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J Augustyniak

Publications and source records attributed to J Augustyniak.

At least 19 recordsLinked to original sources
PubMed1995

Expression of the plum pox coat protein gene in transgenic Nicotiana tabacum plants.

Plant expression vector pBI 121 containing the gene encoding coat protein of Plum Pox Virus of the Skierniewice isolate (CP PPV-S) was prepared (clone pCM1). The construct was used for transformation of Nicotiana tabacum plants using an Agrobacterium tumefaciens based system. About 82% of kanamycin resistant plant lines contained a transgene (the sequence of CP PPV-S) but only 81% of them actively expressed the PPV-S coat protein gene as measured by RT-PCR.

Agrobacterium tumefaciens↗
PubMed1994

Nucleotide sequence of the coat protein gene of the Skierniewice isolate of plum pox virus (PPV).

The coat protein (CP) gene of the Skierniewice isolate of plum pox virus (PPV-S) has been amplified using the reverse transcription--polymerase chain reaction (RT-PCR), cloned and sequenced. The nucleotide sequence of the gene and the deduced amino-acid sequence of PPV-S CP were compared with those of other PPV strains. The nucleotide sequence showed very high homology to most of the published sequences. The motif: Asp-Ala-Gly (DAG), important for the aphid transmissibility, was present in the amino-acid sequence. Our isolate did not react in ELISA with monoclonal antibodies MAb06 supposed to be specific for PPV-D.

Amino Acid Sequence↗
PubMed1992

Conserved signals in the 5' flanking region of eukaryotic nuclear tRNA genes.

The statistical analysis of 5' flanking regions of eukaryotic tRNA genes was done. The analysis of nucleotides in the sequence of fungi and invertebrates showed a high content of A and T in the flanking regions versus coding regions where G and C dominate. In contrast to these results in vertebrates sequences the preferences of any nucleotide in flanking regions was not observed. The analysis of tetrads showed five conserved signals: TTGT, (T/A)(T/A)ATA, A(C/T)(C/A)A in the tRNA genes of fungi, (A/T)TGA of invertebrates and (A/T)GAG of vertebrates. The analysis of 3' flanking regions did not show any conserved signals except well known poly-T tracks.

Animals↗
PubMed1989

A nuclear tRNA(UGASer) gene from the wheat Triticum vulgare var. Aria.

The nucleotide sequence of a wheat nuclear tRNA(UGASer) gene from Triticum vulgare var. Aria has been determined. It has a typical intragenic promoter with boxA and boxB elements and a putative termination signal 12 nucleotides downstream from the last tRNA-coding nucleotide. The region upstream from the coding segment contains a G + C-rich sequence with a symmetrical element. The sequence described is the first nuclear tRNA gene from a monocotyledonous plant.

Base Composition↗
PubMed1988

Iodo-Gen-mediated radioiodination of nucleic acids.

Iodo-Gen (1,3,4,6-tetrachloro-3a,6a-diphenylglycoluril), widely used as an oxidizing agent for iodination of proteins, can also be used for iodination of nucleic acids. Optimal conditions were determined for efficient labeling of RNA and DNA with 125I. The proposed procedure for radioiodination of nucleic acids is more beneficial than the methods utilizing TlCl3 because of the milder reaction conditions, the simplicity and completeness of separation of reaction products from the oxidizing agents, and the absence of a toxic catalyst. Using the standard procedure for Iodo-Gen-mediated iodination a specific radioactivity of up to 1.3 X 10(9) dpm/micrograms RNA can be achieved. The proposed procedure is also suitable for radioiodination of DNA.

DNA↗
PubMed1981

Is Tb3+ fluorescence enhancement only due to binding to single stranded polynucleotides.

Enhancement of Tb3+ fluorescence upon binding to double-stranded ribo- and deoxyribo-duplexes was investigated. It was observed that certain double stranded ribopolynucleotides completely quenched the Tb3+ fluorescence and others did not. It is concluded that the nature of the base in the duplex is critical for this enhancement. - Polydeoxyduplexes also showed enhancement of Tb3+ fluorescence, but much higher terbium concentrations were necessary to obtain similar fluorescence signals, indicative of unspecific effects. CD spectra evidence considerable conformational changes of these duplexes, in particular poly(dG-C) . poly(dG-C( which assumes the Z-form in 0.1 nM Tb3+.

Kinetics↗
PubMed1981

Gel mapping of wheat and lupin tRNAs.

