DEGRADATION OF THE POLYSACCHARIDE OF XANTHOMONAS PHASEOLI BY AN EXTRACELLULAR BACTERIAL ENZYME

1961 ◽  
Vol 7 (5) ◽  
pp. 815-825 ◽  
Author(s):  
S. M. Lesley
Keyword(s):  
Molecular Weight ◽  
Glucuronic Acid ◽  
Degradation Products ◽  
Extracellular Enzyme ◽  
Low Molecular Weight ◽  
Acid Moiety ◽  
Ph Optimum ◽  
Polysaccharide Degradation ◽  
Bacterial Enzyme ◽  
Stability Examination

A species of Bacillus isolated from soil was found to elaborate an inducible, extracellular enzyme capable of degrading the polysaccharide of Xanthomonas phaseoli to low-molecular-weight oligosaccharides. The enzyme was characterized with respect to pH optimum, ion requirement, and stability. Examination of the polysaccharide degradation products revealed that the glucuronic acid moiety of the polysaccharide was altered to a Δ4,5 unsaturated form as a result of enzyme action.

THE ACTION OF LIQUID AMMONIA ON WHEAT STRAW HOLOCELLULOSE

1952 ◽  
Vol 30 (4) ◽  
pp. 229-234 ◽  
Author(s):  
C. T. Bishop
Keyword(s):  
Molecular Weight ◽  
Wheat Straw ◽  
Liquid Ammonia ◽  
Glucuronic Acid ◽  
Degradation Products ◽  
Separate Experiment ◽  
Low Molecular Weight ◽  
Molar Ratios ◽  
Exhaustive Extraction

Exhaustive extraction with anhydrous liquid ammonia removed 8.0% of wheat straw holocellulose. Acetamide was isolated from the extract and identified as the dihydrogen bromide salt. A polyuronide fraction, making up 1.3% of the holocellulose, was isolated and shown to consist of D-xylose, L-arabinose, D-glucose, D-galactose, and D-glucuronic acid in approximate molar ratios of 11:3:3:1:2.5. Analysis and hydrogenation of the noncarbohydrate portion of the liquid ammonia extract showed it to consist of low molecular weight degradation products among which methylamine was identified. A separate experiment showed that anhydrous liquid ammonia degraded an isolated polyuronide by 8.4%; all components of the polyuronide were equally affected.

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.

Seasonal changes in the chemical composision of the red alga Hypnea musciformis

1973 ◽  
Vol 24 (3) ◽  
pp. 275
Author(s):  
AF Abdel ◽  
NM Abed ◽  
M Edrees
Keyword(s):  
Amino Acids ◽  
Molecular Weight ◽  
Chemical Composition ◽  
Seasonal Changes ◽  
Free Amino ◽  
Glucuronic Acid ◽  
Red Alga ◽  
Low Molecular Weight ◽  
Hypnea Musciformis ◽  
Algal Material

Seasonal changes were observed in the chemical composition of the marine red alga Hypnea musciformis. Lipids, cholesterol, and lanosterol were found as constituents of the algal material. No low-molecular weight carbohydrates were found except small amounts of mannitol. The algal hydrolysate was shown to contain galactose, glucose, and xylose in all seasons and was characterized by a high content of glucuronic acid and its lactone in February. Definite seasonal variations were found in the patterns of free amino acids and of amino acid compositions of proteins.

BINDING AND METABOLISM OF HEPARIN BY ENDOTHELIAL CELLS

1987 ◽  
Author(s):  
S Vannucchi ◽  
F Pasquali ◽  
P Bianchi-ni ◽  
M Ruggiero
Keyword(s):  
Molecular Weight ◽  
Endothelial Cells ◽  
De Novo ◽  
Degradation Products ◽  
Low Molecular Weight ◽  
Competition Binding ◽  
Capillary Endothelial Cells ◽  
A Site ◽  
Binding Sequence

