scholarly journals Endo-β-mannanase Activity in Tomato and Other Ripening Fruits

HortScience ◽  
2001 ◽  
Vol 36 (1) ◽  
pp. 72-75 ◽  
Author(s):  
Richard Bourgault ◽  
J. Derek Bewley ◽  
Aurelia Alberici ◽  
Delphine Decker
Keyword(s):  
Molecular Weight ◽  
Enzyme Activity ◽  
Lycopersicon Esculentum ◽  
Protease Inhibitor ◽  
Cucumis Melo ◽  
Citrullus Lanatus ◽  
High Salt ◽  
Tomato Seed ◽  
Mannanase Activity ◽  
The Many

High amounts of endo-β-mannanase (EC 3.2.1.78) activity were extracted from tomato (Lycopersicon esculentum Mill.) fruits when a high-salt-containing buffer was used. Two pI forms of the fruit enzyme were identified, one being much more basic than the many seed isoforms. The number of isoforms increased if a protease inhibitor was not used during extraction. The enzyme was found in the ripe fruits of many other species, and was particularly active in those of muskmelon (Cucumis melo L. Cantalupensis Group) and watermelon [Citrullus lanatus (Thunb.) Matsum. and Nak.]. In most fruits, enzyme activity was localized in the skin and the epidermal and subepidermal regions. The enzyme in several fruits had a molecular weight of ≈40,000 and reacted immunologically with the tomato seed endo-β-mannanase antibody.

scholarly journals Enzyme activity in the micropylar region of Melanoxylon brauna Schott seeds during germination under heat stress conditions

2020 ◽  
Vol 42 ◽  
Author(s):  
Marcone Moreira Santos ◽  
Eduardo Euclydes de Lima e Borges ◽  
Glauciana da Mata Ataíde ◽  
Raquel Maria de Oliveira Pires ◽  
Debora Kelli Rocha
Keyword(s):  
Enzyme Activity ◽  
Heat Stress ◽  
Seed Germination ◽  
Pectin Methylesterase ◽  
Stress Conditions ◽  
Southeastern Brazil ◽  
Experimental Conditions ◽  
Mannanase Activity ◽  
Ecological Importance ◽  
The Many

Abstract: Recent studies indicate that global temperatures will rise substantially in the 21st century, leading to the extinction of several plant species, as plant metabolism and germination are greatly affected by temperature. Melanoxylon brauna, a tree species native to the Atlantic Forest that occurs from northeastern to southeastern Brazil, is one of the many species threatened by global warming. Despite the economic and ecological importance of M. brauna, studies investigating the influence of heat stress on seed germination and biochemical responses are still incipient. This study aimed to evaluate enzyme activity in the micropylar region of M. brauna seeds during germination under heat stress conditions. Endo-β-mannanase, α-galactosidase, polygalacturonase, pectin methylesterase, pectin lyase, total cellulase, 1,3-β-glucosidase, and 1,4-β-glucosidase activities were determined in micropyles of seeds imbibed for 24, 48 and 72 h at 25, 35 and 45 °C. Seed germination was highest at 25 °C. Endo-β-mannanase activity was not detected under any of the experimental conditions, but imbibition temperature had a significant effect on the activity of all other enzymes.

Biochemical Heterogeneity of Infantile Central Nervous System Spongy Degeneration

1992 ◽  
Vol 7 (1_suppl) ◽  
pp. S22-S25 ◽  
Author(s):  
Sarvepalli B. Subramanyam ◽  
Aparna Tipirneni ◽  
Nazih Youssef ◽  
Generoso G. Gascon ◽  
Pinar T. Ozand
Keyword(s):  
Molecular Weight ◽  
Central Nervous System ◽  
Nervous System ◽  
Enzyme Activity ◽  
Protease Inhibitor ◽  
Residual Activity ◽  
Normal Fibroblast ◽  
Spongy Degeneration ◽  
Two Peaks

Aspartoacylase, the enzyme whose activity is deficient in infantile central nervous system spongy degeneration (Canavan-Van Bogaert-Bertrand disease), is detected as an approximately 59-kD protein in the Sephadex G-200 filtration of normal fibroblast extracts. The enzyme activity in homogenates of fibroblasts is protected by leupeptin, a protease inhibitor. In the absence of leupeptin, 90% of aspartoacylase activity is lost. In some patients with infantile spongy degeneration, no activity (less than 2%) can be detected. In some other patients with residual activity in fibroblasts, two separate peaks of enzyme are eluted with molecular weight corresponding to approximately 59 and 19 kD. Aspartoacylase activity in this latter group is protected to the same extent by the presence of leupeptin. However, the elution of two peaks is independent of the presence of leupeptin. This study indicates biochemical heterogeneity in the pathogenesis of infantile spongy degeneration. (J Child Neurol 1992;7(Suppl):S22-S25.)

