Transport systems for organic acids induced in the marine pennate diatom, Cylindrotheca fusiformis

1972 ◽  
Vol 18 (2) ◽  
pp. 225-233 ◽  
Author(s):  
Johan A. Hellebust ◽  
Joyce Lewin
Keyword(s):  
Organic Acids ◽  
Dicarboxylic Acids ◽  
Metabolic Inhibitors ◽  
Transport Systems ◽  
Complex Relationship ◽  
Temperature Dependent ◽  
Pennate Diatom ◽  
Cylindrotheca Fusiformis ◽  
Uptake Rates ◽  
Marine Littoral

Cells of Cylindrotheca fusiformis, a marine littoral pennate diatom, can be induced to take up lactate by merely keeping them in the dark, and to take up succinate, fumarate, and malate as well as lactate by keeping them in the dark in the presence of any of these organic acids. Studies of uptake rates as a function of substrate concentration show a complex relationship indicating the presence of two or more uptake systems for any of these organic acids, each having different affinities and capacities for the substrates. Growth rate also shows a similar complex relationship to substrate concentration.Competition experiments indicate that lactate is taken up by different transport systems from those serving the 4-carbon dicarboxylic acids. Pyruvate is not taken up by C. fusiformis. Correlation of activities of enzymes involved in the immediate assimilation of the organic acids with the presence or absence of the ability to take up these substrates by cells incubated under different conditions show that the necessary assimilatory enzymes are already present and that it is rather the transport systems that are induced. The presence of glucokinase in dark-grown cells indicates that the inability of the cells to take up glucose is due to the lack of induction of a glucose transport system.The metabolic inhibitors dinitrophenol and iodoacetate inhibit the uptake of organic acids. However, since under normal conditions the organic acids are rapidly converted to other metabolites upon entry into the cells, and do not appear to accumulate, the observed inhibition may be at the level of assimilation rather than transport. The uptake of lactate and succinate is temperature dependent with a Q10 of 1.5–1.7, but is almost unaffected by changes in salinity from 10 to 150% of normal seawater. The relation between pH and rates of uptake of lactate and succinate suggests that the completely dissociated form of the organic acids is transported.

Heterotrophic nutrition of the marine pennate diatom, Cylindrotheca fusiformis

1970 ◽  
Vol 16 (11) ◽  
pp. 1123-1129 ◽  
Author(s):  
Joyce Lewin ◽  
Johan A. Hellebust
Keyword(s):  
Organic Compounds ◽  
Generation Time ◽  
Organic Substrate ◽  
Pennate Diatom ◽  
Cylindrotheca Fusiformis ◽  
Lag Period ◽  
Light Generation ◽  
Casamino Acids ◽  
High Concentrations ◽  
Marine Littoral

Cylindrotheca fusiformis Reimann & Lewin, a marine littoral pennate diatom, can grow in the dark in media containing an organic substrate. Lactate, succinate, fumarate, malate, Tryptone, Casamino Acids, or Yeast Extract can serve as substrate. Glucose apparently cannot be used for heterotrophic growth. Cells taken from the light and used as inoculum for dark cultures began to multiply after a lag period; its length depends on the substrate concentration.Experiments with radioactively labeled organic compounds confirmed the growth experiments. C. fusiformis did not take up significant amounts of 14C-labeled alanine, glutamic acid, aspartic acid, acetate, or glucose, even after several days of preincubation in the dark with high concentrations of these compounds. Cells kept in the dark in the absence of organic compounds developed a capacity to take up lactate, but not succinate. Cells grown in the dark in the presence of lactate were able subsequently to take up radioactively labeled succinate as well as lactate.The generation time under optimum conditions in the dark was around 30 h, longer than for cells growing autotrophically in the light (generation time 12.5 h at 2000 lux). The pigment composition of dark-grown cells was similar to that of light-grown cultures, except that diadinoxanthin was not detectable in the dark-grown cells. Chromatophore structure in dark-grown cells was normal. Cells brought into the light after being cultured in the dark for 3 weeks evolved oxygen immediately upon illumination. C. fusiformis did not multiply under anaerobic conditions in the dark but could survive under these conditions for at least 2 months.

