th  - 1987 - 51st ENC Conference

WK18
21) NMR METHODS FOR ~ SYSTEM IDENTIFICATIDN IN LARCE
PROTEINS
CLzudi~ Dalvi% S.S. Naru~* and Peter E. Wright
Department of uc~ecular
R ~ I m ~ of Scripps
1~ North Tcrr~y Pines Road
Recent deve~pments in 2D NMR method~y now make it possible to
obtain extensive and ~m~=uous spin system assignments for ~ of
malecmlar weight up to- 20,O00d. Phase sensi~ve double quantum spe~:~Fy
and Hartman-Hahn techniques are particularly im~l~ Appli~ticvs of these
OdS to ]~g~emog]~l~n (M- 16,000) and myog~l~n (M ~ 18,000) wi~ be
• Acc~n of dc~l~ quantum spectr~ wi'~ d~f&~nt • values
impcm-tant to a.1]Dw di~erenl~ d direct and r~mote connectivj.i~.es and for
spectr~ mmpl~f-ic~,',n and edii~ng. The double quan~nn experiment is
well,bred for detection of weak, ]c~g-~d~ge ~ and can ~ e
una.mhiguous czmuectiv'ities between the aroma~c and alipha~c ~ of
~ e spin systems. R ~ frame NOESY experiments are inva.luahle in
studying exchange troces~s between different conforma~kmal suhstates of
]~emq~hin. We show that Hart~an-Hahn coherence transfer experiments
can be used to ~d~ amino acid spin systems in a ~ of malecular
weight 38,000; a::mv~ COSY techniques are iI~r~.~le far a ~ of
size.