Maria Markiewicz

The effect of lupin alkaloids and ethanol extracts from seeds of Lupinus angustifolius on selected bacterial strains

Summary The following pure alkaloids were isolated from lupin seeds ( L. angustifolius var. Mirela): lupanine, 13-OH-lupanine, angustifoline and a 48 % ethanol extract. They and the commercial sparteine were tested for bacteriostatic effects against pathogenic bacteria, namely, Gram-positive ( Staphylococcus aureus ATCC 25923, Bacillus subtilis ATCC 6633) and Gram-negative ( Escherichia coli ATCC 25922, Pseudomonas aeruginosa ATCC 27853); a strain of Gram-positive Bacillus thuringiensis HD-4 with sporeforming rods, isolated from soil, was also tested. The established bacteriostatic agents, e.g. antibiotics, are active at a concentration 3 to 4 orders of magnitude lower than the tested lupin alkaloids. Therefore a bacteriostatic effect is possible in plants under physiological conditions, but a pharmaceutical application of these products as bacteriostatic agents is rather unlikely. The presented data support the allelopathic function of alkaloids.

Synthetic oligonucleotide combinatorial libraries and their applications.

The application of synthetic oligonucleotide combinatorial libraries is described in the studies of triplex DNA. A new method of selection of dispersed (beaded) oligonucleotide combinatorial libraries based on the use of streptavidin magnetic beads is presented. A combinatorial chemistry approach is also proposed for studies of polyaminooligonucleotides.

Synthesis of A Polyaminooligonucleotide Combinatorial Library

Abstract A new method of synthesis of phosphoramidite of 2′-deoxycytydine carrying a protected spermine moiety at N-4 position is described. A model oligodeoxyribonucleotide containing the specified nucleoside unit has been synthesised. A synthesis of a polyaminooligonucleotide combinatorial library was carried out. The analysis of the above library clearly shows that the presence of spermine moieties in oligodeoxyribonucleotides increases stability of their duplexes.

Species-specific Inhibitory Effect of Lupine Alkaloids on Translation in Plants

Summary The following lupine alkaloids: lupanine, 13-OH-lupanine, and angustifoline isolated fromthe seeds of L. angustifolius cv. Mirela, and commercial sparteine have been tested for their effect on selected steps of protein biosynthesis: aminoacylation of tRNA Phe and enzymatic binding of Phe-tRNA Phe to poly-U programmed ribosomes. We found that only one of these two steps-namely the binding reaction, is effected by alkaloids. Following this observation, evidence is presented that the inhibitory properties of these alkaloids are species-specific. Higher inhibitory effect (two- to ten-fold) was observed on wheat germ system (alkaloid-free) in comparison to the translational system originating from bitter lupine ( L. albus cv. Pop). On the basis of these observations we concluded that the sensitivity of the system is correlated with the presence of endogenous alkaloids which probably participate in internal interactions.

Synthesis of Polyaminooligonucleotides and Their Combinatorial Libraries

Abstract A synthesis of phosphoramidites of 2′-deoxyadenosine and 2′-deoxyguanosine carrying a protected spermine moiety at N-6 and N-2 positions respectively is described. An approach to analyse properties of polyaminooligonucleotides using their synthetic combinatorial libraries is described and discussed. A synthesis of a polyaminooligonucleotide combinatorial library was carried out and the analysis of the library clearly showed that the presence of spermine moieties in oligodeoxyribonucleotides increases stability of their complexes.

Synthetic Oligonucleotide Combinatorlal Libraries - Tools For Studying Nucleic Acid Interactions

Abstract This paper gives an overview of methods available for, and difficulties encountered in the preparation of synthetic oligonucleotide combinatorial libraries. The application of libraries immobilized to high-load beads to the screening of specific two-component (nucleic acid / nucleic acid) and three-component (ds nucleic acidprotein) interactions is described. The effector oligonucleotides immobilized to a single bead are identified by direct Maxam-Gilbert sequencing.