scholarly journals Inhibition of glucose assimilation in Auxenochlorella protothecoides by light

2020 ◽  
Author(s):  
YIBO XIAO ◽  
Jianying Guo ◽  
Huachang Zhu ◽  
Anwar Muhammad ◽  
Haiteng Deng ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Organic Carbon ◽  
Glucose Uptake ◽  
Biomass Yield ◽  
Redox Homeostasis ◽  
Calvin Cycle ◽  
Biomass Accumulation ◽  
Auxenochlorella Protothecoides ◽  
Related Proteins ◽  
Glucose Assimilation

Abstract Background: The yield of microalgae biomass is the key to affect the accumulation of fatty acids. A few microalgae can assimilate organic carbon to improve biomass yield. In mixotrophic cultivation, microalgae can use organic carbon source and light energy simultaneously. The preference of the main energy source by microalgae determines the biomass yield. Auxenochlorella protothecoides is an oleaginous mixotrophic microalga that can efficiently assimilate glucose and accumulate a large amount of biomass and fatty acids. The current study focused on the effect of light on the growth and glucose assimilation of A. protothecoides . Results: In this study, we found that the uptake and metabolism of glucose in A. protothecoides could be inhibited by light, resulting in a reduction of biomass growth and lipid accumulation. We employed comparative proteomics to study the influence of light on the regulation of glucose assimilation in A. protothecoides . Proteomics revealed that proteins involving in gene translation and photosynthesis system were up-regulated in the light, such as ribulose-phosphate 3-epimerase and phosphoribulokinase. Calvin cycle related proteins were also up-regulated, suggesting that light may inhibit glucose metabolism by enhancing the production of glyceraldehyde-3-phosphate (G3P) in the Calvin cycle. In addition, the redox homeostasis-related proteins such as thioredoxin reductase were up-regulated in the light, indicating that light may regulate glucose uptake by changing the redox balance. Moreover, the increase of NADH levels and redox potential of the medium under illumination might inhibit the activity of the glucose transport system and subsequently reduce glucose uptake. Conclusions: A theoretical model of how glucose assimilation in A. protothecoides is negatively influenced by light was proposed, which will facilitate further studies on the complex mechanisms underlying the transition from autotrophy to heterotrophy for improving biomass accumulation.

scholarly journals Inhibition of glucose assimilation in Auxenochlorella protothecoides by light

2020 ◽  
Vol 13 (1) ◽  
Author(s):  
Yibo Xiao ◽  
Jianying Guo ◽  
Huachang Zhu ◽  
Anwar Muhammad ◽  
Haiteng Deng ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Organic Carbon ◽  
Glucose Uptake ◽  
Biomass Yield ◽  
Redox Homeostasis ◽  
Calvin Cycle ◽  
Biomass Accumulation ◽  
Auxenochlorella Protothecoides ◽  
Related Proteins ◽  
Glucose Assimilation

Abstract Background The yield of microalgae biomass is the key to affect the accumulation of fatty acids. A few microalgae can assimilate organic carbon to improve biomass yield. In mixotrophic cultivation, microalgae can use organic carbon source and light energy simultaneously. The preference of the main energy source by microalgae determines the biomass yield. Auxenochlorella protothecoides is an oleaginous mixotrophic microalga that can efficiently assimilate glucose and accumulate a large amount of biomass and fatty acids. The current study focused on the effect of light on the growth and glucose assimilation of A. protothecoides. Results In this study, we found that the uptake and metabolism of glucose in A. protothecoides could be inhibited by light, resulting in a reduction of biomass growth and lipid accumulation. We employed comparative proteomics to study the influence of light on the regulation of glucose assimilation in A. protothecoides. Proteomics revealed that proteins involving in gene translation and photosynthesis system were up-regulated in the light, such as ribulose-phosphate 3-epimerase and phosphoribulokinase. Calvin cycle-related proteins were also up-regulated, suggesting that light may inhibit glucose metabolism by enhancing the production of glyceraldehyde-3-phosphate (G3P) in the Calvin cycle. In addition, the redox homeostasis-related proteins such as thioredoxin reductase were up-regulated in the light, indicating that light may regulate glucose uptake by changing the redox balance. Moreover, the increase of NADH levels and redox potential of the medium under illumination might inhibit the activity of the glucose transport system and subsequently reduce glucose uptake. Conclusions A theoretical model of how glucose assimilation in A. protothecoides is negatively influenced by light was proposed, which will facilitate further studies on the complex mechanisms underlying the transition from autotrophy to heterotrophy for improving biomass accumulation.

scholarly journals Inhibition of glucose assimilation in Auxenochlorella protothecoides by light

