HYDROLYSIS OF SOME DEOXYRIBONUCLEOSIDES BY WHEAT LEAF JUICE

1961 ◽  
Vol 39 (9) ◽  
pp. 1333-1334
Author(s):  
D. W. A. Roberts
Keyword(s):  
Wheat Leaf ◽  
Hydrolysis Of ◽  
Leaf Juice

Enzymes present in wheat leaf juice convert deoxyadenosine into adenine and deoxyribose, deoxycytidine into deoxyuridine, and 5-methyldeoxycytidine into thymidine.

THE WHEAT LEAF PHOSPHATASES: VI. SOME PROPERTIES OF THE ENZYME SYSTEM HYDROLYZING ADENOSINE-5′-PHOSPHATE AND PHENOLPHTHALEIN DIPHOSPHATE IN CRUDE JUICE PREPARATIONS

1963 ◽  
Vol 41 (5) ◽  
pp. 1275-1281 ◽  
Author(s):  
D. W. A. Roberts
Keyword(s):  
Enzyme System ◽  
The Other ◽  
Enzymic Hydrolysis ◽  
Ph Optimum ◽  
Wheat Leaf ◽  
Hydrolysis Of ◽  
Leaf Juice

At least two enzymes are probably involved in the hydrolysis of mixtures of β-glycerophosphate, phenolphthalein diphosphate, and adenosine-5′-phosphate. One enzyme is primarily responsible for the hydrolysis of β-glycerophosphate whereas the other enzyme hydrolyzes adenosine-5′-phosphate and phenolphthalein diphosphate but has little activity on β-glycerophosphate.The liberation of orthophosphate from adenosine-5′-phosphate and phenolphthalein diphosphate by the enzyme in wheat leaf juice is inhibited by 0.005 M adenosine but not by 0.02 M phosphate. The inhibition of this enzyme by fluoride is markedly smaller than the inhibition of β-glycerophosphatase. The enzyme that hydrolyzes phenolphthalein diphosphate transfers phosphate from phenolphthalein diphosphate to adenosine to form adenosine-5′-phosphate.Experiments on the pH optimum for the enzymic hydrolysis of both adenosine-5′-phosphate and phenolphthalein diphosphate by undialyzed and dialyzed juice preparations with or without added Mg++ suggest that there may be more than one enzyme with different pH optima acting on both adenosine-5′-phosphate and phenolphthalein diphosphate.

THE WHEAT LEAF PHOSPHATASES: VI. SOME PROPERTIES OF THE ENZYME SYSTEM HYDROLYZING ADENOSINE-5′-PHOSPHATE AND PHENOLPHTHALEIN DIPHOSPHATE IN CRUDE JUICE PREPARATIONS

1963 ◽  
Vol 41 (1) ◽  
pp. 1275-1281 ◽  
Author(s):  
D. W. A. Roberts
Keyword(s):  
Enzyme System ◽  
The Other ◽  
Enzymic Hydrolysis ◽  
Ph Optimum ◽  
Wheat Leaf ◽  
Hydrolysis Of ◽  
Leaf Juice

At least two enzymes are probably involved in the hydrolysis of mixtures of β-glycerophosphate, phenolphthalein diphosphate, and adenosine-5′-phosphate. One enzyme is primarily responsible for the hydrolysis of β-glycerophosphate whereas the other enzyme hydrolyzes adenosine-5′-phosphate and phenolphthalein diphosphate but has little activity on β-glycerophosphate.The liberation of orthophosphate from adenosine-5′-phosphate and phenolphthalein diphosphate by the enzyme in wheat leaf juice is inhibited by 0.005 M adenosine but not by 0.02 M phosphate. The inhibition of this enzyme by fluoride is markedly smaller than the inhibition of β-glycerophosphatase. The enzyme that hydrolyzes phenolphthalein diphosphate transfers phosphate from phenolphthalein diphosphate to adenosine to form adenosine-5′-phosphate.Experiments on the pH optimum for the enzymic hydrolysis of both adenosine-5′-phosphate and phenolphthalein diphosphate by undialyzed and dialyzed juice preparations with or without added Mg++ suggest that there may be more than one enzyme with different pH optima acting on both adenosine-5′-phosphate and phenolphthalein diphosphate.

scholarly journals Hydrolysis of Agave fourcroydes Lemaire (henequen) leaf juice and fermentation with Kluyveromyces marxianus for ethanol production

2014 ◽  
Vol 14 (1) ◽  
pp. 14 ◽  
Author(s):  
Pablo A Villegas-Silva ◽  
Tanit Toledano-Thompson ◽  
Blondy B Canto-Canché ◽  
Alfonso Larqué-Saavedra ◽  
Luis F Barahona-Pérez
Keyword(s):  
Ethanol Production ◽  
Kluyveromyces Marxianus ◽  
Agave Fourcroydes ◽  
Hydrolysis Of ◽  
Leaf Juice

