Cell Fatty Acid Research Articles

Jiangella endophytica sp. nov., an endophytic actinomycete isolated from the rhizome of Kaempferia elegans

An endophytic actinobacterium, designated strain KE2-3T, was isolated from surface-sterilised rhizome of Kaempferia elegans. The polyphasic approach was used for evaluating the taxonomic position of this strain. The taxonomic affiliation of this strain at genus level could be confirmed by its chemotaxonomic characteristic, i.e. the presence of ll-diaminopimelic acid in the cell peptidoglycan, MK-9(H4) as the major menaquinone, iso-C16 : 0, anteiso-C15 : 0, iso-C14 : 0 and iso-C15 : 0 as the predominant fatty acids in cells, and the presence of diphosphatidylglycerol, phosphatidylglycerol, phosphatidylinositol and phosphatidylinositol mannoside in its membranes. Based on 16S rRNA gene sequence analysis, strain KE2-3T was identified as a member of the genus Jiangella and showed the highest similarities to Jiangella muralis DSM 45357T (99.3 %) followed by Jiangella albaDSM 45237T (99.2 %), Jiangella alkaliphilia DSM 45079T (99.0 %), Jiangella gansuensisDSM 44835T (98.8 %) and Jiangella mangrovi3SM4-07T (98.6 %). However, the draft genome sequence of strain KE2-3T exhibited low average nucleotide identity values to the reference strains (85.5-90.2 %), which were well below the 95-96 % species circumscription threshold. The DNA G+C content of genomic DNA was 72.3 mol%. With the differences of physiological, biochemical and genotypic data, strain KE2-3T could be discriminated from its closest neighbour. Thus, strain KE2-3T should be recognised as a novel species of genus Jiangella, for which the name Jiangellaendophytica sp. nov. is proposed. The type strain is KE2-3T (=BCC 66359T=NBRC 110004T).

Mesorhizobium wenxiniae sp. nov., isolated from chickpea (Cicer arietinum L.) in China.

Three chickpea rhizobial strains (WYCCWR 10195T=S1-3-7, WYCCWR 10198=S1-4-3 and WYCCWR 10200=S1-5-1) isolated from Northwest China formed a group affiliated to Mesorhizobium based on 16S rRNA gene sequence comparison. To clarify their species status, multilocus sequence analysis and average nucleotide identity (ANI) values of whole genome sequences between the novel group and the type strains of the related species were further performed. Similarities of 95.7-96.6 % in the concatenated sequences of atpD-recA-glnII and 91.9-93.1 % of ANI values to the closest-related species Mesorhizobium muleiense, Mesorhizobium mediterraneum and Mesorhizobium temperatum demonstrated the novel group a unique genospecies. The most abundant fatty acid in cells of WYCCWR 10195T were C19 : 0 cyclo ω8c (51.4 %), followed by C18 : 1 ω7c 11-methyl (9.5 %) and C16 : 0 (9.3 %). Its genome size was 6.37 Mbp, comprising 6633 predicted genes with a DNA G+C content of 61.9 mol%. The similarities of 99.0-99.8 % for the nodC gene and 98.3-99.44 % for the nifH gene to those of the chickpea rhizobial species and nodulation with Cicer arietinum L. confirmed the strains of the new genospecies as symbiovar ciceri. The weak utilization of most of the tested sugars/organic acids and non-utilization of l(+)-rhamnose, l-cysteine and l-glycine as sole carbon source, tolerance to 1 % (w/v) NaCl, resistance to 5 µg ml-1 chloromycetin and non-hydrolysis of l-tyrosine distinguished the novel group from the related species and supported this group as a novel species, for which the name Mesorhizobium wenxiniae sp. nov. is proposed, with WYCCWR 10195T (=S1-3-7=HAMBI 3692T=LMG 30254T) as the type strain.