2020 ◽  
Author(s):  
Yibo Xiao ◽  
Jianying Guo ◽  
Huachang Zhu ◽  
Anwar Muhammad ◽  
Haiteng Deng ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Organic Carbon ◽  
Biomass Yield ◽  
Biomass Accumulation ◽  
Glucose Transport System ◽  
Glycolysis Pathway ◽  
Auxenochlorella Protothecoides ◽  
First Time ◽  
Glucose Assimilation ◽  
Effect Of Light

Abstract Background: The yield of microalgae biomass is the key to affect the accumulation of fatty acids. A few of microalgae can assimilate organic carbon to improve biomass yield. In mixotrophic cultivation, organic carbon source and light energy exist simultaneously. The preference of the main energy source by microalgae determines the biomass yield. Auxenochlorella protothecoides is an oleaginous mixotrophic microalga that can efficiently assimilate glucose and accumulate a large amount of biomass and fatty acids. The current study focused on the effect of light on the growth and glucose assimilation of Auxenochlorella protothecoides.Results: In this study, we found that the uptake and metabolism of glucose could be inhibited by light, resulting in a reduction of biomass growth and lipid accumulation. Comparative proteomics of A. protothecoides grown under illumination and in the dark revealed that glucose-3-phosphate (G3P) produced in the dark reaction of photosynthesis could reversibly inhibit the glycolysis pathway and thus glucose metabolism. Moreover, the increase of NADH levels and redox potential of the medium under illumination might inhibit the activity of the glucose transport system and subsequently reduce glucose uptake.Conclusions: The regulatory mechanism by which illumination controls glucose assimilation and biomass accumulation in A. protothecoides was elucidated for the first time, which will facilitate further studies on the complex mechanisms underlying the transition from autotrophy to heterotrophy for improving biomass accumulation.

Efficiency of transfer of essential polyunsaturated fatty acids versus organic carbon from producers to consumers in a eutrophic reservoir

Oecologia ◽  
2010 ◽  
Vol 165 (2) ◽  
pp. 521-531 ◽  
Author(s):  
Michail I. Gladyshev ◽  
Nadezhda N. Sushchik ◽  
Olesia V. Anishchenko ◽  
Olesia N. Makhutova ◽  
Vladimir I. Kolmakov ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Organic Carbon ◽  
Polyunsaturated Fatty Acids ◽  
Eutrophic Reservoir

scholarly journals Insulinomimetic Zn(II) Complexes as Evaluated by Both Glucose-Uptake Activity and Inhibition of Free Fatty Acids Release in Isolated Rat Adipocytes

2008 ◽  
Vol 56 (8) ◽  
pp. 1181-1183 ◽  
Author(s):  
Midori Nishide ◽  
Yutaka Yoshikawa ◽  
Eriko U. Yoshikawa ◽  
Kinuyo Matsumoto ◽  
Hiromu Sakurai ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Free Fatty Acids ◽  
Glucose Uptake ◽  
Rat Adipocytes ◽  
Uptake Activity ◽  
Isolated Rat

scholarly journals Atypical Antipsychotic Drug Olanzapine Deregulates Hepatic Lipid Metabolism and Aortic Inflammation and Aggravates Atherosclerosis

2018 ◽  
Vol 50 (4) ◽  
pp. 1216-1229 ◽  
Author(s):  
Chia-Hui Chen ◽  
Song-Kun Shyue ◽  
Chiao-Po Hsu ◽  
Tzong-Shyuan Lee
Keyword(s):  
Fatty Acids ◽  
Lipid Metabolism ◽  
Atypical Antipsychotic ◽  
Antipsychotic Drug ◽  
Free Cholesterol ◽  
Hepatic Lipid Metabolism ◽  
Atypical Antipsychotic Drug ◽  
In Vivo Models ◽  
Hepatic Lipid ◽  
Related Proteins

Background/Aims: Olanzapine, an atypical antipsychotic drug, has therapeutic effects for schizophrenia. However, clinical reports indicate that patients taking atypical antipsychotic drugs are at high risk of metabolic syndrome with unclear mechanisms. We investigated the effect of olanzapine on atherosclerosis and the mechanisms in apolipoprotein E-null (apoE-/-) mice. Methods: ApoE-/- mice were used as in vivo models. Western blot analysis was used to evaluate protein expression. Conventional assay kits were applied to assess the levels of cholesterol, triglycerides, free cholesterol, cholesteryl ester, fatty acids, glycerol, and cytokines. Results: Daily treatment with olanzapine (3 mg/kg body weight) for four weeks increased mean arterial blood pressure and the whitening of brown adipose tissue in mice. In addition, olanzapine impaired aortic cholesterol homeostasis and exacerbated hyperlipidemia and aortic inflammation, which accelerated atherosclerosis in mice. Moreover, lipid accumulation in liver, particularly total cholesterol, free cholesterol, fatty acids, and glycerol, was increased with olanzapine treatment in apoE-/- mice by upregulating the expression of de novo lipid synthesis-related proteins and downregulating that of cholesterol clearance- or very low-density lipoprotein secretion-related proteins. Conclusion: Olanzapine may exacerbate atherosclerosis by deregulating hepatic lipid metabolism and worsening hyperlipidemia and aortic inflammation.

