The Synthesis of Cellulose by an Enzyme System from a Higher Plant

1964 ◽  
Vol 86 (2) ◽  
pp. 309-310 ◽  
Author(s):  
A. D. Elbein ◽  
G. A. Barber ◽  
W. Z. Hassid
Keyword(s):  
Enzyme System ◽  
Higher Plant

OCCURRENCE AND PROPERTIES OF L-AMINOACID:2-GLYOXYLATE AMINOTRANSFERASE IN PLANTS

1965 ◽  
Vol 43 (4) ◽  
pp. 495-506 ◽  
Author(s):  
E. A. Cossins ◽  
S. K. Sinha
Keyword(s):  
Enzyme System ◽  
Intracellular Localization ◽  
Plant Tissues ◽  
Amino Group ◽  
Transaminase Activity ◽  
Higher Plant ◽  
Amino Donor ◽  
Glyoxylate Aminotransferase

Extracts prepared from a variety of higher plant tissues have been examined for L-aminoacid:2-glyoxylate aminotransferase (glyoxylate transaminase) activity. This enzyme has been detected in extracts prepared from sunflower cotyledons, corn coleoptiles, mature pea leaves, and carrot storage tissues.Measurement of glyoxylate transaminase activity was based on ability of the extracts to convert glyoxylate- 1,2-C14 to glycine-1,2-C14 in the presence of a suitable amino group donor.Properties of this enzyme system, including amino donor requirements, inhibition, pH optima, and reversibility, have been studied using extracts prepared from mature pea leaves. In sunflower cotyledons, glyoxylate transaminase activity decreased during germination. Studies of the intracellular localization of this enzyme have shown that glyoxylate transamination occurs mainly in the cytoplasm.

Electron Microscopic and Isozyme Study of a Case of Ochronosis

1972 ◽  
Vol 30 ◽  
pp. 88-89
Author(s):  
Jay W. Cha ◽  
Perry J. Melnick
Keyword(s):  
Benzene Ring ◽  
Enzyme System ◽  
Homogentisic Acid ◽  
Degenerative Changes ◽  
Acid Oxidase ◽  
Electron Microscopic ◽  
Tyrosine Metabolism ◽  
Collagenous Tissues

Hereditary ochronosis in very few cases has been examined electron microscopically or histochemically. In this disease homogentisic acid, a normal intermediary of tyrosine metabolism, forms in excessive amounts. This is believed to be due to absence or defective activity of homogentisic acid oxidase, an enzyme system necessary to break the benzene ring and to further break it down to fumaric and acetoacetic acids. Ochronotic pigment, a polymerized form of homogentisic acid, deposits mainly in mesenchymal tissues. There has been a question whether the pigment originates from the collagenous tissues, or deposits passively, where in contrast to melanin it induces degenerative changes.

Characterization of an iron-containing superoxide dismutase from a higher plant, Citrus limonum

1994 ◽  
Vol 90 (2) ◽  
pp. 339-347 ◽  
Author(s):  
Maria S. Almansa ◽  
Luis A. del Rio ◽  
Francisca Sevilla
Keyword(s):  
Superoxide Dismutase ◽  
Higher Plant ◽  
Citrus Limonum

The Kidney and Fibrinolysis

1970 ◽  
Vol 24 (01/02) ◽  
pp. 026-032 ◽  
Author(s):  
N. A Marsh
Keyword(s):  
Molecular Weight ◽  
Plasminogen Activator ◽  
Enzyme System ◽  
Normal Animal ◽  
Fibrinolytic Enzyme ◽  
The Other ◽  
Exclusion Chromatography ◽  
Normal Urine ◽  
Renal Origin ◽  
Molecular Exclusion Chromatography

SummaryMolecular exclusion chromatography was performed on samples of urine from normal and aminonucleoside nephrotic rats. Normal urine contained 2 peaks of urokinase activity, one having a molecular weight of 22,000 and the other around 200,000. Nephrotic urine contained three peaks of activity with MW’s 126,000, 60,000 and 30,000. Plasma activator determined from euglobulin precipitate had a MW. in excess of 200,000. The results indicate that in the normal animal, plasma plasminogen activator does not escape into the urine in substantial quantities but under the conditions of extreme proteinuria there may be some loss through the kidney. The alteration in urokinase output in nephrotic animals indicates a greatly disordered renal fibrinolytic enzyme system.The findings of this study largely support the hypothesis that plasma plasminogen activator of renal origin and urinary plasminogen activator (urokinase) are different molecular species.

