BACKGROUND & AIMS: :With recent advances in synthetic biology, CO2 could be utilized as a carbon feedstock by native or engineered organisms, assuming the availability of electrons. Two key enzymes used in autotrophic CO2 fixation are the CO dehydrogenase (CODH) and acetyl coenzyme A (acetyl-CoA) synthase (ACS), which form a bifunctional heterotetrameric complex. The CODH/ACS complex can reversibly catalyze CO2 to CO, effectively enabling a biological water-gas shift reaction at ambient temperatures and pressures. The CODH/ACS complex is part of the Wood-Ljungdahl pathway (WLP) used by acetogens to fix CO2, and it has been well characterized in native hosts. So far, only a few recombinant CODH/ACS complexes have been expressed in heterologous hosts, none of which demonstrated in vivo CO2 reduction. Here, functional expression of the Clostridium carboxidivorans CODH/ACS complex is demonstrated in the solventogen Clostridium acetobutylicum, which was engineered to express CODH alone or together with the ACS. Both strains exhibited CO2 reduction and CO oxidation activities. The CODH reactions were interrogated using isotopic labeling, thus verifying that CO was a direct product of CO2 reduction, and vice versa. CODH apparently uses a native C. acetobutylicum ferredoxin as an electron carrier for CO2 reduction. Heterologous CODH activity depended on actively growing cells and required the addition of nickel, which is inserted into CODH without the need to express the native Ni insertase protein. Increasing CO concentrations in the gas phase inhibited CODH activity and altered the metabolite profile of the CODH-expressing cells. This work provides the foundation for engineering a complete and functional WLP in nonnative host organisms.IMPORTANCE Functional expression of CO dehydrogenase (CODH) from Clostridium carboxidivorans was demonstrated in C. acetobutylicum, which is natively incapable of CO2 fixation. The expression of CODH, alone or together with the C. carboxidivorans acetyl-CoA synthase (ACS), enabled C. acetobutylicum to catalyze both CO2 reduction and CO oxidation. Importantly, CODH exhibited activity in both the presence and absence of ACS. 13C-tracer studies confirmed that the engineered C. acetobutylicum strains can reduce CO2 to CO and oxidize CO during growth on glucose.

背景与目标： ：随着合成生物学的最新进展，假设电子的可用性，CO2可以被天然或工程有机体用作碳原料。自养二氧化碳固定中使用的两个关键酶是CO脱氢酶（CODH）和乙酰辅酶A（乙酰-CoA）合酶（ACS），它们形成了双功能异四聚体复合物。 CODH / ACS复合物可以可逆地将CO2催化转化为CO，从而有效地实现了在环境温度和压力下进行生物水煤气变换反应。 CODH / ACS复合物是乙酸原用于固定CO2的Wood-Ljungdahl途径（WLP）的一部分，在天然宿主中已得到很好的表征。迄今为止，在异源宿主中仅表达了少数重组CODH / ACS复合物，但均未显示体内CO2减少。在此，在溶剂原丙酮丁醇梭菌（Clostridium acetobutylicum）中证明了碳氧化梭菌CODH / ACS复合物的功能性表达，该溶剂被改造成单独或与ACS一起表达CODH。两种菌株均表现出CO 2还原和CO氧化活性。使用同位素标记对CODH反应进行了询问，从而验证了CO是CO2还原的直接产物，反之亦然。 CODH显然使用天然的丙酮丁醇梭菌铁氧还蛋白作为电子载体来减少CO2。异源CODH活性取决于活跃生长的细胞，并需要添加镍，而无需表达天然Ni插入酶蛋白即可将其插入CODH。气相中CO浓度的增加会抑制CODH活性并改变表达CODH的细胞的代谢产物谱。这项工作为在非天然宿主生物中工程化完整且功能性的WLP提供了基础。重要提示丙酮丁醇梭菌（C. acettobutylicum）表现出了羧甲基梭菌（Clostridium carboxidivorans）的CO脱氢酶（CODH）的功能性表达，而这本来就无法固定CO2。 CODH的表达，单独或与碳氧化单胞菌乙酰辅酶A合酶（ACS）一起表达，可使丙酮丁醇梭菌既催化CO2还原又催化CO氧化。重要的是，在有或没有ACS的情况下，CODH均表现出活性。 13C示踪剂研究证实，工程改造的丙酮丁醇梭菌菌株可以在葡萄糖生长期间将CO2还原为CO，并氧化CO。

BACKGROUND & AIMS: :In the isolated rat heart perfused with glucose as substrate, measurements were made of perfusate and tissue lactate and pyruvate concentrations, and of tissue α-glycerophosphate and dihydroxyacetone phosphate concentrations. The conditions studied included increased heart work, anoxia, the addition of insulin, acute alloxan diabetes, chronic streptozotocin diabetes, and the addition of ketone bodies. True intracellular lactate values (estimated from the lactate and sorbitol spaces) and apparent tissue values exceeded perfusate values, showing the existence of a lactate concentration gradient. During anoxia, the lactate gradient diminished. Cytoplasmic free NAD+/NADH ratios calculated from the extracellular lactate/pyruvate ratio were similar to and changed in the same direction as the NAD+/NADH ratios calculated from the tissue α-glycerophosphate/dihydroxyacetone phosphate ratios in non-diabetic hearts. In diabetio hearts, extracellular and tissue lactate/pyruvate ratios gave different values for the cytoplasmic free NAD+/NADH ratios than did tissue α-glycero-phoaphate/dihydroxyacetone phosphate ratios. These discrepancies were associated with accumulation of pyruvate in the perfusate and the tissue. Changes in the extracellular lactate/pyruvate ratio gave a better differentiation between acute heart work and acute anoxia than did changes in the heart lactate/pyruvate ratio. The use of extracellular lactate/ pyruvate measurements in assessing the state of myocardial oxygenation is supported by these observations, provided that nutritional factors are taken into account and the diabetic state is excluded.

