scholarly journals Purification and Characterization of Cellobiose Dehydrogenase from the Plant Pathogen Sclerotium(Athelia) rolfsii

2001 ◽  
Vol 67 (4) ◽  
pp. 1766-1774 ◽  
Author(s):  
Ursula Baminger ◽  
Sai S. Subramaniam ◽  
V. Renganathan ◽  
Dietmar Haltrich
Keyword(s):  
Sclerotium Rolfsii ◽  
Cation Radical ◽  
Molecular Size ◽  
Extracellular Enzyme ◽  
Cellobiose Dehydrogenase ◽  
Phytopathogenic Fungus ◽  
Athelia Rolfsii ◽  
Heme Domain ◽  
Acid Cation

ABSTRACT Cellobiose dehydrogenase (CDH) is an extracellular hemoflavoenzyme produced by several wood-degrading fungi. In the presence of a suitable electron acceptor, e.g., 2,6-dichloro-indophenol (DCIP), cytochromec, or metal ions, CDH oxidizes cellobiose to cellobionolactone. The phytopathogenic fungus Sclerotium rolfsii (teleomorph: Athelia rolfsii) strain CBS 191.62 produces remarkably high levels of CDH activity when grown on a cellulose-containing medium. Of the 7,500 U of extracellular enzyme activity formed per liter, less than 10% can be attributed to the proteolytic product cellobiose:quinone oxidoreductase. As with CDH from wood-rotting fungi, the intact, monomeric enzyme from S. rolfsii contains one heme b and one flavin adenine dinucleotide cofactor per molecule. It has a molecular size of 101 kDa, of which 15% is glycosylation, and a pI value of 4.2. The preferred substrates are cellobiose and cellooligosaccharides; additionally, β-lactose, thiocellobiose, and xylobiose are efficiently oxidized. Cytochrome c (equine) and the azino-di-(3-ethyl-benzthiazolin-6-sulfonic acid) cation radical were the best electron acceptors, while DCIP, 1,4-benzoquinone, phenothiazine dyes such as methylene blue, phenoxazine dyes such as Meldola's blue, and ferricyanide were also excellent acceptors. In addition, electrons can be transferred to oxygen. Limited in vitro proteolysis with papain resulted in the formation of several protein fragments that are active with DCIP but not with cytochrome c. Such a flavin-containing fragment, with a mass of 75 kDa and a pI of 5.1 and lacking the heme domain, was isolated and partially characterized.

scholarly journals Chemical Profile, In Vitro Biological Activity and Comparison of Essential Oils from Fresh and Dried Flowers of Lavandula angustifolia L.

Molecules ◽  
2021 ◽  
Vol 26 (17) ◽  
pp. 5317
Author(s):  
Claudio Caprari ◽  
Francesca Fantasma ◽  
Fabio Divino ◽  
Antonio Bucci ◽  
Maria Iorizzi ◽  
...  
Keyword(s):  
Antioxidant Activity ◽  
Essential Oils ◽  
Fruits And Vegetables ◽  
Central Italy ◽  
Radical Scavenging ◽  
Sclerotium Rolfsii ◽  
Bactericidal Effect ◽  
Phytopathogenic Fungus ◽  
Lavandula Angustifolia

The chemical composition of essential oils (EOs) from dried and fresh flowers of Lavandula angustifolia L. (lavender), named LA 2019 and LA 2020, respectively, grown in central Italy was analyzed and compared by GC and GC-MS. For both samples, 61 compounds were identified, corresponding to 97.9% and 98.1% of the total essential oils. Explorative data analysis, performed to compare the statistical composition of the samples, resulted in a high level of global similarity (around 93%). The compositions of both samples were characterized by 10 major compounds, with a predominance of Linalool (35.3–36.0%), Borneol (15.6–19.4%) and 1,8-Cineole (11.0–9.0%). The in vitro antibacterial activity assay by disk diffusion tests against Bacillus subtilis PY79 and Escherichia coli DH5α showed inhibition of growth in both indicator strains. In addition, plate counts revealed a bactericidal effect on E. coli, which was particularly noticeable when using oil from the fresh lavender flowers at the highest concentrations. An in vitro antifungal assay showed that the EOs inhibited the growth of Sclerotium rolfsii, a phytopathogenic fungus that causes post-harvest diseases in many fruits and vegetables. The antioxidant activity was also assessed using the ABTS free radical scavenging assay, which showed a different antioxidant activity in both EOs. In addition, the potential application of EOs as a green method to control biodeterioration phenomena on an artistic wood painting (XIX century) was evaluated.

scholarly journals Characterization of a cellobiose dehydrogenase in the cellulolytic fungus Sporotrichum (Chrysosporium) thermophile

