Biosynthèse des glycoconjugués pulmonaires. III. Mannosylation des accepteurs lipidiques et protéiniques

1979 ◽  
Vol 57 (9) ◽  
pp. 1163-1169 ◽  
Author(s):  
Christiane Levrat ◽  
Pierre Louisot
Keyword(s):  
Low Temperature ◽  
Thin Layer ◽  
Kinetic Studies ◽  
The Other ◽  
Enzymatic System ◽  
Dilute Acid ◽  
Trichloracetic Acid ◽  
Pig Liver ◽  
Layer Chromatography ◽  
O 10

Earlier studies on the biosynthesis of mannosyl glycoproteins in microsomes of rat lungs have been extended to show that a mannosyltransferase was able to catalyze the incorporation of mannose from GDP-mannose. In sheep lungs, we have shown that a mannosyltransferase activity is involved at microsomal level This enzymatic system is able to catalyze the incorporation of mannose from GDP-mannose into three different endogenous acceptors. The enzymatic products are as follows: a mannolipid (product A) extracted with CHCl3–CH3OH (2:1), mannose is also incorporated into a product B extracted with CHCl3-CH3OH–H2O (10:10:3), and into another product C insoluble in water and precipitable in trichloracetic acid. The kinetic studies of product biosynthesis suggest that there does not exist a precursor–product relationship. The product A is synthesized in larger quantities than the products B and C. Exogenous dolichoi-monophosphate stimulates the incorporation of [14C]mannose into mannolipid (product A) only. The results indicate that the mannolipid (product A) is not an intermediate in the transfer of mannose from GDP-mannose to the other products (B and C). The product A of the reaction, the mannolipid, has the properties of a polyprenyl-phosphoryl-mannose. This is illustrated by its lability to dilute acid but stability to dilute alkali at low temperature, and by its mobility on thin layer chromatography. However, this product A is not similar to dolichyl-monophosphoryl-mannose from pig liver.

Analysis of Ochratoxins A and B and Their Esters in Barley, Using Partition and Thin Layer Chromatography. II. Collaborative Study

1973 ◽  
Vol 56 (4) ◽  
pp. 822-826
Author(s):  
Stanley Nesheim
Keyword(s):  
Thin Layer ◽  
Ochratoxin A ◽  
Coefficient Of Variation ◽  
Collaborative Study ◽  
Ethyl Esters ◽  
The Other ◽  
Average Recovery ◽  
Confirmation Test ◽  
Two Samples ◽  
Layer Chromatography

Abstract To test the method of Nesheim et al., 6 samples wert; analyzed in 13 laboratories. The samples encompassed a blank and 5 samples containing one or more ochratoxins in the range 50–200 μg/kg. Two samples were spiked with the 4 ochratoxin standards and 3 were spiked with barley naturally contaminated with ochratoxin A. The confirmation of identity of ochratoxins A and B by preparation of their ethyl ester derivatives was also tested. The average recovery of standard ochratoxin A was 112% at levels of 45 and 90 μg/kg, with a 27.1% coefficient of variation calculated from analysis of variance, one analyst, one replicate. Similar satisfactory results were obtained for the ethyl esters of A and B at a level of 120 μg/kg. The results were unsatisfactory for ochratoxin B and for the esters of A and B at the 60 μg/kg level. The chemical confirmation test was satisfactory for both ochratoxins A and B. The method, including chemical confirmation, has been adopted as official first action as quantitative for ochratoxin A and qualitative for the other toxins.

Sugar-meal sources used by female black flies (Diptera: Simuliidae): a four-habitat study

1997 ◽  
Vol 75 (7) ◽  
pp. 1066-1072 ◽  
Author(s):  
Steven G. Burgin ◽  
Fiona F. Hunter
Keyword(s):  
Thin Layer ◽  
Thin Layer Chromatography ◽  
The Other ◽  
Black Flies ◽  
Layer Chromatography ◽  
Provincial Park

Adult black flies were sampled by sweep-netting vegetation in four habitats within Algonquin Provincial Park, Ontario: Davies Bog, the airfield, deciduous habitat, and coniferous habitat. Sugars in the crops and midguts of female flies (n = 773) were tested by thin-layer chromatography to determine whether the flies had fed on nectar or homopteran honeydew. Melezitose and stachyose were used as honeydew-indicator sugars. For Simulium venustum, it was found that significantly fewer black flies (19%) from the airfield contained honeydew sugars than black flies from the other three sites (34% from Davies Bog; 36% from deciduous habitat; 25% from coniferous habitat). We argue that black flies will feed on nectar or honeydew according to availability.

