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M Krauskopf

Publications and source records attributed to M Krauskopf.

47 records · Page 3Linked to original sources
PubMed1976

Studies on fish liver protein synthesis. II. Factors influencing the aminoacylation of shark liver transfer ribonucleic acid.

The influence of buffer, pH, Mg2+, ATP, Na+, K+ and temperature on the extent and rate of aminoacyl-tRNA synthesis was studied with the shark Mustelus mento liver tRNAs and aminoacyl-tRNA synthetases. The optimum pH for the aminoacylation of tRNAMet was 8.3 and for tRNAVal 7.0. For these two tRNAs the Mg2+ optimum was related to the levels of ATP required and to the pH of the reactions. It is suggested that the Mg2+ concentration required for each aminoacylation system reflects the true conditions under which the substrate for the enzyme, the MgATP2- complex, is formed. The effect of monovalent cations was also examined. Val-tRNA synthesis was slightly stimulated up to a concentration of 50 mM NaCl (KCl). Over 100 mM salt, a rapid inhibition was observed. Met-tRNA synthesis behaves differently by being stimulated over a wide range of salt concentrations.

Acetylation↗
PubMed1974

Heterologous mischarging as a means of tRNA fractionation. I. Behaviour of E. coli phenylalanyl-tRNA(1Val) on BD-cellulose.

The chromatographic behaviour of E.coli tRNA(Val) (1), Val-tRNA(Val) (1) and Phe-tRNA(Val) (1) was studied on BD-cellulose columns. At pH 4.0 and 4 degrees C the elution position of Phe-tRNA(Val) (1) was not affected by the presence of absence of Mg(2+), whereas Val-tRNA(Val) (1) was slightly retarded when Mg(2+) was ommited. It is postulated that the amino acid and its nature influence the structure that the aminoacyl-tRNA assumes. Under suitable conditions the heteroaminoacylated Phe-tRNA(Val) (1) eluted significantly later than other tRNAs. This fact showed that heterologous mischarging can be a useful step in tRNA purification methods.

Chromatography, DEAE-Cellulose↗