Arterio-Venous Differences in the Components of the Fibrinolytic Enzyme System

1966 ◽  
Vol 16 (01/02) ◽  
pp. 032-037 ◽  
Author(s):  
D Ogston ◽  
C. M Ogston ◽  
N. B Bennett
Keyword(s):  
Plasminogen Activator ◽  
Enzyme System ◽  
Venous Blood ◽  
Fibrinolytic Enzyme ◽  
Blood Levels ◽  
Activator Concentration ◽  
Blood Samples ◽  
Arterial Blood ◽  
Male Subjects

Summary1. The concentration of the major components of the fibrinolytic enzyme system was compared in venous and arterial blood samples from male subjects.2. The plasminogen activator concentration was higher in venous blood and the arterio-venous difference increased as its concentration rose, but the ratio of the arterial to venous level remained constant.3. No arterio-venous difference was found for anti-urokinase activity, antiplasmin, plasminogen and fibrinogen.4. It is concluded that venous blood determinations of the components of the fibrinolytic enzyme system reflect satisfactorily arterial blood levels.

Kinetic Aspects of the Interaction of Blood Clotting Enzymes

1965 ◽  
Vol 13 (01) ◽  
pp. 155-175 ◽  
Author(s):  
H. C Hemker ◽  
P.W Hemker ◽  
E. A Loeliger
Keyword(s):  
Kinetic Analysis ◽  
Enzyme Kinetics ◽  
Blood Clotting ◽  
Enzyme System ◽  
Enzyme Kinetic ◽  
Clotting Time ◽  
Standard Methods

SummaryApplication of the methods of enzyme-kinetic analysis to the results of clotting tests is feasible and can yield useful results. However, the standard methods of enzyme kinetics are not applicable without modifications imposed by the peculiarities of the blood-clotting enzyme system. The influence of the following complicating circumstances is calculated :1. Substrate is not present in excess.2. Only relative measures exist for concentrations of substrate or enzymes.3. Enzymes and substrates are often added together.4. Reagents are not pure.5. Clotting-time is our only measure for clotting-velocity.Formulas are deduced, which makes it possible to recognize the effect of these complications.

Kinin-Forming Enzyme System in DIC

1979 ◽  
Vol 10 (1) ◽  
pp. 98-101
Author(s):  
Masahiro MAKI ◽  
Kenji SOGA
Keyword(s):  
Enzyme System

Matrix metalloproteinases in stroke

2017 ◽  
pp. 110-117
Author(s):  
А.А. Пальцын
Keyword(s):  
Matrix Metalloproteinases ◽  
Enzyme System ◽  
Enzyme Complex ◽  
Pathogenic Factors ◽  
Pathogenic Action ◽  
Activity Of Enzymes ◽  
Living Tissues ◽  
Current Reconstruction ◽  
Metalloproteinase Activity

Матриксные металлопротеиназы - ферментный комплекс, необходимый для сохранения гомеостаза. Он участник нормальной, постоянно текущей реконструкции всех живых тканей. Действие патогенных факторов нарушает слаженную работу этого комплекса. Часто нарушение выражается излишней активностью ферментов, усиливающей патогенное действие. Однако и заживление, форсированное новообразование тканевых элементов, может происходить только при повышенной, в сравнении с нормой, активности металлопротеиназ. Такая ситуация требует от медицины умения разумно вмешиваться в работу ферментной системы. В статье представлены некоторые результаты этих вмешательств. Matrix metalloproteinases - enzyme complex necessary for maintenance of the homeostasis. He is a participant of normal, constantly current reconstruction of all living tissues. Action of pathogenic factors breaks harmonious work of this complex. Often violation is expressed by the excessive activity of enzymes amplifying pathogenic action. However and healing, which is accelerated new growth of tissue elements, can happen only at raised, compared with norm, metalloproteinase activity. Such situation demands from medicine of ability participate reasonably in work of enzyme system. The article presents some of the results of these actions.

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