背景与目标： ：在以葡萄糖为底物灌注的离体大鼠心脏中，测量灌注液，组织乳酸和丙酮酸的浓度，以及组织α-甘油磷酸和二羟基丙酮磷酸的浓度。研究的疾病包括心脏工作增加，缺氧，胰岛素的添加，急性四氧嘧啶糖尿病，慢性链脲佐菌素糖尿病和酮体的添加。真实的细胞内乳酸值（从乳酸和山梨糖醇空间估算）和表观组织值超过灌注液值，表明存在乳酸浓度梯度。在缺氧期间，乳酸梯度降低。由细胞外乳酸盐/丙酮酸盐比率计算出的细胞质游离NAD / NADH比率与在非糖尿病性心脏中由组织α-甘油磷酸酯/二羟基丙酮磷酸盐比率计算出的NAD / NADH比率相似并且在相同的方向上改变。在糖尿病心脏中，细胞外和组织中乳酸/丙酮酸的比率与组织α-甘油-磷酸盐/二羟基丙酮磷酸盐的比率给出的细胞质游离NAD / NADH比率值不同。这些差异与丙酮酸在灌注液和组织中的积累有关。细胞外乳酸/丙酮酸比的变化比心脏乳酸/丙酮酸比的变化更好地区分了急性心脏功和急性缺氧。这些观察结果支持在评估心肌氧合状态时使用细胞外乳酸/丙酮酸的测量结果，但要考虑到营养因素并且排除糖尿病状态。

BACKGROUND & AIMS: The oxidized and semiquinone anion radical forms of flavin mononucleotide carried by flavocytochrome b2 and L-lactate monooxygenase have been studied by resonance Raman (RR) spectroscopy. The RR spectra of their oxidized forms are compared with previously published RR data on various flavins and flavoproteins. Taking as a support available X-ray crystallographic data on flavoproteins, we have found correlations between the frequencies of RR bands II (1575-1588 cm-1), III (1534-1557 cm-1), and X (1244-1266 cm-1) and the H-bonding environment and/or the structure of the flavin ring. The present RR data provide strong evidence that the electron density, the conformation, and the H-bonding environment of the oxidized flavin mononucleotide of flavocytochrome b2 and L-lactate monooxygenase are different. As far as the anionic semiquinone form of flavoproteins is concerned, the behavior of two bands observed at 1280-1300 and 1320-1350 cm-1 suggests that they have vibrational origins similar to those of RR bands II and III of oxidized compounds. On this basis, the differences in conformation and H-bonding environment of the isoalloxazine ring, observed for the oxidized form of flavocytochrome b2 and L-lactate monooxygenase, appear to be preserved upon one-electron reduction of the flavin. For both flavoproteins, the RR spectra of the semiquinone form are affected by pyruvate binding. The data are interpreted in the frame of a change in H-bonding interaction of the C4&dbd;O carbonyl group of the flavin without significant alteration of the isoalloxazine conformation. This modification in electrostatic interaction quantitatively accounts for the pyruvate-induced changes of the oxidized/semiquinone and semiquinone/reduced redox potentials of the flavoproteins. Considering the high homology in the flavin catalytic sites of flavocytochrome b2 and L-lactate monooxygenase, the observed differences in H-bonding environment and conformation of the FMN ring are related to the different biological functions of the two flavoproteins.

背景与目标： 通过共振拉曼光谱研究了黄素细胞色素b2和L-乳酸单加氧酶携带的黄素单核苷酸的氧化和半醌阴离子自由基形式。将其氧化形式的RR光谱与先前发表的有关各种黄素和黄素蛋白的RR数据进行比较。作为对黄素蛋白的可用X射线晶体学数据的支持，我们发现RR波段II（1575-1588 cm-1），III（1534-1557 cm-1）和X（1244-1266 cm）的频率之间存在相关性-1）和H键合环境和/或黄素环的结构。目前的RR数据提供了有力的证据，证明黄素细胞色素b2和L-乳酸单加氧酶的氧化黄素单核苷酸的电子密度，构象和H键环境不同。就黄素蛋白的阴离子半醌形式而言，在1280-1300和1320-1350 cm-1处观察到的两个谱带的行为表明，它们的振动起源与氧化化合物的RR谱带II和III相似。在此基础上，对黄素细胞色素b2和L-乳酸单加氧酶的氧化形式观察到的异恶嗪环的构象和H键环境的差异似乎在黄素的单电子还原中得以保留。对于两种黄素蛋白，丙酮酸结合都会影响半醌形式的RR光谱。在黄素的C 4 -O羰基的H键相互作用变化的框架内解释了数据，而异四恶嗪构象没有显着改变。静电相互作用的这种改变定量地解释了黄酮蛋白的丙酮酸诱导的氧化/半醌和半醌/还原的氧化还原电势的变化。考虑到黄素细胞色素b2和L-乳酸单加氧酶在黄素催化位点上的高度同源性，观察到的H键环境和FMN环构象的差异与两种黄素蛋白的不同生物学功能有关。

