scholarly journals Studies on the effect of fungicides incorporated into the culture medium on fungi damaging ancient paper

2014 ◽  
Vol 11 (1) ◽  
pp. 3-16
Author(s):  
A. Strzelczyk
Keyword(s):  
Enzyme Activity ◽  
Spore Germination ◽  
Culture Medium ◽  
Cellulolytic Enzymes ◽  
Phenolic Derivatives

The aim of this work was to study the effect of fungicides contained in the medium on spore germination, on growth of colonies and on biosynthesis of cellulolytic enzymes of fungi isolated from damaged ancient books. Influence of various temperatures on the biosynthesis of cellulases was also studied. It was shown that mercuric fungicides were more effective in inhibition of spore germination and cellulytic enzyme activity than phenolic derivatives. The biosynthesis of cellulases was more effective in 16-18º than in 23 and 30ºC. The phenomenon of adaptation to small amounts of fungicides was observed.

scholarly journals Partial purification and characterization of an endo-α-N-acetylgalactosaminidase from the culture medium of Streptomyces sp. OH-11242

1992 ◽  
Vol 288 (2) ◽  
pp. 475-482 ◽  
Author(s):  
I Ishii-Karakasa ◽  
H Iwase ◽  
K Hotta ◽  
Y Tanaka ◽  
S Omura
Keyword(s):  
Enzyme Activity ◽  
Culture Medium ◽  
Gel Filtration ◽  
Partial Purification ◽  
Gastric Mucus ◽  
Purification And Characterization ◽  
Streptomyces Sp ◽  
Optimum Ph ◽  
New Type

For the purification of a new type of endo-alpha-N-acetylgalactosaminidase from the culture medium of Streptomyces sp. OH-11242 (endo-GalNAc-ase-S) [Iwase, Ishii, Ishihara, Tanaka, Omura & Hotta (1988) Biochem. Biophys. Res. Commun. 151, 422-428], a method for assaying enzyme activity was established. Using purified pig gastric mucus glycoprotein (PGM) as the substrate, oligosaccharides liberated from PGM were pyridylaminated, and the reducing terminal sugars of oligosaccharides larger than Gal beta 1-3GalNAc were analysed by h.p.1.c. The crude enzyme of endo-GalNAc-ase-S was prepared as an 80% (w/v) ammonium sulphate precipitate from the concentrated culture medium. The enzyme was partially purified by gel chromatofocusing and subsequent DEAE-Toyopearl chromatography. Endo-enzyme activity eluted around pI 4.8 on a gel chromatofocusing column and eluted with 0.19-0.25 M-NaCl on a DEAE-Toyopearl column. In the enzyme fraction obtained, no exo-glycosidases or proteases could be detected. The molecular mass of the enzyme was estimated as 105 kDa by gel filtration, and the optimum pH was 5.5. Endo-GalNAc-ase-S hydrolysed the O-glycosidic linkage between GalNAc and Ser (Thr) in 3H-labelled and unlabelled asialofetuin, liberating both the disaccharide (Gal beta 1-3GalNAc) and the tetrasaccharide [Gal beta 1-3 (Gal beta 1-4GlcNAc beta 1-6)GalNAc]. When endo-alpha-N-acetylgalactosaminidase from Alcaligenes sp. (endo-GalNac-ase-A) was incubated with 3H-labelled and unlabelled asialofetuin, only the disaccharide (Gal beta 1-3GalNAc) was liberated.

scholarly journals Occurrence of an endo-1,3-β-glucanase in culture fluids of the yeast Candida utilis. Purification and characterization of the enzyme activity

1979 ◽  
Vol 177 (1) ◽  
pp. 107-114 ◽  
Author(s):  
T G Villa ◽  
V Notario ◽  
J R Villanueva
Keyword(s):  
Enzyme Activity ◽  
Gel Electrophoresis ◽  
Candida Utilis ◽  
Culture Medium ◽  
Polyacrylamide Gel Electrophoresis ◽  
Gel Filtration ◽  
Polyacrylamide Gel ◽  
Beta Glucanase ◽  
Hydrolysis Of

