scholarly journals Characterization of a Novel β-Galactosidase fromBifidobacterium adolescentis DSM 20083 Active towards Transgalactooligosaccharides

2000 ◽  
Vol 66 (4) ◽  
pp. 1379-1384 ◽  
Author(s):  
Katrien M. J. Van Laere ◽  
Tjakko Abee ◽  
Henk A. Schols ◽  
Gerrit Beldman ◽  
Alphons G. J. Voragen

ABSTRACT This paper reports on the effects of both reducing and nonreducing transgalactooligosaccharides (TOS) comprising 2 to 8 residues on the growth of Bifidobacterium adolescentis DSM 20083 and on the production of a novel β-galactosidase (β-Gal II). In cells grown on TOS, in addition to the lactose-degrading β-Gal (β-Gal I), another β-Gal (β-Gal II) was detected and it showed activity towards TOS but not towards lactose. β-Gal II activity was at least 20-fold higher when cells were grown on TOS than when cells were grown on galactose, glucose, and lactose. Subsequently, the enzyme was purified from the cell extract of TOS-grown B. adolescentis by anion-exchange chromatography, adsorption chromatography, and size-exclusion chromatography. β-Gal II has apparent molecular masses of 350 and 89 kDa as judged by size-exclusion chromatography and sodium dodecyl sulfate-polyacrylamide gel electrophoresis, respectively, indicating that the enzyme is active in vivo as a tetramer. β-Gal II had an optimal activity at pH 6 and was not active below pH 5. Its optimum temperature was 35°C. The enzyme showed highestV max values towards galactooligosaccharides with a low degree of polymerization. This result is in agreement with the observation that during fermentation of TOS, the di- and trisaccharides were fermented first. β-Gal II was active towards β-galactosyl residues that were 1→4, 1→6, 1→3, and 1↔1 linked, signifying its role in the metabolism of galactooligosaccharides by B. adolescentis.

1986 ◽  
Vol 32 (2) ◽  
pp. 167-175 ◽  
Author(s):  
Richard E. Scott ◽  
K. S. Lam ◽  
G. M. Gaucher

m-Hydroxybenzylalcohol dehydrogenase (EC 1.1.1.97), a secondary metabolism associated protein from stationary phase cultures of Penicillium urticae, was stabilized in crude extracts prior to purification. Stabilization studies resulted in the formulation of an optimal cell breakage and purification buffer. This buffer increased the enzyme's in vitro half-life at 30 °C from 14 to over 800 min which greatly aided purification and enhanced yields. Purification was achieved by salt fractionation, size-exclusion chromatography, affinity chromatography, and ion-exchange chromatography. The 1200-fold purified protein gave only one major band by sodium dodecyl sulphate – polyacrylamide gel electrophoresis.


2021 ◽  
Vol 65 (1) ◽  
pp. 65-73
Author(s):  
Isaiah O. Adedoyin ◽  
Taiwo S. Adewole ◽  
Titilayo O. Agunbiade ◽  
Francis B. Adewoyin ◽  
Adenike Kuku

This study investigated the larvicidal activity on Culex quinquefasciatus of lectin purified from fresh fruiting bodies of woodland mushroom, Agaricus semotus. A. semotus lectin (ASL) was purified via ion-exchange chromatography on DEAE-cellulose A-25 and size exclusion chromatography on Sephadex G-100 matrix. Molecular weight (16.6 kDa) was estimated by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). The effects of temperature, pH, metal chelation- and larvicidal activity of ASL were also investigated. The ASL indifferently agglutinated the erythrocytes of the human ABO blood system and was stable at acidic pH and below 50 °C whereas 66% of its activity was lost at 60 °C with complete inactivation at 70 °C. ASL is a metalloprotein requiring barium ion as chelation of metals by 50 mM EDTA rendered the lectin inactive, while the addition of BaCl2, among other metal salts, restored the activity. ASL showed larvicidal activity against C. quinquefasciatus larvae after 24 h with a mortality of 5 and 95% at 5 and 25 mg/mL respectively, and LC50 of 13.80 mg/mL. This study concluded that purified A. semotus lectin showed impressive larvicidal activity, which could be exploited in its development as an insecticidal agent.


2021 ◽  
Vol 22 (9) ◽  
pp. 4512
Author(s):  
Michał Marcinkowski ◽  
Tomaš Pilžys ◽  
Damian Garbicz ◽  
Jan Piwowarski ◽  
Damian Mielecki ◽  
...  

The FTO protein is involved in a wide range of physiological processes, including adipogenesis and osteogenesis. This two-domain protein belongs to the AlkB family of 2-oxoglutarate (2-OG)- and Fe(II)-dependent dioxygenases, displaying N6-methyladenosine (N6-meA) demethylase activity. The aim of the study was to characterize the relationships between the structure and activity of FTO. The effect of cofactors (Fe2+/Mn2+ and 2-OG), Ca2+ that do not bind at the catalytic site, and protein concentration on FTO properties expressed in either E. coli (ECFTO) or baculovirus (BESFTO) system were determined using biophysical methods (DSF, MST, SAXS) and biochemical techniques (size-exclusion chromatography, enzymatic assay). We found that BESFTO carries three phosphoserines (S184, S256, S260), while there were no such modifications in ECFTO. The S256D mutation mimicking the S256 phosphorylation moderately decreased FTO catalytic activity. In the presence of Ca2+, a slight stabilization of the FTO structure was observed, accompanied by a decrease in catalytic activity. Size exclusion chromatography and MST data confirmed the ability of FTO from both expression systems to form homodimers. The MST-determined dissociation constant of the FTO homodimer was consistent with their in vivo formation in human cells. Finally, a low-resolution structure of the FTO homodimer was built based on SAXS data.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Nicole L. McIntosh ◽  
Geoffrey Y. Berguig ◽  
Omair A. Karim ◽  
Christa L. Cortesio ◽  
Rolando De Angelis ◽  
...  