Substrate specificity of acyl-lipid Δ9-desaturase from Prochlorothrix hollandica cyanobacterium producing myristoleic acid

Chlorophyll b-containing cyanobacterium Prochlorothrix hollandica is characterized by a high content of esterified fatty acids (FA) with 14 and 16 carbon atoms in the membrane lipids. Depending on the conditions of cultivation, the relative amount of myristic (C14:0) and myristoleic (C14:1) acids can reach 35%, and palmitic (С16:0) and palmitoleic (С16:1) acids can reach 60% of the sum of all fatty acids in cells. Monounsaturated FAs are represented by C14:1, and C16:1 with an olefinic bond presumably located in the Δ9 position. We cloned the gene of acyl-lipid Δ9-desaturase, desC1, from Prochlorothrix hollandica and characterized its specificity to the length of the substrate using the heterologous expression in Escherichia coli cells adding C14:0 or stearic (C18:0) acids as exogenous substrates. The results show that DesC1 Δ9 desaturase generates olefinic bonds in the FAs with a length of 14 to 18 carbon atoms with an approximately equal efficiency. This indicates that the length of the FA chain in P. hollandica is determined by the activity of the FA synthase, and the chain is desaturated at the Δ9 position nonspecifically relatively to its length.

The atherosclerosis and atheromatosis as two etiologically different aphysiological processes at single pathogenesis. Atheromatosis and pathogenetic role of insulin.

It is supposed that at stages of phylogenesis seven biological functions was developed: 1) biological function of trophology; 2) homeostasis; 3) endoecology; 4) adaptation; 5) continuation of species; 6) locomotion; 7) cognitive function, including intellect. The function of trophology (feeding) is implemented by two biological reactions: exophilia - external feeding and endophilia - internal feeding. The function of endoecology prevents exceeding of upper limit of physiological interval by no substrate, catabolites and endogenous phlogogens. It is implemented by two biological functions: excretion and inflammation. The etiological factors of atherosclerosis are the following ones. The oleic mono-saturated fatty acid in chemical reactions is by far more active than palmitic fatty acid. In the ocean, all animals were carnivorous (piscivorous); species Homo Sapiens, in millions of years of life on dry land, forcedly became a herbivorousone. The main role in development of herbivorous animals belongs to insulin; the hormone regulating in the first-place metabolism of fatty acids, expresses transmutation of all endogenously synthesized from glucose palmitic saturated fatty acid in oleic monosaturated fatty acid. The late in phylogenesis insulin can't initiate transmutation of exogenous palmitic saturated fatty acid of food into oleic mono-saturated fatty acid. Under effect of insulin in vivo an active oleic type of metabolism of fatty acids is developed; and outside if effect of insulin palmitic type of metabolism of fatty acids is developed. In the ocean, synthesis of active eicosanoids occurs from ῳ-3 polyene fatty acids; there is no such fatty acids in dry land. The basis of pathogenesis of atherosclerosis is feeding of large amount of carnivorous (meat) food by phylogenetically herbivorous Homo Sapiens. This way a deficiency of palmitic saturated fatty acids in cells if developed blocking their bio-accessibility. The lipoproteins of low density are not developed in the initiated by insulin transfer of oleic triglycerides to cells in oleic apoE/B-100 lipoproteins of very low density and their absorption by cells. The transfer of triglycerides into lipoproteins of very low density is blocked under slow processes of transmutation of palmitic lipoproteins of very low density into lipoproteins of low density, retention cumulation of lipoproteins of low density in blood. Only because of partial utilization by monocytes of non-ligand palmitic lipoproteins of very low density →lipoproteins of low density that occurs in the intima of arteries of elastic type, atheromotosis is developed. The atheromotosis masses of intima are first of all interim catabolites of polyene fatty acids; the cells could not to absorb them by apoB-100-endocytosis in the content of lipoproteins of low density. The atherosclerosis, hyperlipoproteinemia, high content of lipoproteins of low density in blood and deficiency of polyene fatty acids in cells are a result of disorder of trophology function; the atheromotosis of arteries is only partial implementation of endoecology function.

The physical chemical and biological features of triglycerides. The cell absorption of functionally different palmitic+oleic lipoproteins of very low and density and linoleic+linolenic lipoproteins of low density.

