Direct shape determination of ribosomal proteins in solution and within the ribosome by means of neutron scattering.
Following the 'strategy of the glassy ribosome' single protonated ribosomal proteins (r-proteins) were reconstituted into deuterated 50S subunits of Escherichia coli. The deuteration of both rRNA and r-proteins were individually adjusted to such a degree that the ribosomal matrix appeared nearly homogeneous with respect to coherent neutron scattering and had a scattering density equivalent to a D2O solution of about 90%. Neutron scattering of ribosomal subunits was recorded in reconstitution buffer containing three different concentrations of D2O around 90% D2O (contrast variation). The signal-to-noise ratio achieved allowed us to make a direct determination of the radii of gyration of r-proteins within the 50S subunit and thus provides the first information relating to the shape of these proteins in situ. We present the radii of gyration of 11 r-proteins incorporated into 50S subunits and of 9 isolated r-proteins in solution. In addition, the data concerning the overall dimensions of the r-proteins we report on indicate that conformational changes of at least two individual r-proteins occur during the assembly process of the ribosome.
Max-Planck-Institut für Molekulare Genetik, Abteilung Wittmann, Berlin, Germany.
P
P
Nowotny
M
M
Rühl
V
V
Nowotny
R P
RP
May
N
N
Burkhardt
H
H
Voss
K H
KH
Nierhaus
D004926:Escherichia coli; D009502:Neutrons; D011487:Protein Conformation; D012269:Ribosomal Proteins / Q000737:chemistry*; D012270:Ribosomes / Q000737:chemistry*; D012542:Scattering, Radiation; D012996:Solutions
D012269:Ribosomal Proteins; D012996:Solutions