scholarly journals 5α-Androstane-3α,17β-Diol Is Formed in Tammar Wallaby Pouch Young Testes by a Pathway Involving 5α-Pregnane-3α,17α-Diol-20-One as a Key Intermediate

Endocrinology ◽  
2003 ◽  
Vol 144 (2) ◽  
pp. 575-580 ◽  
Author(s):  
Jean D. Wilson ◽  
Richard J. Auchus ◽  
Michael W. Leihy ◽  
Oleg L. Guryev ◽  
Ronald W. Estabrook ◽  
...  
Keyword(s):  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Reductase Inhibitor ◽  
Tammar Wallaby ◽  
The Other ◽  
Synthetic Pathway ◽  
D 20 ◽  
17 Hydroxyprogesterone ◽  
Layer Chromatography

The synthetic pathway by which 5α-androstane-3α,17β-diol (5α-adiol) is formed in the testes of tammar wallaby pouch young was investigated by incubating testes from d 20–40 males with various radioactive precursors and analyzing the metabolites by thin-layer chromatography and HPLC. [3H]Progesterone was converted to 17-hydroxyprogesterone, which was converted to 5α-adiol by two pathways: One involves the formation of testosterone and dihydrotestosterone as intermediates, and the other involves formation of 5α-pregnane-3α,17α-diol-20-one (5α-pdiol) and androsterone as intermediates. Formation of 5α-adiol from both [3H]testosterone and [3H]progesterone was blocked by the 5α-reductase inhibitor 4MA. The addition of nonradioactive 5α-pdiol blocked the conversion of [3H]progesterone to 5α-adiol, and [3H]5α-pdiol was efficiently converted to androsterone and 5α-adiol. We conclude that expression of steroid 5α-reductase in the developing wallaby testes allows formation of 5α-reduced androgens by a pathway that does not involve testosterone as an intermediate.

scholarly journals Determination of conversion rate values to characterise the ethanol production of the Kluyveromyces marxianus CBS712 fungus branch

2010 ◽  
pp. 23-27
Author(s):  
Éva Erdei ◽  
István Pócsi ◽  
Mónika Molnár ◽  
Gyöngyi Gyémánt ◽  
János Nagy
Keyword(s):  
Thin Layer ◽  
Ethanol Production ◽  
Kluyveromyces Marxianus ◽  
Conversion Rate ◽  
The Other ◽  
Conversion Rates ◽  
Residual Glucose ◽  
Oxidase Enzyme ◽  
Layer Chromatography

The ethanol production of the Kluyveromyces marxianus CBS712 strain was investigated among different kind of condition. We defined the conversion rate in order to know the efficiency of the ethanol production. To determine this value, it is crucial to characterize the residual glucose concentracio. We chose two method to determine the amount of residual glucose. The first method is the thin layer chromatography (TLC) and the second method is the method of the glucose-oxidase enzyme. We found that the TLC method is reliable than the other method. The conversion rates were determined from these values and the ethanol values. The maximal ethanol production of the characterized Kluyveromyces marxianus CBS712 strain (5.6% (v/v) ethanol at 45 °C, 55.3% conversion rate) is comparable to those strains which are applied in industrial ethanol production nowadays.

Platelet Factor 3 Activity in Washed Platelets

1973 ◽  
Vol 30 (03) ◽  
pp. 557-566 ◽  
Author(s):  
S Renaud ◽  
P Gautheron ◽  
H Rosenstein
Keyword(s):  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Platelet Rich Plasma ◽  
The Other ◽  
Slow Speed ◽  
Platelet Factor ◽  
Platelet Poor Plasma ◽  
Platelet Counts ◽  
Edta Solution ◽  
Layer Chromatography

SummaryPlatelets collected with an EDTA solution and simply washed in an incomplete Tyrode’s presented clotting times in the recalcification (man and rat) and the Stypven (rat) tests that were practically identical to those of the PRP when slow speed centrifugation was used (800 G in man, 1000 G in rat). This was demonstrated, in 6 pools of 5 rats each and in 6 men, by comparing the clotting activity of the citrated platelet-rich plasma to that of the platelets washed and resuspended in the citrated platelet-poor plasma, for platelet counts ranging from 1 × 105 to 10 × 105/mm3. In contrast, centrifugation of platelets at 3000 G markedly affected these clotting activities, as was shown in an additional study comprising 6 pools of 3 rats.Finally, the clotting activity of platelets totally disrupted by sonication appears to be identical quantitatively in both man and rats to that of the total phospholipids extracted from these platelets and separated from the other lipids by thin-layer chromatography and resuspended in plasma by sonication.