The earlier insulin-independent low-density lipoproteins and more late insulin-dependent very low-density lipoproteins implement different functions at the stages of phylogenesis. The disorder of biological function of trophology, alteration of fatty acids in triglycerides, prevalence of palmitic very low-density lipoproteins over oleic very low-density lipoproteins supply mitochondria of cells with non-optimal substrate - palmitic saturated fatty acid for gaining energy, ATP synthesis. Physiologically, cells implement oleic alternative of fatty acids metabolism, oxidizing mainly ω-9 endogenous oleic mono-unsaturated fatty acid. The pathology of low density lipoproteins is primary deficiency of poly-unsaturated fatty acids in cells, atherosclerosis and atheromotosis of intima of arteries of elastic type with development of dense plaques from poly-unsaturated fatty acids in the form of polyethers of cholesterol. The pathology of very low-density lipoproteins includes: a) syndrome of resistance to insulin; b) pathology of phylogenetically earlier insulin-independent visceral fatty tissue - metabolic syndrome; c) pathology of phylogenetically later insulin-dependent subcutaneous adipocytes - obesity; d) secondary atherosclerosis, under cumulation of palmitic low-density lipoproteins in blood with development of atherothrombosis of intima of arteries, soft plaques rich with triglycerides. As for the prevention of disorders of transfer of fatty acids to very low-density lipoproteins and low-density lipoproteins is common in many ways - minimization of aphysiological effect of surplus amount of food, biological function of diet. The prevention at the level of population includes: a) maximal limitation of content of palmitic saturated fatty acid in food; b) moderate increasing of polysaturated fatty acids, ω-3 poly-saturated fatty acids predominantly; c) increasing of physical activity. The pharmaceuticals are not provided by biology in primary prevention of metabolic pandemics under aphysiological impact of environment factors.

The individual fatty acids of blood plasma: biological role of substrates, parameters of quantity and quality, diagnostic of atherosclerosis and atheromotosis.

The atherosclerosis and atheromotosis are supposed to be, according to phylogenetic theory of general pathology, two etiologically different aphysiological processes, unified by community of pathogenesis. The atherosclerosis is a derangement of biological function of trophology (feeding), biological reaction of exotrophy (external feeding) and biological function of adaptation, biological reaction of compensation in response to deficiency of ῳ-3 and ῳ-6 polyenoic fatty acids. In case of deficiency of polyenoic fatty acids in cells and during synthesis of eicosanoids of group I from unsaturated endogenous ῳ-6 С20: 3 digomo-γ-linoleic unsaturated fatty acid, atherosclerosis is developed, a complex metabolism disorder in vivo. The atheromotosis is a derangement of biological function of endoecology, biological reactions of inflammation and inherent immunity. This incomplete utilization in intima of arteries of non-ligand palmitic lipoproteins of very low → low density under effect not of polyfunctional resident macrophage but monocytes of hematogenic origin without expression of acid hydrolase of polyenoic ethers of cholesterol. In intima, in area of cumulation of endogenous phlogogens (initiator of inflammation) from the pool of intra-vascular medium, polyenoic unsaturated fatty acids are cumulated that were not absorbed by cells in structure of ligand low density palmitic lipoproteins using apoB-100- endocytosis. The pathogenic factor of atherosclerosis - derangement of biological function of trophology. biological function of exotrophy under alimentary deficiency of in vivo of ῳ-3 and ῳ-6 polyenoic fatty acids with physiological parameters of feeding. The pathogenic factor of atheromotosis - phylogenetically herbivorous (carnivorous) human misusing of animal (meat) food, palmitic unsaturated fatty acids, development by hepatocytes of a large number of palmitic triglycerides and lipoproteins of very low density of the same name. The late in phylogenesis insulin-dependent lipoproteins of very low density transfer palmitic lipoproteins of very low density to cells slowly. The cells absorb them also slowly. The cumulation of non-ligand palmitic lipoproteins of very low density → low density in blood competitively blocks physiological absorption of polyenoic unsaturated fatty acids by cells in structure of physiological palmitic lipoproteins of low density. The atherosclerosis occurs blood flow and atheromotosis in intima of arteries of elastic type.

