FIGURE 1.
(A) Kinetics of in vitro reconstitution of 30S ribosomal subunits at the indicated temperatures in the presence (closed symbols) or absence (open symbols) of the chaperones (DnaK, DnaJ, GrpE + ATP). At the indicated times, an aliquot was withdrawn from the reconstitution mixture, complemented with native 50S subunits and assayed for poly(Phe) synthesis at 20°C for 2 h. For details, see Materials and Methods. (B) ATPase activity of the DnaK system. The specific ATPase activity of DnaK (released phosphate/minute/DnaK) at 37°C was determined from the slope of the curve assuming a molecular mass for DnaK of 70 kD.