Exterior and Interior Events in Early Stage of Thrombin-induced Platelet Aggregation

1977 ◽  
Vol 38 (03) ◽  
pp. 0630-0639 ◽  
Author(s):  
Shuichi Hashimoto ◽  
Sachiko Shibata ◽  
Bonro Kobayashi
Keyword(s):  
Molecular Weight ◽  
Enzyme Activity ◽  
Plasma Membrane ◽  
Platelet Aggregation ◽  
Early Stage ◽  
Adenyl Cyclase ◽  
Cellular Component ◽  
Primary Event ◽  
Rabbit Platelets ◽  
Membrane Bound

SummaryTreatment of washed rabbit platelets with 1 u/ml of thrombin at 37° C resulted in a disappearance from platelets of a protein with 250,000 dalton molecular weight which was shown to be originated from plasma membrane. Parallel loss of adenyl cyclase was noted, and both reactions were complete within 30 sec. From the patterns of disc electrophoretograms, the importance of quick suppression of thrombin action in demonstrating the primary event was stressed.Thrombin induced an apparent activation of membrane bound phosphodiesterase. This reaction was also complete within 30 sec. The cellular component which contained the enzyme activity was distinct from plasma membrane. Soluble phosphodiesterase was not influenced by thrombin at all.These reactions required intact platelet cells to react with thrombin, and no reaction was detected when subcellular preparations were treated with thrombin.Possibility of collaboration of changes in externally located synthetic enzyme with those in internally located degrading enzyme in the early phase of thrombin action on platelets was suggested.

The Relation Between VIIIR:AG and VIII:C Studied with Two Antisera

1979 ◽  
Author(s):  
H. P. Muller ◽  
N. H. van Tilburg ◽  
R. M. Bertina ◽  
J. J. Veltkamp
Keyword(s):  
Molecular Weight ◽  
High Salt ◽  
Low Molecular Weight ◽  
Gel Chromatography ◽  
Specific Antibodies ◽  
Specific Effects ◽  
Normal Plasma ◽  
Coagulant Activity ◽  
Sterical Hindrance ◽  
Inhibitory Antibodies

FVIII was separated into low molecular weight FVIII (LMW FVIII) and high molecular weight FVIII (HMW FVIII) by gel chromatography in the presence of high salt concentration or by high salt elution of LMW FVIII from FVIII bound to anti HMW FVII-Sepharose. Specific antibodies were raised in rabbits against HMW FVIII and LMW FVIII. After removal of the contaminating anti HMW activities the rabbit anti LMW FVIII was still able to neutralize the FVIII coagulant activity of normal plasma and of IMW FVIII with canparable efficiency and it had no effect on the VIIIR:WF of FVIII in normal plasma or in HMW FVIII. Anti LMW FVIII does not bind to HMW FVIII and does not precipitate FVIII as tested by counter immunoelectrophoresis. Rabbit anti HMW FVIII precipitates FVIII in normal plasma, inhibits VIIIR:WF activity, while it has no effect on the FVIII coagulant activity of LMW FVIII. The coagulant activity of FVIII in normal plasma is slightly inhibited by anti HMW FVIII presumably by non-specific effects (sterical hindrance). It is concluded that inhibitory antibodies against VIII:C raised in rabbits recognize antigenic structures only present on LMW FVIII. Antibodies against HMW FVIII raised in rabbits appears to recognize structures only present on HMW FVIII.

scholarly journals Prototypical Recombinant Multi-Protease-Inhibitor-Resistant Infectious Molecular Clones of Human Immunodeficiency Virus Type 1

2013 ◽  
Vol 57 (9) ◽  
pp. 4290-4299 ◽  
Author(s):  
Vici Varghese ◽  
Yumi Mitsuya ◽  
W. Jeffrey Fessel ◽  
Tommy F. Liu ◽  
George L. Melikian ◽  
...  
Keyword(s):  
Amino Acid ◽  
Protease Inhibitor ◽  
Cross Resistance ◽  
Amino Acid Substitutions ◽  
Phenotypic Properties ◽  
The Public ◽  
Immunodeficiency Virus ◽  
The Many ◽  
High Level ◽  
Infectious Molecular Clones