Effects of carbon source and light intensity on the growth and total lipid production of three microalgae under different culture conditions.

We attempted to enhance the growth and total lipid production of three microalgal species, Isochrysis galbana LB987, Nannochloropsis oculata CCAP849/1, and Dunaliella salina, which are capable of accumulating high content of lipid in cells. Low nitrogen concentration under photoautotrophic conditions stimulated total lipid production, but a decreasing total lipid content and an increasing biomass were observed with increasing nitrogen concentration. Among the different carbon sources tested for heterotrophic cultivation, glucose improved the growth of all three strains. The optimal glucose concentration for growth of I. galbana LB987 and N. oculata CCAP849/1 was 0.02M, and that of D. salina was 0.05M. Enhanced growth occurred when they were cultivated under heterotrophic or mixotrophic conditions compared with photoautotrophic conditions. Meanwhile, high total lipid accumulation in cells occurred when they were cultivated under photoautotrophic or mixotrophic conditions. During mixotrophic cultivation, biomass production was not affected significantly by light intensity; however, both chlorophyll concentration and total lipid content increased dramatically with increasing light intensity up to 150µmol/m(2)/s. The amount and composition ratio of saturated and unsaturated fatty acids in cells were different from each other depending on both species and light intensity. The highest accumulation of total fatty acid (C16-C18) among the three strains was found from cells of N. oculata CCAP849/1, which indicates that this species can be used as a source for production of biodiesel.

Sunflower (Helianthus annuus) fatty acid synthase complex: β-hydroxyacyl-[acyl carrier protein] dehydratase genes.

Two sunflower hydroxyacyl-[acyl carrier protein] dehydratases evolved into two different isoenzymes showing distinctive expression levels and kinetics' efficiencies. β-Hydroxyacyl-[acyl carrier protein (ACP)]-dehydratase (HAD) is a component of the type II fatty acid synthase complex involved in 'de novo' fatty acid biosynthesis in plants. This complex, formed by four intraplastidial proteins, is responsible for the sequential condensation of two-carbon units, leading to 16- and 18-C acyl-ACP. HAD dehydrates 3-hydroxyacyl-ACP generating trans-2-enoyl-ACP. With the aim of a further understanding of fatty acid biosynthesis in sunflower (Helianthus annuus) seeds, two β-hydroxyacyl-[ACP] dehydratase genes have been cloned from developing seeds, HaHAD1 (GenBank HM044767) and HaHAD2 (GenBank GU595454). Genomic DNA gel blot analyses suggest that both are single copy genes. Differences in their expression patterns across plant tissues were detected. Higher levels of HaHAD2 in the initial stages of seed development inferred its key role in seed storage fatty acid synthesis. That HaHAD1 expression levels remained constant across most tissues suggest a housekeeping function. Heterologous expression of these genes in E. coli confirmed both proteins were functional and able to interact with the bacterial complex 'in vivo'. The large increase of saturated fatty acids in cells expressing HaHAD1 and HaHAD2 supports the idea that these HAD genes are closely related to the E. coli FabZ gene. The proposed three-dimensional models of HaHAD1 and HaHAD2 revealed differences at the entrance to the catalytic tunnel attributable to Phe166/Val1159, respectively. HaHAD1F166V was generated to study the function of this residue. The 'in vitro' enzymatic characterization of the three HAD proteins demonstrated all were active, with the mutant having intermediate K m and V max values to the wild-type proteins.

