Wyniki wyszukiwania - Biblioteka Nauki

1

Surface tension of sodium dodecyl sulphate in the presence of a simple electrolyte

100%

Adamczyk Z. , Para G. , Warszyński P.

Bulletin of the Polish Academy of Sciences. Chemistry

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1999

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tom Vol. 47, No. 2

175-186

EN

Surface tension of aqueous solutions of sodium dodecyl sulphate (SDS) was measured by the drop-weight method, at various KCl concentrations. A significant reduction of the solution surface tension was observed with increasing electrolyte concentration in accordance with previous literature data obtained for NaCl. The experimental results were quantitatively interpreted in terms of the new theoretical model based on the as-sumption that the counterions penetrate the Stern layer and undergo specific adsorption there. The model proved superior over previously used in the literature reflecting well both the experimental surface tension data and the diffuse double layer potentials.

2

Analysis of the low molecular weight nuclear polypeptide by isoelectrofocusing of nuclear proteins first separated by gel electrophoresis in SDS

88%

Borowicz B. , Domaniewski J.

Archivum Veterinarium Polonicum

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1994

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tom 34

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nr 3-4

3

Foaming properties of selected surfactants

75%

Wieczorek D. , Michocka K.

Towaroznawcze Problemy Jakości. Polskie Towarzystwo Towaroznawcze

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2015

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nr 1

4

The interaction between some serine proteinases and horse leucocyte inhibitor

75%

Dubin A. , Potempa J. , Turyna B.

Folia Histochemica et Cytobiologica

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1986

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tom 24

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nr 2

5

Does the peroxidase-like activity of sodium dodecyl sulphate-modified cytochrome c increase after peroxynitrite or radiation treatment?

75%

Gebicka L. , Didik J.

Acta Biochimica Polonica

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2005

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tom 52

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nr 2

EN

The peroxidase-like activity of cytochrome c is considerably increased by unfolding of the protein. The enhancement of the activity is due to the higher reaction rate of unfolded cytochrome c with hydrogen peroxide, which is the rate-determining step in the peroxidase cycle of cytochrome c (Gębicka, L., 2001, Res Chem Intermed 27, 717–23). In this study we checked whether combined action of two unfolding factors, SDS and peroxynitrite or radiation (hydroxyl radicals), increases the peroxidase-like activity of cytochrome c more than any single treatment alone. Peroxynitrite reacts with SDS-modified cytochrome c in the same way as with native cytochrome c, via intermediate radical products, •OH/•NO2, arising from peroxynitrite homolysis. We found that SDS-modified cytochrome c is much more sensitive to oxidative damage than the native protein. Partial unfolding of cytochrome c by SDS causes the peroxide substrate to have a better access to the heme center. On the other hand, the amino acids located in the vicinity of the active site and/or heme group become accessible for oxidizing radicals. The overall effect observed is that the peroxidase-like activity of SDS-modified cytochrome c decreases with an increase of the concentration of the oxidizing species (peroxynitrite or radiolytically generated hydroxyl radicals). The damage of SDS-modified cytochrome c caused by irradiation is much more significant than that observed after peroxynitrite treatment.

6

Water evacuation from pea seeds previously treated with HgCl2 and surfactants (SDS, Triton X-100)

63%

Poliszko S. , Plenzler G. , Klimek-Poliszko D. , Napierala D.

Electronic Journal of Polish Agricultural Universities. Series Agronomy

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2008

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tom 11

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nr 2

7

Several dystrophin-glycoprotein complex members are present in crude surface membranes but they are sodium dodecyl sulphate invisible in KCI-washed microsomes from mdx mouse muscle

63%

Daval S. , Rocher C. , Cherel Y. , Rumeur E.

Cellular and Molecular Biology Letters

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2010

|

tom 15

|

nr 1

134-152

EN

The dystrophin-glycoprotein complex (DGC) is a large trans-sarcolemmal complex that provides a linkage between the subsarcolemmal cytoskeleton and the extracellular matrix. In skeletal muscle, it consists of the dystroglycan, sarcoglycan and cytoplasmic complexes, with dystrophin forming the core protein. The DGC has been described as being absent or greatly reduced in dystrophin-deficient muscles, and this lack is considered to be involved in the dystrophic phenotype. Such a decrease in the DGC content was observed in dystrophin-deficient muscle from humans with muscular dystrophy and in mice with X-linked muscular dystrophy (mdx mice). These deficits were observed in total muscle homogenates and in partially membrane-purified muscle fractions, the so-called KCl-washed microsomes. Here, we report that most of the proteins of the DGC are actually present at normal levels in the mdx mouse muscle plasma membrane. The proteins are detected in dystrophic animal muscles when the immunoblot assay is performed with crude surface membrane fractions instead of the usually employed KCl-washed microsomes. We propose that these proteins form SDS-insoluble membrane complexes when dystrophin is absent.

