TABLE 2.

Estimation of molecular size in solution by DLSa

Protein and bufferbTotal mass (%)RH (nm)CP/RH (%)RH range (nm)cSubunits per oligomerPredominating subunits (oligomer range)Baseline error
cpn10Mt
    A99.993.7010.43.51-3.898.0,d 5.9e71.012
    B95.9, 4.14.31, 36.7729.8, 54.13.67-4.9513.3f14 (7-14+)1.001
GroES
    C99.93.7010.23.51-3.898.0,d 5.9e71.003
    D99.7, 0.34.27, 29.1024.8, 21.23.74-4.8012.9f14 (7-14+)1.003
  • a Volume shape hydration (VSH) models with hydrodynamic radii (RH) calculated from crystal structure data. RH for cpn10Mt heptamer without base loops, 3.54 nm; RH for cpn10Mt heptamer, 3.92 nm; RH for cpn10Mt tetradecamer, 4.39 nm; RH for GroES heptamer without base loops, 3.49 nm.

  • b Buffers: A, 2.3 mg of cpn10Mt per ml in 100 mM TrisHCl (pH 6.8), 50 mM KCl; B, 2.65 mg of cpn10Mt per ml in 40 mM sodium acetate (pH 5.4), 8 mM CaCl2; C, 0.56 mg of GroES per ml in 40 mM sodium acetate (pH 7.4); D, 0.5 mg of GroES per ml in 36 mM sodium acetate (pH 7.4), 20 mM CaCl2.

  • c Estimated from polydispersity.

  • d Corresponding to VSH model a.

  • e Corresponding to VSH model b.

  • f Corresponding to VSH model c.