AbstractAdeno associated virus (AAV) capsids are a leading modality for in vivo gene delivery. Complete and precise characterization of capsid particles, including capsid and vector genome concentration, is necessary to safely and efficaciously dose patients. Size exclusion chromatography (SEC) coupled to multiangle light scattering (MALS) offers a straightforward approach to comprehensively characterize AAV capsids. The current study demonstrates that this method provides detailed AAV characterization information, including but not limited to aggregation profile, size-distribution, capsid content, capsid molar mass, encapsidated DNA molar mass, and total capsid and vector genome titer. Currently, multiple techniques are required to generate this information, with varying accuracy and precision. In the current study, a new series of equations for SEC-MALS are used in tandem with intrinsic properties of the capsids and encapsidated DNA to quantify multiple physical AAV attributes in one 20-min run with minimal sample manipulation, high accuracy, and high precision. These novel applications designate this well-established method as a powerful tool for product development and process analytics in future gene therapy programs.


2020 ◽  
Vol 10 (8) ◽  
pp. 2648 ◽  
Author(s):  
Paolina Lukova ◽  
Mariana Nikolova ◽  
Emmanuel Petit ◽  
Redouan Elboutachfaiti ◽  
Tonka Vasileva ◽  
...  

The aim of the present study was to evaluate the prebiotic potential of Plantago major L. leaves water-extractable polysaccharide (PWPs) and its lower molecular fractions. The structure of PWPs was investigated by high pressure anion exchange chromatography (HPAEC), size exclusion chromatography coupled with multi-angle laser light scattering detector (SEC-MALLS) and Fourier-transform infrared (FTIR) spectroscopy. The chemical composition and monosaccharide analyses showed that galacturonic acid was the main monosaccharide of PWPs followed by glucose, arabinose, galactose, rhamnose and xylose. FTIR study indicated a strong characteristic absorption peak at 1550 cm−1 corresponding to the vibration of COO− group of galacturonic acid. The PWPs was subjected to hydrolysis using commercial enzymes to obtain P. major low molecular fraction (PLM) which was successively separated by size exclusion chromatography on Biogel P2. PWPs and PLM were examined for in vitro prebiotic activity using various assays. Results gave evidence for changes in optical density of the bacteria cells and pH of the growth medium. A heterofermentative process with a lactate/acetate ratio ranged from 1:1 to 1:5 was observed. The ability of PLM to stimulate the production of certain probiotic bacteria glycohydrolases and to be fermented by Lactobacillus sp. strains was successfully proved.


Molecules ◽  
2020 ◽  
Vol 25 (3) ◽  
pp. 472
Author(s):  
Richard Marchal ◽  
Thomas Salmon ◽  
Ramon Gonzalez ◽  
Belinda Kemp ◽  
Céline Vrigneau ◽  
...  

Botrytis cinerea is a fungal pathogen responsible for the decrease in foamability of sparkling wines. The proteolysis of must proteins originating from botrytized grapes is well known, but far less information is available concerning the effect of grape juice contamination by Botrytis. The impact from Botrytis on the biochemical and physico-chemical characteristics of proteins released from Saccharomyces during alcoholic fermentation remains elusive. To address this lack of knowledge, a model grape juice was inoculated with three enological yeasts with or without the Botrytis culture supernatant. Size exclusion chromatography coupled to multi-angle light scattering (SEC-MALLS) and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) techniques (AgNO3 and periodic acid Schiff staining) was used in the study. When Botrytis enzymes were present, a significant degradation of the higher and medium MW molecules released by Saccharomyces was observed during alcoholic fermentation whilst the lower MW fraction increased. For the three yeast strains studied, the results clearly showed a strong decrease in the wine foamability when synthetic musts were inoculated with 5% (v/v) of Botrytis culture due to fungus proteases.


Nanoscale ◽  
2018 ◽  
Vol 10 (16) ◽  
pp. 7420-7430 ◽  
Author(s):  
Sean F. Gilmore ◽  
Timothy S. Carpenter ◽  
Helgi I. Ingólfsson ◽  
Sandra K. G. Peters ◽  
Paul T. Henderson ◽  
...  

Nanolipoprotein assembly, and dissociation through contact with serum, as assessed through size-exclusion chromatography.


Holzforschung ◽  
2004 ◽  
Vol 58 (1) ◽  
pp. 97-104 ◽  
Author(s):  
B. Saake ◽  
S. Lebioda ◽  
J. Puls

Abstract Four methyl cellulose samples in the degree of substitution range from 0.5 to 2.0 were characterised by combination of different analytical methods. Samples were analysed regarding their partial degree of substitution by hydrolysis and anion exchange chromatography with pulsed amperometric detection. For calibration of the chromatographic system, standard substances were isolated by preparative HPLC and their structure was confirmed by 13C-NMR spectroscopy. For two methyl cellulose samples per-acetylation and 13C-NMR with inverse gated decoupling was carried out for comparison with the chromatographic analysis. Endoglucanase fragmentation of methyl celluloses was performed and water-soluble and insoluble fractions were analysed separately. A preparative size exclusion chromatography system for enzymatic-degraded water-soluble methyl cellulose was developed and the molar masses of the individual fractions were examined by analytical size exclusion chromatography. By combination of endoglucanase fragmentation, preparative chromatography, hydrolysis and anion exchange chromatography an approach for the analysis of the substitutent distribution along the polymeric chain of water-soluble methyl cellulose could be established.


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