Wyniki wyszukiwania - Biblioteka Nauki

1

Genomics and the evolution of aminoacyl-tRNA synthesis.

100%

Ruan B. , Ahel I. , Ambrogelly A. , Becker H. D. , Bunjun S. , Feng L. , Tumbula-Hansen D. , Ibba M. , Korencic D. , Kobayashi H. , Jacquin-Becker C. , Mejlhede N. , Min B. , Raczniak G. , Rinehart J. , Stathopoulos C. , Li T. , Söll D.

Acta Biochimica Polonica

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2001

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tom 48

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nr 2

313-321

EN

Translation is the process by which ribosomes direct protein synthesis using the genetic information contained in messenger RNA (mRNA). Transfer RNAs (tRNAs) are charged with an amino acid and brought to the ribosome, where they are paired with the corresponding trinucleotide codon in mRNA. The amino acid is attached to the nascent polypeptide and the ribosome moves on to the next codon. Thus, the sequential pairing of codons in mRNA with tRNA anticodons determines the order of amino acids in a protein. It is therefore imperative for accurate translation that tRNAs are only coupled to amino acids corresponding to the RNA anticodon. This is mostly, but not exclusively, achieved by the direct attachment of the appropriate amino acid to the 3'-end of the corresponding tRNA by the aminoacyl-tRNA synthetases. To ensure the accurate translation of genetic information, the aminoacyl-tRNA synthetases must display an extremely high level of substrate specificity. Despite this highly conserved function, recent studies arising from the analysis of whole genomes have shown a significant degree of evolutionary diversity in aminoacyl-tRNA synthesis. For example, non-canonical routes have been identified for the synthesis of Asn-tRNA, Cys-tRNA, Gln-tRNA and Lys-tRNA. Characterization of non-canonical aminoacyl-tRNA synthesis has revealed an unexpected level of evolutionary divergence and has also provided new insights into the possible precursors of contemporary aminoacyl-tRNA synthetases.

2

Effect of cycloheximide on some physiological changes associated with senescence of detached flowers of Iris germanica L.

100%

Sultan S. M. , Farooq S.

Acta Physiologiae Plantarum

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1997

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tom 19

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nr 1

EN

Silverthiosulphate which is a potent inhibitor of ethylene action was found to be ineffective in delaying senescence of detached flowers of Iris germanica whereas cycloheximide, a protein synthesis inhibitor, effectively delayed the senescence of these flowers and extended the longevity to 6 days. However, this treatment resulted in suppression of bud opening. When cycloheximide treatment was given at progressive intervals it became less effective in inhibiting bud opening and delaying senescence. Cycloheximide treatment maintained a higher protein content in the perianth tissue of flowers compared to untreated flowers.

3

Brain protein synthesis in rats with portacaval shunts

100%

Helewski K. , Konecki J.

Journal of Physiology and Pharmacology

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1994

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tom 45

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nr 4

4

Role of sulfation in the processing of gastric mucins

86%

Liau Y. H. , Murty V. L. N. , Slomiany A. , Bielanski W. , Slomiany B. L.

Journal of Physiology and Pharmacology

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1991

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tom 42

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nr 4

EN

The role of sulfation in the processing of mucus glycoprotein in gastric mucosa was investigated. Rat gastric mucosal segments were incubated in MEM at various medium sulfate concentrations in the presence of [³⁵S]Na₂ SO₄ [³H] glucosamine and [³H]proline, with and without chlorate an inhibitor of PAPS formation. The results revealed that the mucin sulfation attained maximum at 300 µM medium sulfate concentration. Introduction of chlorate into the incubation medium, while having no effect on the protein synthesis as evidenced by [³H]proline incorporation, caused at its optimal concentration of 2 mM a 90% decrease in mucin sulfation and a 40% drop in mucin glycosylation. Evaluation of mucin molecular forms distribution indicated the predominance of the high molecular mucin form in the interacellular fraction and the low molecular mucin from in the extracellular fraction. Increase in medium sulfate caused an increase in the high molecular weight mucin form in both fractions, and this effect was inhibited by chlorate. Also, higher medium sulfate concentrations led to a higher degree of sulfation in the high molecular weight mucin form, the effect of which was inhibited by chlorate. The results suggest that the sulfation process is an early event taking place at the stage of mucin subunit assembly and is required for mucin polymer formation. Hence, the disturbances in mucin sulfation process could be determinal to the maintenance of gastric mucus coat integrity.

5

Metody otrzymywania nienaturalnych aminoacylo-tRNA

86%

Plitta B. , Giel-Pietraszuk M. , Barciszewski J.