scholarly journals Distinct effects of oleic acid and itstrans-isomer elaidic acid on the expression of myokines and adipokines in cell models

2011 ◽  
Vol 105 (8) ◽  
pp. 1226-1234 ◽  
Author(s):  
Nuria Granados ◽  
Jaume Amengual ◽  
Joan Ribot ◽  
Andreu Palou ◽  
M. Luisa Bonet
Keyword(s):  
Gene Expression ◽  
Fatty Acids ◽  
Oleic Acid ◽  
Insulin Sensitivity ◽  
Glucose Uptake ◽  
Elaidic Acid ◽  
C2c12 Myotubes ◽  
Cell Models ◽  
Monounsaturated Fat ◽  
Expression Levels

Trans-fatty acids (TFA) andcis-monounsaturated fat appear to exert detrimental and beneficial effects, respectively, on glucose metabolism and insulin sensitivity. Adipose tissue and skeletal muscle are a source of signalling proteins (adipokines and myokines), some of which have been related to the control of insulin sensitivity. Here, we investigated the possible differential effects of elaidic acid (EA;trans-9-18 : 1) – the major component in industrially produced TFA – and oleic acid (OA;cis-9-18 : 1) – itscis-isomer naturally present in food – on cellular glucose uptake and the expression of selected myokines and adipokines using cell models. Differentiated C2C12 myotubes and 3T3-L1 adipocytes were pretreated with the vehicle (control cells) or fatty acids for 24 h, after which basal and insulin-stimulated 2-deoxyglucose uptake and the expression of selected signalling proteins were measured. In C2C12 myotubes, pretreatment with OA, but not with EA, led to increased insulin-stimulated 2-deoxyglucose uptake and IL-6 expression levels, while pretreatment with EA, but not with OA, led to reduced IL-15 mRNA levels and increased TNF-α expression levels. In 3T3-L1 adipocytes, exposure to OA, but not to EA, resulted in reduced resistin gene expression and increased adiponectin gene expression. The results show evidence of distinct, direct effects of OA and EA on muscle glucose uptake and the expression of target myokines and adipokines, thus suggesting novel mechanisms by whichcis- andtrans-monounsaturated fat may differentially affect systemic functions.

scholarly journals Prominent bacterial heterotrophy and sources of <sup>13</sup>C-depleted fatty acids to the interior Canada Basin

2013 ◽  
Vol 10 (11) ◽  
pp. 7065-7080 ◽  
Author(s):  
S. R. Shah ◽  
D. R. Griffith ◽  
V. Galy ◽  
A. P. McNichol ◽  
T. I. Eglinton
Keyword(s):  
Fatty Acids ◽  
Particulate Matter ◽  
Organic Carbon ◽  
Suspended Particulate Matter ◽  
Surface Waters ◽  
Canada Basin ◽  
The Arctic ◽  
Deep Basin ◽  
Suspended Particulate ◽  
Chemoautotrophic Bacteria

Abstract. In recent decades, the Canada Basin of the Arctic Ocean has experienced rapidly decreasing summer sea ice coverage and freshening of surface waters. It is unclear how these changes translate to deeper waters, particularly as our baseline understanding of organic carbon cycling in the deep basin is quite limited. In this study, we describe full-depth profiles of the abundance, distribution and carbon isotopic composition of fatty acids from suspended particulate matter at a seasonally ice-free station and a semi-permanently ice-covered station. Fatty acids, along with suspended particulate organic carbon (POC), are more concentrated and 13C-enriched under ice cover than in ice-free waters. But this influence, apparent at 50 m depth, does not propagate downward below 150 m depth, likely due to the weak biological pump in the central Canada Basin. Branched fatty acids have δ13C values that are similar to suspended POC at all depths and are more 13C-enriched than even-numbered saturated fatty acids at depths above 3000 m. These are likely to be produced in situ by heterotrophic bacteria incorporating organic carbon that is isotopically similar to total suspended POC. Below surface waters, there is also the suggestion of a source of saturated even-numbered fatty acids which could represent contributions from laterally advected organic carbon and/or from chemoautotrophic bacteria. At 3000 m depth and below, a greater relative abundance of long-chain (C20–24), branched and unsaturated fatty acids is consistent with a stronger influence of re-suspended sedimentary organic carbon. At these deep depths, two individual fatty acids (C12 and iso-C17) are significantly depleted in 13C, allowing for the possibility that methane oxidizing bacteria contribute fatty acids, either directly to suspended particulate matter or to shallow sediments that are subsequently mobilized and incorporated into suspended particulate matter within the deep basin.

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