In this study we show that bovineadrenal capillary endothelial cells(BACE) contain heparin (HP); this HP has been found associated with the cell surface (i.e; trypsin-removable^and intracellularly. How-ever, experiments with [ sjsodium sulfate labelling, demonstrate that BACE cells donot synthesize HP de novo, but they uptake it from serum. We have studied binding, uptake, and metabolism odifferent molecular weight-HPs: 13 Kd-HP from bovine source, 14 Kd-HP from porcine source, 4.5 Kd, and 2.5-HP fragments. Comparison among different HPs, was carried out by calculating the IC from competition curves for [3HJ- HP. Binding of labelled-HP to BACE cells was specificand saturable. Dextran sulfate and glycosaminoglycans did not compete for binding; only heparan sulfate showed some competition. Binding of different HPs was strictly dependent on their molecular weight; 2.5 Kd- HP was unable to bind to cells, although sulfation degree of this fragment and of unfractionated HP was almost identical. Therefore, we assume that a specific oligosaccharide sequence could be responsible for HP binding to BACE cells; this hypothetical "binding sequence" could then be lost in very low molecular weight-HP fragments. BACE cells are also able to internalize HP, and they release its low molecular weight degradation products into culture medium. Thus we suggest that endothelial cells might represent a site for the metabolism of endogenous and exogenous HP in vivo.

Extracellular alkaline phosphatase from alveolar secretions of patients with pulmonary alveolar proteinosis

1981 ◽  
Vol 59 (4) ◽  
pp. 290-300 ◽  
Author(s):  
Denis Nadeau ◽  
Mark J. Reasor ◽  
Gary E. R. Hook
Keyword(s):  
Molecular Weight ◽  
Alkaline Phosphatase ◽  
Pulmonary Alveolar Proteinosis ◽  
Extracellular Enzyme ◽  
Soluble Form ◽  
Kinetic Properties ◽  
Ph Optimum ◽  
High Molecular Weight Complex ◽  
Heat Stable ◽  
Alveolar Proteinosis

Alkaline phosphatases in alveolar secretions from the lungs of patients with pulmonary alveolar proteinosis have been studied. A soluble form of alkaline phosphatase was isolated from the secretions and characterized. The extracellular enzyme had a pH optimum at 9.95; was stimulated by Mg2+, Ni2+, and Mn2+; was inhibited by Zn2+, Be2+, Cu2+, and low concentrations (8 mM) of L-homoarginine and imidazole; and was heat-stable at 55 °C. The soluble phosphatase existed primarily as a high molecular weight complex (excluded from Sepharose 4B) and could be dispersed into low molecular weight forms (205 000 – 285 000) by treatment with n-butanol. Following butanol treatment, the thermostability of the enzyme was markedly decreased but the kinetic properties such as the Km values, activation energies, and responses to various inhibitors were unchanged.The alkaline phosphatase may originate from unusual type 2 cells present in the alveoli of patients with pulmonary alveolar proteinosis.

scholarly journals ДІЄТИЧНА ДОБАВКА ІМУНОТРОПНОЇ ДІЇ НА ОСНОВІ ПРОДУКТІВ ДЕСТРУКЦІЇ ПРОБІОТИЧНИХ БАКТЕРІАЛЬНИХ КУЛЬТУР

2018 ◽  
Vol 82 (1) ◽  
Author(s):  
Антоніна Іванівна Капустян ◽  
Наталля Кирилівна Черно
Keyword(s):  
Molecular Weight ◽  
Dietary Supplement ◽  
Bacterial Cell ◽  
Degradation Products ◽  
General Scheme ◽  
Animal Experiments ◽  
Reaction Medium ◽  
Low Molecular Weight ◽  
Toxic Substances ◽  
Absorption Bands