Wiadomości Chemiczne

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2007

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tom [Z] 61, 1-2

61-77

EN

Despite an enormous progress in the development of biophysical methods to establish protein structure and function, there is still a lack of precise ways of detection and mapping the specific fragments of molecules, in terms of their structure and properties. This is due to the fact that only a few amino acids show specific properties - like fluorescence of tryptophan - which enable analysis of the interaction and formation mechanism of protein - nucleic acids complexes. These problems one can easily overcome using proteins containing non-natural amino acid. However, all methods used in in vitro protein synthesis require up till now aminoacyl-tRNA as a substrate. Hence, the acylation of tRNA is a key and limiting step of every method. In the present article, we show all known non-enzymatical methods of tRNA acylation. One of them is based on ribozymes obtained by in vitro evolution (SELEX). These ribozymes that transfer amino acid bound to its 5'-end to 3'-end of tRNA can specifically recognize amino acid or tRNA. Other attempts aimed at chemical synthesis of aminoacyl-nucleotides, which were further ligated to appropriately prepared tRNA. As an amino acid donor, the peptidylnucleic acid (PNA) was used as well. An alternative method is an acylation under high hydrostatic pressure which allows to attach any amino acid to tRNA in a one-step procedure. All mentioned methods can be used in protein translation in vitro. For in vivo synthesis of protein containing non-natural amino acid, orthogonal pairs of tRNA-AARS are used. In orthogonal pairs mutated aminoacyl-tRNA synthetase recognizes specific amino acid and acylates suppressor amber tRNA.

6

Day-to-night activity of bacteria in the surface microlayer eutrophic lake

86%

Walczak M.

Polish Journal of Ecology

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2008

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tom 56

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nr 3

379-389

EN

This study examined changes of bacteria numbers in the surface microlayer (SM) and subsurface water (SW) of a lake during a day- and night-time. The research also addresses the synthesis of DNA and cell protein as well as the activity of cellular dehydrogenases depending on time of the day. Results demonstrated that in spring and summer the numbers of bacteria (per cm3 ) in the SM was significantly greater during night-time than day-time (average: May, daytime – 30.058 × 10⁶, night-time – 71.343 × 10⁶; July, day-time – 10.801 × 10⁶, night-time – 40.353 × 10⁶). In October, numbers of bacteria in dayand night-time were not statistically different (respectively: 5.841 × 10⁶ and 3.664 × 10⁶). Results indicated also that the rate of DNA synthesis by SM bacteria was much higher in the night-time (average: May – 2.049 × 10⁻⁶ pg h⁻¹ cell⁻¹; July – 1.363 × 10⁻⁶ pg h⁻¹ cell⁻¹), than in the day-time (average: May – 0.7263 × 10⁻⁶ pg h⁻¹ cell⁻¹; July – 0.3404 ×10⁻⁶ pg h⁻¹ cell⁻¹). In contrast, in October the values of DNA synthesis by SM bacteria were higher in night-time. These changes are significantly smaller in SW at a depth of several dozen centimetres. However, no significant impact was observed of a time of the day on the activity of protein synthesis and activity of cellular dehydrogenases by bacteria inhabiting SM and SW.

7

Influence of low temperature on the synthesis of some Galleria mellonella proteins

86%

Kludkiewicz B. , Godlewski J. , Grzelak K. , Cymborowski B. , Lassota Z.

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tom 43

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nr 4

EN

In developing Gallería mellonella larvae (reared at 30°C) three proteins of 74/ 76 and 81/82 kDa were identified. They represent a group of storage proteins (LHP proteins). In Galleria larvae, the development of which is arrested by low temperature (18°C)/ accumulation of the 74, 76 and 81/82 kDa proteins was detected in the hemolymph. The synthesis of 74 kDa and 76 kDa proteins started after 24 h, and that of about 80 kDa after 96 h following the transfer of larvae from 30°C to 18°C. 20-Hydroxyecdysone inhibited synthesis of the 74 and 76 kDa proteins in larvae exposed to low temperature. The arrest of development of Galleria larvae is associated with the synthesis and accumulation of storage proteins, and ecdysteroids are involved in these processes.

8

From accuracy in protein synthesis to cardiovascular disease: The role of homocysteine

86%

Jakubowski H.

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nr 3

9

RNA localization and its role in the spatially restricted protein synthesis

86%

Kloc M. , Bilinski S. M.

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2003

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tom 41

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nr 1

10

The small heat shock proteins: an ancient response to temperature stress

86%

Lee G. J. , Basha E. , Suzuki T. , Waters E. R. , Wehmeyer N. , Vierling E.

