Table 2. Structural parameters obtained from the SAXS data of proteins in solution.

	R g,G † (Å)	R g,p(r) ‡ (Å)	D max § (Å)	Vp¶ (Å3)	MMcalculated †† (kDa)	MMSAXS,Vp ‡‡ (kDa)	Conformer
RsbV–RsbW	34.90 ± 0.30	35.91 ± 0.25	114.0	161000	30.2	133.6	Hetero-octamer
RsbV1–104–RsbW5–145	32.21 ± 0.29	34.66 ± 0.22	108.0	131000	27.8	108.7	Hetero-octamer
Ball-shaped octamer	30.04 ± 0.01	29.55 ± 0.07	85.0	115000	22.4		Hetero-octamer
Ribbon-shaped octamer	35.87 ± 0.01	36.13 ± 0.07	117.0	137000	22.4		Hetero-octamer

^†Radius of gyration obtained from the scattering data by Guinier analysis.

^‡Radius of gyration obtained from the p(r) function by GNOM.

^§Maximum dimension obtained from the p(r) function by GNOM.

^¶Porod volume obtained from the p(r) function by GNOM.

^††Molecular mass obtained from the amino-acid sequence of the heterodimeric protein.

^‡‡Molecular mass calculated by multiplying Vp by the average protein density ρ_m = 0.83 × 10⁻³ kDa Å⁻³.