Solubilization and Selected Properties of Crambe Seed Thioglucosidase (Thioglucoside Glucohydrolase, EC 3.2.3.1)

1973 ◽  
Vol 51 (9) ◽  
pp. 1305-1310 ◽  
Author(s):  
H. L. Tookey
Keyword(s):  
Substrate Inhibition ◽  
Apparent Molecular Weight ◽  
Ferrous Ion ◽  
Soluble Enzyme ◽  
Ammonium Sulfate Precipitation ◽  
Michaelis Constant ◽  
Sequential Fractionation ◽  
Crambe Abyssinica ◽  
Crambe Seed ◽  
Insoluble Particles

Ultrasonic treatment releases thioglucoside glucohydrolase (thioglucosidase) from insoluble particles of Crambe abyssinica seed meal. The crude enzyme is optimally activated by 10−2 M ascorbate, requires a reducing agent for stability, and is inhibited by 10−3 M p-chloromercuribenzenesulfonate.Chromatography of a meal extract on cross-linked dextran separates two enzyme fractions. About 80% of the activity elutes at an apparent molecular weight of 110 000; the remainder elutes at the void volume. Both crude soluble enzyme and the fractions from the dextran column produce goitrin from epi-progoitrin, but in the presence of ferrous ion the chief aglucon product becomes 1-cyano-2-hydroxy-3-butene. The Michaelis constant (of the major peak) at pH 5 is 0.004 M. Ferrous ion produces substrate inhibition at high epi-progoitrin levels. Sequential fractionation of meal extract by ammonium sulfate precipitation and by chromatography on cross-linked dextran effects an 80-fold purification.

Effect of organic reducing agents and ferrous ion on thioglucosidase activity of Crambe abyssinica seed

1970 ◽  
Vol 48 (9) ◽  
pp. 1024-1028 ◽  
Author(s):  
H. L. Tookey ◽  
I. A. Wolff
Keyword(s):  
Reducing Agents ◽  
Ferrous Ion ◽  
Seed Meal ◽  
Crambe Abyssinica ◽  
Meal Pattern ◽  
Crambe Seed ◽  
Crambe Meal ◽  
Insoluble Particles

The addition of L-ascorbate or 2-mercaptoethanol to aged crambe seed meal tends to restore the fresh meal pattern of epi-progoitrin hydrolysis to nitriles instead of (R)-goitrin. Neither of these reducing agents has an effect on the breakdown of epi-progoitrin to goitrin by an insoluble particulate thioglucosidase from crambe meal. The addition of ferrous ion to the insoluble particles results in the conversion of epi-progoitrin to (2S)-1-cyano-2-hydroxy-3-butene instead of (R)-goitrin over a range from pH 3.9 to 6.7.

scholarly journals Relationships between thrombopoiesis and erythropoiesis: with studies of the effects of preparations of thrombopoietin and erythropoietin

Blood ◽  
1976 ◽  
Vol 48 (4) ◽  
pp. 547-558 ◽  
Author(s):  
BL Evatt ◽  
JL Spivak ◽  
J Levin
Keyword(s):  
Ammonium Sulfate ◽  
Red Cells ◽  
Red Cell ◽  
Erythropoietic Activity ◽  
Rabbit Plasma ◽  
Ammonium Sulfate Precipitation ◽  
Sequential Fractionation ◽  
Platelet Production ◽  
Cell Production

