Vol. 6 No. 4 December 2001

Volume 6 (2001) pp 859-870
Title REGENERATION OF CUPHEA WRIGHTII (PEYR 651) AND FERTILE C.WRIGHTII X C. TOLUCANA HYBRIDS FROM LEAF EXPLANTS
Authors Zbigniew Przybecki1, Jan Olejniczak2 and Elzbieta Adamska2
Abstract Callus was obtained from leaf explants of Cupea wrightii and Cuphea wrightii x Cuphea tolucana hybrid plants, and the plants were later regenerated. C. tolucana explants were capable of forming callus, but not of regenerating. In order to obtain callus from C. wrightii and the hybrid plants, the addition of BAP to the medium was necessary, whereas in the case of C. tolucana auxin was needed. The regeneration of the plants did not require auxin, and both forms (C. wrightii and the hybrids) regenerated in the same medium. The regeneration yield came to around 12 plants from the callus of one harvest. Some of the callus from the hybrids was subjected to colchicine treatment, which increased the number of fully fertile regenerants from 1% to almost 20%.
Address and Contact Information 1Department of Plant Genetics, Breeding and Plant Biotechnology, Warsaw University of Agriculture, Nowoursynowska 166, 02-787 Warszawa, Poland
2Institute of Plant Genetics, Polish Academy of Sciences, Strzeszynska 34, 60- 479 Poznan, Poland
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Volume 6 (2001) pp 871-880
Title COMPARATIVE STUDIES OF THE BIOLOGICAL ACTIVITIES OF LYSOSOMOTROPIC AMINOESTERS AND QUATERNARY AMMONIUM SALTS ON THE YEAST Saccharomyces cerevisiae
Authors Ewa Obłąk1, Tadeusz M. Lachowicz2, Jacek Łuczynski3 and Stanisław Witek3
Abstract The biological activity of lysosomotropic n-alkyl N,N-dimethylglyci- nates (DMG-n) was compared with that of a quaternary ammonium salt IM (methochloride of DMG-12). The activity of the glycinates appeared to be carbon chain length dependent and was similar at pH 6 and pH 8. Nutritional auxotrophy and respiratory deficiencies have no influence on DMG-n sensitivity. Both IM and DMG-n inhibit plasma membrane H+-ATPase activity while mitochondrial ATPase is relatively non-sensitive to glycinates. No cross- resistance to IM and DMG-n was observed.
Address and Contact Information 1Institute of Microbiology, University of Wroclaw, Przybyszewskiego 65/73, 51-148 Wroclaw, Poland;
2Institute of Biotechnology and Environmental Protection, Pedagogical University, Monte Casino 3a, 65-561 Zielona Gora, Poland;
3Departament of Chemistry, Technical University of Wroclaw, Wybrzeze Wyspianskiego, 51-148 Wroclaw, Poland
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Volume 6 (2001) pp 881-895
Title THE MECHANISM OF BILE SALT-INDUCED HEMOLYSIS
Authors Lucyna Mrowczynska and Jozef Bielawski
Abstract The hemolytic activities of sodium deoxycholate (DChol) and its tauro-conjugate (TDChol) and glyco-conjugate (GDChol) were analysed. 50 % hemolysis occurred in 30 min at pH 7.3, at the concentrations of these detergents equal to 0.044, 0.042 and 0.040 % respectively. These values are below their critical micellar concentrations. Based on its kinetics, this hemolysis is classified as being of permeability type. The detergents increase the permeability of erythrocyte membranes to KCl, and colloid osmotic hemolysis occurs. The minimum of hemolytic activity of the three cholates is at about pH 7.5. A very high increase in hemolytic activity occurs at pHs below 6.8, 6.5 and 6.2 for DChol, TDChol, and GDChol, respectively. These values are close to the pKa for DChol (6.2), but much higher than the pKa for TDChol (1.9) and GDChol (4.8). It is therefore suggested that the increase in hemolytic activity is not a result of the protonation of the anionic groups of the cholates. At acidification below pH 6, the kinetics of DChol induced hemolysis change to the damage type characterised by nonselective membrane permeability. Such a transition is not observed in TDChol and GDChol induced hemolysis. It is therefore suggested that the change in the type of hemolysis depends on protonation of the anionic group of cholates.
