榈油酸含量从5.5%增加到22%。
    Fatty acids have been supplied for diverse non-food, industrial applications from plant oils and animal fats for many decades. Due to the massively increasing world population demanding a nutritious diet and the thrive to provide feedstocks for industrial production lines in a sustainable way, i.e., independent from food supply chains, alternative fatty acid sources have massively gained in importance. Carbohydrate-rich side-streams of agricultural production, e.g., molasses, lignocellulosic waste, glycerol from biodiesel production, and even CO2, are considered and employed as carbon sources for the fermentative accumulation of fatty acids in selected microbial hosts. While certain fatty acid species are readily accumulated in native microbial metabolic routes, other fatty acid species are scarce, and host strains need to be metabolically engineered for their high-level production. We report the metabolic engineering of Pichia pastoris to produce palmitoleic acid from glucose and discuss the beneficial and detrimental engineering steps in detail. Fatty acid secretion was achieved through the deletion of fatty acyl-CoA synthetases and overexpression of the truncated E. coli thioesterase \'TesA. The best strains secreted >1 g/L free fatty acids into the culture medium. Additionally, the introduction of C16-specific ∆9-desaturases and fatty acid synthases, coupled with improved cultivation conditions, increased the palmitoleic acid content from 5.5% to 22%.
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  • 文章类型: Journal Article
    据报道棕榈油酸(ω-7)主要对代谢紊乱有效。最近,据报道,它可以通过改善皮肤症状来帮助改善生活质量(QoL)。
    这项随机研究的目的是,双盲,安慰剂对照临床研究旨在评价口服棕榈油酸改善皮肤屏障的有效性和安全性,弹性,和成年女性的皱纹形成。
    在这个随机的,双盲,安慰剂对照临床研究,纳入90名健康参与者,接受500毫克/天的棕榈油酸(干预)或不含棕榈油酸的玉米油(对照),持续12周。皮肤水合和经表皮水分流失和皮肤弹性,表面粗糙度,眼睛皱纹体积,每隔6周测量一次皱纹严重程度,以评估皮肤屏障功能和改善皱纹的功效,分别。
    12周后,与对照组相比,干预组的皮肤水合作用和经表皮水分流失显着改善。皮肤弹性,表面粗糙度,眼睛皱纹体积,皱纹严重程度,参与者评估的临床改善评分与对照组相比没有显著改善.
    口服棕榈油酸有效改善皮肤屏障功能,这可能会提高老年人的QoL。
    UNASSIGNED: Palmitoleic acid (omega-7) has been reported to be effective primarily for metabolic disorders. Recently, it has been reported to help improve quality of life (QoL) by improving skin symptoms.
    UNASSIGNED: The aim of this randomized, double-blinded, placebo-controlled clinical study is to evaluate the efficacy and safety of oral palmitoleic acid in improving skin barrier, elasticity, and wrinkle formation in adult women.
    UNASSIGNED: In this randomized, double-blind, placebo-controlled clinical study, 90 healthy participants were enrolled and received 500 mg/day palmitoleic acid (intervention) or corn oil without palmitoleic acid (control) for 12 weeks. Skin hydration and transepidermal water loss and skin elasticity, surface roughness, eye wrinkle volume, and wrinkle severity were measured at 6-week intervals to assess the skin barrier function and efficacy in wrinkle improvement, respectively.
    UNASSIGNED: After 12 weeks, skin hydration and transepidermal water loss significantly improved in the intervention group compared to the control group. Skin elasticity, surface roughness, eye wrinkle volume, wrinkle severity, and participant-assessed clinical improvement score did not significantly improve compared with the control group.
    UNASSIGNED: Oral palmitoleic acid effectively improves the skin barrier function improvement, which may enhance QoL in aging adults.
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  • 文章类型: Journal Article
    着眼于两种I型脂肪酸合酶FasA和FasB的催化性能的差异,fasA基因在产生油酸的谷氨酸棒杆菌菌株中被破坏。所得的脂肪酸合成仅依赖于FasB的需要油酸的菌株在补充有最低浓度的油酸钠用于生长的条件下显示出从1%葡萄糖几乎独家产生(217mg/L)的棕榈酸(C16:0)。质粒介导的fasB扩增导致棕榈酸产量增加1.47倍(320mg/L),而fasB破坏导致没有脂肪酸产生,分泌丙二酸(30mg/L)。接下来,旨在将棕榈酸生产商转化为棕榈油酸生产商(POA,C16:1Δ9),我们将硝基还原假单胞菌Δ9去饱和酶基因desBC引入了棕榈酸生产者。虽然这导致了失败,我们注意到出现了显示不需要油酸表型的抑制突变体.生产实验表明,一个这样的突变体M-1无疑产生POA(17mg/L)和棕榈酸(173mg/L)。全基因组分析和随后的遗传分析确定菌株M-1的抑制突变为DtxtR蛋白的功能丧失突变,全球铁代谢调控者.考虑到DesBC都是含铁的酶,我们研究了增加铁利用率以改善棕榈酸与POA的DesBC依赖性转化率的条件。最终,在工程菌株中补充血红素和铁螯合剂原儿茶酸可将POA的产量显着提高至161mg/L,转化率为80.1%。细胞脂肪酸分析显示,产生POA的细胞确实配备了主要由棕榈酸(占总细胞脂肪酸的85.1%)组成的非天然膜脂质,其次是非天然POA(12.4%)。
    Focusing on the differences in the catalytic properties of two type I fatty acid synthases FasA and FasB, the fasA gene was disrupted in an oleic acid-producing Corynebacterium glutamicum strain. The resulting oleic acid-requiring strain whose fatty acid synthesis depends only on FasB exhibited almost exclusive production (217 mg/L) of palmitic acid (C16:0) from 1% glucose under the conditions supplemented with the minimum concentration of sodium oleate for growth. Plasmid-mediated amplification of fasB led to a 1.47-fold increase in palmitic acid production (320 mg/L), while fasB disruption resulted in no fatty acid production, with excretion of malonic acid (30 mg/L). Next, aiming at conversion of the palmitic acid producer to a producer of palmitoleic acid (POA, C16:1Δ9), we introduced the Pseudomonas nitroreducens Δ9-desaturase genes desBC into the palmitic acid producer. Although this resulted in failure, we noticed the emergence of suppressor mutants that exhibited the oleic acid-non-requiring phenotype. Production experiments revealed that one such mutant M-1 undoubtedly produced POA (17 mg/L) together with palmitic acid (173 mg/L). Whole genomic analysis and subsequent genetic analysis identified the suppressor mutation of strain M-1 as a loss-of-function mutation for the DtxR protein, a global regulator of iron metabolism. Considering that DesBC are both iron-containing enzymes, we investigated the conditions for increased iron availability to improve the DesBC-dependent conversion ratio of palmitic acid to POA. Eventually, supplementation of both hemin and the iron chelator protocatechuic acid in the engineered strain dramatically enhanced POA production to 161 mg/L with a conversion ratio of 80.1%. Cellular fatty acid analysis revealed that the POA-producing cells were really equipped with unnatural membrane lipids comprised predominantly of palmitic acid (85.1% of total cellular fatty acids), followed by non-native POA (12.4%).
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