Wyniki wyszukiwania

1

Starch metabolism in leaves

100%

Orzechowski S.

Acta Biochimica Polonica

|

2008

|

tom 55

|

nr 3

435-445

Starch is the most abundant storage carbohydrate produced in plants. The initiation of transitory starch synthesis and degradation in plastids depends mainly on diurnalcycle, post-translational regulation of enzyme activity and starch phosphorylation. For the proper structure of starch granule the activities of all starch synthase isoenzymes, branching enzymes and debranching enzymes are needed. The intensity of starch biosynthesis depends mainly on the activity of AGPase (adenosine 5’-diphosphate glucose pyrophosphorylase). The key enzymes in starch degradation are β-amylase, isoamylase 3 and disproportionating enzyme. However, it should be underlined that there are some crucial differences in starch metabolism between heterotrophic and autotrophic tissues, e.g. is the ability to build multiprotein complexes responsible for biosynthesis and degradation of starch granules in chloroplasts. The observed huge progress in understanding of starch metabolism was possible mainly due to analyses of the complete Arabidopsis and rice genomes and of numerous mutants with altered starch metabolism in leaves. The aim of this paper is to review current knowledge on transient starch metabolism in higher plants.

2

Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik

Enzymy biorące udział w biosyntezie i rozkładzie skrobii w roślinach

63%

Dobrzynska U. E., Orzechowski S.

Postępy Nauk Rolniczych

|

2004

|

tom 51

|

nr 5

3

Identyfication and partly purification a novel homologue of glucan, water dikinase (GWD) from Solanum tuberosum L.

63%

Orzechowski S., Felus M.

Acta Biochimica Polonica

|

2006

|

tom 53

|

nr Supplement 1

4

Nowe spojrzenie na proces degradacji ziaren skrobi w chloroplastach Arabidopsis thaliana L.

63%

Samojedny D., Orzechowski S.

Postępy Biochemii

|

2007

|

tom 53

|

nr 1

74-83

5

QSAR analysis in studies on the acute toxicity of insecticides to aquatic organisms

51%

Murawa D., Warminski K., Sulima J., Orzechowski S.

Polish Journal of Natural Sciences

|

2006

|

tom 21

871-881

6

The role of thaumatin II in cucumber resistance against Tetranychus urticae Koch: laboratory and greenhouse evaluation

51%

Kielkiewicz M., Czarnecka M., Orzechowski S., Szwacka M.

Biological Letters

|

2009

|

tom 46

|

nr 2

7

Analiza funkcjonowania genow

51%

Sitnicka D., Figurska K., Orzechowski S.

Postępy Biologii Komórki

|

2009

|

tom 36

|

nr 4

503-516

8

Purification and properties of alanine aminotransferase from maize [Zea mays L.] leaves

51%

Orzechowski S., Socha-Hanc J., Paszkowski A.

Acta Physiologiae Plantarum

|

1999

|

tom 21

|

nr 4

9

Subcellular distribution of alanine aminotransferase activity in maize [Zea mays L.] leaves

51%

Orzechowski S., Socha-Hanc J., Paszkowski A.

Acta Physiologiae Plantarum

|

1999

|

tom 21

|

nr 4

10

Alanine aminotransferase and glycine aminotransferase from maize [Zea mays L.] leaves

51%

Orzechowski S., Socha-Hanc J., Paszkowski A.

Acta Biochimica Polonica

|

1999

|

tom 46

|

nr 2

Alanine aminotransferase (AlaAT, EC 2.6.1.2) and glycine aminotransferase (GlyAT, EC 2.6.1.4), two different enzymes catalyzing transamination reactions with L-alanine as the amino-acid substrate, were examined in maize in which alanine participates substantially in nitrogen transport. Preparative PAGE of a partially purified preparation of aminotransferases from maize leaves gave 6 fractions differing in electrophoretic mobility. The fastest migrating fraction I represents AlaAT specific for L-alanine as amino donor and 2-oxoglutarate as amino acceptor. The remaining fractions showed three aminotransferase activities: L-alanine-2-oxoglutarate, L-alanine-glyoxylate and L-glutamate-glyoxylate. By means of molecular sieving on Zorbax SE-250 two groups of enzymes were distinguished in the PAGE fractions: of about 100 kDa and 50 kDa. Molecular mass of 104 kDa was ascribed to AlaAT in fraction I, while the molecular mass of the three enzymatic activities in 3 fractions of the low electrophoretic mobility was about 50 kDa. The response of these fractions to: aminooxyacetate, 3-chloro-L-alanine and competing amino acids promted us to suggest that five out of the six preparative PAGE fractions represented GlyAT isoforms, differing from each other by the L-glutamate-glyoxylate:L-alanine-glyoxylate:L-alanine-2-oxoglutarate activity ratio.

11

Biochemical indicators of environmental contamination with heavy metals

51%

Orzechowski S., Kwinta J., Gworek B., Bielawski W.