ABSTRACTThe many genetic manifestations of HIV-1 protease inhibitor (PI) resistance present challenges to research into the mechanisms of PI resistance and the assessment of new PIs. To address these challenges, we created a panel of recombinant multi-PI-resistant infectious molecular clones designed to represent the spectrum of clinically relevant multi-PI-resistant viruses. To assess the representativeness of this panel, we examined the sequences of the panel's viruses in the context of a correlation network of PI resistance amino acid substitutions in sequences from more than 10,000 patients. The panel of recombinant infectious molecular clones comprised 29 of 41 study-defined PI resistance amino acid substitutions and 23 of the 27 tightest amino acid substitution clusters. Based on their phenotypic properties, the clones were classified into four groups with increasing cross-resistance to the PIs most commonly used for salvage therapy: lopinavir (LPV), tipranavir (TPV), and darunavir (DRV). The panel of recombinant infectious molecular clones has been made available without restriction through the NIH AIDS Research and Reference Reagent Program. The public availability of the panel makes it possible to compare the inhibitory activities of different PIs with one another. The diversity of the panel and the high-level PI resistance of its clones suggest that investigational PIs active against the clones in this panel will retain antiviral activity against most if not all clinically relevant PI-resistant viruses.

Cucurbit yellow stunting disorder virus. [Distribution map].

2016 ◽  
Author(s):  
Keyword(s):  
Saudi Arabia ◽  
North America ◽  
Central America ◽  
United Arab Emirates ◽  
Cucumis Melo ◽  
Citrullus Lanatus ◽  
Distribution Map ◽  
Virus Distribution ◽  
New Distribution ◽  
Distribution In Europe

Abstract A new distribution map is provided for Cucurbit yellow stunting disorder virus. Closteroviridae: Crinivirus. Hosts: Cucurbitaceae, especially melon (Cucumis melo), watermelon (Citrullus lanatus) and cucumber (Cucumis sativus). Information is given on the geographical distribution in Europe (Cyprus, France, Greece, Crete, Mainland Greece, Portugal, Spain, Canary Islands and Mainland Spain), Asia (China, Jiangsu, Zhejiang, Iran, Israel, Jordan, Lebanon, Saudi Arabia, Syria, Turkey and United Arab Emirates), Africa (Egypt, Morocco, Sudan and Tunisia), North America (Mexico, USA, Arizona, California, Florida and Texas) and Central America and Caribbean (Guatemala).

scholarly journals Comportamento de cultivares de meloeiro e melancia inoculados com Acremonium cucurbitacearum e Monosporascus cannonballus

2002 ◽  
Vol 27 (2) ◽  
pp. 206-210 ◽  
Author(s):  
RUI SALES JÚNIOR ◽  
ANTONIO VICENT ◽  
JOSEP ARMENGOL ◽  
JOSÉ GARCÍA-JIMÉNEZ ◽  
RÔMULO F. KOBORI
Keyword(s):  
Cucumis Melo ◽  
Citrullus Lanatus ◽  
Monosporascus Cannonballus

O colapso em cucurbitáceas é uma síndrome complexa na qual podem estar envolvidos numerosos agentes fitopatógenos, sendo bastante freqüente o ataque associado de vários deles. No presente trabalho é apresentado o comportamento de 19 cultivares de meloeiro (Cucumis melo) e duas de melancia (Citrullus lanatus), cultivadas no Brasil, frente a Acremonium cucurbitacearum e Monosporascus cannonballus, dois dos patógenos fúngicos associados a esta síndrome em diversos países. Todas as cultivares de meloiro e melancia mostraram-se susceptíveis a estes patógenos, obtendo-se valores de 2,2 até 4,4 de índice geral de doença (IGD) para as cultivares de melão inoculadas com ambos os fungos e 2,4 até 2,5 para as cultivares de melancia inoculadas com A. cucurbitacearum. As cultivares de melancia mostraram resistência na combinação com M. cannonballus. A conveniência de efetuar estudos com outras cultivares utilizando a metodologia desenvolvida neste trabalho é discutida.

Extracellular alkaline phosphatase from marine bacteria: purification and properties of extracellular phosphatase from a marine Pseudomonas sp.

1980 ◽  
Vol 26 (7) ◽  
pp. 833-838 ◽  
Author(s):  
Hiromi Kobori ◽  
Nobuo Taga
Keyword(s):  
Molecular Weight ◽  
Alkaline Phosphatase ◽  
Enzyme Activity ◽  
Marine Bacteria ◽  
Divalent Cations ◽  
Maximal Activity ◽  
Pseudomonas Sp ◽  
Purification And Properties ◽  
Extracellular Alkaline Phosphatase ◽  
Increased Pressure

Extracellular alkaline phosphatase produced by a marine Pseudomonas was purified to electrophoretic homogeneity. The molecular weight of the enzyme was estimated to be 100 000. The enzyme had maximal activity at pH 11.5. The enzyme was completely inhibited by 1 mM EDTA. However, divalent cations reversed the enzyme inhibition and their order of effectiveness on the reaction was Zn2+ > Ca2+ > Mn2+ > Mg2+ > Sr2+ > Co2+. The enzyme activity was affected by the species of anion whose order of effectiveness was demonstrated to follow the lyotrophic series, Cl− > Br− > NO3−> ClO4− > SCN−. The activity of phosphatase was accelerated linearly by increased pressure until up to 1000 atm (1 atm = 101.325 kPa), and the enzyme activity at 1000 atm was 3.2 times higher than that at 1 atm.