BACKGROUND & AIMS: BACKGROUND:The IDH1 gene, which encodes isocitrate dehydrogenase 1, is frequently mutated in gliomas and acute myeloid leukemia. The single-nucleotide polymorphism (SNP) (reference SNP no. rs11554137:C>T) located on IDH1 codon 105 has been associated with a poor outcome in patients with acute myeloid leukemia but has not been investigated in patients with gliomas. METHODS:The IDH1 codon 105 SNP was genotyped first in a series of 952 patients with grade 2 through 4 gliomas and was correlated with outcomes and tumor genomic profile. Then, it was genotyped in 2 validations sets of 306 patients with glioblastoma (GBM) and 591 patients with glioma. RESULTS:The minor allele codon 105 glycine (GGT) SNP (IDH1(105GGT) ) was identified in 98 of 952 patients (10.3%) and was not associated with the codon 132 (IDH1(132) ) mutation. Patients who had GMB with the IDH1(105GGT) variant had a poorer outcome than patients without the variant (median overall survival [OS], 10.7 months vs 15.5 months; P = .001; median progression-free survival [PFS], 6.4 months vs 8.5 months; P = .003). The prognostic impact was confirmed in an independent validation set of 306 GBMs from the same center (median PFS, 6.8 months vs 9.7 months; P = .006; median OS, 13.9 months vs 18.8 months; P = .0187). In the second validation cohort (591 grade 2-4 gliomas), a significant association was observed between IDH1(105GGT) and an adverse prognosis for the overall series and for patients with World Health Organization grade 3 gliomas, but the difference did not reach significance in patients with GBM. CONCLUSIONS:Taken together, the current data strongly suggested an association between the SNP rs11554137:C>T polymorphism and adverse outcomes in patients with malignant glioma. A single-nucleotide polymorphism (SNP) located on codon 105 of the isocitrate dehydrogenase 1 (IDH1) gene (reference SNP rs11554137) is analyzed in 3 independent series of patients with gliomas. The SNP rs11554137 is independent of the occurrence of somatic mutation on IDH1 codon 132, but, per se, has a prognostic impact in malignant gliomas.

背景与目标： 背景：编码异柠檬酸脱氢酶1的IDH1基因在神经胶质瘤和急性髓细胞性白血病中经常发生突变。位于IDH1密码子105上的单核苷酸多态性（SNP）（参考SNP号rs11554137：C> T）与急性髓细胞性白血病患者的不良预后相关，但尚未在神经胶质瘤患者中进行过研究。
方法：IDH1密码子105 SNP首先在一系列952例2至4级神经胶质瘤患者中进行基因分型，并与预后和肿瘤基因组特征相关。然后，在306例胶质母细胞瘤（GBM）患者和591例胶质瘤患者的2个验证组中对其进行了基因分型。
结果：在952名患者中的98名（10.3％）中鉴定出次要等位基因105甘氨酸（GGT）SNP（IDH1（105GGT）），与132号密码子（IDH1（132））突变无关。具有IDH1（105GGT）变体的GMB患者比没有该变体的患者的预后较差（中位总生存期[OS]为10.7个月vs 15.5个月； P = .001；中位无进展生存期[PFS]为6.4个月） vs 8.5个月； P = 0.003）。在来自同一中心的306个GBM的独立验证集中确认了预后影响（中位PFS，6.8个月对9.7个月； P = .006；中位OS，13.9个月对18.8个月； P = .0187）。在第二个验证队列（591个2-4级神经胶质瘤）中，观察到IDH1（105GGT）与整个系列以及世界卫生组织3级神经胶质瘤患者的不良预后之间存在显着相关性，但差异没有显着性在GBM患者中。
结论：综上所述，当前数据强烈表明SNP rs11554137：C> T多态性与恶性神经胶质瘤患者不良预后之间存在关联。在3个独立的神经胶质瘤患者系列中分析了位于异柠檬酸脱氢酶1（IDH1）基因（参考SNP rs11554137）密码子105上的单核苷酸多态性（SNP）。 SNP rs11554137与IDH1密码子132上体细胞突变的发生无关，但就其本身而言，对恶性神经胶质瘤具有预后影响。

BACKGROUND & AIMS: :Abstract Glucose has been found to impair the inhibition of platelets with aspirin and alter the basal activity of nitric oxide synthase (NOS) in platelets. The aim of this work was to study the effects of glucose on the inhibitory pathways in activated platelets. A short-term incubation of glucose impaired the inhibition of platelet aggregation induced by agents activating an NOS-dependent pathway, such as l-arginine, adenosine and α-tocopherol. However, glucose had no effect on the inhibition induced by iloprost and BW245C, agents that activate the cyclic adenosine monophosphate (cAMP) signaling pathway. Potassium lactate attenuated the effects of the same inhibitors as glucose did. The inhibitors of glucose transport prevented the effect of glucose. Dichloroacetate, known to prevent the conversion of pyruvate to lactate and to decrease lactate in platelets, significantly attenuated the effect of glucose in platelets. The data support the suggestion that the effect of glucose on the inhibition of platelets by agents activating an NOS-dependent pathway is mediated by glucose metabolite lactate.

背景与目标： 摘要：已发现葡萄糖会削弱阿司匹林对血小板的抑制作用，并改变血小板中一氧化氮合酶（NOS）的基础活性。这项工作的目的是研究葡萄糖对活化血小板抑制途径的影响。葡萄糖的短期温育削弱了由激活NOS依赖性途径的药物（如L-精氨酸，腺苷和α-生育酚）诱导的血小板凝集抑制作用。但是，葡萄糖对伊洛前列素和BW245C所诱导的抑制作用没有影响，伊洛前列素和BW245C可以激活环磷酸腺苷（cAMP）信号通路。乳酸钾减弱了与葡萄糖相同的抑制剂的作用。葡萄糖转运的抑制剂阻止了葡萄糖的作用。众所周知，二氯乙酸盐可防止丙酮酸转化为乳酸盐并减少血小板中的乳酸盐，从而大大减弱了葡萄糖在血小板中的作用。数据支持这样的建议，即葡萄糖对乳酸的影响是通过激活NOS依赖性途径的药物对血小板的抑制作用。

BACKGROUND & AIMS: :Human choline dehydrogenase (CHD) is located in the inner membrane of mitochondria primarily in liver and kidney and catalyzes the oxidation of choline to glycine betaine. Its physiological role is to regulate the concentrations of choline and glycine betaine in the blood and cells. Choline is important for regulation of gene expression, the biosynthesis of lipoproteins and membrane phospholipids and for the biosynthesis of the neurotransmitter acetylcholine; glycine betaine plays important roles as a primary intracellular osmoprotectant and as methyl donor for the biosynthesis of methionine from homocysteine, a required step for the synthesis of the ubiquitous methyl donor S-adenosyl methionine. Recently, CHD has generated considerable medical attention due to its association with various human pathologies, including male infertility, homocysteinuria, breast cancer and metabolic syndrome. Despite the renewed interest, the biochemical characterization of the enzyme has lagged behind due to difficulties in the obtainment of purified, active and stable enzyme. This review article summarizes the medical relevance and the physiological roles of human CHD, highlights the biochemical knowledge on the enzyme, and provides an analysis based on the comparison of the protein sequence with that of bacterial choline oxidase, for which structural and biochemical information is available.