Abstract The effects of administration of partially purified human urinary erythropoietin and rabbit thrombopoietin, and of endogenously produced erythropoietin and thrombopoietin on both red cell and platelet production were examined in mice. Partially purified thrombopoietin was prepared from rabbit plasma by sequential fractionation with ammonium sulfate precipitation, and DEAE and Sephadex G-100 chromatography. Preparations of thrombopoietin and partially purified human urinary erythropoietin (NIH No. H-11-TaLSL) were administered subcutaneously to normal mice, and the rate of incorporation of selenomethionine-75 Se into platelets was measured as an index of thrombopoietic activity of the infused material. Erythropoietin and thrombopoietin were assayed for erythropoietic activity by measuring the rate of appearance of 59Fe in the red cells of posthypoxic polycythemic mice. Preparations containing thrombopoietin had barely measurable erythropoietic activity, and 7 units of partially purified erythropoietin had little thrombopoietic activity. When endogenous levels of erythropoietin were increased by hypoxia, platelet production was not enhanced. Similarly, increased levels of thrombopoietin, induced in response to thrombocytopenia produced by platelet antiserum, did not alter red cell production. These data suggest that physiologically increased levels of thrombopoietin do not stimulate erythropoiesis, and that physiologically increased levels of erythropoietn do not stimulate thrombopoiesis. However, currently available, partially purified preparations of erythropoietin and thrombopoietin may be capable of stimulating both platelet and red cell production if used in sufficient quantities.

scholarly journals THE FEEDING VALUE OF SOLVENT-EXTRACTED CAMELINA MEAL EFFECTS OF LEVELS FED, HEAT TREATMENTS AND FLAVOR SUPPLEMENTS

1967 ◽  
Vol 47 (2) ◽  
pp. 109-114 ◽  
Author(s):  
G. O. Korsrud ◽  
J. M. Bell
Keyword(s):  
Control Diet ◽  
Maximum Growth ◽  
Brassica Napus L ◽  
Growth Depression ◽  
Crambe Abyssinica ◽  
Crambe Seed ◽  
Camelina Meal ◽  
Feeding Value ◽  
Dry Heating ◽  
Camelina Seed

Camelina seed was ground, solvent-extracted, and fed at levels of 0, 5, 10, 15, 20 and 25% of the diet to weanling mice. Licorice (0 and 0.025%) was tested as a cross-treatment to modify flavor. Levels up to 10% resulted in no adverse effects on growth of mice but each increase in level beyond 10% resulted m a significant (P <.05) reduction in gains and feed intakes. Licorice was ineffective.In a second experiment 20 to 22% of camelina meal was fed m all diets. Raw meal was compared with dry-heated meal (12 hours, 135 °C), autoclaved meal (15 min, 1.2 kg/cm2), steam-stripped (2 hours, 110 °C) and a casein–methionine–supplemented control diet. In each case, four myrosinase-source supplements were added: nil, crambe seed, rapeseed, and camelina seed (Crambe abyssinica Hochst., Brassica napus L., and Cameline sativa Crantz).Destruction of myrosinase by any method of heating resulted in significantly better feeding value of camelina meal, but steam stripping was superior to dry heating or autoclaving.It was concluded that camelina meal is probably superior to rapeseed and crambe meals, in that more than 10% of raw meal is tolerated in the diet before growth depression occurs. Near maximum growth was obtained with myrosinase-free diets containing about 20% meal. Growth depression that occurred at the higher levels of intake exceeded that which could be accounted for by the content of volatile isothiocyanates.

Crambe Thioglucoside Glucohydrolase (EC 3.2.3.1): Separation of a Protein Required for Epithiobutane Formation

1973 ◽  
Vol 51 (12) ◽  
pp. 1654-1660 ◽  
Author(s):  
H. L. Tookey
Keyword(s):  
Ammonium Sulfate ◽  
Ferrous Ion ◽  
Seed Meal ◽  
Proteinaceous Material ◽  
Saturated Ammonium Sulfate ◽  
Crambe Seed

Sonicated extract of crambe seed meal prepared in the presence of ferrous ion and dithiothreitol enzymatically converts epi-progoitrin to glucose, HSO4−, and a mixture of 1-cyano-2-hydroxy-3,4-epithiobutanes (50–70%) and 1-cyano-2-hydroxy-3-butene (30–50%). A fraction of the extract precipitating between 60 and 70% saturated ammonium sulfate contains thioglucosidase that converts epi-progoitrin essentially to 1-cyano-2-hydroxy-3-butene. Chromatography (on cross-linked dextran) of a 40–60% ammonium sulfate fraction leads to separation of a proteinaceous material (s20 = 2.6 S) that does not hydrolyze epi-progoitrin but, in the presence of thioglucosidase, promotes the formation of 1-cyano-2-hydroxy-3,4-epithiobutanes in amounts proportional to those from crude seed meal extract.