scholarly journals Age-related Resistance of Diverse Cucurbit Fruit to Infection by Phytophthora capsici

2009 ◽  
Vol 134 (2) ◽  
pp. 176-182 ◽  
Author(s):  
Kaori Ando ◽  
Sue Hammar ◽  
Rebecca Grumet
Keyword(s):  
Cucumis Melo ◽  
Cucurbita Pepo ◽  
Citrullus Lanatus ◽  
Phytophthora Capsici ◽  
Vegetable Production ◽  
Age Related ◽  
Cucumber Fruit ◽  
Summer Squash ◽  
Pronounced Reduction ◽  
Green Stage

Phytophthora capsici causes severe losses in vegetable production, including many cucurbit crops. Our previous work showed that cucumber (Cucumis sativus) fruit are most susceptible to P. capsici when they are very young and rapidly elongating, but develop resistance as they approach full length at 10 to 12 days postpollination (DPP). In this study, fruit from seven additional cucurbit crops representing four species, melon (Cucumis melo), butternut squash (Cucurbita moschata), watermelon (Citrullus lanatus), and zucchini, yellow summer squash, acorn squash, and pumpkin (Cucurbita pepo), were tested for the effect of fruit development on susceptibility to P. capsici. Field-grown fruit of the different crops varied in overall susceptibility. Zucchini and yellow summer squash were the most susceptible, with the majority of fruit exhibiting water-soaking symptoms within 24 hours postinoculation. Fruit from all of the crops exhibited size-related decrease in susceptibility, but to varying degrees. Cucumber had the most pronounced effect. In infested fields, cucumber fruit were found to be most frequently infected at the blossom end. Comparison of the peduncle and blossom end showed a difference in susceptibility along the length of the fruit for cucumber, butternut squash, and zucchini. Greenhouse-grown, hand-pollinated pumpkin, acorn squash, and butternut squash showed an age-related decrease in susceptibility similar to field-grown fruit. For all of these fruit, a pronounced reduction in susceptibility accompanied the transition from the waxy green to green stage at ≈3 to 8 DPP.

scholarly journals LA ROTACIÓN DE CULTIVOS Y LAS PROPIEDADES DE LA CÁSCARA DE ALMENDRA COMO SUSTRATO

2009 ◽  
Vol 32 (2) ◽  
pp. 135-142
Author(s):  
Gabino A. Martínez-Gutiérrez ◽  
Yolanda D. Ortiz-Hernández ◽  
Miguel Urrestarazu-Gavilán ◽  
Ma. del Carmen Salas-San Juán ◽  
Cirenio Escamirosa-Tinoco
Keyword(s):  
Lycopersicon Esculentum ◽  
Cucumis Melo ◽  
Prunus Dulcis ◽  
Lycopersicon Esculentum Mill ◽  
Cucumis Melo L

La cáscara del fruto del almendro (Prunus dulcis L.) es un residuo orgánico de la industria de los frutos secos, con mínima utilización en los países mediterráneos. Con el propósito de utilizar este material como medio de cultivo para hortalizas, se estudió el efecto del tiempo de uso como sustrato en función de sus propiedades físicas y químicas. Los experimentos se hicieron en invernadero tipo parral. El tiempo de uso de la cáscara de almendra como sustrato, estuvo determinado por tres ciclos de tomate (Lycopersicon esculentum Mill.) y dos de melón (Cucumis melo L.) de 165 y 100 d respectivamente, cultivados en sacos de 25 L. Para el análisis del sustrato se tomaron muestras de tres sacos de los sustratos reutilizados, por cada ciclo de cultivo. Durante los primeros 165 d de uso, el porcentaje en peso de partículas medianas (de 0.125 a 2 mm) disminuyó, mientras que las gruesas (de 4 a 8 mm) aumentaron. Hasta los 430 d de uso, tanto las partículas finas (menores a 0.125 mm) como las muy gruesas (8-16 mm) se incrementaron. A través del tiempo todas las propiedades físicas variaron significativamente. La densidad aparente disminuyó en 0.28 g cm-3, mientras que el espacio poroso total aumentó en 27 %. La mojabilidad y la contracción aumentaron más de 100 %, de acuerdo con el intervalo óptimo. Las relaciones aire-agua también se modificaron y fue a los 430 d de uso cuando la mayoría de sus valores se ubicaron en el óptimo. Los valores de las propiedades físicas y químicas fueron mejores a través del tiempo y se ubicaron en el intervalo óptimo, de modo que dicho sustrato se puede utilizar hasta 695 d. 

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