The endo-1,3-beta-glucanase (EC 3.2.1.6) secreted into the culture medium by cells of Candida utilis was isolated and purified to homogeneity on polyacrylamide-gel electrophoresis and in ultracentrifugation studies (s20,w = 1.97S). The purified enzyme represented only 0.001% of the total 1,3-beta-glucanase activity, the remainder being due to an exo-1,3-beta-glucanase enzyme, and behaved as an acidic glycoprotein (pI 3.3) in isoelectric-focusing experiments. The mol.wt. was estimated to be 21 000 by gel filtration and polyacrylamide-gel electrophoresis. Studies on the hydrolysis of different substrates showed that the enzyme was only able to break down (1 leads to 3)-beta-linkages, by an endo-splitting mechanism. Glucono-delta-lactone, D-glucoronolactone and heavy metal ions such as Hg2+ were inhibitors of the enzyme activity. The function of this endo-beta-glucanase in C. utilis is discussed.

Control and localization of the phosphatases in conidia of Neurospora crassa

1989 ◽  
Vol 35 (9) ◽  
pp. 830-835 ◽  
Author(s):  
E. Nahas
Keyword(s):  
Alkaline Phosphatase ◽  
Enzyme Activity ◽  
Neurospora Crassa ◽  
Culture Medium ◽  
Alkaline Phosphatases ◽  
Cell Compartments ◽  
Surface Active Agents ◽  
Cell Enzyme ◽  
A Cell ◽  
Surface Active

Repressible acid, repressible alkaline, and constitutive alkaline phosphatases were studied with respect to their control and localization in conidia of Neurospora crassa. In contrast to constitutive alkaline phosphatase, the production and secretion of repressible phosphatases is regulated by phosphate level and pH of the culture medium. Phosphatase activity increased with conidial germination and was detectable partially in the growth medium after 5 h incubation. These enzymes were found to be located in different cell compartments. Part of the whole cell enzyme activity involved a soluble exoconidial fraction, and another part, a cell-bound enzyme that remained after successive washes. The cell-bound enzyme was sensitive to treatment with dilute acid and was thought to be located in the mural space. A third part of the enzyme activity was judged to be intracellular, as shown by treatments with surface-active agents and heat, which disrupted the conidia or destroyed the conidial permeability barriers. On the basis of these criteria, the constitutive alkaline phosphatase was considered to be more cryptic than the repressible phosphatases. The alkaline phosphatases were also active during heat treatment, suggesting they may be involved in the mechanism of secretion.Key words: Neurospora crassa, repressible acid phosphatase, repressible alkaline phosphatase, constitutive alkaline phosphatase, conidia.

Purification and some properties of the extracellular α-amylase from Aspergillus awamori

1985 ◽  
Vol 31 (2) ◽  
pp. 149-153 ◽  
Author(s):  
Resham S. Bhella ◽  
Illimar Altosaar
Keyword(s):  
Enzyme Activity ◽  
Gel Electrophoresis ◽  
Culture Medium ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Anion Exchange Chromatography ◽  
Exchange Chromatography ◽  
Aspergillus Awamori ◽  
Original Activity

Alpha-amylase was purified from the extracellular culture medium of Aspergillus awamori by means of ethanol precipitation. Sephacryl-200 gel filtration and anion-exchange chromatography on Dowex (AG1-X4) resin. The enzyme preparation was found to be homogeneous by means of sodium dodecyl sulfate–polyacrylamide gel electrophoresis. The purified enzyme had a molecular weight of 54 000 ± 2 500 and its isoelectric point was pH 4.2. The enzyme was found to be most active between pH 4.8 and 5.0 and was stable between pH 3.5 and 6.5. The optimal temperature for the enzyme activity was around 50 °C and the enzyme was stable for at least 1 h up to 45 °C retaining more than 80% of its original activity. The Km (37 °C, pH 5.3) for starch hydrolysis was 1.0 g∙L−1 and maltose inhibited the enzyme activity uncompetitively with a K1 value of 20.05 g∙L−1

scholarly journals Aspergillus niveus Blochwitz 4128URM: new source for inulinase production