2-Phosphoglycerate phosphatase and serine biosynthesis in Veillonella alcalescens

1981 ◽  
Vol 27 (8) ◽  
pp. 808-814 ◽  
Author(s):  
J. J. Pestka ◽  
E. A. Delwiche
Keyword(s):  
Biosynthetic Pathway ◽  
Gel Filtration ◽  
Deae Cellulose ◽  
Apparent Molecular Weight ◽  
Ammonium Sulfate Precipitation ◽  
Ph Optimum ◽  
Phosphoserine Aminotransferase ◽  
Cell Extracts ◽  
Phosphoglycerate Dehydrogenase ◽  
Serine Biosynthesis

The constituent enzymes for the phosphorylated and nonphosphorylated serine biosynthetic pathways in Veillonella alcalescens were identified and included phosphoserine phosphatase, 3-phosphoglycerate dehydrogenase, glycerate dehydrogenase, phosphoserine aminotransferase, and serine–pyruvate aminotransferase. Cell extracts of the organism were also found to cause the specific dephosphorylation of 2-phosphoglycerate. The phosphatase was purified 39-fold by manganese chloride precipitation, ammonium sulfate precipitation, and DEAE-cellulose chromatography. Sephadex G-200 gel filtration data established an apparent molecular weight of 50 000 for the enzyme. The 2-phosphoglycerate phosphatase had a pH optimum of 5.5 and was distinct from phosphoglyceromutase. Assays conducted with the purified enzyme on a number of other phosphorylated intermediates indicated that the phosphatase was most specific for 2-phosphoglycerate. Glucerate, hydroxypyruvate, and serine inhibited the enzyme, whereas succinate stimulated activity. Veillonella 2-phosphoglycerate phosphatase is the first such enzyme to be described in a prokaryote and is probably involved in glycerate generation for the nonphosphorylated serine biosynthetic pathway.

Inhibition Kinetics of Polyphenol Oxidase from Purple Sweet Potato by Ascorbic Acid

2013 ◽  
Vol 333-335 ◽  
pp. 1921-1925
Author(s):  
Lu Gao ◽  
Ke Da Li ◽  
Ying Chang Li
Keyword(s):  
Ascorbic Acid ◽  
Sweet Potato ◽  
Polyphenol Oxidase ◽  
Substrate Inhibition ◽  
Competitive Inhibitor ◽  
Inhibitory Effects ◽  
Michaelis Constant ◽  
Maximum Reaction ◽  
Purple Sweet Potato ◽  
Kinetics Of

With catechol as a substrate, some kinetic parameters, including Michaelis constant (Km), maximum reaction velocity (Vmax) and substrate inhibition constant (KI) for the reaction catalyzed by polyphenol oxidase (PPO) from purple sweet potato (PSP) were mainly studied here by spectrophotometry. Kmand Vmaxwere determined depending on bi-reciprocal diagram of Lineweaver-Burk and Hanes-Woolf diagram respectively, with Kmof 12.06 mM and Vmaxof 43.66 mM·min. The effects of four various inhibitors on PPO activity were different. Ascorbic acid (AA) and phytic acid (PA) showed strong inhibitory effects, with AA of the highest effect and citric acid (CA) the lowest. Among these inhibitors, AA was a reversible competitive inhibitor with KIof 15.26 mM, which was significant and instructive to the quality and benefit improvement of processed PSP products.