Address and Contact Information Department of Cytology and Histology, A. Mickiewicz University, Fredry 10, 61-701 Poznan, Poland
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Volume 6 (2001) pp 897-911
Title DNA REPAIR OF HYDROGEN PEROXIDE-INDUCED DAMAGE IN HUMAN LYMPHOCYTES IN THE PRESENCE OF FOUR ANTIMUTAGENS. A STUDY WITH ALKALINE SINGLE CELL GEL ELECTROPHORESIS (COMET ASSAY)
Authors Kazimierz Gąsiorowski* and Barbara Brokos
Abstract We assessed four antimutagenic compoundsµ influences on DNA repair in human lymphocytes exposed in vitro to hydrogen peroxide (20 μM, 5 min, at 4oC). DNA damage and repair were estimated by means of alkaline single cell gel electrophoresis (comet assay). It was noticed that the enhancement of DNA repair was relatively strongest when fluphenazine was present in the cell culture medium. In the cases of anthocyanins and alkylresorcinols, the effects were almost 6-9 times weaker than that of FPh. The effect of todralazine on DNA repair was relatively weakest. Further study should be done on fluphenazine as a potential DNA repair-enhancing compound.
Address and Contact Information Wrocław Medical University, Department of Basic Medical Sciences, Kochanowskiego 14, 51-601 Wrocław, Poland
*Corresponding author, fax: (+48 71) 3479 211, e-mail: kaz@basmed.am.wroc.pl
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Volume 6 (2001) pp 913-923
Title PROTEIN FINGERPRINTING AS A COMPLEMENTARY TOOL FOR THE CLASSIFICATION OF Pseudomonas BACTERIA
Authors Robert Zarnowski1,* , Johannes Eichel2#, Teresa Lewicka1, Henryk Rozycki3 and Stanislaw J. Pietr1
Abstract A collection of total 42 bacterial strains belonging to the genus Pseudomonas were characterised based on protein fingerprinting using sodium dodecyl sulphate polyacrylamide gel electrophoregrams of cell-free extracts. Densitometrical analysis revealed unique and distinct profiles characteristic of the studied species. This comparison differentiated the isolates into four main clusters and twelve subclusters. The obtained protein patterns have proved to be an effective and reliable method both for the classification of bacteria and for showing similarities and variability among them.
Address and Contact Information 1Agricultural University of Wrocław, Department of Agricultural Microbiology, Grunwaldzka 53, 50-375 Wrocław, Poland,
2Hans Knoll Institute for Natural Products Research, Beutenbergstrasse 11, 07745 Jena, Germany,
3Nicholas Copernicus University, Institute of General and Molecular Biology, Laboratory of Microbiology, Gagarina 9, 87-100 Torun , Poland
* Corresponding author, e-mail: robert@ozi.ar.wroc.pl
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Volume 6 (2001) pp 925-940
Title 13-CIS RETINOIC ACID AND ALL-TRANS RETINOIC ACID IN THE REGULATION OF THE PROLIFERATION AND SURVIVAL OF HUMAN BREAST CANCER CELL LINE MCF-7
Authors Ewa Czeczuga-Semeniuk, Sławomir Wołczyłski, Janusz Dzięcioł, Milena Dąbrowska, Tomasz Anchim and Izabela Tomaszewska
Abstract Retinoids are a group of compounds which inhibit cell proliferation and induce cellular differentation. The aim of this study was to compare the antiproliferative activity of various concentrations of 13-cis retinoic acid (isotretinoin) and all-trans retinoic acid (tretinoin) in a culture of the estrogen-sensitive human breast cancer cell line MCF-7.Evaluation was based on [3H]thymidine incorporation into the cancer cells and through immunocytochemical analysis of cell cycle-associated PCNA and Ki-67 protein expression. Both retinoids inhibited [3H]thymidine incorporation into the cancer cells most effectively at a concentration of 3x10-3M. Two basic substances