У роботі розглянуто можливість отримання імунотропної дієтичної добавки на основі низькомолекулярних продуктів деградації пептидогліканів клітинних стінок пробіотичних бактерій. Встановлено раціональні режими автолізу біомаси як первинного етапу деструкції пептидогліканів бактеріальних клітинних стінок. Показано, що найбільш інтенсивний лізис клітин відбувається при експозиції культуральної рідини при 90°C протягом 15 хв після 8-ї години культивування, про що свідчить максимальне накопичення амінокислот у реакційному середовищі (1,8 мг/см3). Проведено оптимізацію процесу деструкції пептидогліканів бактеріальних клітин, які піддавали лізису, ферментним препаратом панкреатином. Ефективність ферментолізу визначали за накопиченням імунотропних низькомолекулярних пептидів залежно від концентрації ферменту (СЕ), субстрату (СS) в реакційній суміші та тривалості процесу (τ). Встановлено, що раціональний режим ферментолізу, який забезпечує максимальне накопичення низькомолекулярних пептидів (0,569 мг/см3, досягається за наступних значень факторів: СЕ=12,5 мг/см3, СS=70,0 мг/см3, τ=245,6 хв. Зразок низькомолекулярних пептидів, отриманий за раціональних режимів деструкції, досліджено методом ІЧ-спектроскопії. Встановлено, що у його ІЧ-спектрі присутні смуги поглинання, які відповідають коливанням аміногруп, пептидних зв’язків, піранозної форми глюкози, залишки якої входять до складу мурамової кислоти, та N-ацетилглюкозаміну пептидоглікану. Приведено загальну схему, що ілюструє послідовність процесів виробництва імунотропної дієтичної добавки .У дослідах на щурах встановлено ефективну дозу отриманої дієтичної добавки –0,06 мг/кг маси тіла.  The possibility of obtaining an immunotropic dietary supplement based on low molecular weight degradation products of cell wals peptidoglycans of lactic and bifidobacteria composition has been considered. Rational regimes of autolysis of biomass as the primary stage of degradation of peptidoglycans of bacterial cell walls have been established. It was shown that the most intensive lysis of cells takes place when the culture liquid is treated at a temperature of 90 °C for the 8th hour of cultivation, as indicated by the maximum accumulation of amino acids in the reaction medium (1.8 mg/cm3). Optimization of the destruction process of bacterial cell peptidoglycans exposed to lysis, by enzyme preparation with pancreatin, was carried out by the mathematical planning method of the multifactorial experiment. The effectiveness of enzymatic hydrolysis was determined by the accumulation of immunotropic low molecular weight peptides, depending on the concentration of the enzyme (CE), the substrate (CS) in the reaction mixture and the duration of the process (τ). The rational value of the factors CE, CS and τ that provide the maximum concentration of low molecular weight peptides (0.569 mg/cm3) in the enzymatic hydroltsate are CE=12.5 mg/cm3, Cs=70.0 mg/cm3, τ=245.6 min. A sample of low molecular weight peptides obtained from rational degradation regimes was investigated using the IR spectroscopy method. It has been established that in its spectrum absorption bands corresponding to fluctuations of amino groups, peptide bonds are presentred, which, in fact, take place in the structure of peptides. Fluctuations of the pyranose glucose form, which is included in the muramic acid and N-acetylglucosamine of peptidoglycan, have also been observed. The general scheme of the sequence of production processes of an immunotropic dietary supplement has been given. In animal experiments, it has been established that this additive, in accordance with the classification of chemicals substances to the degree of danger, belongs to class 4 (low-toxic substances). The effective dose of the obtaned dietary supplement is 0.06 mg/kg body weight.

scholarly journals Products of Metabolism and Processing of Lactic Acid Bacteria as Functional Ingredients

2018 ◽  
Vol 1 (1) ◽  
pp. 47 ◽  
Author(s):  
Antonina Ivanovna Kapustian ◽  
Natalia Cherno ◽  
Alexei Kovalenko ◽  
Kristina Naumenko ◽  
Igor Kushnir
Keyword(s):  
Amino Acids ◽  
Molecular Weight ◽  
Lactic Acid ◽  
Lactic Acid Bacteria ◽  
Organic Acids ◽  
Cell Walls ◽  
Degradation Products ◽  
Lactobacillus Delbrueckii ◽  
Low Molecular Weight ◽  
Gel Chromatography

