scholarly journals ASSEMBLY AND DYNAMICS OF MICROBIAL COMMUNITIES IN GRANULAR, FIXED-BIOFILM AND PLANKTONIC METHANOGENIC MICROBIOMES VALORIZING LONG CHAIN FATTY ACID (LCFA)-RICH WASTEWATER

2021 ◽  
Author(s):  
Suniti Singh ◽  
Johanna M. Rinta-Kanto ◽  
Piet N.L. Lens ◽  
Marika Kokkoa ◽  
Jukka Rintala ◽  
...  
Keyword(s):  
Community Dynamics ◽  
Long Chain Fatty Acids ◽  
Oil And Grease ◽  
Long Chain Fatty Acid ◽  
Loading Rates ◽  
Microbial Community Dynamics ◽  
Syntrophic Bacteria ◽  
Spatio Temporal ◽  
Long Chain ◽  
Fixed Biofilm

Distinct microbial assemblages are engineered in anaerobic digestion (AD) reactors to drive sequential conversions of organics to methane. The spatio-temporal development of three such assemblages (granules, biofilms, planktonic) derived from the same inoculum was studied in replicated bioreactors treating long-chain fatty acids (LCFA)-rich wastewater at 20C at hydraulic retention times (HRTs) of 12-72 h. We found granular, biofilm and planktonic assemblages differentiated by diversity, structure, and assembly mechanisms; demonstrating a spatial compartmentalisation of the microbiomes from the initial community reservoir. Our analysis linked abundant Methanosaeta and Syntrophaceae-affiliated taxa (Syntrophus and uncultured) to their putative, active roles in syntrophic LCFA bioconversion. LCFA loading rates (stearate, palmitate), and HRT, were significant drivers shaping microbial community dynamics and assembly. This study of the archaea and syntrophic bacteria actively valorising LCFAs at short HRTs and 20C will help uncover the microbiology underpinning anaerobic bioconversions of fats, oil and grease.

Metabolomic linkage reveals functional interaction between glucose-dependent insulinotropic polypeptide and ghrelin in humans

2011 ◽  
Vol 301 (4) ◽  
pp. E608-E617 ◽  
Author(s):  
Natalia N. Rudovich ◽  
Victoria J. Nikiforova ◽  
Baerbel Otto ◽  
Olga Pivovarova ◽  
Özlem Gögebakan ◽  
...  
Keyword(s):  
Molecular Mechanisms ◽  
Gastrointestinal Hormones ◽  
Plasma Metabolites ◽  
Long Chain Fatty Acids ◽  
Long Chain Fatty Acid ◽  
Insulin Levels ◽  
Systemic Control ◽  
Combining Data ◽  
Obese Subjects ◽  
Long Chain

The gastric peptide ghrelin promotes energy storage, appetite, and food intake. Nutrient intake strongly suppresses circulating ghrelin via molecular mechanisms possibly involving insulin and gastrointestinal hormones. On the basis of the growing evidence that glucose-dependent insulinotropic polypeptide (GIP) is involved in the control of fuel metabolism, we hypothesized that GIP and/or insulin, directly or via changes in plasma metabolites, might affect circulating ghrelin. Fourteen obese subjects were infused with GIP (2.0 pmol·kg−1·min−1) or placebo in the fasting state during either euglycemic hyperinsulinemic (EC) or hyperglycemic hyperinsulinemic clamps (HC). Apart from analysis of plasma ghrelin and insulin levels, GC-TOF/MS analysis was applied to create a hormone-metabolite network for each experiment. The GIP and insulin effects on circulating ghrelin were analyzed within the framework of those networks. In the HC, ghrelin levels decreased in the absence (19.2% vs. baseline, P = 0.028) as well as in the presence of GIP (33.8%, P = 0.018). Ghrelin levels were significantly lower during HC with GIP than with placebo, despite insulin levels not differing significantly. In the GIP network combining data on GIP-infusion, EC+GIP and HC+GIP experiments, ghrelin was integrated into hormone-metabolite networks through a connection to a group of long-chain fatty acids. In contrast, ghrelin was excluded from the network of experiments without GIP. GIP decreased circulating ghrelin and might have affected the ghrelin system via modification of long-chain fatty acid pools. These observations were independent of insulin and offer potential mechanistic underpinnings for the involvement of GIP in systemic control of energy metabolism.

scholarly journals Non-esterified Long-chain Fatty Acid Metabolism in Fed Sheep at Rest and During Exercise

