Purification, characterization and mode of effect of another endo-D-galacturonanase from Aspergillus niger

1981 ◽  
Vol 46 (12) ◽  
pp. 3145-3156 ◽  
Author(s):  
Kvetoslava Heinrichová ◽  
Mária Dzúrová
Keyword(s):  
Molecular Weight ◽  
Aspergillus Niger ◽  
Degradation Products ◽  
Maximal Activity ◽  
Kinetic Constants ◽  
Pectic Acid ◽  
Commercial Preparation ◽  
Glycosidic Bonds ◽  
Pectolytic Enzymes ◽  
Approximate Molecular Weight

A mixture of pectolytic enzymes was isolated from a commercial preparation of Pectinex Ultra. endo-D-Galacturonanase (EC 3.2.1.15) was obtained from this mixture of enzymes, produced by Aspergillus niger cultures, by affinity chromatography using cross-linked pectic acid as a support and by subsequent chromatography on a Sephadex G-100 column. One form of endo-D-galacturonanase only of approximate molecular weight of 35 000 was detected in the purified product by electrophoresis in polyacrylamide gel. The enzyme showed maximal activity and stability at pH 4.9 and 40°. The mode of degradation of a high molecular weight substrate and the per cent of the glycosidic bonds cleaved (6%) at a viscosity decrease by 50% indicate an endo type action pattern. endo-D-Galacturonanase was characterized by the mode of cleavage and the kinetic constants Km and V for oligogalacturonic acids and polygalacturonic acid. On the basis of the knowledge of the kinetic constants and the degradation products the mode of action of the enzyme and the extent of its active site are discussed.

Antithrombin III Binding to Surface Immobilized Heparin and Its Relation to F Xa Inhibition

1987 ◽  
Vol 58 (04) ◽  
pp. 1064-1067 ◽  
Author(s):  
K Kodama ◽  
B Pasche ◽  
P Olsson ◽  
J Swedenborg ◽  
L Adolfsson ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Ionic Strength ◽  
Surface Coating ◽  
Antithrombin Iii ◽  
Lower Class ◽  
Biologically Active ◽  
High Affinity ◽  
Heparin Coating ◽  
Continuous Surface ◽  
Approximate Molecular Weight

SummaryThe mode of F Xa inhibition was investigated on a thromboresistant surface with end-point attached partially depoly-merized heparin of an approximate molecular weight of 8000. Affinity chromatography revealed that one fourth of the heparin used in surface coating had high affinity for antithrombin III (AT). The heparin surface adsorbed AT from both human plasma and solutions of purified AT. By increasing the ionic strength in the AT solution the existence of high and low affinity sites could be shown. The uptake of AT was measured and the density of available high and low affinity sites was found to be in the range of 5 HTid 11 pic.omoles/cmf, respectively Thus the estimated density of biologically active high and low ailmity heparm respectively would be 40 and 90 ng/cm2 The heparin coating did not take up or exert F Xa inhibition by itself. With AT adsorbed on both high and low affinity heparin the surface had the capacity to inhibit several consecutive aliquots of F Xa exposed to the surface. When mainly high affinity sites were saturated with AT the inhibition capacity was considerably lower. Tt was demonstrated that the density of AT on both high and low affinity heparin determines the F Xa inhibition capacity whereas the amount of AT on high affinity sites limits the rate of the reaction. This implies that during the inhibition of F Xa there is a continuous surface-diffusion of AT from sites of a lower class to the high affinity sites where the F Xa/AT complex is formed and leaves the surface. The ability of the immobilized heparin to catalyze inhibition of F Xa is likely to be an important component for the thromboresistant properties of a heparin coating with non-compromized AT binding sequences.

Permeability Enhancing and Chemotactic Activities of Lower Molecular Weight Degradation Products of Human Fibrinogen

1981 ◽  
Vol 45 (01) ◽  
pp. 090-094 ◽  
Author(s):  
Katsuo Sueishi ◽  
Shigeru Nanno ◽  
Kenzo Tanaka
Keyword(s):  
Molecular Weight ◽  
Degradation Products ◽  
Electron Microscopic Observation ◽  
Chemotactic Activity ◽  
Lower Molecular Weight ◽  
Electron Microscopic ◽  
Human Fibrinogen ◽  
Rabbit Skin ◽  
Molecular Weights ◽  
Active Fragments

SummaryFibrinogen degradation products were investigated for leukocyte chemotactic activity and for enhancement of vascular permeability. Both activities increased progressively with plasmin digestion of fibrinogen. Active fragments were partially purified from 24 hr-plasmin digests. Molecular weights of the permeability increasing and chemotactic activity fractions were 25,000-15,000 and 25,000 respectively. Both fractions had much higher activities than the fragment X, Y, D or E. Electron microscopic observation of the small blood vessels in rabbit skin correlated increased permeability with the formation of characteristic gaps between adjoining endothelial cells and their contraction.These findings suggest that lower molecular weight degradation products of fibrinogen may be influential in contributing to granulocytic infiltration and enhanced permeability in lesions characterized by deposits of fibrin and/or fibrinogen.