used for line MCF-7 culture experiments, one stimulating – estradiol – and the other inhibiting – tamoxifen – were applied. Estradiol added to a culture containing decreasing concentrations of isotretinoin (from 3x10-3 to 3x10-8M)) caused a statistically significant reduction in the percentage of [3H]thymidine incorporation into the cancer cell line MCF-7, compared to the 17 β estradiol group (189.25%±62.64, control=100%, p<0.05). In the group of decreasing tretinoin concentrations, statistically significant differences were found only at 3x10-3, 3x10-4 and 3x10-8M. Following culture supplementation with tamoxifen(1μM), statistically significant differences were observed only at the highest concentrations of both retinoids (3x10-3 and 3x10-4M). The evaluation of breast carcinoma cells with a positive immunocytochemical reaction to PCNA and Ki-67 has revealed that isotretinoin reduces their percentage in the most determined and statistically significant way (38.00%±2.58 and 39.25%±3.09), compared to the control group (86.50%±9.20 and 100%±3.87, p<0.001 and p<0.0001) and to the estradiol group (87.00%±6.79 and 86.10%±7.0, p<0.001). Apart from their blocking effect on the cell cycle, retinoids also induce the apoptotic pathway.
Address and Contact Information 1 Department of Gynaecological Endocrinology, Medical Academy of Białystok, 15-276 Białystok, M. Skłodowskiej-Curie 24 A, Poland,
2 Department of Pathological Anatomy, Medical Academy of Białystok, 15-269 Białystok, Waszyngtona 13, Poland,
3Department of Hematological Diagnostics, Medical Academy of Białystok, 15-276 Białystok, M. Skłodowskiej-Curie 24 A, Poland
* Corresponding author, tel: (48) +85 746-88-18, (48)+85 746-83-43
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Volume 6 (2001) pp 941-953
Title DECREASE IN 2,2,6,6-TETRAMETHYL-PIPERIDINE-1-OXYL (TEMPO) EPR SIGNAL IN PEROXYNITRITE-TREATED ERYTHROCYTE MEMBRANES
Authors Anna Wrobel
Abstract The treatment of erythrocyte membranes with peroxynitrite (ONOO-), a cytotoxic species formed in vivo by the almost completely diffusion controlled reaction of nitric oxide (NO·) and the superoxide anion (O2-·), led to the loss of the EPR signal of the nitroxide radical 2,2,6,6- tetramethyl-piperidine-1-oxyl (TEMPO). The decrease in the TEMPO EPR signal was peroxynitrite concentration dependent in the studied peroxynitrite concentration range (100 - 1000 mM). The absence of such a phenomenon in the control membranes (not treated with peroxynitrite) and in a buffer treated with peroxynitrite indicates that the effect must be caused by nitroxide radicals reacting with the products of peroxynitrite reactions with membrane components. To find out which membrane components are responsible for the decrease in EPR signal, this effect was studied in simple model systems (protein and lipid suspensions). The same phenomenon was observed in both lipid and protein systems treated with peroxynitrite, but in protein solutions the effect was greater and occurred for lower peroxynitrite concentrations. A clear effect of the loss of the EPR signal was observed for both erythrocyte membranes and bovine serum albumin (BSA) solution for a peroxynitrite concentration of 100 mM, while in the case of linolenic acid suspension, a significant difference between control and peroxynitrite-treated samples was achieved for a peroxynitrite concentration of 1000 mM. A comparison of the results obtained for the lipid and protein systems suggests that the reaction of nitroxide radicals with protein derived species plays the main role in the observed decrease in the TEMPO EPR signal in peroxynitrite treated erythrocyte membranes.
