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1
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Potencjał elektrokinetyczny osadów sztucznego zbiornika wodnego – Zalewu Zemborzyckiego

100%
Ciesla J.
Acta Agrophysica
|
2008
|
tom 12
|
nr 3[163]
2

Energooszcędna instalacja chłodnicza. Czy warto wydać więcej, żeby płacić mniej?

100%
Ciesla J.
Magazyn Przemysłu Mięsnego
|
2010
|
nr 11-12
3

Metabolic enzymes that bind RNA: yet another level of cellular regulatory network?

100%
Ciesla J.
Acta Biochimica Polonica
|
2006
|
tom 53
|
nr 1
Several enzymes that were originally characterized to have one defined function in intermediatory metabolism are now shown to participate in a number of other cellular processes. Multifunctional proteins may be crucial for building of the highly complex networks that maintain the function and structure in the eukaryotic cell possessing a relatively low number of protein-encoding genes. One facet of this phenomenon, on which I will focus in this review, is the interaction of metabolic enzymes with RNA. The list of such enzymes known to be associated with RNA is constantly expanding, but the most intriguing question remains unanswered: are the metabolic enzyme-RNA interactions relevant in the regulation of cell metabolism? It has been proposed that metabolic RNA-binding enzymes participate in general regulatory circuits linking a metabolic function to a regulatory mechanism, similar to the situation of the metabolic enzyme aconitase, which also functions as iron-responsive RNA-binding regulatory element. However, some authors have cautioned that some of such enzymes may merely represent "molecular fossils" of the transition from an RNA to a protein world and that the RNA-binding properties may not have a functional significance. Here I will describe enzymes that have been shown to interact with RNA (in several cases a newly discovered RNA-binding protein has been identified as a well-known metabolic enzyme) and particularly point out those whose ability to interact with RNA seems to have a proven physiological significance. I will also try to depict the molecular switch between an enzyme's metabolic and regulatory functions in cases where such a mechanism has been elucidated. For most of these enzymes relations between their enzymatic functions and RNA metabolism are unclear or seem not to exist. All these enzymes are ancient, as judged by their wide distribution, and participate in fundamental biochemical pathways.
4

Baza danych melioracyjnych

63%
Ciesla J., Majchrowska E.
Zeszyty Naukowe Akademii Rolniczej w Krakowie. Sesja Naukowa
|
1991
|
tom 28.2
5
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Influence of silver nanoparticles on food components in wheat

63%
Nawrocka A., Ciesla J.
International Agrophysics
|
2013
|
tom 27
|
nr 1
During storage, grain might be affected by bacterial and fungal infections. Pathogens diminish the grain quality through contamination with excrements and second metabolites. It is very important to prevent grain from infections. Due to their antimicrobial properties, silver nanoparticles can play the role of an effective protector. The influence of nanoparticles on wheat quality was studied. The gluten parameters and falling number did not change after covering the grain with silver nanoparticles stabilized by sodium citrate. Changes in the structure of starch and gluten were investigated using Fourier-transform infrared spectroscopy. Infrared spectra of the whole meal and starch have shown a slight shift (from 1 000 to 995cm-1) of the band connected with the C–O–H bending. This displacement is probably related to the changes in sample moisture. Significant differences, corresponding to changes in the protein secondary structure, have appeared in the gluten spectra after covering.Adecrease of absorbance in the amide and CH and OHregions has been observed regardless of the covering time.
6

Themidylate synthase activity in the development of Hymenolepis diminuta

51%
Ciesla J., Zielinski Z., Machnicka B., Rode W.
Acta Biochimica Polonica
|
1987
|
tom 34
|
nr 3
7

Sensory chemiczne i biosensory w kontroli zywnosci zmodyfikowanej genetycznie

51%
Radecki J., Radecka H., Ciesla J., Tudek B.
Biotechnologia
|
2006
|
nr 3
67-78
8

Phosphorylation of basic amino acid residues in proteins: important but easily missed