背景与目标： 人胆碱脱氢酶（CHD）位于线粒体内膜中，主要位于肝脏和肾脏中，并催化胆碱氧化为甘氨酸甜菜碱。它的生理作用是调节血液和细胞中胆碱和甘氨酸甜菜碱的浓度。胆碱对调节基因表达，脂蛋​​白和膜磷脂的生物合成以及神经递质乙酰胆碱的生物合成很重要。甘氨酸甜菜碱起着重要的细胞内渗透保护剂的作用，并作为高半胱氨酸生物合成蛋氨酸的甲基供体，这是合成无处不在的甲基供体S-腺苷蛋氨酸的必需步骤。最近，由于冠心病与各种人类疾病相关，包括男性不育症，高半胱氨酸尿症，乳腺癌和代谢综合症，已经引起了广泛的医学关注。尽管重新获得了兴趣，但是由于难以获得纯化的，活性的和稳定的酶，所以该酶的生物化学表征已经落后。这篇综述文章总结了人类冠心病的医学相关性和生理作用，着重介绍了该酶的生化知识，并根据蛋白质序列与细菌胆碱氧化酶的序列比较进行了分析，从而获得了结构和生化信息。 。

BACKGROUND & AIMS: PURPOSE OF REVIEW:The conventional view in severe sepsis or septic shock is that most of the lactate that accumulates in the circulation is due to cellular hypoxia and the onset of anaerobic glycolysis. A number of papers have suggested that lactate formation during sepsis is not due to hypoxia. I discuss this hypothesis and outline the recent advances in the understanding of lactate metabolism in shock. RECENT FINDINGS:Numerous experimental data have demonstrated that stimulation of aerobic glycolysis - that is, glycolysis not attributable to oxygen deficiency - and glycogenolysis occurs not only in resting, well-oxygenated skeletal muscles but also during experimental haemorrhagic shock and experimental sepsis, and is closely linked to stimulation of sarcolemmal Na+/K+ -ATPase under epinephrine stimulation. A human study of hyperkinetic septic shock demonstrated that skeletal muscle is a leading source of lactate production by exaggerated aerobic glycolysis through Na+/K+ -ATPase stimulation. SUMMARY:There is increasing evidence that sepsis is accompanied by a hypermetabolic state, with enhanced glycolysis and hyperlactataemia. This should not be rigorously interpreted as an indication of hypoxia. It now appears, at least in the hyperkinetic state, that increased lactate production and concentration as a result of hypoxia are often the exception rather than the rule.

背景与目标： 审查的目的：严重败血症或败血性休克的传统观点是，循环中积累的大多数乳酸是由于细胞缺氧和厌氧糖酵解的开始所致。许多论文表明败血症期间乳酸的形成不是由于缺氧引起的。我讨论了这一假设，并概述了休克中乳酸代谢的最新研究进展。
最近的发现：大量的实验数据表明，有氧糖酵解的刺激-即不是由于缺氧引起的糖酵解-糖原分解不仅发生在静息的，充氧的骨骼肌中，而且还发生在实验性失血性休克和实验性败血症中，并且密切相关与肾上腺素刺激下肌膜Na / K -ATPase的刺激有关。一项针对运动过度性败血性休克的人体研究表明，骨骼肌是通过Na / K -ATPase刺激导致的过度有氧糖酵解产生乳酸的主要来源。
摘要：有越来越多的证据表明败血症伴有代谢亢进状态，并伴有糖酵解和高乳酸血症。不应将其严格解释为缺氧的征兆。现在看来，至少在运动亢进状态下，缺氧导致的乳酸产生和浓度增加通常是例外而不是规则。

BACKGROUND & AIMS: OBJECTIVE:The role of glucocorticoids production in adipose tissue in the development of metabolic disorders in humans has not been fully characterized. We investigated whether in obese subjects, 11beta-hydroxysteroid dehydrogenase type 1 (11beta-HSD1) expression in subcutaneous (SAT) and visceral (VAT) adipose tissue is associated with the occurrence of metabolic disorders and the expression of adiponectin and tumor necrosis factor alpha (TNFalpha) and two glucocorticoid-regulated adipokines able to influence the metabolic control. DESIGN AND SUBJECTS:Sixty-two obese patients were enrolled in the study. SAT and VAT samples were obtained from 13 patients undergoing bariatric surgery (body mass index (BMI) 39.1+/-5.3 kg/m(2)). SAT samples were obtained from 49 patients who underwent periumbilical biopsy (BMI 36.9+/-5.1 kg/m(2)). MEASUREMENTS:Oral glucose tolerance tests in subjects without known diabetes. Circulating glucose, lipid, insulin, adiponectin, TNFalpha and urinary-free cortisol levels. Real-time PCR to quantify mRNA levels of 11beta-HSD1, hexose-6-phosphate dehydrogenase (H6PDH), adiponectin and TNFalpha. Western blot analysis to evaluate 11beta-HSD1 protein expression. RESULTS:In the majority of the obese subjects, VAT expresses more 11beta-HSD1 than SAT. VAT 11beta-HSD1 expression was not associated with metabolic disorders. SAT 11beta-HSD1 mRNA levels were higher in subjects with than in those without metabolic syndrome (P<0.05) and in patients with type 2 diabetes compared to patients with impaired or normal glucose tolerance (P<0.0001). SAT 11beta-HSD1 expression was independently related to fasting glucose (P<0.0001) and urinary-free cortisol levels (P<0.01), and increased expression of 11beta-HSD1 was associated with increased adiponectin and TNFalpha expression and decreased serum adiponectin levels (all P's <0.05). CONCLUSIONS:In obese subjects, increased 11beta-HSD1 expression in SAT, but not in VAT, is associated with the worsening of metabolic conditions. We hypothesize that higher glucocorticoid production in adipose tissue would favor the development of metabolic disorders through a decrease in adiponectin release.

