Wyniki wyszukiwania - Biblioteka Nauki

1

The criteria of life and aging from a molecular viewpoint. The role of protein aggregation in the process of aging

100%

Spólnik P. , Konieczny L. , Piekarska B. , Rybarska J. , Stopa B. , Zemanek G.

|

tom Vol. 7, no. 1

23--30

EN

Biological knowledge is expanding rapidly, delving deep into nature’s mechanisms. However, the essence of life as a molecular process still remains unclear. Organized and independently operating biological systems are commonly thought to be living. Unfortunately, these characteristics are too general and altogether insufficient to accurately delimit the boundaries of life. The problem of the relation of many primitive biological entities to the living world is still open. The properties of self-dependent biological systems clearly derive from their highly organized automatic nature. The comparative analysis of genomes of primitive biological organisms seems to be the most promising approach, which may eventually lead to the understanding of life at the molecular level and its definition. The erythrocyte appears to be of particular interest as a model of a living system that is at a boundary. Its biological origin, automatically controlled metabolism, and programmed death sharply defined in time qualify it as the living structure, even though it is completely deprived of a genetic apparatus. However, its membership among living systems seems to be well-founded. Protein aggregation is one of the common characteristics of aging. It is a consequence of abnormalities of protein structure induced by destructive actions but also by abnormalities of synthesis. Aggregation of membrane proteins probably affects the activity of certain enzymes or transport proteins, which are important as energy providers for aging erythrocytes. After the erythrocyte has passed through the vascular system a given number of times, it is not able to undergo a certain set of indispensable metabolic rearrangements. A living thing is then a form of animated nature which has the features of independence as a result of automation and possesses its own compatible with nature program of action which is time-limited beforehand.

2

Supramolecularity creates nonstandard protein ligands

100%

Piekarska B. , Rybarska J. , Stopa B. , Zemanek G. , Krol M. , Roterman I. , Konieczny L.

|

nr 4

EN

Congo red and a group of structurally related dyes long used to stain amyloid proteins are known to associate in water solutions. The self-association of some dyes belonging to this group appears particularly strong. In water solutions their molecules are arranged in ribbon-like micellar forms with liquid crystalline properties. These compounds have recently been found to form complexeswith some native proteins in a non-standard way. Gaps formed by the local distribution of β-sheets in proteins probably represent the receptor sites for these dye ligands. They may result from higher structural instability in unfolding conditions, but also may appear as long range cooperative fluctuations generated by ligand binding. Immunoglobulins G were chosen as model binding proteins to check the mechanism of binding of these dyes. The sites of structural changes generated by antigen binding in antibodies, believed to act as a signal propagated to distant parts of the molecule, were assumed to be suitable sites for the complexation of liquid-crystalline dyes. This assumption was confirmed by proving that antibodies engaged in immune complexation really do bind these dyes; as expected, this binding affects their function by significantly enhancing antigen binding and simultaneously inhibiting C1q attachment. Binding of these supramolecular dyes by some other native proteins including serpins and their natural complexes was also shown. The strict dependence of the ligation properties on strong self-assembling and the particular arrangement of dye molecules indicate that supramolecularity is the feature that creates non-standard protein ligands, with potential uses in medicine and experimental science.

3

Tworzenie i rozdział kompleksów białek surowicy z barwnikami supramolekularnymi w elektroforezie dwukierunkowej - próba opracowania komputerowej techniki analizy obrazu rozdziałowego

84%

Rybarska J. , Spólnik P. , Drozd A. , Konieczny L. , Piekarska B. , Stopa B. , Zemanek G. , Król M. , Roterman-Konieczna I.