51%
Ciesla J., Fraczyk T., Rode W.
Acta Biochimica Polonica
|
2011
|
tom 58
|
nr 2
Reversible phosphorylation is the most widespread posttranslational protein modification, playing regulatory role in almost every aspect of cell life. The majority of protein phosphorylation research has been focused on serine, threonine and tyrosine that form acid-stable phosphomonoesters. However, protein histidine, arginine and lysine residues also may undergo phosphorylation to yield acid-labile phosphoramidates, most often remaining undetected in conventional studies of protein phosphorylation. It has become increasingly evident that acid-labile protein phosphorylations play important roles in signal transduction and other regulatory processes. Beside acting as high-energy intermediates in the transfer of the phosphoryl group from donor to acceptor molecules, phosphohistidines have been found so far in histone H4, heterotrimeric G proteins, ion channel KCa3.1, annexin 1, P-selectin and myelin basic protein, as well as in recombinant thymidylate synthase expressed in bacterial cells. Phosphoarginines occur in histone H3, myelin basic protein and capsidic protein VP12 of granulosis virus, whereas phospholysine in histone H1. This overview of the current knowledge on phosphorylation of protein basic amino-acid residues takes into consideration its proved or possible roles in cell functioning. Specific requirements of studies on acid-labile protein phosphorylation are also indicated.
9
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The effect of Haplic Phaeozem and Leptic Podzol properties on sorption of lead and cadmium in soil

51%
Kosynets O., Nosalewicz A., Ciesla J.
Acta Agrophysica
|
2007
|
tom 10
|
nr 1[151]
10

Pieniądze na biznes - premie na rozpoczęcie działalności pozarolniczej

50%
Ciesla J.
Poradnik Gospodarski
|
2019
|
nr 10
11

Zasolenie gleby wyznaczane sensorami FDR działającymi w zmiennej częstotliwości

45%
Wilczek A., Skierucha W., Janik G., Ciesla J., Pichler V.
Woda - Środowisko - Obszary Wiejskie
|
2012
|
tom 12
|
nr 2[38]
12
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Porownanie wlasciwosci syntazy tymidylanowej oczyszczonej z tasiemca szczurzego, Hymenolepis diminuta, z wlasciwosciami enzymu zywiciela wyizolowanego z regenerujacej watraby szczura

45%
Ciesla J., Machnicka B., Pawelczak K., Rzeszotarska B., Rode W.
Wiadomości Parazytologiczne
|
1992
|
tom 38
|
nr 1-2
23-29
Thymidylate synthases (TS) from the tapeworm, Hymenolepis diminuta, and regenerating rat liver have been purified by means of affinity chromatography on immobilized 10-formyl-5,8-dideazafolate and concentrated on immobilized p-aminophenyl-5-fluoro-2'-deoxyuridine monophosphate. Molecular weights of native TS from the tapeworm and regenerating rat liver were 62 kD and 81.5 kD, respectively, and molecular weights of the monomers were 34.4 kD and 34.9 kD, respectively, painting to dimeric structures of both enzymes. The dependence of TS activity on temperature (ARRHENIUS plot) was biphasic for the parasite enzyme, with lower activation energy above 32°C, and monophasic for the host enzyme. 2'-deoxyuridine-5'-monophosphate (dUMP) analogues, 5-fluoro-2'-deoxyuridine-5' -monophosphate (5-FdUMP), 2-tio-5-FdUMP, N⁴-hydroxy-2'-deoxycytidine-5'-monophosphate (N⁴-hydroxy-dCMP) and N⁴-hydroxy-5-FdCMP, were competitive with respect to dUMP, slow-binding inhibitors of TS from both sources, with K₁ values in 10⁻⁶ - 10⁻⁹ M range. 5-FdUMP was distinctly stronger inhibitor of the host than the tapeworm TS, whereas N⁴-hydroksy-5-FdCMP inhibited stronger the parasite enzyme. Interactions of 5,10-methylenetetrahydrofolate (CH₂H₄PteGlu) analogue, 10-propargyl-5,8-dideazafolate (pddPteGlu), and its di- and triglutamates with both enzymes were studied. Inhibition of the parasite and host enzymes by pddPteGlu was of mixed-type with respect to CH₂H₄PteGlu, with K₁ values in 10⁻⁸ M range. Introduction of additional glutamate residues changed inhibition type to noncompetitive with respect to CH₂H₄PteGlu and lowered K₁ values (pddPteGlu₃ < pddPteGlu₂ < pddPteGlu₁). The latter potentiation of inhibitory properties was distinctly stronger in case of the tapeworm than regenerating rat liver TS.
13