2005 ◽  
Vol 48 (3) ◽  
pp. 343-350 ◽  
Author(s):  
Cristina Maria de Souza-Motta ◽  
Maria Auxiliadora de Queiroz Cavalcanti ◽  
Ana Lúcia Figueiredo Porto ◽  
Keila Aparecida Moreira ◽  
José Luiz de Lima Filho
Keyword(s):  
Enzyme Activity ◽  
Ammonium Sulphate ◽  
Crude Extract ◽  
Culture Medium ◽  
Food Industries ◽  
Ammonium Sulphate Precipitation ◽  
Aspergillus Niveus ◽  
Optimal Ph

Aspergillus niveus Blochwitz 4128 URM isolated from sunflower rhizosphere demonstrated a new source of inulinase. The enzyme was produced in culture medium containing inulin as substrate in the concentrations: 10, 15 and 20g L-1. Maximum enzyme activity was obtained in medium containing 20g L-1 inulin. The enzyme was partially purified using ammonium sulphate precipitation, followed by ion charge (DE-32) and molecular exclusion (Sephadex) chromatography. The results showed the optimal pH and temperature of inulinase from crude extract were 4.0 and 4.8 and 45ºC, respectively. The enzyme was purified 34.65 fold with yield of 53.63%. A. niveus 4128URM can be used in the inulinase production with use in the food industries.

scholarly journals Screening of cellulose-degrading fungi in forest litter and fungal effects on litter decomposition

BioResources ◽  
2020 ◽  
Vol 15 (2) ◽  
pp. 2937-2946
Author(s):  
Siqi Sun ◽  
Yuetai Weng ◽  
Xueying Di ◽  
Zhihua Liu ◽  
Guang Yang
Keyword(s):  
Culture Medium ◽  
Leaf Tissue ◽  
Forest Litter ◽  
Cellulolytic Enzymes ◽  
Juglans Mandshurica ◽  
Natural Cellulose ◽  
Congo Red Staining ◽  
Growth Of Fungi ◽  
Degradation Effect ◽  
Holocellulose Content

Fungi were isolated using a rose bengal chloramphenicol agar as the culture medium. Congo red staining was used on sodium carboxymethyl cellulose medium to screen fungal strains that have potential to produce cellulolytic enzymes according to the cellulolytic index (CI). The ability of these isolates to break down holocellulose in three forest litter substrates (broad-leafed: Juglans mandshurica; coniferous: Larix gmelinii; broadleaf-conifer mixed: J. mandshurica and L. gmelinii) was tested over 80 days of incubation. The holocellulose content and the decomposition rule were studied. The strain with the most efficient degradation effect on natural cellulose in forest litter was selected. The growth of fungi was observed by scanning electron microscopy (SEM). The hydrolytic circles indicated the activity of cellulase produced by the fungi, and it implied that the fungi could degrade cellulose. The results showed that eight strains were able to degrade cellulose. The strain A2 (Peniophora incarnate) showed the highest CI, while A4 (Sarocladium strictum) was most capable of degrading holocellulose in various litter substrates. The SEM micrographs revealed that A4 had the ability to invade leaf tissue and degrade holocellulose in leaves. This study could be helpful for forest litter management, which provides a new way to cleanup forest litter using cellulose-degrading fungi.

Ultrastructural Localization of Cellulase in Diplodia Maydis and in D. Maydis-Infected Com Stalk Tissue

1977 ◽  
Vol 35 ◽  
pp. 454-455
Author(s):  
Judith A. Murphy ◽  
Mary R. Thompson ◽  
A.J. Pappelis
Keyword(s):  
Culture Medium ◽  
Cupric Oxide ◽  
Cellulase Activity ◽  
Growth Period ◽  
Ultrastructural Localization ◽  
Ultrastructural Level ◽  
Low Ph ◽  
Cellulolytic Enzymes ◽  
Cellulolytic Activity ◽  
X Ray

BeMiller et.al.(l) found that D. maydis did not have the solubilizing enzyme C1. They reported that D- maydis exhibited cellulolytic activity constitutively, and hypothesized that the cellulolytic enzymes were attached to fungal hyphal surfaces because they found cellulase released to the culture medium only after the growth period, when available cellulose had been used up.The purpose of this study was to determine the location of cellulolytic enzymes (EC 3.2.1.4; beta-1,4-glucan glucanohydrolase) in D. maydis and D. maydis-infected corn tissue at the ultrastructural level.Cellulase activity produces glucose as an end product which will reduce cupric oxide and can be visualized with an EM because it is electron dense and the Cu component can be verified with x-ray analysis(Figs.l,2). After thorough washing, samples fixed in aldehydes are incubated in a substrate mixture at a low pH. The enzyme is activated and reducing sugar is released. The sample is then reacted with Benedict's solution at a high temperature, allowing CuO crystals to be deposited at the site of reaction.