|

tom Vol. 1, no. 1/2

133--138

PL

Praca przedstawia badania eksperymentalne mające na celu wykrycie zmian w składzie białkowym zmienionej chorobowo surowicy ludzkiej. Dla wykrycia zmian opracowano dwukierunkową technikę elektroforetyczną umożliwiającą tworzenie kompleksów przez barwniki o charakterze ciekłokrystalicznym z białkami. Taśmowe micele barwnika mogą przylegać do szkieletu łańcucha polipeptydowego w obszarach jego ekspozycji, tworząc kompleksy. Warunki elektroforetyczne pozwalają na usunięcie nadmiaru oraz puli słabo związanego z białkami barwnika. Tworzenie kompleksów w elektroforezie pozwala na ujawnienie kompleksów białek z barwnikami, które wędrują szybciej niż białka niezaangażowane w wiązanie barwnika. Nieprawidłowe oraz przejściowo zdestabilizowane natywne białka mogą być podatne na penetrację i wiązanie dużych supramolekularnych ligandów. Do grupy białek wiążących należą białka szpiczakowe oraz serpiny, haptoglobiny i immunoglobuliny, ulegające przegrupowaniu podczas tworzenia kompleksów ze swoimi fizjologicznymi ligandami. Elektroforeza surowicy prowadzona jest dwuetapowo w prostopadłych względem siebie kierunkach. Pierwszy rozdział jest standardowy. Drugi modyfikowany jest przez kontakt i ewentualną interakcję rozdzielonych uprzednio białek z dodanym barwnikiem. Szybciej wędrujący barwnik, którego punkt nałożenia znajduje się poniżej białek, napotyka w trakcie wędrówki i wyprzedza białko. Białka zdolne do tworzenia kompleksów zabarwiają się w takich warunkach oraz wędrują szybciej od swoich nieskompleksowanych z barwnikiem odpowiedników. Po redukcji barwników dwutioninem sodowym z następowym zabarwieniem błękitem bromofenolowym, można uzyskać kompletny proteinogram rozdzielanej surowicy. Próby opracowania pół-automatycznej i automatycznej analizy uzyskiwanego w elektroforezie rozdziału plam zostały ostatnio podjęte.

EN

Two-dimensional agarose electrophoresis was used to create suitable conditions for the formation of protein complexes with supramolecular dyes. Ribbon-shaped dye molecule ligands adhere during complexation to the polypeptide backbone of β-conformation within protein clefts. The electrophoresis helps to remove the dye excess and the dye weakly attached to protein molecules. It simultaneously allows for the exposure of protein-dye complexes migrating faster than proteins not engaged in complexation. Abnormal and transiently destabilized native proteins become susceptible to penetration and binding by large supramolecular dye ligands. This includes many myeloma proteins as well as serpins, haptoglobins and immunoglobulins engaged in their natural complexes. Electrophoresis of serum proteins is conducted in two steps: the first is a standard electrophoresis while the second (perpen-dicular run) is modified by the contact and interaction of separated serum proteins (during the first step) with the added dye. The fast migrating dye, for which the starting position is retreated versus to that of proteins, meets and overruns the proteins. The proteins which are susceptible to dye penetration and binding become stained and their migration is accelerated. The complete proteinogram including the binding and non-binding dye proteins may be revealed by standard staining with bromophenol blue after removal of the supramolecular dye. An attempt for semi-automatic or automatic analysis of spots distributed in electrophoresis has been undertaken.

4

The structure and protein binding of amyloid-specific dye reagents

84%

Stopa B. , Piekarska B. , Konieczny L. , Rybarska J. , Spolnik P. , Zemanek G. , Roterman I. , Krol M.

|

nr 4

EN

The self-assembling tendency and protein complexation capability of dyes related to Congo red and also some dyes of different structure were compared to explain the mechanism of Congo red binding and the reason for its specific affinity for /3-struc- ture. Complexation with proteins was measured directly and expressed as the number of dye molecules bound to heat-aggregated IgG and to two light chains with different structural stability. Binding of dyes to rabbit antibodies was measured indirectly as the enhancement effect of the dye on immune complex formation. Self-assembling was tested using dynamic light scattering to measure the size of the supra- molecular assemblies. In general the results show that the supramolecular form of a dye is the main factor determining its complexation capability. Dyes that in their compact supramolecular organization are ribbon-shaped may adhere to polypeptides of /3-conformation due to the architectural compatibility in this unique structural form. The optimal fit in complexation seems to depend on two contradictory factors involving, on the one hand, the compactness of the non-covalently stabilized supra- molecular ligand, and the dynamic character producing its plasticity on the other. As a result, the highest protein binding capability is shown by dyes with a moderate self-assembling tendency, while those arranging into either very rigid or very unstable supramolecular entities are less able to bind.

5

Protein distorsion-derived mechanism of signal discrimination in monocytes revealed using Congo red to stain activated cells

84%

Zemanek G. , Rybarska J. , Stopa B. , Piekarska B. , Spolnik P. , Konieczny L. , Roterman I. , Bugajski A.

|

nr 3

6

The use of the Congo red-related dye DBACR to recognize the heavy chain-derived abnormality of myeloma immunoglobulins

67%

Spolnik P. , Konieczny L. , Piekarska B. , Rybarska J. , Stopa B. , Zemanek G. , Drozd A. , Krol M. , Roterman I. , Wolska-Smolen T. , Skotnicki A. B.

|

tom 54

|

nr 3