INFLUENCE OF DICARBOXYLIC ACIDS ON SOWING QUALITY OF SPRING BARLEY

1970 ◽  
pp. 22-25
Author(s):  
N. N. Loy ◽  
S. N. Gulina
Keyword(s):  
Organic Acids ◽  
Spring Barley ◽  
Dose Range ◽  
Dicarboxylic Acids ◽  
Rotary Machine ◽  
Working Solution ◽  
Negative Effect ◽  
Sprouted Seeds

The effect of presowing seed treatment on various concentrations of dicarboxylic (organic) acids on the sowing characteristics of spring barley has been studied. Seeds were treated with organic acids obtained by exposing cuttings to the radiation with a dose of 100 kGy and consequent hydrolysis, in concentrations: 1•10-7 %; 1•10-9; 1•10-11; 1•10-13 and 1•10-15 % on a laboratory rotary machine RVO-64 for one day before laying for germination. Distilled water was used for the control case. The rate of application of the working solution calculated as 10 liters / ton of seeds. Seeds were germinated in filter paper rolls in accordance with GOST 12038-84 requirements. The temperature was maintained at +24 ° C in the thermostat where the glasses with rolls were placed. For determination of germinative power and laboratory germination the sprouted seeds were evaluated after three and seven days, respectively. In laboratory experiments it was established that the treatment of barley seeds of varieties Zazersky 85, Nur and Vladimir with organic acids (OK) in different concentrations had both a stimulating and a negative effect. On the Zazersky 85 variety, in variants with acid concentrations of 1•10-9 and 1•10-11, an increase in germination energy (EP) by 2-4% and a significant decrease (by 3-4%) of laboratory germination (LV) of barley seeds were noted. On the Nur variety, the increase in EP was observed at 4% (concentration 1•10-11), LV and seed growth force (CPC) by 2-7% at a concentration of 1•10-7 and in the dose range 1•10-11 - 1•10-14 compared to the control values. On the grade of Vladimir, an increase in EP, LV, and CPC was found to increase by 1-6% at concentrations OK 1•10-7 and 1•10-13. It was shown that the treatment of seeds with acids led to an increase in the length of the germ in all studied varieties (by 3-9%) and dry biomass of 7-day-old seedlings - by 3-6%. Consequently, the treatment of seeds with a mixture of dicarboxylic acids has a stimulating effect on the sowing quality of spring barley.

P-glycoprotein-mediated secretion of a fluorescent cyclosporin analogue by teleost renal proximal tubules

1995 ◽  
Vol 268 (1) ◽  
pp. F46-F52 ◽  
Author(s):  
U. Schramm ◽  
G. Fricker ◽  
R. Wenger ◽  
D. S. Miller
Keyword(s):  
Steady State ◽  
Fluorescence Intensity ◽  
Fundulus Heteroclitus ◽  
Organic Anion ◽  
Proximal Tubules ◽  
Metabolic Inhibitors ◽  
Epifluorescence Microscopy ◽  
Transport Systems ◽  
Simple Diffusion ◽  
P Glycoprotein

The transport of a fluorescent cyclosporin analogue was measured in killifish (Fundulus heteroclitus) proximal tubules by means of epifluorescence microscopy and digital image analysis. Renal cells rapidly accumulated the cyclosporin analogue from the medium and attained steady state within 60 min; luminal fluorescence increased over the first 60-90 min. At steady state, luminal fluorescence intensity was two to three times higher than cellular. Cellular fluorescence intensity was a linear function of medium substrate concentration and was not affected by any treatment used. In contrast, luminal fluorescence exhibited a saturable component as the medium concentration of the cyclosporin was increased. Secretion into the lumen was blocked by metabolic inhibitors, vanadate, other cyclosporins, such as cyclosporin A and cyclosporin G, and substrates for P-glycoprotein (verapamil, vinblastine, and quinine) but not by substrates for the renal organic anion or organic cation transport systems, such as p-aminohippurate or tetraethylammonium. The data are consistent with the fluorescent cyclosporin analogue entering proximal tubule cells by simple diffusion and then being pumped into the tubular lumen by P-glycoprotein.