1982 ◽  
Vol 203 (1) ◽  
pp. 277-284 ◽  
Author(s):  
M R Coudray ◽  
G Canevascini ◽  
H Meier
Keyword(s):  
Methylene Blue ◽  
Extracellular Enzyme ◽  
Electron Acceptors ◽  
Cellobiose Dehydrogenase ◽  
Ph Optimum ◽  
Phenazine Methosulphate ◽  
Reduced Activity ◽  
Cellobionic Acid

An extracellular enzyme from culture filtrates of Sporotrichum (Chrysosporium) thermophile (A.T.C.C. 42 464) after growth on cellulose or cellobiose was shown to oxidize cellobiose to cellobionic acid in vitro. Lactose and cellodextrins were also efficiently oxidized, but the enzyme was not active against most mono- and di-saccharides. Several redox substances could act as electron acceptors, but molecular oxygen, tetrazolium salts and NAD(P) were not reduced. Activity was stimulated up to 2-fold in the presence of 0.05 M-Mg2+. The pH optimum of the enzymic reaction was acidic when the activity was tested with dichlorophenol-indophenol or Methylene Blue, but was neutral to alkaline for 3,5-di-t-butyl-1,2-benzoquinone or phenazine methosulphate as electron acceptors. As the enzyme was formed inductively in parallel with the endocellulase, its possible function in relation to cellulolysis is discussed.

Antifungal activity of ethanolic and petroleum ether extracts of some medicinal plants against the plant pathogenic fungus Sclerotium rolfsii sacc.

2016 ◽  
Vol 5 (07) ◽  
pp. 4714
Author(s):  
Smrity Prabha ◽  
Bapat U. C.* ◽  
Jyoti Kumar
Keyword(s):  
Medicinal Plants ◽  
Petroleum Ether ◽  
Pathogenic Fungus ◽  
Petroleum Ether Extract ◽  
Sclerotium Rolfsii ◽  
Phytopathogenic Fungus ◽  
Acorus Calamus ◽  
Lawsonia Inermis ◽  
Justicia Adhatoda

The anti-fungal activity of ethanolic and petroleum ether extracts of eight medicinal plants, viz., Acorus calamus Linn, Justicia adhatoda L. Lawsonia Inermis L., Lantana camara Linn., Pongamia pinnata (L.) Pierre, Solanum nigrum Linn., Vitex negundo L. and Wedelia chinensis (Osbeck) Merr. were tested in vitro against phytopathogenic fungus Sclerotium rolfsii Sacc.was evaluated using poison food method. The results obtained showed that the Petroleum ether extracts of leaves and flowers of L.camara, leaves of Lawsonia inermis and S.nigrum did not inhibit the growth of S. rolfsii. However, it was observed that the ethanolic extracts of the rhizome of A. calamus and the leaves of L. Camara showed 61% and 50% inhibition of the growth of S. Rolfsii respectively. The most promising results were obtained with the petroleum ether extract of A. calamus, which exhibited 100% inhibition of S. Rolfsii with MIC of 10.4 mg/ ml. 

Management of collar rot disease in chickpea by Trichoderma species

2020 ◽  
Vol 7 (03) ◽  
Author(s):  
PREM PANDEY ◽  
G. C. SAGAR ◽  
SUNDARMAN SHRESTHA2 ◽  
HIRAKAJI MANANDHAR ◽  
RITESH K. YADAV ◽  
...  
Keyword(s):  
Growth Inhibition ◽  
Mycelial Growth ◽  
Sclerotium Rolfsii ◽  
Maximum Growth ◽  
Pot Experiment ◽  
Trichoderma Spp ◽  
Trichoderma Species ◽  
Collar Rot ◽  
Rot Disease

Nine isolates of Trichoderma spp. were isolated from different agro- ecological regions of Nepal viz; Jumla, Palpa, Chitwan, Tarahara, Banke, Illam and Salyan and screened against Sclerotium rolfsii Sacc. Adreded soil borne phytopathogen causing collar rot of chickpea in chickpea; In-vitro efficacy of nine fungal antagonist (Trichoderma spp.) against Sclerotium rolfsii were screened. Pot experiment was done to find out the effective management of S. rolfsi through Tricoderma using different methods i.e. Seed treatment, soil drenching and soil application. All the tested isolates of Trichoderma spp. were found effective on mycelial growth inhibition and sclerotial parasitization of S. rolfsii. Trichoderma isolated from Palpa district showed maximum growth inhibition (%) of pathogen periodically after 48(93.78%), 72(96.00%), 96(97.96%) and 120(100.00%) hours of inoculation. Parasitized sclerotium showed minimum sclerotial germination on agar plates. Moreover, Trichoderma species isolated from Palpa districts showed second best percent mycelial growth inhibition periodically at 72(25.00%), 120(29.16%), 168(29.16%) and 216(29.16%).In pot experiment at 40 days after sowing, Seedling height was maximum in soil drenching with 30g per 100ml of water (22.27cm) and Mortality percentage of seedlings was least or highest disease control was observed in seed treated with 109cfu/ml (0.000%).

scholarly journals In vitro conversion of proapoprotein A-I to apoprotein A-I. Partial characterization of an extracellular enzyme activity.

