Full-text resources of PSJD and other databases are now available in the new Library of Science.
Visit https://bibliotekanauki.pl
Preferences help
Polish version English version Language
enabled [disable] Abstract
Number of results

Results found: 8

Number of results on page
first rewind previous Page / 1 next fast forward last

Search results

help Sort By:

help Limit search:
first rewind previous Page / 1 next fast forward last
1
Content available remote

The determination of tryptophan and tyrosine in native proteins on the basis of inner filter effect in spectrofluorimetry

100%
Jankowski A., Siemion I. Z.
Acta Biochimica Polonica
|
1977
|
vol. 24
|
issue 1
13-20
2
Content available remote

The labelling of peptides and proteins with a new fluorophore: N-acetyl-DL-(p-N',N'-dimethylamino)phenylalanine

81%
Siemion I. Z., Stefanowicz P., Jankowski A.
|
|
issue 1
11-20
3
Content available remote

The determination of thymopoietin conformation based on X-ray structure of a discontinuous thymopoietin-like motif of G-actin

81%
Siemion I. Z., Strug I., Szewczuk Z.
Acta Biochimica Polonica
|
1997
|
vol. 44
|
issue 3
519-525
4
Content available remote

The influence of configurational changes in tuftsin peptide chain on its folding properties

81%
Sucharda-Sobczyk A., Siemion I. Z., Nawrocka E.
Acta Biochimica Polonica
|
1980
|
vol. 27
|
issue 3-4
353-363
5
Content available remote

_1H NMR spectra of trypsin inhibitors from seeds of Cucurbitaceae plants. Resonance signals of methyl groups.

81%
Siemion I. Z., Sobczyk K., Wilusz T., Polanowski A.
Acta Biochimica Polonica
|
1984
|
vol. 31
|
issue 2
207-215
6
Content available remote

Design, synthesis and biological evaluation of a new bridged immunosuppressor.

71%
Szewczuk Z., Wilczyński A., Petry I., Siemion I. Z., Wieczorek Z.
|
2001
|
vol. 48
|
issue 4
1147-1150
EN
A bridged peptide with the sequence: H-Thr-Pro-Gln-Arg-Gly-Asp-Val-γ-Abu-Asn-Asp-Gln-Glu-Glu-Thr-Thr-Gly-Val-Val-Ser-Thr-Pro-Leu-Ile-Arg-Asn-Gly-OH was designed to mimic the discontinuous epitope of the HLA-DQ molecule that might interact with CD4. The bridged peptide revealed distinct suppressory effect in the humoral immune response. This result supports our suggestion that the 164-172 region of the HLA-DQ molecule may enhance its interactions with coreceptors, possibly with CD4.
7
Content available remote

Immunosuppressory activity of the cyclodimeric peptide with RGD-sequences.

62%
Szewczuk Z., Buczek P., Stefanowicz P., Krajewski K., Wieczore Z., Siemion I. Z.
|
2001
|
vol. 48
|
issue 1
121-130
EN
Our previous studies showed that the nonapeptide fragment of HLA-DQ of the sequence H-Thr-Pro-Gln-Arg-Gly-Asp-Val-Tyr-Thr-OH, located in the β164-172 loop, strongly suppresses the humoral and cellular immune responses, while its shorter analogs, H-Arg-Gly-Asp-Val-OH, H-Arg-Gly-Asp-Val-Tyr-OH and H-Gln-Arg-Gly-Asp-Val-Tyr-OH show only a weak stimulatory activity in respect to the humoral immunological response. These fragments contain the Arg-Gly-Asp (RGD) sequence, known for its importance for cellular association phenomena. Based on the crystal structure of HLA-DR1, we also designed and synthesized a cyclic analog H-Cys-Arg-Gly-Asp-Val-Tyr-Cys-OH with restricted conformation, which strongly suppresses the immune response and selectively inhibits the αvβ3 integrin, suggesting that the mechanism of the immunosuppressory action of the peptide is associated with inhibition of the integrin. In this paper we present the design and synthesis of the cyclodimeric peptide, Arg-Gly-Asp-Arg-Gly-Asp, which is also known as a selective αvβ3 inhibitor. The synthesized peptide strongly suppresses both the humoral and cellular immune response. The results support our hypothesis that the immunomodulatory activity of HLA-DQ fragments may be connected with their interactions with some particular integrins on the cell surface.
8
Content available remote

On the peptide-antipeptide interactions in interleukin-1 receptor system.

62%
Kluczyk A., Cebrat M., Zbozień-Pacamaj R., Lisowski M., Stefanowicz P., Wieczorek Z., Siemion I. Z.
|
EN
Interleukin-1 receptor antagonist (IL-1Ra) and vaccinia virus protein C10L share a VTXFYF motif, with X being Lys or Arg residue, respectively. Peptides of such sequence compete successfully with IL-1 for the cellular receptor. A pair of complementary peptides, based on the Siemion's hypothesis on the periodicity of the genetic code (QWLNIN and QWANIN), and another pair, in which, following the Root- Bernstein theory, Lys was used as complementary amino acid to Phe (QWLKIK and QWAKIK), were investigated for the peptide-antipeptide interactions using mass spectrometry (ESI-MS) and circular dichroism (CD) methods. The CD measurements indicated some conformational changes, more pronounced in the Siemion's pairs, however, no heterodimer formation was found by MS. In the region of IL-1 receptor situated close to the position of IL-1Ra in the IL-1Ra-receptor complex, a KQKL motif is present, suggesting a possibility of complementary recognition of the Root-Bernstein type in the IL-1 receptor. The biological activity of the complementary peptides is similar to that of the original ones. They efficiently compete with IL-1 and show moderate immunosuppressory activity in humoral and cellular immune response. The inhibition of the IL-1-IL-1 receptor interaction may result from the complementary peptides acting as mini-receptors with affinity for IL-1.
first rewind previous Page / 1 next fast forward last
JavaScript is turned off in your web browser. Turn it on to take full advantage of this site, then refresh the page.