PHYSIOLOGICAL AND BIOCHEMICAL STUDIES IN PLANT METABOLISM: VIII. THE DISTRIBUTION OF INVERTASE IN THE FIRST LEAF OF KHAPLI WHEAT

1953 ◽  
Vol 31 (4) ◽  
pp. 367-382 ◽  
Author(s):  
D. W. A. Roberts
Keyword(s):  
Maximum Concentration ◽  
Vascular Tissue ◽  
Quantitative Estimation ◽  
Plant Metabolism ◽  
Phloem Parenchyma ◽  
Biochemical Studies ◽  
Wheat Leaf ◽  
Kinetics Of ◽  
Physiological And Biochemical ◽  
Leaf Juice

The kinetics of wheat leaf invertase have been investigated as a basis for its quantitative estimation. No evidence was obtained which indicated that wheat leaf invertase consists of a phosphorylase and a phosphatase. Solid preparations of the enzyme may be made by precipitating the invertase with ammonium sulphate from wheat leaf juice which has been previously freed from chlorophyll by precipitation with acetate buffer at pH 4.5. A study of the distribution of this enzyme in the first leaf of wheat shows that the enzyme reaches its maximum concentration in the leaf just at the close of the period of elongation. The enzyme is more abundant in the basal part of the leaf than the tip and this condition is taken to indicate that the enzyme is associated with the vascular tissue (phloem or phloem parenchyma) rather than the chlorenchyma.

THE WHEAT LEAF PHOSPHATASES: VII. FURTHER STUDIES ON INHIBITORS AT pH 5.7

1963 ◽  
Vol 41 (1) ◽  
pp. 1727-1731 ◽  
Author(s):  
D. W. A. Roberts
Keyword(s):  
Acid Phosphatase ◽  
Enzymatic Hydrolysis ◽  
Inhibitory Effect ◽  
Substrate Specificities ◽  
Nitrophenyl Phosphate ◽  
Wheat Leaf ◽  
Hydrolysis Of

A survey of the inhibitory effect of various ribonucleosides, deoxyribonucleosides, sugars, phenols, and vitamins on the hydrolysis of 17 phosphatase substrates has been made. The more soluble ribonucleosides and deoxyribonucleosides inhibited the enzymatic hydrolysis of adenosine 5′-phosphate, phenolphthalein diphosphate, phenylphosphate, p-nitrophenyl phosphate, and in some cases the hydrolysis of adenosine 3′-phosphate, adenosine 2′-phosphate, and riboflavin 5′-phosphate. A 0.02 M concentration of orthophosphate inhibited the hydrolysis of all the compounds tested except adenosine 5′-phosphate and phenolphthalein diphosphate.These results, together with earlier findings, are discussed in terms of the concept that wheat leaf press juice contains two types of acid phosphatase, namely, β-glycerophosphatase and adenosine 5′-phosphatase. These two types of enzyme appear to have partially overlapping substrate specificities.

CATALASE ACTIVITY OF WHEAT LEAF JUICE IN RELATION TO FROST RESISTANCE

1931 ◽  
Vol 5 (3) ◽  
pp. 333-336 ◽  
Author(s):  
R. Newton ◽  
W. R. Brown
Keyword(s):  
Winter Wheat ◽  
Catalase Activity ◽  
Frost Resistance ◽  
Late Summer ◽  
Winter Hardiness ◽  
Wheat Leaf ◽  
Wheat Leaves ◽  
Leaf Juice

The catalase activity of press-juice of winter wheat leaves collected from the field at any time during the late summer and fall was directly related to the winter hardiness of varieties.

THE WHEAT LEAF PHOSPHATASES: VII. FURTHER STUDIES ON INHIBITORS AT pH 5.7

1963 ◽  
Vol 41 (8) ◽  
pp. 1727-1731 ◽  
Author(s):  
D. W. A. Roberts
Keyword(s):  
Acid Phosphatase ◽  
Enzymatic Hydrolysis ◽  
Inhibitory Effect ◽  
Substrate Specificities ◽  
Nitrophenyl Phosphate ◽  
Wheat Leaf ◽  
Hydrolysis Of

A survey of the inhibitory effect of various ribonucleosides, deoxyribonucleosides, sugars, phenols, and vitamins on the hydrolysis of 17 phosphatase substrates has been made. The more soluble ribonucleosides and deoxyribonucleosides inhibited the enzymatic hydrolysis of adenosine 5′-phosphate, phenolphthalein diphosphate, phenylphosphate, p-nitrophenyl phosphate, and in some cases the hydrolysis of adenosine 3′-phosphate, adenosine 2′-phosphate, and riboflavin 5′-phosphate. A 0.02 M concentration of orthophosphate inhibited the hydrolysis of all the compounds tested except adenosine 5′-phosphate and phenolphthalein diphosphate.These results, together with earlier findings, are discussed in terms of the concept that wheat leaf press juice contains two types of acid phosphatase, namely, β-glycerophosphatase and adenosine 5′-phosphatase. These two types of enzyme appear to have partially overlapping substrate specificities.

