The conformational stability of ribosomal proteins L7 and L12 from E. coli. I. Circular dichroism study of the changes induced by ionic strength and solvents
Year: 1973
Type: article
Abstract: Ribosomal proteins L7 and L12 are the only acidic proteins found on the 50S ribosomal subunit of Escherichia coli. The effect of ionic strength, helix‐promoting solvents and denaturating agents on the conformation of these proteins has been studied. It has been established that the helicity of L7 and L12 proteins (approx. 45–50% α helix) can be increased to 60–70% when they are exposed to helix‐promoting solvents such as methanol or ethanol in the presence of 0.1M salt. High ionic strength by itself was without any effect on the conformation of the proteins. However, the solvent, 2,2,2‐trifluoroethanol increased the content of α helices up to 80% even in the absence of salt. Denaturating agents like urea (6M) or guanidine HCl (6M), decreased the content of the ordered structure below 20%. All conformational changes induced by salt or solvents were completely reversible and characterized by a broad transition showing a low degree of cooperativity. This might indicate the presence of discrete segments with variations in amino acid sequences and ordered structures with different stabilities.
Source: Biopolymers
Language: English
Subfield: Molecular Biology
Domain: Life Sciences
Open Access status: hybrid
Estimated APC paid: $4,150
OpenAlex ID: W2042609300