EXCRETION OF BILE ACIDS BY THREE MEN ON A FAT-FREE DIET

1966 ◽  
Vol 44 (6) ◽  
pp. 957-969 ◽  
Author(s):  
S. S. Ali ◽  
A. Kuksis ◽  
J. M. R. Beveridge
Keyword(s):  
Liquid Chromatography ◽  
Thin Layer ◽  
Bile Acids ◽  
The Other ◽  
Total Output ◽  
Gas Liquid Chromatography ◽  
Fecal Bile Acids ◽  
Layer Chromatography ◽  
Total Excretion

A combination of thin-layer chromatography and gas–liquid chromatography was used for the separation and determination of fecal bile acids in three middle-aged men during the last 4 days of three 8-day periods on a fat-free diet. The range of the total output was 130–650 mg/day. Lithocholic and deoxycholic acids were the major components and accounted for 65–80% of the total excretion of bile acids. Other common bile acids were present in considerably smaller quantities (0.5–11% each). In addition, evidence was obtained for the presence of a number of as yet unreported fecal bile acids. These were tentatively identified as 3α,12β-dihydroxy-, 3β,12β-dihydroxy-, 3α,7β-dihydroxy-, 3α-monohydroxy-7-keto-, 12α-monohydroxy-3-keto-, and 7β-monohydroxy-cholanic and cholanic acids. The latter three acids occurred in traces only, but the other uncommon fecal bile acids each accounted for 0.5–7% of the total excretion of bile acids. Significant variations were found in the concentrations of several of the bile acids both between different samples from the same subject and between samples from different subjects.

Rapid assay of poly(ADP-ribose) glycohydrolase

1987 ◽  
Vol 65 (7) ◽  
pp. 668-673 ◽  
Author(s):  
Luc Ménard ◽  
Guy G. Poirier
Keyword(s):  
Thin Layer ◽  
Enzymatic Activity ◽  
Affinity Chromatography ◽  
Thin Layer Chromatography ◽  
Rapid Method ◽  
The Other ◽  
High Yield ◽  
Rapid Assay ◽  
Layer Chromatography

We have developed a rapid, highly reproducible assay to determine poly(ADP-ribose) glycohydrolase activity which measures directly the appearance of the reaction product. We also analysed the majority of different techniques which are used to determine poly(ADP-ribose) glycohydrolase activity and found that the apparent activity can vary extensively depending on the method used. Thin-layer chromatography using PEI-F–cellulose was the only method which evaluated directly the specific release of ADP-ribose; by comparison with this method, the other procedures gave an over- or under-estimation of 2- to 10-fold of the enzymatic activity. A rapid method of affinity chromatography has also been developed to synthesize and purify in high yield poly(ADP-ribose) (35% conversion of 1 mM NAD to poly (ADP-ribose)).

scholarly journals THE SULFONATION STUDY OF REACTION MECHANISM ON PAPAVERINE ALKALOID BY GC-MS AND FT-IR

2010 ◽  
Vol 7 (1) ◽  
pp. 67-71
Author(s):  
I Made Sudarma
Keyword(s):  
Reaction Mechanism ◽  
Thin Layer ◽  
Thin Layer Chromatography ◽  
Sulfonyl Chloride ◽  
The Other ◽  
Sulfonyl Group ◽  
Molecular Ion ◽  
Ft Ir ◽  
Theoretical Mechanism ◽  
Layer Chromatography

The aim of this research was to prove theoretical mechanism reaction on the sulfonation of papaverine alkaloid and the result could be used as a reference on the transformation of these alkaloid to the other derivatives. Theoriticaly sulfonation of papaverine (1) by HO-SO2Cl could produced papaverine sulfonyl chloride (1a). The formation of this product was analyzed by analytical thin layer chromatography GC-MS, and FT-IR. These analysis showed the formation of product (1a) more favorable than the other. Tlc showed product (1a) less polar than papaverine, and supported by GC-MS and infrared which showed molecular ion at m/z 412 due to the presence of -SO2Cl and vibration at 1153,4 dan 1265,2 Cm-1 due to absorption of sulfonyl group.   Keywords: reaction mechanism, sulfonation, papaverine alkaloid.

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