scholarly journals Ionic Liquids Impact the Bioenergy Feedstock-Degrading Microbiome and Transcription of Enzymes Relevant to Polysaccharide Hydrolysis

mSystems ◽  
2016 ◽  
Vol 1 (6) ◽  
Author(s):  
Yu-Wei Wu ◽  
Brendan Higgins ◽  
Chaowei Yu ◽  
Amitha P. Reddy ◽  
Shannon Ceballos ◽  
...  
Keyword(s):  
Ionic Liquid ◽  
Enzyme Activity ◽  
Ionic Liquids ◽  
Microbial Community ◽  
Cellulolytic Enzymes ◽  
Future Research ◽  
Dynamic Changes ◽  
Complex Microbial Community ◽  
Enriched Cultures ◽  
Lignocellulose Hydrolysis

ABSTRACT Pretreatment using ionic liquids (IL) is a promising approach for the conversion of lignocellulose to biofuels. Because IL can be inhibitory to enzymes and microorganisms involved in downstream hydrolysis and fermentation steps, discovery of IL-tolerant organisms and enzymes is critical for advancing this technology. Employing metatranscriptomics in the analysis of IL-enriched cultures facilitated tracking of dynamic changes in a complex microbial community at the level of gene transcription and doing so with genome resolution. Specific organisms were discovered that could simultaneously tolerate a moderate IL concentration and transcribe a diverse array of cellulolytic enzymes. Gene sequences of cellulolytic enzymes and efflux pumps from those same organisms were also identified, providing important resources for future research on engineering IL-tolerant organisms and enzymes. Ionic liquid (IL) pretreatment is a promising approach for the conversion of lignocellulose to biofuels. The toxicity of residual IL, however, negatively impacts the performance of industrial enzymes and microorganisms in hydrolysis and fermentation. In this study, a thermophilic microbial community was cultured on switchgrass amended with various levels of the ionic liquid 1-ethyl-3-methylimidazolium acetate. Changes in the microbial community composition and transcription of genes relevant to IL tolerance and lignocellulose hydrolysis were quantified. Increasing the level of IL to 0.1% (wt) led to increased levels of relative abundance and transcription in organisms of the phylum Firmicutes. Interestingly, IL concentrations of up to 1% (wt) also resulted in greater xylanase transcription and enzyme activity as well as increased transcription of endoglucanase, beta-glucosidase, and IL tolerance genes compared to communities without IL. IL levels above 1% (wt) resulted in decreased enzyme activity and transcription of genes involved in lignocellulose hydrolysis. The results indicate that moderate levels of IL select for thermophilic microorganisms that not only tolerate IL but also effectively hydrolyze lignocellulose from switchgrass. Discovery of IL-tolerant organisms and enzymes is critical for the development of biological processes that convert IL-pretreated biomass to biofuels and chemicals. Employing metatranscriptomic analysis of enrichment cultures can facilitate the discovery of microorganisms and enzymes that may be active in the presence of toxic compounds such as ionic liquids. IMPORTANCE Pretreatment using ionic liquids (IL) is a promising approach for the conversion of lignocellulose to biofuels. Because IL can be inhibitory to enzymes and microorganisms involved in downstream hydrolysis and fermentation steps, discovery of IL-tolerant organisms and enzymes is critical for advancing this technology. Employing metatranscriptomics in the analysis of IL-enriched cultures facilitated tracking of dynamic changes in a complex microbial community at the level of gene transcription and doing so with genome resolution. Specific organisms were discovered that could simultaneously tolerate a moderate IL concentration and transcribe a diverse array of cellulolytic enzymes. Gene sequences of cellulolytic enzymes and efflux pumps from those same organisms were also identified, providing important resources for future research on engineering IL-tolerant organisms and enzymes.

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