8

Determination of protein in human serum by resonance light scattering method using methylene blue

63%

Liu B. , Lu L. , Wang M. , Zhang Y. , Huang Y. , Zi Y.

Chemia Analityczna

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2009

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tom Vol. 54, No. 5

975-987

EN

Binding reaction of methylene blue (MB) with human serum albumin (USA) in the presence of sodium dodecyl sulfate (SDS) was studied. It was found that at pH = 2.87 positively charged MB bound firstly to HSA via hydrogen and hydrophobic bonds to form MB—HSA aggregate. The aggregate contained many positive charges and attracted negatively charged SDS to form macromolecules, which induced a great enhancement of RLS intensity. RLS intensity was directly proportional to the concentration of HSA. This phenomenon was utilised in a new method for quantitative determination of HSA protein.

PL

Badano reakcję wiązania błękitu metylenowego (MB) z albuminą osocza (HSA) w obecności dodecylo-siarczanu sodu (SDS). Stwierdzono, że przy kwasowości środowiska pH 2,87 dodatnio naładowany MB może początkowo wiązać HSA przez wiązanie wodorowe i wiązanie hydrofobowe tworząc MB-HSA, który zawiera wiele dodatnich ładunków i może reagować z ujemnie naładowanymi jonami SDS. W wyniku tego następuje podwyższenie natężenia rezonansowego rozproszenia światła, które jest proporcjonalne do stężenia HSA. Na tej podstawie opracowano nową metodę ilościowego oznaczania białka.

9

Biodegradation of sodium dodecyl sulphate (SDS) by activated sludge in the flow system

63%

Liwarska-Bizukojc E. , Bizukojc M.

Archiwum Ochrony Środowiska

|

2006

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tom Vol. 32, no. 1

33-42

EN

Surfactants can interfere with the biological wastewater treatment processes. They contribute to the changes in activated sludge floes structure. In order to quantify the influence of surfactants on sludge floes morphology the series of experiments in the flow continuous system were conducted. Sodium dodecyl sulphate, which belongs to the most ubiquitous anionic surfactant in everyday use, was selected to be the object of investigations. The results of its biodegradation in continuous flow system at influent concentration of 250 mg -dm° are presented. It turned out that SDS diminished the mean projected area of floes from 50 000 to 15 000 urn2 with the increase of dilution rate from 0.029 to 0.192 h1. At the same time the o tamed data confirmed that there was a correlation between the morphological parameters of floes and other biomass indicators. The linear relation between mean projected area of floes and volatile suspended solids was found.

PL

Syntetyczne substancje powierzchniowo czynne mogą oddziaływać na biologiczne oczyszczanie ścieków. Przyczyniają się one między innymi do zmian w strukturze kłaczków osadu czynnego. Celem niniejszej pracy było określenie wpływu dodecylosiarczanu sodu (SDS), zaliczanego do anionowych substancji powierzchniowo czynnych, na morfologię kłaczków osadu czynnego. Badania zostały przeprowadzone w skali laboratoryjnej w układzie ciągłym dla czterech różnych szybkości rozcieńczania. Stężenie SDS w dopływających ściekach było stałe i wynosiło 250 mg dm3. Okazało się, że wraz ze zwiększaniem szybkości rozcieńczania od 0,029 do 0,192 h1 średnie pole powierzchni rzutu kłaczka zmniejszyło się z 50 000 do 15 000 nm2. Uzyskane wyniki wskazują, że istnieje korelacja między parametrami morfologicznymi kłaczków a innymi indykatorami biomasy. Stwierdzono liniową zależność pomiędzy średnim polem powierzchni rzutu kłaczków a zawiesiną organiczną.

10

Biochemical characterization of surface antigens of infective larvae and adults of Haemonchus contortus

63%

Schallig H. D. F. H. , Baczkowska A. M. , Wedrychowicz H.

