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J Augustyniak

Publications and source records attributed to J Augustyniak.

13 recordsLinked to original sources
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↗
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↗
PubMed1976

Large-scale isolation of tRNA from barley embryos.

1. Large-scale isolation of tRNA from barley embryos is described, involving: phenol extraction, RNA deproteinization with the chloroform-isoamyl alcohol mixture, batch sorption on DEAE-cellulose, NaCl gradient elution of tRNA from DEAE-cellulose, and deaminoacylation of tRNA in the presence of bentonite. The procedure yielded tRNA free of protein and RNase activity. 2. The amino acid acceptor activity of the crude barley tRNA, its melting profiles and chromatographic patterns on Sephadex G-100 and BD-cellulose were similar to those of tRNA from other sources.

Amino Acyl-tRNA Synthetases↗