Trace concentrations of iron nanoparticles cause overproduction of biomass and lipids during cultivation of cyanobacteria and microalgae

Cultivation in Zehnder medium containing 5.1 mg L−1 zero-valent iron nanoparticles (nZVI) boosted the growth of the green algae Desmodesmus subspicatus, Dunaliella salina, Parachlorella kessleri and Raphidocelis subcapitata and the eustigmatophycean algae Nannochloropsis limnetica and Trachydiscus minutus. In the cyanobacterium Arthrospira maxima, growth stimulation occurred at 1.7–5.1 mg L−1 nZVI. In all studied microorganisms, 5.1 mg L−1 nZVI strongly enhanced lipid accumulation, decreased the content of saturated and monounsaturated fatty acids with the exception of palmitoleic acid and increased the content of polyunsaturated fatty acids in cells. The nZVI particles may provide a suitable source of iron causing increased cell growth and induce metabolic changes resulting in higher lipid production and changes in fatty acid (FA) composition. Altered lipid synthesis may reflect the oxidative action of nZVI. Further research may contribute to optimizing the economical production of oils from oleaginous microorganisms and help clarify the mechanism of nZVI action.

The Relative Proportions of Different Lipid Classes and their Fatty Acid Compositions Change with Culture Age in the Cariogenic Dental PathogenStreptococcus mutansUA159

The oral cariogenic bacterial pathogen Streptococcus mutans strain UA159 has become an important research organism strain since its genome was sequenced. However, there is a paucity of information on its lipidome using direct analytical biochemical approaches. We here report on comprehensive analyses of the major lipid classes and their fatty acids in cells grown in batch standing cultures. Using 2-D high-performance thin-layer chromatography lipid class composition changes were detected with culture age. More lipid components were detected in the stationary-phase compared to log-phase cells. The major lipids identified included 1,3-bis(sn-3'-phosphatidyl)-sn-glycerol (phosphatidylglycerol), 1,3-diphosphatidylglycerol (cardiolipin), aminoacyl-phosphatidylglycerol, monoglucosyldiacylglycerol, diglucosyldiacylglycerol, diglucosylmonoacylglycerol and, glycerophosphoryldiglucosyldiacylglycerol. Culture age also affected the fatty acid composition of the total polar lipid fraction. Thus, the major lipid classes detected in log-phase and stationary-phase cells were isolated and their fatty acids were analyzed by gas-liquid chromatography to determine the basis for the fatty acid compositional changes in the total polar lipid fraction. The analyses showed that the relative proportions of these acids changed with culture age within individual lipid classes. Hence fatty acid changes in the total polar lipid fraction reflected changes in both lipid class composition and fatty acid compositions within individual lipid classes.

11th Euro Fed Lipid Congress, New Strategies for a High Quality Future (27–30 October 2013, Antalya, Turkey)

11th Euro Fed Lipid Congress, New Strategies for a High Quality Future (27–30 October 2013, Antalya, Turkey)

Effect of FASN gene on milk yield and milk composition in the Chinese Holstein dairy population

Fatty acid synthase (FASN) is a multifunctional protein that catalyzes de novo synthesis of fatty acids in cells. It plays a key role in the lipid biosynthesis as well as in the general metabolism of all living animals. We herein investigated polymorphisms of FASN. As a result, six single nucleotide polymorphisms (SNPs) were found and then genotyped in 752 Chinese Holstein cows. It was found that g.17924A>G was non-synonymous, g.13965 C>T, g.16907 T>C and g.18663T>C were synonymous mutations and two other two SNPs, g.8948 C>T (ss491228481) and g.14439T>C (rs133498277), were in intronic sequences of the gene. All such identified SNPs were found to be associated with milk yield and composition traits (P=0.0441 to <0.0001). Significant additive and allele substitution effects were observed for three yield traits at all six loci as well (P<0.05 to <0.01). Complete linkage disequilibrium among the five SNPs, with the exception of g.8948 C>T, was observed.

The effect of valinomycin in fibroblasts from patients with fatty acid oxidation disorders