背景与目标： 目的：脂肪组织中糖皮质激素的产生在人类代谢性疾病发展中的作用尚未完全阐明。我们调查了在肥胖受试者中，皮下（SAT）和内脏（VAT）脂肪组织中的11beta-羟类固醇脱氢酶1型（11beta-HSD1）表达是否与代谢紊乱的发生以及脂联素和肿瘤坏死因子α（ TNFalpha）和两种糖皮质激素调节的脂肪因子能够影响代谢控制。
设计和受试者：62名肥胖患者参加了这项研究。 SAT和VAT样本是从13例减肥手术患者中获得的（体重指数（BMI）39.1 /-5.3 kg / m（2））。 SAT样本来自49位接受了脐周活检的患者（BMI 36.9 /-5.1 kg / m（2））。
测量：在没有已知糖尿病的受试者中进行口服葡萄糖耐量测试。循环中的葡萄糖，脂质，胰岛素，脂联素，TNFα和无尿皮质醇水平。实时PCR定量11beta-HSD1、6-磷酸己糖脱氢酶（H6PDH），脂联素和TNFalpha的mRNA水平。蛋白质印迹分析以评估11beta-HSD1蛋白表达。
结果：在大多数肥胖受试者中，VAT比SAT表达更多的11beta-HSD1。 VAT 11beta-HSD1表达与代谢异常无关。与糖耐量减低或正常的患者相比，有糖代谢的患者的SAT 11beta-HSD1 mRNA水平高于无代谢综合症的患者（P <0.05）和患有2型糖尿病的患者（P <0.0001）。 SAT 11beta-HSD1表达与空腹血糖（P <0.0001）和无尿皮质醇水平（P <0.01）独立相关，而11beta-HSD1表达增加与脂联素和TNFalpha表达增加以及血清脂联素水平降低相关（所有P ＜0.05）。
结论：在肥胖的受试者中，SAT中11beta-HSD1表达增加，而VAT中没有，与代谢状况的恶化有关。我们假设脂肪组织中较高的糖皮质激素产生将通过减少脂联素的释放而促进代谢紊乱的发展。

BACKGROUND & AIMS: :A specific chorion peroxidase is present in Aedes aegypti and this enzyme is responsible for catalyzing chorion protein cross-linking through dityrosine formation during chorion hardening. Peroxidase-mediated dityrosine cross-linking requires H(2)O(2), and this study discusses the possible involvement of the chorion peroxidase in H(2)O(2) formation by mediating NADH/O(2) oxidoreduction during chorion hardening in A. aegypti eggs. Our data show that mosquito chorion peroxidase is able to catalyze pH-dependent NADH oxidation, which is enhanced in the presence of Mn(2+). Molecular oxygen is the electron acceptor during peroxidase-catalyzed NADH oxidation, and reduction of O(2) leads to the production of H(2)O(2), demonstrated by the formation of dityrosine in a NADH/peroxidase reaction mixture following addition of tyrosine. An oxidoreductase capable of catalyzing malate/NAD(+) oxidoreduction is also present in the egg chorion of A. aegypti. The cooperative roles of chorion malate/NAD(+)oxidoreductase and chorion peroxidase on generating H(2)O(2) with NAD(+) and malate as initial substrates were demonstrated by the production of dityrosine after addition of tyrosine to a reaction mixture containing NAD(+) and malate in the presence of both malate dehydrogenase fractions and purified chorion peroxidase. Data suggest that chorion peroxidase-mediated NADH/O(2) oxidoreduction may contribute to the formation of the H(2)O(2) required for chorion protein cross-linking mediated by the same peroxidase, and that the chorion associated malate dehydrogenase may be responsible for the supply of NADH for the H(2)O(2) production.

背景与目标： 埃及伊蚊中存在特定的绒毛膜过氧化物酶，该酶负责在绒毛膜硬化过程中通过二酪氨酸形成催化绒毛膜蛋白交联。过氧化物酶介导的二氢酪氨酸交联需要H（2）O（2），本研究讨论了绒毛膜过氧化物酶在H（2）O（2）形成中的可能参与，通过在绒毛膜硬化过程中介导NADH / O（2）氧化还原在埃及埃及鸡蛋中。我们的数据表明，蚊绒毛膜过氧化物酶能够催化pH依赖性的NADH氧化，在存在Mn（2）的情况下，氧化作用会增强。分子氧是过氧化物酶催化的NADH氧化过程中的电子受体，O（2）的还原导致H（2）O（2）的产生，这是通过在NADH /过氧化物酶的反应混合物中添加二氢酪氨酸形成的二氢酪氨酸所证实的。酪氨酸。埃及曲霉的卵绒毛膜中也存在能够催化苹果酸/ NAD（）氧化还原的氧化还原酶。苹果酸/ NAD（）氧化还原酶和绒毛膜过氧化物酶在以NAD（）和苹果酸为起始底物生成H（2）O（2）时的协同作用通过向含有NAD的反应混合物中添加酪氨酸后生成二酪氨酸来证明（）和苹果酸，同时存在苹果酸脱氢酶馏分和纯化的绒毛膜过氧化物酶。数据表明绒毛膜过氧化物酶介导的NADH / O（2）氧化还原可能有助于由相同的过氧化物酶介导的绒毛膜蛋白交联所需的H（2）O（2）的形成，并且绒毛膜相关的苹果酸脱氢酶可能负责为H（2）O（2）生产提供NADH。

