Structural properties of ribosomal protein L11 from Escherichia coli

Protein L11 has been isolated from the large subunit of the E. coli ribosome under non-denaturing conditions and studied by proton magnetic resonance spectroscopy, limited proteolysis, and fluorescence and UV spectroscopy. The protein consists of two domains, a tightly-folded N-terminal part and a C-terminal half with an extended and loosely folded conformation. It is likely that the N-terminal domain is located on the surface of the subunit whereas the C-terminal part is buried within the ribosomal structure. The two tyrosines in the N-terminal region behave as solvent-exposed residues, in good agreement with iodination studies on L11 in situ. It appears probable that the central region of L11, in which the protease cleavages occur, plays an important part in structural and functional aspects.