1987 ◽  
Vol 40 (2) ◽  
pp. 221 ◽  
Author(s):  
DW Pethick ◽  
N Harman ◽  
JK Chong
Keyword(s):  
Skeletal Muscle ◽  
Ketone Bodies ◽  
Long Chain Fatty Acids ◽  
Entry Rate ◽  
Long Chain Fatty Acid ◽  
Pregnant Sheep ◽  
Arteriovenous Difference ◽  
Long Chain ◽  
Sustained Increase

The role of circulating, non-esterified, long-chain fatty acids (NEFA) as a source of energy for the whole animal and skeletal muscle was investigated in fed non-pregnant sheep at rest and during exercise. Infusion of tracer quantities of [1-14C]oleic or [l-14C]stearic acid was combined with the use of arteriovenous difference studies on fed sheep at rest or during a 2 h period of exercise on a belt treadmill moving at 4� 5 km h -I. At rest all parameters of NEFA metabolism indicated a minimal role for oxidation. Thus the concentration in plasma (0'07 � 0�01 mmol I-I), entry rate (0'08 � 0�02 mmol h- I kg-I body wt), contribution to whole animal oxidation (1'2 � 0'3%) and utilization of NEFA by skeletal muscle (0'046 � 0�008 mmol h- I kg-I muscle) were all low. Exercise prompted a shift to lipolysis and accordingly the above parameters increased markedly some 13-24-fold. The circulating concentration of ketone bodies showed only a small increase during exercise and consequently the role of ketone bodies as an energy source during exercise was minimal. Glucose utilization by skeletal muscle was considerable in animals at rest and it represented the most significant potential fuel of skeletal muscle. Exercise resulted in a sustained increase of 3-4-fold in the utilization of glucose by skeletal muscle. Thus the traditional view that NEF A and not glucose is a predominant fuel of skeletal muscle of fed sheep should be appraised.

Triacylglycerol: an important pool of essential fatty acids during early postnatal development in rats

1992 ◽  
Vol 262 (1) ◽  
pp. R8-R13 ◽  
Author(s):  
S. C. Cunnane ◽  
Z. Y. Chen
Keyword(s):  
Fatty Acids ◽  
Essential Fatty Acids ◽  
Fatty Acid Content ◽  
Whole Body ◽  
Long Chain Fatty Acids ◽  
Long Chain Fatty Acid ◽  
Early Postnatal Development ◽  
Major Organ ◽  
Long Chain ◽  
Chain Fatty Acids

Developmental changes in the content and composition of major organ lipid pools are not well known. Our objective was to assess quantitatively the changes in lipids, particularly those containing long-chain fatty acids, in the placenta and the brain, liver, and carcass of the fetal and suckling rat. Pregnant dams were killed at days 15, 18, and 21 (term) of pregnancy and the placentas and fetuses removed and analyzed; suckling rats were killed at days +3, +6, and +9 of lactation. Whereas the long-chain fatty acid content of the phospholipids (mg/g) of the fetal or suckling rat remained relatively constant from day 18 of pregnancy to day +9 of lactation, long-chain fatty acids in triacylglycerols increased from prenatal values by 10- to 12-fold during the first 9 postnatal days. Prenatally, triacylglycerol accounted for no more than 32% of total whole body essential fatty acids (day 21), but postnatally this increased to 81-88%. From day 21 to day +9, the proportion of n-6 and n-3 essential fatty acids within the total triacylglycerol pool of the suckling rat increased 71 and 317%, respectively. We conclude that in the suckling rat, triacylglycerol is quantitatively the most important source of essential fatty acids during at least the first 9 days of life.

The Very-Long-Chain Fatty Acid Synthase Is Inhibited by Chloroacetamides

2004 ◽  
Vol 59 (7-8) ◽  
pp. 549-553 ◽  
Author(s):  
Thomas Götz ◽  
Peter Böger
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Fatty Acid Synthase ◽  
Chain Fatty Acid ◽  
Long Chain Fatty Acids ◽  
Irreversible Binding ◽  
Long Chain Fatty Acid ◽  
Malonyl Coa ◽  
Elongation Step ◽  
Long Chain

AbstractThe first elongation step to form very-long-chain fatty acids (VLCFAs) is catalyzed by the VLCFA-synthase. CoA-activated fatty acids react with malonyl-CoA to condense a C2-unit. As shown with recombinant enzyme this reaction is specifically inhibited by chloroacetamide herbicides. The inhibition is alleviated when the inhibitor (e.g. metazachlor) is incubated together with adequate concentrations of the substrate (e.g. oleoyl-CoA). Malonyl-CoA has no influence. However, once a chloroacetamide has been tightly bound to the synthase after an appropriate time it cannot be displaced anymore by the substrate. In contrast, oleoyl- CoA, is easily removed from the synthase by metazachlor. The irreversible binding of the chloroacetamides and their competition with the substrate explains the very low half-inhibition values of 10-8 м and below. Chiral chloroacetamides like metolachlor or dimethenamid give identical results. However, only the (S)-enantiomers are active.