Disorders of the carnitine cycle and of the beta oxidation spiral impair the ability to obtain energy from fats at time of fasting and stress. This can result in hypoketotic hypoglycemia, cardiomyopathy, cardiac arrhythmia and other chronic medical problems. The in vitro study of fibroblasts from patients with these conditions is impaired by their limited oxidative capacity. Here we evaluate the capacity of valinomycin, a potassium ionophore that increases mitochondrial respiration, to increase the oxidation of fatty acids in cells from patients with inherited fatty acid oxidation defects. The addition of valinomycin to fibroblasts decreased the accumulation of the lipophilic cation tetraphenylphosphonium (TPP+) at low concentrations due to the dissipation of the mitochondrial membrane potential. At higher doses, valinomycin increased TPP+ accumulation due to the increased potassium permeability of the plasma membrane and subsequent cellular hyperpolarization. The incubation of normal fibroblasts with valinomycin increased [14C]-palmitate oxidation (measured as [14C]O2 release) in a dose-dependent manner. By contrast, valinomycin failed to increase palmitate oxidation in fibroblasts from patients with very long chain acyl CoA dehydrogenase (VLCAD) deficiency. This was not observed in fibroblasts from patients heterozygous for this condition. These results indicate that valinomycin can increase fatty acid oxidation in normal fibroblasts and could be useful to differentiate heterozygotes from patients affected with VLCAD deficiency.

Structural Basis for the Mutation-Induced Dysfunction of Human CYP2J2: A Computational Study

Arachidonic acid is an essential fatty acid in cells, acting as a key inflammatory intermediate in inflammatory reactions. In cardiac tissues, CYP2J2 can adopt arachidonic acid as a major substrate to produce epoxyeicosatrienoic acids (EETs), which can protect endothelial cells from ischemic or hypoxic injuries and have been implicated in the pathogenesis of coronary artery disease and hypertension. However, some CYP2J2 polymorphisms, i.e., T143A and N404Y, significantly reduce the metabolism of arachidonic acid. Lacking experimental structural data for CYP2J2, the detailed mechanism for the mutation-induced dysfunction in the metabolism of arachidonic acid is still unknown. In the current study, three-dimensional structural models of the wild-type CYP2J2 and two mutants (T143A and N404Y) were constructed by a coordinate reconstruction approach and ab initio modeling using CYP2R1 as a template. The structural analysis of the computational models showed that the wild-type CYP2J2 exhibited a typical CYP fold with 12 alpha-helices and three beta-sheets on one side and with the heme group buried deeply inside the core. Due to the small and hydrophobic side-chain, T143A mutation could destabilize the C helix, further placing the water access channel in a closed state to prevent the escape of the produced water molecules during the catalytic processes. N404Y mutation could reposition the side-chain of Leu(378), making it no longer form a hydrogen bond with the carboxyl group of arachidonic acid. However, this hydrogen bond was essential for substrate recognition and positioning in a correct orientation.

Self-Assembled Nanostructures of Fully Hydrated Monoelaidin–Elaidic Acid and Monoelaidin–Oleic Acid Systems

In recent years, there has been a surge of interest in exploring the effect of trans-fatty acids (TFAs) on biological membrane properties. The research studies are motivated by an increasing body of evidence suggesting that the consumption of TFAs increases the risk of developing negative health effects such as coronary heart disease and cancer. The ultimate goal of studying the lipid-fatty acid interactions at the molecular level is to predict the biological role of fatty acids in cells. In this regard, it is interesting to elucidate the effect of loading TFAs and their counterpart cis-fatty acids (CFAs) on the physical properties of lipid model membranes. Here, the present study focuses on discussing the following: (1) the effect of mixing monoelaidin (ME, TFA-containing lipid) with its counterpart monoolein (MO, CFA-containing lipid) on modulating the fully hydrated self-assembled structure, and (2) the influence of solubilizing oleic acid (OA) and its trans counterpart elaidic acid (EA) on the fully hydrated ME system. The ME model membrane was selected due to its sensitivity to variations in lipid composition and temperature. Synchrotron small-angle X-ray scattering (SAXS) was applied for studying the temperature-dependent structural behavior of the fully hydrated ME/MO-based system prepared with an equal ME/MO weight ratio and also for characterizing the fully hydrated OA- and EA-loaded ME systems. Wide-angle X-ray (WAXS) experiments were also performed for characterizing the formed crystalline lamellar phases at ambient temperatures. The results demonstrate the significant influence of the partial replacement of ME by MO on the phase behavior. The addition of MO induces the lamellar-nonlamellar phase transitions at ambient temperatures and promotes the formation of the inverted type hexagonal (H(2)) phase above 72 °C. The fully hydrated ME/EA and ME/OA systems with their rich polymorphism exhibit an interesting temperature-dependent complex behavior. The experimental findings show that the temperature-induced phase transitions are dictated by the solubilized fatty acid concentration and its configuration. Both EA and OA have a significant impact on the fully hydrated ME system. Similar to previous published studies, OA induces a significantly stronger mean negative membrane curvature as compared to EA. The two phase diagrams are discussed in terms of water-lipid and lipid-fatty acid interactions, membrane bending, and lipid packing concepts. A newly observed interesting epitaxial relationship for the lamellar-hexagonal phase transition in the EA-loaded ME system is illustrated and discussed in detail.