Lactic acid bacteria (LAB) and bifidobacteria (BB) are unique substances that have a lot of biological and physiological effects. Structural components of LAB and BB – peptidoglycans, compounds of the muramylpeptide series, teichoic acids – have powerful immunological properties. Metabolites of LAB and BB – organic acids, hydrogen peroxide, bacteriocins, etc. – provide antagonistic activity, have an indirect impact on the immune system, reducing the antigenic load caused by pathogenic microorganisms. The expediency of peptidoglycans degradation of LAB and BB cell walls is substantiated. Low molecular weight products of the degradation can easily be absorbed and enter into biochemical processes, accelerating the expected functional-physiological effect. To obtain low-molecular products of peptidoglycans degradation, a combination of LAB and BB was used. The combination of LAB and BB is the sum of the test cultures of Lactobacillus acidophilus, Lactobacillus delbrueckii subsp. Bulgaricus, Bifidobacterium bifidum, Lactococcus cremoris, Streptococcus termophilus. Destruction of peptidoglycans of bacterial cell walls was carried out using a combination of disintegrating factors. The efficiency of destruction was determined by the accumulation of low molecular weight peptides (with molecular weight up to 1500 Da), amino acids and soluble protein in the disintegrate. It has been established that the highest accumulation of low molecular weight degradation products occurs when using autolysis followed by enzymatic hydrolysis during 180 min with the ratio of the enzyme : substrate 1 : 100. At the same time ≈ 53% of protein substances pass from insoluble to soluble state. The molecular weight of the obtained products is determined by the gel chromatography method. The qualitative and quantitative content of organic acids, amino acids and vitamins of group В in the hydrolysis products composition was investigated. It was shown that the obtained product possesses high biological effect in the experiment on animals.

Kinin-like Activities of the Synthetic Low Molecular Weight Fragment of Fibrinogen Degradation Products

1974 ◽  
Vol 32 (02/03) ◽  
pp. 350-355
Author(s):  
Akira Takaki ◽  
Tsuyoshi Yamaguchi ◽  
Keiichi Ohsato
Keyword(s):  
Molecular Weight ◽  
Smooth Muscle ◽  
Muscle Contraction ◽  
Synthetic Peptide ◽  
Degradation Products ◽  
Hypotensive Effect ◽  
Smooth Muscle Contraction ◽  
Biological Properties ◽  
Low Molecular Weight ◽  
Fibrinogen Degradation Products

SummarySome biological properties of a synthetic peptide based on an anticoagulant peptide obtained from fibrinogen degradation products by the action of plasmin are reported. This peptide produced smooth muscle contraction without the presence of bradykinin. The contraction caused by this peptide was not modified by atropin (10-6 g/ml), hyoscine (10-6 g/ml) and tetrodotoxin (2xl0-7 g/ml). A hypotensive effect was observed following the intravenous injection of the peptide into an anesthetized rat indicating that this peptide has an action similar to that of bradykinin though less potent.

Low Molecular Weight Fibrinogen Degradation Products Stimulate the Release of Growth Factors from Endothelial Cells

1992 ◽  
Vol 68 (03) ◽  
pp. 357-363 ◽  
Author(s):  
Roberto Lorenzet ◽  
Joan H Sobel ◽  
Alessandra Bini ◽  
Larry D Witte
Keyword(s):  
Molecular Weight ◽  
Endothelial Cells ◽  
Growth Factors ◽  
Degradation Products ◽  
Cell Damage ◽  
Low Molecular Weight ◽  
Aortic Endothelial Cells ◽  
Fibrinogen Degradation Products ◽  
3T3 Fibroblasts ◽  
Growth Assay

SummaryCultured porcine aortic endothelial cells (PAEC) constitutively produce and secrete in their culture medium mitogens collectively called endothelial cell-derived growth factors (EDGFs). Incubation of PAEC with fibrinogen-degradation products (FDPs) obtained by plasmin digestion of highly purified fibrinogen caused an increased release of EDGFs, as assessed by [3H]-thymidine incorporation in 3T3 mouse fibroblasts. The effect was time-dependent and correlated with the degree of fibrinogenolysis. It was accompanied by elongation of the cells. Neither increase in EDGFs release nor cell damage was observed when non-degraded fibrinogen was incubated with endothelial cells. Low molecular weight fibrinogen degradation products (LMWFDPs) (M r ≤ 10,000), and the higher molecular weight fibrinogen fragments D and E were tested under the same conditions. Only the LMWFDPs caused elongation and damage to PAEC and a marked stimulation (up to 12 fold) of EDGFs release. A low density growth assay revealed that the released EDGFs were mitogenically active on the same PAEC. The activity of the released EDGFs was time and dose dependent on both 3T3 fibroblasts and PAEC, indicating that LMWFDPs caused enhanced release of EDGFs that can act in paracrine and autocrine fashion. This study suggests an additional role for fibrinogenolysis contributing to wound healing, and possibly to atherosclerosis.

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