Transfer RNAs were isolated from plants representing mono- and dicotyledons: wheat embryos and lupin seeds. The two tRNA preparations were compared by polyacrylamide-gel-electrophoresis mapping. Transfer RNAs extracted from the separated spots were tested for acceptance of 11 amino acids. Comparison of electrophoretic mobility of respective tRNA species indicates the overall similarity of tRNA populations in the two plants studied. Especially, isoaccepting tRNAs for glycine, tyrosine and valine and some of isoacceptors of tRNAArg, tRNAAsp, tRNALeu, tRNALys and tRNAPhe occupy identical or closely similar positions on both polyacrylamide-gel maps. However, some tRNA isoacceptors from one population have no counterparts in the second one, which may indicate differences in their primary structures.

Electrophoresis, Polyacrylamide Gel↗
PubMed1980

Valyl-tRNA and leucyl-tRNA synthetases in wheat germ and seedlings.

Valyl- and leucyl-tRNA synthetases (Val-RS and Leu-RS) isolated from wheat germ and seedlings were separated by chromatography on hydroxylapatite into organellar (Val-RS I and Leu-RS I) and cytoplasmic (Val-RS II and Leu-RS II) enzymes; the enzyme extracted from isolated chloroplasts and mitochondria corresponded to the RS I fractions. It was proved by RPC-5 chromatography of tRNA Val that Val-RS I and Val-RS II recognized all five isoacceptor tRNA Val species both from wheat germ and leaves, as well as tRNA Val from E. coli. However, out of the six isoacceptor tRNA Leu species, Leu-RS II aminoacylated two cytoplasmic species only, while Leu-RS I, the remaining four organellar tRNA Leu fractions. Both leucyl-tRNA synthetases charged E. coli tRNA, Leu-RS I more effectively than Leu-RS II. The absence of fraction RS I in cytosol seems to indicate that valyl- and leucyl-tRNA synthetases (coded for by the nuclear genome) were modified to the organellar forms after (or during) passage into organelles.

Amino Acyl-tRNA Synthetases↗
PubMed1978

Nucleotide sequence of the anticodon region of barley embryo phenylalanine transfer RNA.

Highly purified tRNAPhe from barley embryos was completely digested with pancreatic ribonuclease and T1 ribonuclease. The digestion products were separated using DEAE-cellulose chromatography. The Y base-containing fragment of the anticodon region of tRNAPhe has the following nucleotide sequence: Cpm2(2)GppsipCpApGpApCmpUpGmpApApYpAppsipCpUpGp, i.e. the same as in the anticodon region of wheat germ and pea tRNAPhe.

Anticodon↗
PubMed1977

Dependence of tRNA structure in solution upon ionic condition of the solvent. Fluorescence studies of monovalent cation binding to tRNAPhe from barley embryos.

Dependence of barley phenylalanine tRNA (tRNAPhe) fluorescence intensity at 430 nm upon LiCl, NaCl, KCl, CsCl or NH4Cl concentration was measured in 0.01 M Tris-HCl, pH 7.5, 0.001 M Na2EDTA solutions. Increase of monovalent cation concentration in the solvent from 0 to 2 M induced about 3-fold fluorescence intensity enhancement. The fractional fluorescence change was used as a measure of bound ligand concentration. Fluorescence Scatchard plots revealed three classes of monovalent cation binding sites on the tRNA molecule: interacting (strong) and independent (weak and very weak) sites. Calculated from Scatchard plots binding constants (K), for strong and weak binding of monovalent cations (in the case of Na+ binding: Ks = 26 M-1 and Kw = 4.3 M-1 respectively) exhibit linear dependence upon ionic radius (r). Two limiting values obtained from the plot of K versus r: K(max) at r = 0 r(max) at K = 0, characterize additionally strong and weak monovalent cation binding sites (Ks(max) = 42 M-1 Kw(max) = 8.5 M-1, rs(max) = 0.23 nm and rw(max) = 0.22 nm). A model of the relationship between weak Mg2+ binding sites and monovalent cation binding sites as well as of monovalent cations binding to tRNA is proposed.

Cations, Monovalent↗
PubMed1977

Leucine transfer RNA from barley. Characterization and purification of isoaccepting species.

Barley embryo leucine tRNA separated on reversed-phase chromatography-5 (RPC-5) into 5 fractions, whereas tRNA isolated from barley seedlings grown both in the light and in the dark, contained 4 species of tRNALeu. Species 2 and 3 were predominant; their relative ratio changed depending upon the growth conditions of the seedlings. Fractionation of crude barley tRNA successively on BD-cellulose, RPC-5 and Sepharose 4B enabled preparative isolation and purification of four leucine isoaccepting tRNAs. The species isolated differed in their main nucleotide composition, melting profiles and MgCl2 titration curves.

Darkness↗