NUTRITION OF THE PALE WESTERN CUTWORM, AGROTIS ORTHOGONIA MORR. (LEPIDOPTERA: NOCTUIDAE): I. EFFECTS OF UNDERFEEDING AND ARTIFICIAL DIETS ON GROWTH AND DEVELOPMENT, AND A COMPARISON OF WHEAT SPROUTS OF THATCHER, TRITICUM AESTIVUM L., AND GOLDEN BALL, T. DURUM DESF., AS FOOD

1959 ◽  
Vol 37 (3) ◽  
pp. 259-266 ◽  
Author(s):  
A. J. McGinnis ◽  
R. Kasting
Keyword(s):  
Dry Matter ◽  
Growth Curves ◽  
Triticum Aestivum L ◽  
Rapid Rise ◽  
Artificial Diets ◽  
Wheat Leaf ◽  
Golden Ball ◽  
Ad Libitum ◽  
Lepidoptera Noctuidae ◽  
Leaf Juice

Larvae of the pale western cutworm fed ad libitum on Thatcher wheat sprouts required six instars to mature and increased in weight from 0.25 mg to near 700 mg in about 4 weeks. Larvae fed for only 2 hours each day required an additional instar, developed more slowly, and were smaller. The growth curves were generally similar as both exhibited a plateau before each molt, followed by a rapid rise. Of four artificial diets tested, only the two containing wheat-leaf juice permitted weight increases. The percentages of dry matter and nitrogen in the cutworm varied according to the stage of larval development and the variety of wheat sprouts fed. These factors, as well as underfeeding, also influenced the efficiency with which the cutworm converted its food to body tissue.

Fine Structural Localization of Acyltransferases Involved in Lipid Synthesis in Intestinal Mucosa.

1970 ◽  
Vol 28 ◽  
pp. 54-55
Author(s):  
R. J. Barrnett ◽  
J. A. Higgins
Keyword(s):  
Smooth Endoplasmic Reticulum ◽  
Lipid Synthesis ◽  
Mucosal Cell ◽  
Structural Localization ◽  
Morphological Studies ◽  
Mucosal Cells ◽  
Initial Appearance ◽  
Sh Group ◽  
Hydrolysis Of ◽  
Intestinal Mucosal Cells

The main products of intestinal hydrolysis of dietary triglycerides are free fatty acids and monoglycerides. These form micelles from which the lipids are absorbed across the mucosal cell brush border. Biochemical studies have indicated that intestinal mucosal cells possess a triglyceride synthesising system, which uses monoglyceride directly as an acylacceptor as well as the system found in other tissues in which alphaglycerophosphate is the acylacceptor. The former pathway is used preferentially for the resynthesis of triglyceride from absorbed lipid, while the latter is used mainly for phospholipid synthesis. Both lipids are incorporated into chylomicrons. Morphological studies have shown that during fat absorption there is an initial appearance of fat droplets within the cisternae of the smooth endoplasmic reticulum and that these subsequently accumulate in the golgi elements from which they are released at the lateral borders of the cell as chylomicrons.We have recently developed several methods for the fine structural localization of acyltransferases dependent on the precipitation, in an electron dense form, of CoA released during the transfer of the acyl group to an acceptor, and have now applied these methods to a study of the fine structural localization of the enzymes involved in chylomicron lipid biosynthesis. These methods are based on the reduction of ferricyanide ions by the free SH group of CoA.

Lattice imaging and pore structure of β ferric oxyhydroxide

1978 ◽  
Vol 36 (1) ◽  
pp. 264-265
Author(s):  
T. Baird ◽  
J.R. Fryer ◽  
S.T. Galbraith
Keyword(s):  
Electron Microscopy ◽  
Room Temperature ◽  
Bulk Material ◽  
Model Structure ◽  
Bulk Crystals ◽  
Lattice Imaging ◽  
Thin Sections ◽  
Ferric Oxyhydroxide ◽  
Resolution Electron ◽  
Hydrolysis Of

Introduction Previously we had suggested (l) that the striations observed in the pod shaped crystals of β FeOOH were an artefact of imaging in the electron microscope. Contrary to this adsorption measurements on bulk material had indicated the presence of some porosity and Gallagher (2) had proposed a model structure - based on the hollandite structure - showing the hollandite rods forming the sides of 30Å pores running the length of the crystal. Low resolution electron microscopy by Watson (3) on sectioned crystals embedded in methylmethacrylate had tended to support the existence of such pores.We have applied modern high resolution techniques to the bulk crystals and thin sections of them without confirming these earlier postulatesExperimental β FeOOH was prepared by room temperature hydrolysis of 0.01M solutions of FeCl3.6H2O, The precipitate was washed, dried in air, and embedded in Scandiplast resin. The sections were out on an LKB III Ultramicrotome to a thickness of about 500Å.

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