1983 ◽  
Vol 258 (19) ◽  
pp. 11430-11433 ◽  
Author(s):  
C Edelstein ◽  
J I Gordon ◽  
K Toscas ◽  
H F Sims ◽  
A W Strauss ◽  
...  
Keyword(s):  
Enzyme Activity ◽  
Extracellular Enzyme ◽  
Extracellular Enzyme Activity ◽  
Partial Characterization

scholarly journals Enzymic characterization in vitro of recombinant proprotein convertase PC4

1999 ◽  
Vol 343 (1) ◽  
pp. 29-37 ◽  
Author(s):  
Ajoy BASAK ◽  
Bakary B. TOURÉ ◽  
Claude LAZURE ◽  
Majambu MBIKAY ◽  
Michel CHRÉTIEN ◽  
...  
Keyword(s):  
Synthetic Peptides ◽  
Serine Proteases ◽  
Active Form ◽  
Molecular Size ◽  
Maximal Activity ◽  
Transition Metal Ions ◽  
Proprotein Convertase ◽  
Major Band ◽  
Insulin Growth Factor

Proprotein convertase PC4A, a member of the subtilisin/kexin family of serine proteases, was obtained in enzymically active form following expression of vaccinia virus recombinant rat (r)PC4A in GH4C1 cells. It displayed maximal activity at pH 7.0 and a Ca2+ concentration of 2.0 mM. Using PC4-specific antibodies, Western blot analysis of the medium revealed a major band at ≈ 54 kDa, corresponding to the molecular size of mature rPC4A. Among the various peptidyl-[4-methylcoumarin 7-amide (MCA)] substrates tested, the one that was preferred the most by rPC4A was acetyl (Ac)-Arg-Lys-Lys-Arg-MCA, which is cleaved 9 times faster (as judged from Vmax/Km measurements) than the best furin and PC1 substrate, pGlu-Arg-Thr-Lys-Arg-MCA. Recombinant rPC4A, along with human (h)furin and hPC1, cleaved a 17-amino-acid synthetic peptide, YQTLRRRVKR↓ SLVVPTD (where ↓ denotes site of cleavage, and the important basic residues are shown in bold), encompassing the junction between the putative pro-segment of rPC4A and the active enzyme, suggesting a possible auto-activation of the enzyme. In an effort to identify potential physiological substrates for PC4, studies were performed with pro-[insulin-growth-factor (IGF)]-derived synthetic peptides, namely Ac-PAKSAR↓ SVRA (IGF-I66-75) and Ac-PAKSER↓ DVST (IGF-II63-72), as well as two lysine mutants [(IGF-I66-75Lys70) and (IGF-II63-72Lys67)]. Unlike PC1 and furin, rPC4A cleaved efficiently both IGF-I66-75 and IGF-II63-72, suggesting a possible role of PC4 in the maturation of IGF-I and -II. In contrast, the peptides with a position 2 (P2) lysine mutation, IGF-I66-75Lys70 and IGF-II63-72Lys67, were cleaved more efficiently by PC1 and furin compared with rPC4A. Furthermore, using synthetic peptides containing the processing sites of pituitary adenylate-cyclase-activating polypeptide (PACAP)-38, we were able to confirm that, of the two testicular enzymes PC4 and PC7, PC4 is the best candidate enzyme for maturation of PACAP. Our data suggest that rPC4A is a functionally active convertase, with a substrate specificity somewhat different from that of other convertases, namely KXXR↓ (where X denotes any other residue). As expected, p-chloromercuribenzoic acid and metal chelators such as EDTA, EGTA and trans-1,2-diaminocyclohexane-N,N,N′,N′-tetraacetic acid inhibit the proteolytic activity of rPC4A, whereas it is activated by dithiothreitol. PC4A was also inhibited by transition-metal ions (Cu2+>Hg2+>Zn2+ Ni2+>Co2+), as well as by small peptide semicarbazones (SCs), such as Arg-Lys-Lys-Arg-SC (Ki 0.75 μM) and Arg-Ser-Lys-Arg-SC (Ki 11.4 μM).