scholarly journals Vertical distribution of particle-phase dicarboxylic acids, oxoacids and α-dicarbonyls in the urban boundary layer based on the 325-meter tower in Beijing

2020 ◽  
Author(s):  
Wanyu Zhao ◽  
Hong Ren ◽  
Kimitaka Kawamura ◽  
Huiyun Du ◽  
Xueshun Chen ◽  
...  
Keyword(s):  
Boundary Layer ◽  
Oxalic Acid ◽  
Vertical Distribution ◽  
Organic Acids ◽  
Anthropogenic Activities ◽  
Ground Surface ◽  
Dicarboxylic Acids ◽  
Ground Level ◽  
Water Soluble ◽  
Motor Vehicles

Abstract. Vertical distribution of dicarboxylic acids, oxoacids, α-dicarbonyls, and other organic tracer compounds in fine aerosols (PM2.5) was investigated from the ground surface (8 m) to 260 m at a 325-meter meteorological tower in Beijing in the summer of 2015. Results showed that the concentrations of oxalic acid (C2), the predominant diacid, were more abundant at 120 m (210 ± 154 ng m−3) and 260 m (220 ± 140 ng m−3) than those at the ground level (160 ± 90 ng m−3). Concentrations of phthalic acid (Ph) decreased with the increase of heights, demonstrating that the vehicular exhausts at the ground surface was the main contributor. Positive correlations were noteworthy for C2/total diacids with mass ratios of C2 to main oxoacids (Pyr, ωC2) and α-dicarbonyls (Gly, MeGly) in polluted days (0.42 ≤ r2 ≤ 0.65), especially at the ground level. In clean days, the ratios of carbon content in oxalic acid to water soluble organic carbon (C2-C/WSOC) showed larger values at 120 m and 260 m than those at the ground surface. However, in polluted days, the C2-C/WSOC ratio mainly reached its maximum at the ground level. These phenomena may indicate the enhanced contribution of aqueous-phase oxidation to oxalic acid in polluted days. Combined with the influence of wind field, total diacids, oxoacids and α-dicarbonyls decreased by 22 %–58 % under the control on anthropogenic activities during the 2015 Victory Parade period. Furthermore, the PMF results showed that the secondary formation routes (secondary sulfate formation and secondary nitrate formation) were the dominant contributors (37–44 %) to organic acids, followed by biomass burning (25–30 %) and motor vehicles (18–24 %). In this study, the organic acids at the ground level were largely associated with local traffic emissions, while the long-range atmospheric transport followed by photochemical aging contributed more to diacids and related compounds in the boundary layer over Beijing than the ground surface.

Copper, nickel, and thallium uptake by the lichen Cladina rangiferina

1981 ◽  
Vol 59 (1) ◽  
pp. 91-100 ◽  
Author(s):  
M. A. S. Burton ◽  
P. LeSueur ◽  
K. J. Puckett
Keyword(s):  
Metal Uptake ◽  
Deionized Water ◽  
Metabolic Inhibitors ◽  
Temperature Dependent ◽  
Low Concentrations ◽  
Nickel Uptake ◽  
High Concentrations ◽  
Uptake Studies ◽  
Cladina Rangiferina ◽  
Very High

Metal uptake studies with Cladina rangiferina showed that the affinity for nickel was much lower than for copper or thallium. Nickel uptake was not decreased by the absence of light or oxygen or by pretreatment with metabolic inhibitors. Nickel uptake was not temperature dependent but was very dependent upon pH.Cation-exchange studies demonstrated that there was a stoichiometric exchange of Ni2+ for Sr2+, and Cu2+ for Sr2+. The exchange of Tl+ for Sr2+ was not stoichiometric, excess Tl+ was accumulated in relation to the Sr2+ released. The ratio of Sr2+:Tl+ exchange increased with increasing Tl+ availability from 1:9 (12.5 μmol Tl+ available/g of lichen) to 1:2 (500 μmol Tl+ available). Acid-treated lichen gave the expected exchange ratio of 1:2. Washing of the thalli with deionized water resulted in the continued loss of Tl+ from acid-treated and live C. rangiferina. Copper and nickel were not released in this manner.Increasing concentrations of copper and thallium produced a corresponding loss of potassium from the thallus. The potassium loss was initiated at low concentrations of copper and thallium whereas very high concentrations of manganese and nickel were required to bring about the same response.