Address and Contact Information Institute of Physics, Wrocław University of Technology, Wybrzeze Wyspiańskiego 27, 50-370 Wrocław, Poland
e-mail: wrobel@rainbow.if.pwr.wroc.pl, fax: (+4871) 3283696
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Volume 6 (2001) pp 955-970
Title EARLY DEFENCE RESPONSES IN PLANTS INFECTED WITH PATHOGENIC ORGANISMS
Authors Andrzej Talarczyk and Jacek Hennig
Abstract Plant organisms possess a complex set of defence mechanisms that are responsible for preventing unfavourable interactions with other living organisms in their natural environment or for reducing negative effects of such interactions. They can be classified into two groups: early responses that occur immediately or shortly after contact with a pathogenic organism, usually in the proximity of the infection site, and late, usually transcription- and translation- dependent responses that take part in minimizing the long-term effects of the infection and in preventing further infections. Early responses are a mixture of distinct biochemical processes, leading to quick activation of enzymes, structural changes in components of the living cell, alteration of biochemical pathways and synthesis of intra- and intercellular signals. An important part of early responses are redox processes, especially the synthesis of large amounts of reactive oxygen species.
Address and Contact Information Institute of Biochemistry and Biophysics, Polish Academy of Sciences, ul. Pawińkiego 5A, 02-106 Warszawa, Poland
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Volume 6 (2001) pp 971-984
Title COOPERATIVE COCKTAIL IN A CHEMICAL DEFENCE MECHANISM OF A TRUNKFISH
Authors Eli Kalmanzon1, Revital Aknin-Herrman1, Yocheved Rahamim2, Shmuel Carmeli2, Yechezkel Barenholz3 and Eli Zlotkin1
Abstract Pahutoxin a quaternary ammonium salt surfactant serves as an active ingredient in the defensive skin secretion of various marine trunkfish (Ostracociidae). In the defensive skin secretion of the Red Sea trunkfish, Ostracion cubicus the effect of PHN is amplified due to the existence of non toxic polypeptides which act as (a) PHN - chelators and (b) potentiators. The secretion of the Red Sea trunkfish includes an additional category of pharmacologically active polypeptides represented by boxin [7] which similarly to PHN they independently kill fish exclusively through medium application. By the aid of radiolabeled PHN and a fish gill membrane preparation a series of equilibrium saturation binding assays were carry out which demonstrate that PHN performs its biological defensive function via receptors and not due to its surface activity. The gill membranes of the trunkfish were shown to be devoid of PHNreceptors. The pharmacological, ecological and environmental implications of the above data are discussed.
Address and Contact Information 1Institute of Life Sciences, The Hebrew University, 91904 Jerusalem and Interuniversity Institute for Marine Sciences Eilat, 88103, Israel,
2School of Chemistry, Tel Aviv University, Tel Aviv 69978, Israel, 3Dept. Biochemistry, Hadassah Medical School, Hebrew University, 91120 Jerusalem, Israel.
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Volume 6 (2001) pp 985-988
1st Polish Molecular Biotechnology Conference and 3rd Seminar Of Polish Biotechnology Students' Scientific Circles, 18-20th October 2001, Gdałsk
Late Abstracts
Abstracts List CLONING AND PURIFICATION OF TWO SIMILAR SSB-LIKE PROTEINS FROM THE THERMOPHILIC BACTERIA THERMUS AQATICUS AND THERMUS THERMOPHILUS
Marcin Olszewski and Sławomir Dąbrowski - [Rozmiar: 1332 bajtĂłw]p986

CAFFEINE AND PENTOXYFFILLINE INHIBITED ACTION OF SOME CHEMICAL MUTAGENS Katarzyna Ulanowska, Jacek Piosik, Agata Czyż, Jan Kapuściński and Grzegorz Węgrzyn - [Rozmiar: 1332 bajtĂłw]p987

INHIBITION OF PHAGE DEVELOPEMENT IN LIQUID CULTURES OF E. COLI Anna Wąglewska, Marcin Łoś and Grzegorz Węgrzyn - [Rozmiar: 1332 bajtĂłw]p988