Polish Journal of Environmental Studies

|

1997

|

tom 06

|

nr 6

Changes in activity of one of the most important enzymes of nitrogen compound metabolism - glutamate dehydrogenase (GDH EC 1.4.1.2-4) under the conditions of variable concentrations of Cd2+, Zn2+, Pb2+ were investigated. Dry matter increase and glutathione (GSH) levels varying under these conditions were also analyzed. The obtained results show a close relationship between the concentration of the investigated metal ions, especially Cd2+, and the metabolism of primary amino acids. The increase of the heavy metal concentration resulted in a many-fold GDH activity increase, significant decrease of the seedling mass, and lowering of the GSH level. The increase of GDH activity may attest to the important role of that enzyme in catabolic processes intensified under these conditions, or to the increasing importance of the reductive amination of 2-oxoglutarate in the states of physiological stress caused by the presence of heavy metals. The observed relationship concerns the plant's photosynthetizing organs rather than its root system.

12

Is quantity of protein barley forms determined by proteins localized in the subaleurone layer?

51%

Macewicz J., Orzechowski S., Dobrzynska U., Haebel S.

Acta Physiologiae Plantarum

|

2006

|

tom 28

|

nr 5

Barley biotypes from the world collection differ in their storage protein content even till 200 %. This is the first report including results of the research, in which the structure of grains containing different amount of protein was tested to explain this difference. The endosperm was investigated using scanning electron microscopy. The structure of the aleurone layer, storing large quantities of protein, did not differ between the high- and low-protein forms of barley. It has been proven that the large quantities of kernel protein may be stored in some cells of the zone adjacent to the aleurone layer, defined as the subaleurone cells. It has been shown that morphologically uniform kernels of the same plant and even of the same ear can vary greatly with respect to the number of these subaleurone cells. The purpose of the study was an examination of variation in protein structure in single kernels of a fodder, a brewery and in an extra high-protein form of barley as well. Moreover the studies were aimed to detect qualitative differences in the subaleurone protein. Application of mass spectrometry made possible the identification of several kinds of proteins which were present in subaleurne layer of kernels. In the granule-bound protein fraction isolated from the subaleurone type kernels, a much stronger representation of some protein was found, with the mo lecular mass between 29 and 45 kDa, in comparison with the low-protein kernels. It is supposed, that these protein are isoforms of z-type serpin and B3-hordein.

13

The effect of drought on the content and degradation of soluble sugars and starch in Solanum tuberosum L. leaves

33%

Orzechowski S., Cisowska I., Cania J., Chadzynska M., Marecka D., Rybarczyk-Plonska A., Jasnos J., Sitnicka D.

Acta Biochimica Polonica

|

2018

|

tom 65

|

nr S2

14

Analysis of the expression, subcellular and tissue localisation of phosphoglucan, water dikinase (PWD/GWD3) in Solanum tuberosum L.: a bioinformatics approach for the comparative analysis of two a-glucan, water dikinases (GWDs) from Solanum tuberosum L.

33%

Orzechowski S., Grabowska A., Sitnicka D., Siminska J., Felus M., Dudkiewicz M., Fudali S., Sobczak M.

Acta Physiologiae Plantarum

|

2013

|

tom 35

|

nr 02

There are several important factors affecting the rate of starch decomposition in plants, including the circadian clock, the regulation of gene expression, the regulation of enzyme activities and starch phosphorylation by glucan, water dikinase activities (GWDs). One isoform of glucan, water dikinase named GWD3 or PWD (EC 2.7.9.5) was isolated for the first time from Arabidopsis thaliana, and now we report its isolation and identification in Solanum tuberosum L. leaves and tubers. We compare StGWD3 sequence to the other GWDs sequences using bioinformatics tools and propose also structural models for the starch-binding domains in StGWD3 and StGWD1. The StGWD3 gene expression and protein were localised in different heterotrophic and autotrophic potato tissues and organs using in situ RT-PCR and immunolocalisation methods, respectively. Diurnal changes in the transcript abundance of StGWD3 in leaves were analysed using quantitative real-time PCR and they appeared to be typical for most genes involved in starch degradation in chloroplasts.

Ograniczanie wyników

Starch metabolism in leaves

Enzymy biorące udział w biosyntezie i rozkładzie skrobii w roślinach

Identyfication and partly purification a novel homologue of glucan, water dikinase (GWD) from Solanum tuberosum L.

Nowe spojrzenie na proces degradacji ziaren skrobi w chloroplastach Arabidopsis thaliana L.

QSAR analysis in studies on the acute toxicity of insecticides to aquatic organisms

The role of thaumatin II in cucumber resistance against Tetranychus urticae Koch: laboratory and greenhouse evaluation

Analiza funkcjonowania genow

Purification and properties of alanine aminotransferase from maize [Zea mays L.] leaves

Subcellular distribution of alanine aminotransferase activity in maize [Zea mays L.] leaves

Alanine aminotransferase and glycine aminotransferase from maize [Zea mays L.] leaves

Biochemical indicators of environmental contamination with heavy metals

Is quantity of protein barley forms determined by proteins localized in the subaleurone layer?

The effect of drought on the content and degradation of soluble sugars and starch in Solanum tuberosum L. leaves

Analysis of the expression, subcellular and tissue localisation of phosphoglucan, water dikinase (PWD/GWD3) in Solanum tuberosum L.: a bioinformatics approach for the comparative analysis of two a-glucan, water dikinases (GWDs) from Solanum tuberosum L.