Biomedical subjects

M Bartsch

Publications and source records attributed to M Bartsch.

21 records · Page 2Linked to original sources

PubMed1983

Chemical modification of 5S and 4.5S rRNAs in situ in spinach chloroplast ribosomes.

Spinach chloroplast ribosomes and 50S subunits were reacted with diethylpyrocarbonate under conditions in which their gross structures can be maintained. 5S and 4.5S rRNAs were isolated from such modified particles and the modified adenine residues of these rRNAs were identified by using gel sequencing method. The accessible sites of 5S rRNA in 50S subunits to the reagent were found to be A15, A40 and A89 and that of 5S rRNA in whole ribosomes was restricted to A89. In the case of 4.5S rRNA, A33 was exclusively modified in ribosomes or 50S subunits.

Chloroplasts↗

PubMed1982

Copies of protein S6 in Escherichia coli ribosomes.

A reinvestigation of the copy number of protein S6 in Escherichia coli ribosomes shows that there is only one copy of S6 in 30 S subunits and in 70 S ribosomes. The previously reported higher value (Subramanian, A. R. (1980) J. Biol. Chem. 255, 6941-6946) is shown to arise from the presence in the usual ribosome preparations of a protein which co-electrophoreses with S6 but does not react with S6 antiserum. This protein is removed when ribosomes are purified by passage through a sucrose gradient.

Centrifugation, Density Gradient↗

PubMed1982

Purification, primary structure, and homology relationships of a chloroplast ribosomal protein.

A chloroplast ribosomal protein that showed immunological homology to Escherichia coli ribosomal protein L12 was purified from spinach (Spinacia oleracea) leaves and its primary structure was determined by manual micro Edman degradation. The protein is composed of 130 amino acid residues and has M(r) 13,576. It shows structural features characteristic of the L12 proteins of eubacterial 70S ribosomes (e.g., identical amino acid residues in about 50% of the sequence) but no apparent homology to the L12-type proteins of eukaryotic cytoplasmic 80S ribosomes. The homology to eubacterial proteins is highest in the COOH-terminal region (70%) and low in the NH(2)-terminal region (<20%).

Journal Article↗