On the Renaturation of Ribosomal Protein L11

Abstract

When urea‐denatured preparations of protein L11 from the ribosome of Escherichia coli are introduced into physiological buffers, two completely different configurations can be obtained. One form, by NMR criteria, shows little evidence of stable tertiary interactions; the other shows strong indications of a distinctive folding pattern. The configuration obtained depends on minor details of the method used for returning samples to non‐denaturing conditions.

Cloning, purification and characterization of the ribosomal protein L11 from E. coli

“…Some physicochemical characteristics of ribosomal protein L11 were determined on the protein, isolated from native E. coli ribosomes [1,4,5]. The obtained structural data in this study, were the ribosomal protein L11 was over-expressed in E. coli and purified in non-denaturing and denaturing conditions, are similar to that reported before for L11, directly purified from E. coli ribosomes.…”

“…The obtained structural data in this study, were the ribosomal protein L11 was over-expressed in E. coli and purified in non-denaturing and denaturing conditions, are similar to that reported before for L11, directly purified from E. coli ribosomes. The over-expressed protein L11 is folding properly and the presence of N-terminal Met in the cloned protein (removed in the endogenous protein L11 from the native ribosomes) and the big concentration difference between the cytoplasm (where L11 is in soluble form), the including bodies (where L11 is in insoluble form) and the ribosomes (where L11 is in bound form; in E. coli it was about 10 μg/ml [5]) does not affect the structure of protein. At temperatures higher than 37˚C the protein L11 is aggregating because of denaturation, increasing with the concentration of protein and decreasing with the salt concentration up to 1 M. The reported thermal denaturation of protein L11 showed low thermostability with a transition of about 50˚C.…”

Nuclear Overhauser experiments at 500 MHz on the downfield proton spectra of 5S ribonucleic acid and its complex with ribosomal protein L25

“…It has been shown that the large 5S RNA fragment derived from the whole molecule by limited ribonuclease A (RNase A) digestion (Douthwaite et al, 1979) has a secondary, and probably a tertiary, structure similar to that of 0006-2960/83/0422-2622$01.50/0 © 1983 American Chemical Society the same sequences in intact 5S RNA (Kime & Moore, 1983a). NOE methods have produced data consistent with the presence of the two helical stems predicted to lie within the fragment sequence (bases 1-11, 69-87, and 89-120) by the Fox-Woese (1975) model for the parent, 5S RNA secondary structure (Kime & Moore, 1983b). This paper reports the results of a series of observations made on the downfield spectra of Escherichia coli 5S RNA, its complex with ribosomal protein L25 [see Garrett et al (1981)], and the corresponding L25-fragment complex (Douthwaite et al, 1979).…”

A Chemical interference study on the interaction of ribosomal protein L11 fromEscherichia coliwith RNA molecules containing its binding iste from 23S rRNA

“…Modified and untreated control RNA (normally 6 jttM) was renatured at 42°C for 15 min in 5 MtL of binding buffer, followed by slow cooling to room temperature and 10 min on ice. Protein L 1I (10 ,/L) was heated at 42°C for 30 min, slow cooled to room a temperature, and chilled on ice for 10 min (29). Complex formation was carried out on ice for 1.5 h at a protein:RNA molar ratio of 2:1.…”