BACKGROUND & AIMS: :Catch crop candidates (corn, guinea grass) for recovering nutrients from farm soil and aquatic plants (water caltrop, water hyacinth) were utilized to produce L-lactic acid. The efficiencies ofpre-treatment methods for enzymatic saccharification and L-lactate production of two fermentation processes, thermophilic simultaneous saccharification and fermentation (SSF), as well as separate saccharification and fermentation, were compared. Conditions were set at 55 degrees C and pH 5.5 for non-sterile fermentation. Alkaline/peroxide pre-treatment proved the most effective for saccharification in pre-treated corn, guinea grass, water caltrop and water hyacinth with glucose yields of 0.23, 0.20, 0.11 and 0.14 g/g-dry native biomass (24-hour incubation period), respectively. Examination of the two types of thermophilic L-lactate fermentation employed following alkaline/peroxide pre-treatment and saccharification demonstrated that the L-lactate yield obtained using SSF (0.15 g/g in the case of corn) was lower than that obtained using separate saccharification and fermentation (0.28 g/g in the case of corn). The lower yield obtained from SSF is likely to have resulted from the saccharification conditions used in the present study, as the possibility of cellulase deactivation during SSF by thermophilic L-lactate producing bacteria existed. A cellulase that retains high activity levels under non-sterile conditions and a L-lactate producer without cellulose hydrolysis activity would be required in order for SSF to serve as an effective method of L-lactate production.

背景与目标： ：利用候选农作物（玉米，几内亚草）从农场土壤和水生植物（菱角，水葫芦）中回收营养，以生产L-乳酸。比较了酶促糖化和L-乳酸生产两个发酵过程（高温同步糖化和发酵（SSF），以及单独的糖化和发酵）的预处理方法的效率。非无菌发酵的条件设定在55摄氏度和pH 5.5。碱性/过氧化物预处理被证明对预处理的玉米，豚鼠草，菱角和水葫芦最有效的糖化作用，其葡萄糖产量分别为干自然生物量0.23、0.20、0.11和0.14 g / g（24小时培养期） ）， 分别。对碱/过氧化物预处理和糖化后使用的两种嗜热L-乳酸发酵进行的检查表明，使用SSF获得的L-乳酸产量（对于玉米为0.15 g / g）低于使用单独糖化获得的L-乳酸产量和发酵（对于玉米为0.28 g / g）。由于存在嗜热L-乳酸的细菌在SSF中纤维素酶失活的可能性，本研究中使用的糖化条件可能导致SSF的收率降低。为了使SSF成为生产L-乳酸的有效方法，将需要在非无菌条件下保持高活性水平的纤维素酶和没有纤维素水解活性的L-乳酸生产者。

BACKGROUND & AIMS: During a screen for respiration competent yeast mutants that were unable to grow with acetate as a carbon source, two idh2 cit1 double mutants were identified. These strains were defective in the catalytic subunit of the NAD(+)-dependent isocitrate dehydrogenase and citrate synthase of the tricarboxylic acid (TCA) cycle. The strains harboring the idh2 alleles from these strains had two unusual phenotypes. First, their growth on many nonfermentable carbon sources was much poorer than strains containing other idh2 mutations. Second, the poor growth phenotype could be suppressed by the presence of mutations in CIT1 and other genes encoding oxidative functions. Spontaneous suppressor mutants that restore fast growth on glycerol medium to strains harboring two idh2 alleles were isolated, and a large percentage of the suppressor mutations have been identified within the CIT1 gene and at several other loci. Elevated levels of several TCA cycle proteins were observed in these idh2 mutants that were not observed in the presence of suppressing cit1 mutations. Citrate and isocitrate concentrations were also elevated in the idh2 mutants, but probably not to toxic levels. Five idh2 alleles were sequenced to understand the defects of the two classes of mutations. Sequence analysis indicated that the poor growth phenotype was caused by the loss of Idh2p protein. Similarly, eight cit1 alleles were sequenced to understand their characteristics as glycerol suppressors of idh2. These and other studies indicate that any mutation within CIT1 was capable of suppressing the idh2 mutations. Several models to explain these interactions are discussed.

背景与目标： 在对呼吸的筛选中，不能用乙酸盐作为碳源生长的能干酵母突变体，鉴定出两个idh2 cit1双突变体。这些菌株在三羧酸（TCA）循环的NAD（）依赖性异柠檬酸脱氢酶和柠檬酸合酶的催化亚基中存在缺陷。包含来自这些菌株的idh2等位基因的菌株具有两种不同的表型。首先，它们在许多不可发酵碳源上的生长要比含有其他idh2突变的菌株差得多。第二，生长不良的表型可以被CIT1和其他编码氧化功能的基因突变的存在所抑制。分离出自发性抑制突变体，该突变体可在甘油培养基上恢复到含有两个idh2等位基因的菌株的快速生长，并且已在CIT1基因和其他几个基因座中鉴定出很大比例的抑制突变。在这些idh2突变体中观察到几种TCA循环蛋白的水平升高，而在抑制cit1突变的情况下未观察到。在idh2突变体中柠檬酸和异柠檬酸浓度也升高，但可能没有达到毒性水平。对五个idh2等位基因进行了测序，以了解这两类突变的缺陷。序列分析表明，不良的生长表型是由Idh2p蛋白的丢失引起的。同样，对八个cit1等位基因进行了测序，以了解其作为idh2甘油抑制剂的特征。这些研究和其他研究表明，CIT1中的任何突变都能够抑制idh2突变。讨论了解释这些相互作用的几种模型。