Heterotrophic potential of Phormidium and other blue-green algae

1974 ◽  
Vol 52 (11) ◽  
pp. 2369-2374 ◽  
Author(s):  
Daniel H. Pope
Keyword(s):  
Organic Compounds ◽  
Green Algae ◽  
Phaeodactylum Tricornutum ◽  
Metabolic Inhibitors ◽  
Blue Green Algae ◽  
Free Sample ◽  
Uptake Rates ◽  
Axenic Cultures ◽  
Marine Algal ◽  
Olive Green

Several algal types were tested for the ability to assimilate a variety of organic compounds including glucose, sucrose, glycerol, acetate, and a variety of amino acids. Axenic cultures of Phaeodactylum tricornutum, Cricosphaera sp., and Dunaliella tertiolecta failed to take up any of the compounds tested. Axenic cultures of the filamentous blue-green algae Phormidium sp. and Lyngbya sp. took up all of the test substrates, as did the "olive-green cells" (a non-bacteria-free sample of marine algal cells described as olive-green cells by other workers). The results of experiments to determine uptake rates over the range 10−7 to 10−3 molar substrate, rates of uptake at 18, 24, and 32C, and rates of uptake in the presence of the metabolic inhibitors dinitrophenol (DNP) and carbanyl cyanide m-chlorophenylhydrazone (CCCP) indicated that uptake of the organic compounds tested by the filamentous blue-green algae tested is not by an active transport mechanism.

Clathrin-mediated endocytosis of FITC-albumin in alveolar type II epithelial cell line RLE-6TN

2006 ◽  
Vol 290 (5) ◽  
pp. L946-L955 ◽  
Author(s):  
Ryoko Yumoto ◽  
Hiromi Nishikawa ◽  
Miho Okamoto ◽  
Hirokazu Katayama ◽  
Junya Nagai ◽  
...  
Keyword(s):  
Epithelial Cells ◽  
Laser Scanning ◽  
Metabolic Inhibitors ◽  
Transport Systems ◽  
Confocal Laser ◽  
Cytokeratin 19 ◽  
Epithelial Cell Line ◽  
Alveolar Type ◽  
Dependent Manner ◽  
Type Ii

We examined mechanisms of FITC-albumin uptake by alveolar type II epithelial cells using cultured RLE-6TN cells. Alkaline phosphatase activity and the expression of cytokeratin 19 mRNA, which are characteristic features of alveolar type II epithelial cells, were detected in RLE-6TN cells. The uptake of FITC-albumin by the cells was time and temperature dependent and showed the saturation kinetics of high- and low-affinity transport systems. FITC-albumin uptake was inhibited by native albumin, by chemically modified albumin, and by metabolic inhibitors and bafilomycin A1, an inhibitor of vacuolar H+-ATPase. Confocal laser scanning microscopic analysis after FITC-albumin uptake showed punctate localization of fluorescence in the cells, which was partly localized in lysosomes. FITC-albumin taken up by the cells gradually degraded over time, as shown by fluoroimage analyzer after SDS-PAGE. The uptake of FITC-albumin by RLE-6TN cells was not inhibited by nystatin, indomethacin, or methyl-β-cyclodextrin (inhibitors of caveolae-mediated endocytosis) but was inhibited by phenylarsine oxide and chlorpromazine (inhibitors of clathrin-mediated endocytosis) in a concentration-dependent manner. Uptake was also inhibited by potassium depletion and hypertonicity, conditions known to inhibit clathrin-mediated endocytosis. These results indicate that the uptake of FITC-albumin in cultured alveolar type II epithelial cells, RLE-6TN, is mediated by clathrin-mediated but not by caveolae-mediated endocytosis, and intracellular FITC-albumin is gradually degraded in lysosomes. Possible receptors involved in this endocytic system are discussed.

