Biomedical Engineering Reference
In-Depth Information
Figure
7.5
15
N-R
1r
relaxation dispersion for V167 in loop 6 in apo-TIM. A
relaxation data was acquired at 14.1 T and 298 K. The R
1r
dispersion
data was fit with the fast-limit version of eqn (7.8) to give k
ex
5 8900 ยก
1600 s
21
. (B) The location of the flexible residue in (A) is shown as a
black sphere on the ribbon rendering of loop 6 in TIM in the open (dark)
and closed (light) conformations.
value was in agreement with a number of biochemical experiments that suggest
loop 6 motion is rate-limiting in the physiological direction of conversion of
DHAP to GAP.
7.6 Conclusions
Novel NMR pulse sequences and innovative isotopic labelling strategies have
enabled detailed investigation of ms-ms motions in large enzymes and enzyme
complexes with molecular weights in the hundreds of kDa. These advances will
significantly expand the interesting biological targets that can be studied in
great detail by NMR spectroscopy.
Acknowledgements
We thank Dr James Lipchock and Greg Manley for providing relaxation data
for IGPS and Dr Rebecca Berlow for TIM R
1r
data. JPL acknowledges
support from NIH R01-GM070823 and SKW acknowledges funding from an
NIH Biophysical training grant T32GM008283.
References
1. M. Akke and A. G. Palmer, J. Am. Chem. Soc., 1996, 118, 911.
2. J. C. Williams and A. E. McDermott, Biochemistry, 1995, 34, 8309.
3. H. Beach, R. Cole, M. L. Gill and J. P. Loria, J. Am. Chem. Soc., 2005,
127, 9167.