The effect of a blend of dietary unesterified and saturated long-chain fatty acids on the performance of dairy cows in mid-lactation

1990 ◽  
Vol 41 (1) ◽  
pp. 129 ◽  
Author(s):  
KR King ◽  
CR Stockdale ◽  
TE Trigg
Keyword(s):  
Fatty Acids ◽  
Fatty Acid ◽  
Dairy Cows ◽  
Milk Fat ◽  
Chain Fatty Acid ◽  
Long Chain Fatty Acids ◽  
Long Chain Fatty Acid ◽  
Long Chain ◽  
Chain Fatty Acids

This experiment studied the effects of feeding a supplement of a blend of unesterified and saturated long-chain fatty acids on the productivity of dairy cows in mid-lactation. Twenty-three cows in their fourth month of lactation were individually fed ad libitum, a mixed balanced ration based on maize silage, lucerne hay and rolled grain. Varying quantities, up to 1020 g cow-1 day-1 of the fatty acid supplement, were mixed into the ration. Yields of milk and milk products were linearly related to total long-chain fatty acid intake. Milk fat content increased linearly while milk protein content averaged 3.59 (s.d. � 0.15)%. The marginal returns from feeding 1 kg of the supplement were 3.3 kg milk, 0.33 kg fat and 0.07 kg protein. The proportions of C 10:0, C12:0 and C 14:0 fatty acids in milk were decreased, while those of C 18:0 and C18:1 were increased as the result of feeding long-chain fatty acids. The concentration of lipid in plasma was increased, but acetate and D-(3)-hydroxybutyrate levels in blood remained unchanged with increased levels of dietary long-chain fatty acid. Efficiency of milk production was increased by 11% from feeding 1 kg of the supplement. In vivo digestibilities of dry matter, neutral and acid detergent fibres, and dietary long-chain fatty acids were unaffected by supplement.

scholarly journals The effect of intracellular pH on long-chain fatty acid uptake in 3T3-L1 adipocytes: evidence that uptake involves the passive diffusion of protonated long-chain fatty acids across the plasma membrane

1996 ◽  
Vol 313 (2) ◽  
pp. 487-494 ◽  
Author(s):  
Bernardo L. TRIGATTI ◽  
Gerhard E. GERBER
Keyword(s):  
Fatty Acids ◽  
Plasma Membrane ◽  
Fatty Acid ◽  
Chain Fatty Acid ◽  
Long Chain Fatty Acids ◽  
Cytoplasmic Ph ◽  
Long Chain Fatty Acid ◽  
Intact Cells ◽  
Fatty Acid Binding ◽  
Long Chain

To understand the mechanism of long-chain fatty acid permeation of the plasma membrane in mammalian cells, the effects of changes in the cytoplasmic pH on the internalization of physiologically relevant, submicromolar concentrations of uncomplexed long-chain fatty acids were investigated in 3T3-L1 adipocytes. The acidification of the cytoplasm upon NH4Cl prepulsing of intact cells was accompanied by a rapid reduction of cellular long-chain fatty acid uptake (measured as the total accumulation of [9,10-3H]oleate). This was followed by a slow recovery to normal levels of uptake as the cytoplasmic pH recovered. Conventional filtration assays do not distinguish between fatty acid movement across the plasma membrane and intracellular steps, such as binding to cytoplasmic fatty acid-binding proteins or metabolism. While the in vitro binding of a photoreactive fatty acid, 11-m-diazirinophenoxy[11-3H]undecanoate, to a cytoplasmic fatty acid-binding protein was insensitive to changes in pH from pH 7.5 to 5.5, the in vitro conversion of oleate into oleoyl-CoA by cellular acyl-CoA synthetase decreased dramatically. Therefore, the labelling of the 15 kDa cytoplasmic fatty acid-binding protein in intact cells by the photoreactive fatty acid was used as a more direct measure of the permeation of the probe across the plasma membrane. Acidification of the cytoplasm resulted in an immediate reduction in the labelling of this protein in intact adipocytes. Its photolabelling recovered, however, upon the recovery of the cytoplasmic pH to normal levels. This was due to effects of the cytoplasmic pH on the permeation of the photoreactive fatty acid across the plasma membrane rather than its binding to the 15 kDa protein or metabolism in vivo. This is the first demonstration that the movement of physiologically relevant, submicromolar concentrations of uncomplexed long-chain fatty acids across the plasma membrane of intact cells is coupled to the cytoplasmic pH and suggests that it occurs by the diffusion of the protonated long-chain fatty acid through the lipid bilayer.

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