BACKGROUND & AIMS: :This study compared the oxygen uptake (VO2) and running velocity at which the lactate threshold (LT), the ventilatory threshold (VT), and the maximal lactate steady state (MSSLA), and the maximal VO2 steady state (MSSVO2) occurred in 11 trained male runners (mean age = 22.4 years, range 18-28 years). Each underwent an incremental treadmill test to exhaustion. The LT was defined by a systematic, continuous increase in arterialised venous blood lactate; the VT was determined by an abrupt rise in VE.VO2(-1) without an increase in VE.VCO2(-1). Each subject also completed a series of steady state treadmill runs of 20 minutes duration. The MSSLA was determined as the highest velocity and VO2 at which lactate concentration increased by less than 0.2 mmol.l-1 from minute 10 to minute 20. The MSSVO2 was determined as the highest velocity or VO2 at which a steady state in VO2 was not delayed for more than 3 minutes (with a steady state defined as VO2 within 0.2 l.min-1 of the average VO2 over the last 10 minutes of each test). Each subject also completed a 5 km time trial run to assess performance. No significant differences were found among the four variables expressed either as VO2 or velocity. Significant correlations were found between MSSLA and MSSVO2 (r = 0.74) expressed as VO2, and between MSSLA and MSSVO2 (r = 0.90), MSSVO2 and VT (r = 0.70) and MSSLA and VT (r = 0.67) expressed as velocity. A stepwise regression analysis found MSSLA (expressed as velocity) to be the best predictor of 5 km performance (r = 0.87). It was concluded that (a) MSSLA and MSSVO2 are closely related, and (b) MSSLA is a good predictor of performance and may be an important, objective measure of cardiorespiratory endurance capacity.

背景与目标： ：本研究比较了在以下情况下发生的乳酸阈值（LT），通气阈值（VT），最大乳酸稳态（MSSLA）和最大VO2稳态（MSSVO2）的摄氧量（VO2）和运行速度。 11位训练有素的男性跑步者（平均年龄= 22.4岁，范围18-28岁）。每个人都进行了递增的跑步机测试，以消耗体力。 LT的定义是动脉血静脉血乳酸的系统性，持续增加。 VT是由VE.VO2（-1）的突然升高而不是VE.VCO2（-1）的升高确定的。每个受试者还完成了一系列持续20分钟的稳态跑步机。 MSSLA被确定为从10分钟到20分钟乳酸浓度增加小于0.2 mmol.l-1的最高速度和VO2。MSSVO2被确定为VO2中未达到稳态的最高速度或VO2。延迟超过3分钟（在每次测试的最后10分钟内，稳定状态定义为VO2在平均VO2的0.2 l.min-1之内）。每个受试者还完成了5公里的时间试跑以评估表现。在以VO2或速度表示的四个变量之间没有发现显着差异。发现MSSLA和MSSVO2之间（r = 0.74）表示为VO2，MSSLA和MSSVO2（r = 0.90），MSSVO2和VT（r = 0.70）和MSSLA和VT（r = 0.67）表示为显着相关。逐步回归分析发现，MSSLA（表示为速度）是5 km表现的最佳预测指标（r = 0.87）。结论是：（a）MSSLA和MSSVO2密切相关，并且（b）MSSLA是性能的良好预测指标，并且可能是心肺耐力的重要客观指标。

BACKGROUND & AIMS: :Mammalian Peptidoglycan Recognition Proteins (PGRPs) kill bacteria through induction of synergistic oxidative, thiol, and metal stress. PGRPs induce oxidative stress in bacteria through a block in the respiratory chain, which results in decreased respiration and incomplete reduction of oxygen (O2) to hydrogen peroxide (H2O2). In this study we identify the site of PGRP-induced generation of H2O2 in Escherichia coli. Tn-seq screening of E. coli Tn10 insertion library revealed that mutants in formate dehydrogenase (FDH) genes had the highest survival following PGRP treatment. Mutants lacking functional FDH-O had abolished PGRP-induced H2O2 production and the highest resistance to PGRP-induced killing, and formate enhanced PGRP-induced killing and H2O2 production in an FDH-dependent manner. Mutants in ubiquinone synthesis (but not menaquinone and demethylmenaquinone) and cytochrome bd-I (but not cytochromes bo3 and bd-II) also had completely abolished PGRP-induced H2O2 production and high resistance to PGRP-induced killing. Because electrons in the respiratory chain flow from dehydrogenases' substrates through quinones and then cytochromes to O2, these results imply that the site of PGRP-induced incomplete reduction of O2 to H2O2 is downstream from dehydrogenases and ubiquinone at the level of cytochrome bd-I, which results in oxidative stress. These results reveal several essential steps in PGRP-induced bacterial killing.

背景与目标： ：哺乳动物肽聚糖识别蛋白（PGRP）通过诱导协同氧化，硫醇和金属胁迫杀死细菌。 PGRP通过呼吸链中的阻滞诱导细菌中的氧化应激，导致呼吸减少，氧气（O2）还原为过氧化氢（H2O2）的过程不完全。在这项研究中，我们确定了PGRP诱导大肠杆菌中H2O2生成的位点。大肠杆菌Tn10插入文库的Tn-seq筛选显示，在进行PGRP处理后，甲酸脱氢酶（FDH）基因中的突变体具有最高的存活率。缺乏功能性FDH-0的突变体废除了PGRP诱导的H2O2产生和对PGRP诱导的杀灭的最高抗性，甲酸盐以FDH依赖性方式增强了PGRP诱导的杀灭和H2O2的产生。泛醌合成中的突变体（但不是甲萘醌和去甲基甲萘醌）和细胞色素bd-I（但不是细胞色素bo3和bd-II）的突变体也完全消除了PGRP诱导的H2O2产生，并且对PGRP诱导的杀灭具有很高的抵抗力。由于呼吸链中的电子从脱氢酶的底物流经醌，然后从细胞色素流向O2，因此这些结果表明，PGRP诱导的O2不完全还原为H2O2的位点在脱氢酶和泛醌的下游位于细胞色素bd-I的水平，导致氧化应激。这些结果揭示了PGRP诱导的细菌杀伤中的几个基本步骤。