Biological Bulletin of Poznań. Supplement

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1997

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tom 34

11

Immunolocalization and in vitro cryoprotective activity of PCA60: a peach dehydrin

86%

Wisniewski M.

Biological Bulletin of Poznań. Supplement

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1997

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tom 34

12

Polysomes in lupin roots exposed to heat shock

86%

Porankiewicz J. , Gwozdz E. A.

Acta Physiologiae Plantarum

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1995

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tom 17

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nr 1

13

Protein synthesis in lupin roots exposed to heat shock

86%

Porankiewicz J. , Gwozdz E. A.

Acta Physiologiae Plantarum

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1995

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tom 17

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nr 1

14

Teratogenic effects of chlormethine hydrochloride in rats

86%

Anasiewicz A.

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nr 4

15

Adrenal hormones and the regulation of acute phase protein synthesis

86%

Boers W. , Smit R. A. , Sala M. , Maas A. , Chamuleau R. A. F. M.

Folia Histochemica et Cytobiologica

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1992

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tom 30

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nr 4

16

A common oxygen sensor regulates the sensory discharge and glomus cell HIF-1alpha in the rat carotid body

72%

Lahiri S. , Antosiewicz J. , Pokorski M.

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2007

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tom 58

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nr 5

17

Role of RNA backbone groups for ribosomal catalysis

72%

Erlacher M. D. , Polacek N.

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nr 1

65-80

18

Podstawy informatycznych technologii bezpośredniego wytwarzania produktów

72%

Węgrzyn S.

Zeszyty Naukowe Wydziału ETI Politechniki Gdańskiej. Technologie Informacyjne

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2007

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tom T. 12

133-144

PL

Zadaniem projektowanych i budowanych obecnie technicznych systemów informatyki jest automatyczna realizacja procesów obliczeniowych. W przedstawionym opracowaniu podana jest analiza warunków, które powinny by spełniać techniczne systemy informatyki, aby mogły realizować procesy bezpośredniego wytwarzania materiałów, na przykład białek, tak jak to ma miejsce w systemach informatyki istniejących w organizmach biologicznych. Przedstawia się więc kolejne etapy zachodzącego w organizmach biologicznych procesu syntezy białek i omawia warunki które trzeba by stworzyć aby mogły być realizowane metodami technicznymi poza organizmami.

EN

The objective of the currently designed and produced technical informatics systems is the automated implementation of computational processes. In the presented work we analyze the condition that technical informatics sys-tems should meet so that they can implement the direct material production. One such an example is protein production in the informatics system of organisms. Therefore we present successive steps of protein synthesis in biological organisms, and then we discuss the conditions that most be satisfied in order to be implemented by technical methods outside organisms.

19

Acetylsalicylic acid inhibits collagen biosynthesis in cultured fibroblasts

72%

Galewska Z. , Palka J. , Bankowski E.

Bulletin of the Polish Academy of Sciences. Biological Sciences

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1990

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tom 38

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nr 1-12

20

UVB Radiation Impact on Activity of DNA and Cellular Protein Synthesis of Water Environment Bacteria

72%

Walczak M. , Burkowska A.

Ecological Chemistry and Engineering. A

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2011

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tom Vol. 18, nr 3

469-475

EN

The studies were carried out in 2007 based on water samples collected from SM and SW of pelagic zone of Brzezno lake. For the purpose of further research, representative collection of bacterial strains was isolated from collected samples. The progress of the research included estimation of the DNA and cellular protein synthesis activity of the bacteria subjected to UVB radiation. The survey was conducted in two experimental layouts: with and without humic substances (HS) playing role of compounds potentially protective from UV radiation. Conducted research demonstrated that under influence of UVB radiation the SM and SW bacteria activity of DNA and cellular protein synthesis were strongly inhibited. On the other hand, presence of HS have another impact on DNA and cellular protein synthesis.

PL

Badania prowadzono w 2007 r., pobierając próbki wody z MP i WPP w strefie pelagialu jeziora Brzeźno. Z pobranych próbkach wody izolowano reprezentatywną kolekcję szczepów, na których wykonywano dalsze badania. W toku badań oznaczano aktywność syntezy DNA i białek komórkowych bakterii poddanych promieniowaniu UVB. Badania prowadzono w dwóch układach doświadczalnych: bez substancji humusowych (SH) i w obecności tych substancji jako związków o działaniu potencjalnie ochronnych przed UV. Przeprowadzone badania wykazały, że pod wpływem promieniowania UVB aktywność syntezy DNA i białek komórkowych ulegały silnej inhibicji. Natomiast obecność SH inaczej wpływa na syntezę DNA i białek.