Acta Parasitologica

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1995

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tom 40

|

nr 4

EN

Surface proteins of the nematode Haemonchus contortus were biochemically characterized and their antigenic properties were investigated. Living parasites were labelled with NHS-biotin. Next, extracts were made using cetyltrimethylammonium bromide (СТАВ), Tris buffered saline (TBS), sodium dodecyl sulphate (SDS) and 2-mercaptoethanol (BME) as solubilizing agents. The presence of glycoproteins in the extracts was examined by probing Western blots with the lectin Concanavalin A (Con A). The antigenic character of the surface proteins was studied by immunoblotting. Glycosylated polypeptides constituted the major part of the surface molecules of larvae, whereas the proportion of glycoproteins in adults is relatively smaller. Surface biotinylation of intact nematodes revealed that СТАВ-, TBS- and SDS-soluble proteins belong to the epicuticle of larvae. СТАВ- and TBS-soluble proteins are present in the surface of adult worms. Many surface proteins of H. contortus were recognized by hyperimmune sera. It was found that the majority of these antigens possess carbohydrate epitopes. However, antigens with nonsugar epitopes are also present in the epicuticle.

11

Influence of acetaminophen and trichloroethylene on liver cytochrome P450-dependent monooxygenase system

63%

Plewka A. , Zielinska-Psuja B. , Kowalowka-Zawieja J. , Nowaczyk-Dura G. , Plewka D. , Wiaderkiewicz A. , Kaminski M. , Orlowski J.

Acta Biochimica Polonica

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2000

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tom 47

|

nr 4

EN

The aim of the study was to evaluate the effect of acetaminophen (APAP) and/or trichloroethylene (TRI) on the liver cytochrome P450-dependent monooxygenase system, CYP2E1 and CYP1A2 (two important P450 isoforms), and liver glutathione (GSH) content in rats. Rats were given three different doses of APAP (250, 500 and 1000 mg/kg b...) and then the above-mentioned parameters were measured for 48 h. The lowest APAP dose produced small changes in the cytochrome P450 content of liver. At 500 mg/kg APAP increased the cytochrome P450 content to 230% of the control. The inductive effect was seen at 1000 mg/kg dose but at 24 h and later. NADPH-cytochrome P450 reductase activity was the highest after the lowest dose of APAP, while after the highest dose it was equal to the control value. TRI increased both the cytochrome P450 content and the NADPH-cytochrome P450 reductase activity. When TRI was combined with APAP, both these parameters increased in the first hours of observation, but they returned to the control values at 24 h. When APAP was given at 250 mg/kg, GSH levels decreased to 55% of the control at 8 h and returned to the control values at 24 h. The higher doses of APAP decreased GSH levels more than the lowest dose, but after 24 h GSH levels did not differ from those of the control. When TRI was given at 250 mg/kg, the GSH levels decreased to 68% of the control at 2 h and then they increased gradually and tended to exceed the control values at 48 h. The effect of TRI combined with APAP on the level of GSH was virtually the same as that of APAP alone given at 500 mg/kg.

12

Arabidopsis thaliana Nudix hydrolase AtNUDT7 forms complexes with the regulatory RACK1A protein and gamma subunits of the signal transducing heterotrimeric G protein

51%

Olejnik K. , Bucholc M. , Anielska-Mazur A. , Lipko A. , Kujawa M. , Modzelan M. , Augustyn A. , Kraszewska E.

Acta Biochimica Polonica

|

2011

|

tom 58

|

nr 4

EN

Arabidopsis thaliana AtNUDT7 Nudix pyrophosphatase hydrolyzes NADH and ADP-ribose in vitro and is an important factor in the cellular response to diverse biotic and abiotic stresses. Several studies have shown that loss-of-function Atnudt7 mutant plants display many profound phenotypes. However the molecular mechanism of AtNUDT7 function remains elusive. To gain a better understanding of this hydrolase cellular role, proteins interacting with AtNUDT7 were identified. Using AtNUDT7 as a bait in an in vitro binding assay of proteins derived from cultured Arabidopsis cell extracts we identified the regulatory protein RACK1A as an AtNUDT7-interactor. RACK1A-AtNUDT7 interaction was confirmed in a yeast two-hybrid assay and in a pull-down assay and in Bimolecular Fluorescence Complementation (BiFC) analysis of the proteins transiently expressed in Arabidopsis protoplasts. However, no influence of RACK1A on AtNUDT7 hydrolase catalytic activity was observed. In vitro interaction between RACK1A and the AGG1 and AGG2 gamma subunits of the signal transducing heterotrimeric G protein was also detected and confirmed in BiFC assays. Moreover, association between AtNUDT7 and both AGG1 and AGG2 subunits was observed in Arabidopsis protoplasts, although binding of these proteins could not be detected in vitro. Based on the observed interactions we conclude that the AtNUDT7 Nudix hydrolase forms complexes in vitro and in vivo with regulatory proteins involved in signal transduction. Moreover, we provide the initial evidence that both signal transducing gamma subunits bind the regulatory RACK1A protein.