BACKGROUND & AIMS: BACKGROUND:Plasmodium lactate dehydrogenase (pLDH) is a major target in diagnosing the erythrocytic stage of malaria parasites because it is highly expressed during blood-stage parasites and is distinguished from human LDH. Rapid diagnostic tests (RDTs) for malaria use pLDH as a target antigen; however, genetic variations in pLDH within the natural population threaten the efficacy of pLDH-based RDTs. METHODS:Genetic polymorphisms of Plasmodium vivax LDH (PvLDH) and Plasmodium falciparum LDH (PfLDH) in Myanmar isolates were analysed by nucleotide sequencing analysis. Genetic polymorphisms and the natural selection of PvLDH and PfLDH were analysed using DNASTAR, MEGA6, and DnaSP ver. 5.10.00 programs. The genetic diversity and natural selection of global PvLDH and PfLDH were also analysed. The haplotype network of global PvLDH and PfLDH was constructed using NETWORK ver. 5.0.0.3. Three-dimensional structures of PvLDH and PfLDH were built with YASARA Structure ver. 18.4.24 and the impact of mutations on structural change and stability was evaluated with SDM ver. 2, CUPSAT and MAESTROweb. RESULTS:Forty-nine PvLDH and 52 PfLDH sequences were obtained from Myanmar P. vivax and P. falciparum isolates. Non-synonymous nucleotide substitutions resulting in amino acid changes were identified in both Myanmar PvLDH and PfLDH. Amino acid changes were also identified in the global PvLDH and PfLDH populations, but they did not produce structural alterations in either protein. Low genetic diversity was observed in global PvLDH and PfLDH, which may be maintained by a strong purifying selection. CONCLUSION:This study extends knowledge for genetic diversity and natural selection of global PvLDH and PfLDH. Although amino acid changes were observed in global PvLDH and PfLDH, they did not alter the conformational structures of the proteins. These suggest that PvLDH and PfLDH are genetically well-conserved in global populations, which indicates that they are suitable antigens for diagnostic purpose and attractive targets for drug development.

背景与目标： 背景：乳酸疟原虫脱氢酶（pLDH）是诊断疟疾寄生虫的红细胞阶段的主要目标，因为它在血液阶段的寄生虫中高度表达，并且与人LDH有所区别。疟疾快速诊断检测（RDT）使用pLDH作为靶抗原。然而，自然种群中pLDH的遗传变异威胁了基于pLDH的RDT的功效。
方法：采用核苷酸测序技术分析缅甸分离株间日疟原虫LDH（PvLDH）和恶性疟原虫LDH（PfLDH）的基因多态性。使用DNASTAR，MEGA6和DnaSP版本分析了PvLDH和PfLDH的遗传多态性和自然选择。 5.10.00程序。还分析了全球PvLDH和PfLDH的遗传多样性和自然选择。使用NETWORK ver构建了全局PvLDH和PfLDH的单倍型网络。 5.0.0.3。使用YASARA Structure ver。构建了PvLDH和PfLDH的三维结构。 18.4.24，并使用SDM ver。评估了突变对结构变化和稳定性的影响。 2，CUPSAT和MAESTROweb。
结果：从缅甸间日疟和恶性疟原虫分离物中获得了49个PvLDH和52个PfLDH序列。在缅甸PvLDH和PfLDH中均鉴定出导致氨基酸变化的非同义核苷酸取代。在全球PvLDH和PfLDH人群中也发现了氨基酸变化，但它们在两种蛋白质中均未产生结构改变。在全球PvLDH和PfLDH中观察到低的遗传多样性，这可以通过强力的纯化选择来维持。
结论：本研究扩展了全球PvLDH和PfLDH的遗传多样性和自然选择知识。尽管在整体PvLDH和PfLDH中观察到了氨基酸变化，但它们并没有改变蛋白质的构象结构。这些表明PvLDH和PfLDH在全球人群中在遗传上是保守的，这表明它们是适合用于诊断目的的抗原和有吸引力的药物开发靶标。

BACKGROUND & AIMS: :A differentiation, based on morphological characters, between Stylonychia mytilus and Stylonychia lemnae is very difficult, especially for non-specialists. These two sibling species were considered as one species, S. mytilus, until detailed cytological and genetic studies could show the existence of two genetically isolated varieties. Further morphological and biochemical analyses verified the separation and finally in 1983 a new species S. lemnae was described. The examination of several isoenzymes revealed unambiguous differences in the banding pattern of isocitrate dehydrogenase (IDH) between these two species. Therefore, the IDH gene of 30 isolates of S. lemnae and S. mytilus coming from various regions all over the world were amplified and sequenced. The sequence analyses revealed intraspecific as well as interspecific substitutions, which were used for the development of species-specific PCR primers for both species. Application of these species-specific primer pairs now allows a very easy and clear identification of both sibling species.

背景与目标： ：在形态特征上，Mytilus和Stylonychia lemnae之间的区分是非常困难的，特别是对于非专业人士而言。直到详细的细胞学和遗传学研究表明存在两个遗传分离的变种之前，这两个兄弟姐妹种才被认为是一种S. mytilus。进一步的形态学和生化分析证实了分离，最后在1983年描述了一个新种S. lemnae。对几种同工酶的检查表明，这两个物种之间的异柠檬酸脱氢酶（IDH）的带谱模式无明显差异。因此，扩增并测序了来自世界各地的30株柠檬肉链球菌和枯草链球菌的IDH基因。序列分析揭示了种内和种间取代，这些被用于开发两个物种的物种特异性PCR引物。现在，这些物种特异性引物对的应用可以非常轻松，清晰地鉴定两个同胞物种。