Abstract 25: Inhibition of VLDL Assembly by Apolipoprotein B Antisense Oligonucleotides Stimulates Autophagy

In order to investigate the effects of reduced VLDL secretion on hepatic lipid metabolism, we examined the effects of knockdown of either apolipoproteinB (apoB) or microsomal triglyceride transfer protein (MTP) using antisense oligonucleotides (ASO) for 6 weeks in apobec-1 knockout mice that only synthesize apoB100. Despite a similar decrease VLDL secretion in mice treated with apoB ASO as compared with MTP ASO, there was an increase in liver triglyceride (TG) content only in the MTP ASO-treated mice. There were no differences in either fatty acid (FA) uptake or secretion, or lipid synthesis from de novo lipogenesis, between the two groups to explain the difference in liver TG mass. In primary hepatocytes isolated from mice treated with apoB ASO, FA oxidation measured after a 16 hr steady state label with 14 C oleic acid showed a 3 fold increase in FA oxidation versus cells from control ASO-treated mice. A labeled time course study showed that the increase in FA oxidation was delayed, indicating compartmentalization of lipid in the apoB ASO-treated hepatocytes. Electron microsopy (EM) showed swollen endoplasmic reticulum (ER) and increased autophagosomes in the apoB ASO hepatocytes. The latter was confirmed by an increase in immunofluoresent staining for the autophagy marker LC3b. The LC3b protein was perinuclear suggesting that it was present on mature autophagolysosomes. Treatment with lysosomal inhibitors showed that the accumulation of LC3b was not due to a defect in autophagic flux in these hepatocytes. Autophagosomes in the EMs contained large double membrane structures suggestive of ER. In primary hepatocytes from apoB ASO-treated mice, labeling with ER Tracker showed abnormal aggregates of ER. In addition, immunofluorescent staining studies showed that these abnormal ER aggregates, as represented by calnexin staining, co-localized with the LC3b protein. We propose that autophagy of lipid-filled ER, with subsequent lipolysis of TG in the autophagolysosome and later oxidation of released FA, prevent hepatic steatosis in mice treated with apoB ASO.

Antarctic marine bacterium Pseudoalteromonas sp. KNOUC808 as a source of cold-adapted lactose hydrolyzing enzyme

Psychrophilic bacteria, which grow on lactose as a carbon source, were isolated from Antarctic polar sea water. Among the psychrophilic bacteria isolated, strain KNOUC808 was able to grow on lactose at below 5°C, and showed 0.867 unit of o-nitrophenyl β-D-galactopyranoside(ONPG) hydrolyzing activity at 4°C. The isolate was gram-negative, rod, aerobic, catalase positive and oxidase positive. Optimum growth was done at 20°C, pH 6.8-7.2. The composition of major fatty acids in cell of KNOUC801 was C12:0 (5.48%), C12:0 3OH (9.21%), C16:0 (41.83%), C17:0 ω8 (7.24%) and C18:1 ω7 (7.04%). All these results together suggest that it is affiliated with Pseudoalteromonas genus. The 16S rDNA sequence corroborate the phenotypic tests and the novel strain was designated as Pseudoalteromonas sp. KNOUC808. The optimum temperature and pH for lactose hydrolyzing enzyme was 20°C and 7.8, respectively. The enzyme was stable at 4°C for 7 days, but its activity decreased to about 50% of initial activity at 37°C in 7 days.