Polysaccharides from the Flowers of Malva silvestris L., ssp. mauritiana (L.) THELL.: The Structure of D-Glucan

1992 ◽  
Vol 57 (11) ◽  
pp. 2400-2406 ◽  
Author(s):  
Peter Capek
Keyword(s):  
Molecular Weight ◽  
Ion Exchange ◽  
Average Molecular Weight ◽  
Linear Structure ◽  
Gel Chromatography ◽  
Spectroscopic Investigations ◽  
Glycosidic Bonds

The neutral polysaccharide α-D-glucan was isolated from the flowers of Malva silvestris L., ssp. mauritiana (L.) THELL. using a combination of ion exchange and gel chromatography. It was homogeneous under the conditions of free electrophoresis of average molecular weight Mn 25260. The chemical and spectroscopic investigations indicated a linear structure of the polysaccharide in which the α-D-glucopyranose units were linked predominantly by 1→6 glycosidic bonds, while some saccharides were the place of branching in position C-3.

Optimization of the decolorization conditions of Rose Bengal by using Aspergillus niger TF05 and a decolorization mechanism

Microbiology ◽  
2022 ◽  
Vol 168 (1) ◽  
Author(s):  
Minghui Zhou ◽  
Yan Zhang ◽  
Yajun Chen ◽  
Fangyan Zhang ◽  
Daihu Yang
Keyword(s):  
Aspergillus Niger ◽  
Ammonium Chloride ◽  
Rose Bengal ◽  
Metal Ion ◽  
Degradation Products ◽  
Uniform Design ◽  
Nitrogen Sources ◽  
Spore Concentration ◽  
Rose Bengal Dye ◽  
Burman Design

Aspergillus niger TF05 was applied to decolorize Rose Bengal dye. The effects of carbon source, nitrogen source, metal ion and spore concentration on Rose Bengal treatment with A. niger TF05 were studied. A Plackett–Burman design (PBD) and a uniform design (UD) were used to optimize the decolorization conditions of A. niger TF05 and enhance its decolorization effect. The mechanism of Rose Bengal decolorization by A. niger TF05 was examined by analysing degradation products via UV–visible light spectroscopy, IR spectroscopy and GC-MS. The best decolorization effect was achieved in the single factor test with glucose and ammonium chloride as carbon and nitrogen sources, respectively. Mg2+ was an essential ion that could improve the mould ball state and adsorption efficiency if the spore concentration was maintained at 106 spores ml–1. The optimal decolorization conditions obtained using the PBD and UD methods were 11.5 g l−1 glucose, 6.5 g l−1 ammonium chloride, 0.4 g l−1 magnesium sulphate, pH 5.8, 28 °C, 140 r.p.m. rotational speed, 0.18 g l−1 dye concentration, 0.5 ml of inocula and 120 h decolorization time. Under these conditions, the maximum decolorization rate was 106%. Spectral analysis suggested that the absorption peak of the product changed clearly after decolorization; GC-MS analysis revealed that the intermediate product tetrachlorophthalic anhydride formed after decolorization. The combined use of the PBD and UD methods can optimize multi-factor experiments. A. niger TF05 decolorized Rose Bengal during intracellular enzymatic degradation after adsorption.

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 Solubility and ADMET profiles of short oligomers of lactic acid

ADMET & DMPK ◽  
2020 ◽  
Author(s):  
Daniela Dascălu ◽  
Diana Larisa Roman ◽  
Madalina Filip ◽  
Alecu Aurel Ciorsac ◽  
Vasile Ostafe ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Glucocorticoid Receptors ◽  
Degradation Products ◽  
Organic Anion ◽  
Toxicity Tests ◽  
Medical Applications ◽  
Eye Injuries ◽  
Toxicological Effects

<p class="ADMETkeywordsheading">Polylactic acid (PLA) is a polymer with an increased potential to be used in different medical applications, including tissue engineering and drug-carries. The use of PLA in medical applications implies the evaluation of the human organism's response to the polymer inserting and to its degradation products. Consequently, within this study, we have investigated the solubility and ADMET profiles of the short oligomers (having the molecular weight lower than 3000 Da) resulting in degradation products of PLA. There is a linear decrease of the molar solubility of investigated oligomers with molecular weight. The results that are obtained also reveal that short oligomers of PLA have promising pharmacological profiles and limited toxicological effects on humans. These oligomers are predicted as potential inhibitors of the organic anion transporting peptides OATP1B1 and OATP1B3, they present minor probability to affect the androgen and glucocorticoid receptors, have a weak potential of hepatotoxicity, and may produce eye injuries. These outcomes may be used to guide or to supplement in vitro and/or in vivo toxicity tests such as to enhance the biodegradation properties of the biopolymer.</p>

Instabilities in the System NMMO/Water/Cellulose (Lyocell Process) Caused by Polonowski Type Reactions

Holzforschung ◽  
2002 ◽  
Vol 56 (2) ◽  
pp. 199-208 ◽  
Author(s):  
Thomas Rosenau ◽  
Antje Potthast ◽  
Andreas Hofinger ◽  
Herbert Sixta ◽  
Paul Kosma
Keyword(s):  
Molecular Weight ◽  
Acetic Acid ◽  
Exchange Resin ◽  
Degradation Products ◽  
Ion Exchange Resin ◽  
Low Molecular Weight ◽  
Acid Component ◽  
Degradation Reactions ◽  
Polyglucuronic Acid

Summary Polonowski type degradation reactions are a major reason for the frequently observed instability of solutions of cellulose in N-methylmorpholine-N-oxide monohydrate (NMMO, 1). The degradation is induced by degradation products of cellulose and NMMO generated in situ in the Lyocell system. The presence of both an amine component, such as morpholine or N-methylmorpholine, and an acid component is required for the decomposition process to proceed. The latter might be a low-molecular-weight compound, such as formic acid, acetic acid or gluconic acid, or also a high-molecular-weight acid, such as polyglucuronic acid or ion exchange resin.

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