13

Effect of NaCl and temperature on sodium dodecyl sulfate mixed micells

51%

Kokot Z.

Chemia Analityczna

|

2001

|

tom Vol. 46, No. 6

823-829

EN

The size and shape of sodium dodecyl sulfate (SDS) micelles containing the solubilized normal alcohols, fatty acids, and fatty acid methyl esters were investigated using laser light scattering spectroscopy. In the presence of NaCl (0.4-0.6 mol 1(-1) the mean hydrodynamic radius Rh) of the mixed micelles strongly increased in function of the solute concentration. Rh also increased upon addition of NaCl and decreased with increasing temperature. As the number of the carbon atoms in the solute hydrocarbon chain was increased from 6 to 16, Rh increased to a maximum at ten carbon atoms, and then decreased. With the compounds studied, the micellar size change was essentially independent of the nature of the solute added. The solute chain length dependence of Rh was thought to be caused by the combination of stabilizing effects of hydrophobic and van der Waals forces and steric destabilization of the cylindrical structure as the length of the solute chain became similar to that of SDS.

PL

Badano wielkość i kształt micel soli sodowej siarczanu dodecylowego (SDS) zawierających rozpuszczone n-alkohole, kwasy tłuszczowe i estry metylowe tych kwasów, wykorzystując spektrometrię laserowego światła rozproszonego. średni promień hydrodynamiczny Rh) micel mieszanych SDS w obecności NaCl (0.4-0.6 mol 1'1) wzrastał wraz ze wzrostem stężenia wymienionych wyżej związków; Rh wzrastał również ze wzrostem stężenia NaCl oraz malał ze wzrostem temperatury. Badane związki zawierały od 6 do 16 atomów węgla w cząsteczce. Wraz ze wzrostem liczby atomów węgla w cząsteczce następował wzrost wielkości micel osiągając maksimum przy długości łańcucha równym 10 atomów węgla w cząsteczce a następnie wielkość micel zmniejszała się. Zmiana wielkości micel mieszanych była praktycznie niezależna od charakteru chemicznego związku - alkoholu, kwasu czy estru a jedynie w istotny sposób zależała od długości łańcucha związku rozpuszczonego.

14

Integrin receptors play a role in the internalin B-dependent entry of Listeria monocytogenes into host cells

51%

Auriemma C. , Viscardi M. , Tafuri S. , Pavone L. M. , Capuano F. , Rinaldi L. , Della Morte R. , Iovane G. , Staiano N.

Cellular and Molecular Biology Letters

|

2010

|

tom 15

|

nr 3

496-506

EN

Listeria monocytogenes enters non-phagocytic cells by binding its surface proteins inlA (internalin) and inlB to the host’s E-cadherin and Met, respectively. The two internalins play either separate or cooperative roles in the colonization of infected tissues. Here, we studied bacterial uptake into HeLa cells using an L. monocytogenes mutant strain (ΔinlA) carrying a deletion in the gene coding for inlA. The ΔinlA mutant strain showed the capability to invade HeLa cells. The monoclonal anti-β3- and anti-β1-integrin subunit antibodies prevented bacterial uptake into the cells, while the anti-β2- and anti-β4-integrin subunit antibodies failed to affect L. monocytogenes entry into HeLa cells. Three structurally distinct disintegrins (kistrin, echistatin and flavoridin) also inhibited bacterial uptake, showing different potencies correlated to their selective affinity for the β3- and β1-integrin subunits. In addition to inducing Met phosphorylation, infection of cells by the L. monocytogenes ΔinlA mutant strain promoted the tyrosine phosphorylation of the focal adhesion-associated proteins FAK and paxillin. Our findings provide the first evidence that β3- and β1-integrin receptors play a role in the inlB-dependent internalization of L. monocytogenes into host cells.

15

Biodegradation of sodium dodecyl sulphate [SDS] by activated sludge in the flow system

51%

Liwarska-Bizukojc E. , Bizukojc M.

Archiwum Ochrony Środowiska

|

2006

|

tom 32

|

nr 1

16

Fluorescence quenching studies of pyrene in SDS micelle solutions

51%

Kaszycki P. , Wasylewski Z.

Current Topics in Biophysics

|

1993

|

tom 17

|

nr 1-2

17

The stimulation and inhibition of T cell proliferation by Helicobacter pylori components

44%

Chmiela M. , Lelwala-Guruge J. A. , Wadstrom T. , Rudnicka W.

Journal of Physiology and Pharmacology

|

1996

|

tom 47

|

nr 1