Antarctic marine bacterium Pseudoalteromonas sp. KNOUC808 as a source of cold-adapted lactose hydrolyzing enzyme

Psychrophilic bacteria, which grow on lactose as a carbon source, were isolated from Antarctic polar sea water. Among the psychrophilic bacteria isolated, strain KNOUC808 was able to grow on lactose at below 5°C, and showed 0.867 unit of o-nitrophenyl β-D-galactopyranoside(ONPG) hydrolyzing activity at 4°C. The isolate was gram-negative, rod, aerobic, catalase positive and oxidase positive. Optimum growth was done at 20°C, pH 6.8–7.2. The composition of major fatty acids in cell of KNOUC801 was C12:0 (5.48%), C12:0 3OH (9.21%), C16:0 (41.83%), C17:0 ω8 (7.24%) and C18:1 ω7 (7.04%). All these results together suggest that it is affiliated with Pseudoalteromonas genus. The 16S rDNA sequence corroborate the phenotypic tests and the novel strain was designated as Pseudoalteromonas sp. KNOUC808. The optimum temperature and pH for lactose hydrolyzing enzyme was 20°C and 7.8, respectively. The enzyme was stable at 4°C for 7 days, but its activity decreased to about 50% of initial activity at 37°C in 7 days.

Use of sweet sorghum juice for lipid production by Schizochytrium limacinum SR21

Stalk juice from sweet sorghum grown in Southern Illinois, USA, was examined for lipid production through microalgal fermentation. Juice concentrations at 100%, 75%, 50%, and 25% led to different biomass, lipid, and docosahexaenoic acid (DHA) production by Schizochytrium limacinum SR21. Biomass dry weight as 9.4 g/l at 50% juice concentration was similar to that from pure glucose (10.9 g/l). But with a 73.4% lipid content, this dose resulted in higher lipid and DHA production than those from pure glucose. Major fatty acids in cells grown on juice were identical to those fed by other substrates. Among the three sugars – glucose, fructose, and sucrose in sorghum juice, only glucose was utilized for growth. Spent medium after algal removal may be further processed for white sugar production in a traditional way since sucrose content remained the same throughout the algal fermentation process. Algal cells or lipids harvested can be utilized as fish meal, human nutrition supplements, or for biodiesel purpose.

Inactivity-mediated insulin resistance is associated with upregulated pro-inflammatory fatty acids in human cell membranes

Low-grade systemic inflammation and pro-inflammatory pattern of cell membrane fatty acid composition characterize patients affected by type 2 diabetes and metabolic syndrome. We hypothesize that inactivity-induced insulin resistance could affect levels of pro-inflammatory fatty acids in cell membranes. Thirty healthy, male, young volunteers were investigated before and after 35-day experimental bed rest. Diet composition was adapted to previous dietary habits. Fatty acid composition of erythrocyte membranes was analyzed by gas-chromatography using flame ionization detector. Following bed rest, the HOMA index of insulin resistance significantly increased by +51+/-11% (P<0.01). Bed rest was associated with increased n-6 polyunsaturated (+4.7+/-2.2%; P<0.01) and decreased monounsaturated (-4.8+/-1.5%; P<0.01) fatty acid content in erythrocyte membranes. Fractional content of arachidonic acid increased by +14+/-12% (P=0.01) following inactivity. Delta5 and Delta9 desaturase indexes, as estimated from product-to-precursor ratios, significantly diminished following bed rest from 9.6+/-0.4 to 8.4+/-0.3 (P<0.001) and from 0.72+/-0.02 to 0.69+/-0.01 (P<0.05), respectively. The n-3 fatty acids, alpha-linolenic and eicosapentaenoic, were decreased (P=0.05) following inactivity by 4.7+/-13.2% and 3.8+/-5.2%, respectively. Inactivity-mediated insulin resistance was associated with altered Delta5 and Delta9 desaturase indexes and with pro-inflammatory fatty acid pattern in erythrocyte membranes. These abnormalities could contribute to the low-grade inflammation associated to inactivity.