Altered mouse leukemia L1210 thymidylate synthase, associated with cell resistance to 5-fluoro-dUrd, is not mutated but rather reflects posttranslational modification

45%
Ciesla J., Fraczyk T., Zielinski Z., Sikora J., Rode W.
Acta Biochimica Polonica
|
2006
|
tom 53
|
nr 1
Thymidylate synthase purified from 5-fluoro-dUrd-resistant mouse leukemia L1210 cells (TSr) was less sensitive to slow-binding inhibition by 5-fluoro-dUMP than the enzyme from the parental cells (TSp), both enzyme forms differing also in sensitivity to several other dump analogues, apparent molecular weights of monomer and dimer, and temperature dependence of the catalyzed reaction. Direct sequencing of products obtained from RT-PCR, performed on total RNA isolated from the parental and 5-fluoro-dUrd-resistant cells, proved both nucleotide sequences to be identical to the mouse thymidylate synthase coding sequence published earlier (NCBI protein database access no. NP_067263). This suggests that the altered properties of TSr are caused by a factor different than protein mutation, presumably posttranslational modification. As a possibility of rat thymidylate synthase phosphorylation has been recently demonstrated (Samsonoff et al. (1997) J Biol Chem 272: 13281), the mouse enzyme amino-acid sequence was analysed, revealing several potential phosphorylation sites. In order to test possible influence of the protein phosphorylation state on enzymatic properties, endogenous TSp and TSr were purified in the presence of inhibitors of phosphatases. Although both enzyme forms were phosphorylated, as shown by electrophoretical separation followed by phosphoprotein detection, the extent of phosphorylation was apparently similar. However, the same two purified enzyme preparations, compared to the corresponding preparations purified in the absence of phosphatase inhibitors, showed certain properties, including sensitivity to the slow-binding inhibition by FdUMP, altered. Thus properties dependence on phosphorylation was indicated.
14

Thymidylate biosynthesis as a target in chemotherapy. Potential importance of a peculiar expression pattern of enzymes involved in thymidylate biosynthesis in nematodes

39%
Rode W., Dabrowska M., Golos B., Winska P., Jagielska E., Ciesla J., Zielinski Z.
Acta Biochimica Polonica
|
2003
|
tom 50
|
nr Supplement 1
15

The effect of Arg209 to Lys mutation in mouse thymidylate synthase

39%
Ciesla J., Golos B., Walajtys-Rode E., Jagielska E., Plucienniczak A., Rode W.
Acta Biochimica Polonica
|
2002
|
tom 49
|
nr 3
Mouse thymidylate synthase R209K (a mutation corresponding to R218K in Lactobacillus casei), overexpressed in thymidylate synthase-deficient Escherichia coli strain, was poorly soluble and with only feeble enzyme activity. The mutated protein, incubated with FdUMP and N5,10-methylenetetrahydrofolate, did not form a complex stable under conditions of SDS/polyacrylamide gel electrophoresis. The reaction cata­lyzed by the R209K enzyme (studied in a crude extract), compared to that catalyzed by purified wild-type recombinant mouse thymidylate synthase, showed the Km value for dUMP 571-fold higher and Vmax value over 50-fold (assuming that the mutated en­zyme constituted 20% of total crude extract protein) lower. Thus the ratios kcat,R209K/kcat,'wild' and (kcat, R209K/Km, R209K dUMP)/ (kcat, 'wild'/Km, 'wild' dUMP) were 0.019 and 0.000032, respectively, documenting that mouse thymidylate synthase R209, similar to the corresponding L. casei R218, is essential for both dUMP binding and enzyme reaction.
16

Products of lipid peroxidation as mutagenic and carcinogenic mediators of inflammation

33%
Tudek B., Kowalczyk P., Ciesla J., Pokrywinska G., Rusin B., Zielinska M., Speina E., Kusmerek J.
Acta Biochimica Polonica
|
2003
|
tom 50
|
nr Supplement 1
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