Ficoll and dextran vs. globular proteins as probes for testing glomerular permselectivity: effects of molecular size, shape, charge, and deformability

2005 ◽  
Vol 288 (4) ◽  
pp. F605-F613 ◽  
Author(s):  
Daniele Venturoli ◽  
Bengt Rippe
Keyword(s):  
Hard Spheres ◽  
Molecular Size ◽  
Globular Proteins ◽  
Molecular Probes ◽  
Glomerular Permeability ◽  
Ample Evidence ◽  
Deformable Structure ◽  
Glomerular Barrier ◽  
Size Asymmetry

Polydisperse mixtures of dextran or Ficoll have been frequently used as molecular probes for studies of glomerular permselectivity because they are largely inert and not processed (reabsorbed) by the proximal tubules. However, dextrans are linear, flexible molecules, which apparently are hyperpermeable across the glomerular barrier. By contrast, the Ficoll molecule is almost spherical. Still, there is ample evidence that Ficoll fractional clearances (sieving coefficients) across the glomerular capillary wall (GCW) are markedly higher than those for neutral globular proteins of an equivalent in vitro Stokes-Einstein (SE) radius. Physical data, obtained by “crowding” experiments or measurements of intrinsic viscosity, suggest that the Ficoll molecule exhibits a rather open, deformable structure and thus deviates from an ideally hard sphere. This is also indicated from the relationship between (log) in vitro SE radius and (log) molecular weight (MW). Whereas globular proteins seem to behave in a way similar to hydrated hard spheres, polydisperse dextran and Ficoll exhibit in vitro SE radii that are much larger than those for compact spherical molecules of equivalent MW. For dextran, this can be partially explained by a high-molecular-size asymmetry. However, for Ficoll the explanation may be that the Ficoll molecule is more flexible (deformable) than are globular proteins. An increased compressibility of Ficoll and an increased deformability and size asymmetry for dextran may be the explanation for the fact that the permeability of the GCW is significantly higher when assessed using polysaccharides such as Ficoll or dextran compared with that obtained using globular proteins as molecular size probes. We suggest that molecular deformability, besides molecular size, shape, and charge, plays a crucial role in determining the glomerular permeability to molecules of different species.

scholarly journals A macromolecular inhibitor of the antizyme to ornithine decarboxylase

1982 ◽  
Vol 204 (3) ◽  
pp. 647-652 ◽  
Author(s):  
K Fujita ◽  
Y Murakami ◽  
S Hayashi
Keyword(s):  
Ornithine Decarboxylase ◽  
Rat Liver ◽  
Molecular Size ◽  
Antizyme Inhibitor ◽  
Heat Labile

A macromolecular factor that inhibits the activity of the antizyme to ornithine decarboxylase (ODC) was found in rat liver extracts. The factor, ‘antizyme inhibitor’, was heat-labile, non diffusable and of similar molecular size to ODC. The antizyme inhibitor re-activated ODC that had been inactivated by antizyme, apparently by replacing ODC in a complex with antizyme. Therefore the antizyme inhibitor can be used to assay the amount of inactive ODC-antizyme complex formed in vitro. When assayed by this method, the complex was shown to be eluted before ODC from a Sephadex G-100 column. Significant increase in ODC activity was observed when the antizyme inhibitor was added to crude liver extracts from rats that had been injected with 1,3-diaminopropane to cause decay of ODC activity, suggesting the presence of inactive ODC-antizyme complex in the extracts.

Endophytic Bacteria of Cotton and Sweet Corn for Providing Growth Promotion and Biological Disease Control

1996 ◽  
Author(s):  
Joseph W. Kloepper ◽  
Ilan Chet
Keyword(s):  
Seed Treatment ◽  
Protein Production ◽  
Sweet Corn ◽  
Growth Promotion ◽  
Sclerotium Rolfsii ◽  
Chitinolytic Enzymes ◽  
Low Concentrations ◽  
Bacillus Spp ◽  
Biological Control Potential

Endophytes were isolated from 16.7% of surface-disinfested seeds and 100% of stems and roots of field-growth plants. Strains from Israel with broad-spectrum in vitro antibiosis were mainly Bacillus spp., and some were chitinolytic. Following dipping of cut cotton roots into suspensions of these strains, endophytes were detected up to 72 days later by isolation and by autoradiograms of 14C-labelled bacteria. Selected endophytes exhibited biological control potential based on significant reductions in disease severity on cotton inoculated with Rhizoctonia solani or Fusarium oxysporum f. sp. vasinfectum as well as control of Sclerotium rolfsii on bean. Neither salicylic acid nor chitinase levels increased in plants as a result of endophytic colonization, suggesting that the observed biocontrol was not accounted for by PR protein production. Some biocontrol endophytes secreted chitinolytic enzymes. Model endophytic strains inoculated into cotton stems via stem injection showed only limited movement within the stem. When introduced into stems at low concentrations, endophytes increased in population density at the injection site. After examining several experimental and semi-practical inoculation systems, seed treatment was selected as an efficient way to reintroduce most endophytes into plants.

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