A Bacteriocin Produced by Lactobacillus brevis KLDS1.0373 Isolated from “Jiaoke”, a Traditional Fermented Cream from China

2011 ◽  
Vol 183-185 ◽  
pp. 1132-1136
Author(s):  
Hui Wang ◽  
Han Sheng Gong ◽  
Xiang Chen Meng ◽  
Li Li Man
Keyword(s):  
Molecular Weight ◽  
Ammonium Sulfate ◽  
Inner Mongolia ◽  
Gel Filtration ◽  
Apparent Molecular Weight ◽  
Lactobacillus Brevis ◽  
Ammonium Sulfate Precipitation ◽  
Gel Filtration Chromatography

A bacteriocin produced by Lactobacillus brevis KLDS1.0373 which was isolated from “Jiaoke”, a traditional, naturally fermented cream from Inner Mongolia in China was reported in this article. The bacteriocin was partially purified by ammonium sulfate precipitation followed by sequential gel filtration chromatography, and the apparent molecular weight of the partially purified bacteriocin was estimated at approximately 3.8 kDa.

scholarly journals Degradation of reserves of crambe seed (Crambe abyssinica) during germination

2016 ◽  
Vol 11 (11) ◽  
pp. 920-924 ◽  
Author(s):  
Fid ecirc ncio de Oliveira Elisa ◽  
Minarelli Reche Aline ◽  
Antonio Penariol da Silva Magnun ◽  
Cristina Esteves Amaro Amanda ◽  
Antonio Martin Biagionni Marco ◽  
...  
Keyword(s):  
Crambe Abyssinica ◽  
Crambe Seed

scholarly journals Relationships between thrombopoiesis and erythropoiesis: with studies of the effects of preparations of thrombopoietin and erythropoietin

Blood ◽  
1976 ◽  
Vol 48 (4) ◽  
pp. 547-558
Author(s):  
BL Evatt ◽  
JL Spivak ◽  
J Levin
Keyword(s):  
Ammonium Sulfate ◽  
Red Cells ◽  
Red Cell ◽  
Erythropoietic Activity ◽  
Rabbit Plasma ◽  
Ammonium Sulfate Precipitation ◽  
Sequential Fractionation ◽  
Platelet Production ◽  
Cell Production

The effects of administration of partially purified human urinary erythropoietin and rabbit thrombopoietin, and of endogenously produced erythropoietin and thrombopoietin on both red cell and platelet production were examined in mice. Partially purified thrombopoietin was prepared from rabbit plasma by sequential fractionation with ammonium sulfate precipitation, and DEAE and Sephadex G-100 chromatography. Preparations of thrombopoietin and partially purified human urinary erythropoietin (NIH No. H-11-TaLSL) were administered subcutaneously to normal mice, and the rate of incorporation of selenomethionine-75 Se into platelets was measured as an index of thrombopoietic activity of the infused material. Erythropoietin and thrombopoietin were assayed for erythropoietic activity by measuring the rate of appearance of 59Fe in the red cells of posthypoxic polycythemic mice. Preparations containing thrombopoietin had barely measurable erythropoietic activity, and 7 units of partially purified erythropoietin had little thrombopoietic activity. When endogenous levels of erythropoietin were increased by hypoxia, platelet production was not enhanced. Similarly, increased levels of thrombopoietin, induced in response to thrombocytopenia produced by platelet antiserum, did not alter red cell production. These data suggest that physiologically increased levels of thrombopoietin do not stimulate erythropoiesis, and that physiologically increased levels of erythropoietn do not stimulate thrombopoiesis. However, currently available, partially purified preparations of erythropoietin and thrombopoietin may be capable of stimulating both platelet and red cell production if used in sufficient quantities.

METHODOLOGY FOR DELIVERY AND KINETICS OF CLEARANCE OF INSOLUBLE PARTICLES FROM SUBLOBAR LUNG SEGMENTS

2000 ◽  
Vol 12 (1) ◽  
pp. 99-105
Author(s):  
W. M. Foster ◽  
K. MaCri ◽  
S. McCulloch ◽  
T. Myers ◽  
A. N. Freed
Keyword(s):  
Insoluble Particles ◽  
Kinetics Of
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