Studies on the structure of protein L7/L12 from Escherichia coli ribosomes.

Circular dichroism, infrared and proton magnetic resonance spectroscopy as well as microcalorimetry methods were used to investigate the intact proteins L7/L12 in solution and their different derivatives (L7 with oxidized residues of methionine, fragments 27--120, 1--73 and 74--120)- On the basis of the data obtained the following conclusions have been drawn: (a) there is no beta structure in the protein L7, (B) the N-terminal region of L7 forms a long alpha helix (c) the Phe-30 residue within the N-terminal region of L7 takes part in the dimerization, (d) the C-terminal of L7 is globular and (e) the Phe-54 residue is included in the hydrophobic core of the globular C-terminal region.