scholarly journals Concentrations of higher dicarboxylic acids C<sub>5</sub>–C<sub>13</sub> in fresh snow samples collected at the High Alpine Research Station Jungfraujoch during CLACE 5 and 6

2009 ◽  
Vol 9 (6) ◽  
pp. 2097-2112 ◽  
Author(s):  
R. Winterhalter ◽  
M. Kippenberger ◽  
J. Williams ◽  
E. Fries ◽  
K. Sieg ◽  
...  
Keyword(s):  
Organic Acids ◽  
Phthalic Acid ◽  
Dicarboxylic Acids ◽  
Back Trajectory ◽  
Research Station ◽  
Air Mass ◽  
Median Concentration ◽  
Fresh Snow ◽  
Alpine Research ◽  
Snow Samples

Abstract. Samples of freshly fallen snow were collected at the high alpine research station Jungfraujoch (Switzerland) in February and March 2006 and 2007, during the Cloud and Aerosol Characterization Experiments (CLACE) 5 and 6. In this study a new technique has been developed and demonstrated for the measurement of organic acids in fresh snow. The melted snow samples were subjected to solid phase extraction and resulting solutions analysed for organic acids by HPLC-MS-TOF using negative electrospray ionization. A series of linear dicarboxylic acids from C5 to C13 and phthalic acid, were identified and quantified. In several samples the biogenic acid pinonic acid was also observed. In fresh snow the median concentration of the most abundant acid, adipic acid, was 0.69 μg L−1 in 2006 and 0.70 μg L−1 in 2007. Glutaric acid was the second most abundant dicarboxylic acid found with median values of 0.46 μg L−1 in 2006 and 0.61 μg L−1 in 2007, while the aromatic acid phthalic acid showed a median concentration of 0.34 μg L−1 in 2006 and 0.45 μg L−1 in 2007. The concentrations in the samples from various snowfall events varied significantly, and were found to be dependent on the back trajectory of the air mass arriving at Jungfraujoch. Air masses of marine origin showed the lowest concentrations of acids whereas the highest concentrations were measured when the air mass was strongly influenced by boundary layer air.

scholarly journals Membrane transporters in the bioproduction of organic acids: state of the art and future perspectives for industrial applications

2020 ◽  
Vol 367 (15) ◽  
Author(s):  
I Soares-Silva ◽  
D Ribas ◽  
M Sousa-Silva ◽  
J Azevedo-Silva ◽  
T Rendulić ◽  
...  
Keyword(s):  
Plasma Membrane ◽  
Organic Acids ◽  
State Of The Art ◽  
Biomass Conversion ◽  
Current Trend ◽  
Dicarboxylic Acids ◽  
Cost Effective ◽  
Industrial Applications ◽  
Industrial Biotechnology ◽  
Extracellular Medium

ABSTRACT Organic acids such as monocarboxylic acids, dicarboxylic acids or even more complex molecules such as sugar acids, have displayed great applicability in the industry as these compounds are used as platform chemicals for polymer, food, agricultural and pharmaceutical sectors. Chemical synthesis of these compounds from petroleum derivatives is currently their major source of production. However, increasing environmental concerns have prompted the production of organic acids by microorganisms. The current trend is the exploitation of industrial biowastes to sustain microbial cell growth and valorize biomass conversion into organic acids. One of the major bottlenecks for the efficient and cost-effective bioproduction is the export of organic acids through the microbial plasma membrane. Membrane transporter proteins are crucial elements for the optimization of substrate import and final product export. Several transporters have been expressed in organic acid-producing species, resulting in increased final product titers in the extracellular medium and higher productivity levels. In this review, the state of the art of plasma membrane transport of organic acids is presented, along with the implications for industrial biotechnology.

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