Fig. 2. Conformational dynamics of GB3L.
(A) Order parameters in the buffer only, with anionic SNPs (aSNP), and in E. coli cells. The presence of anionic SNPs extends the dynamic observation time window so that picosecond to microsecond dynamics (S2SNP) can be detected, which is undetectable in the conventional model-free analysis of 15N R1, R2, and NOE data measured in the buffer only (S2buf). GB3L S2 in E. coli cells (S2cell) agrees better with S2SNP, suggesting that the dynamics detected in cells is probably on picosecond to microsecond timescale. Picosecond to millisecond timescale S2 fitted from backbone amide 1H-15N RDCs (S2RDC) was also included (only residues with at least two sets of experimental RDCs are shown). (B) Correlation of S2 in E. coli cells (S2cell) measured at 600 and 900 MHz fields. Two residues D19 and T21 show conformational exchanges (in red). Error bars (except for S2RDC) are SEM (n = 3 independent experiments). Error bars for S2RDC are SD from 10 independent ensemble fittings.