Aliphatic 1H and 13C resonance assignments for the 26-10 antibody VL domain derived from heteronuclear multidimensional NMR spectroscopy.

Extensive 1H and 13C assignments have been obtained for the aliphatic resonances of a uniformly 13C- and 15N-labeled recombinant VL domain from the anti-digoxin antibody 26-10. Four-dimensional triple resonance NMR data acquired with the HNCAHA and HN(CO)CAHA pulse sequences [Kay et al. (1992) J. Magn. Reson., 98, 443-450] afforded assignments for the backbone HN, N, H alpha and C alpha resonances. These data confirm and extend HN, N and H alpha assignments derived previously from three-dimensional 1H-15N NMR studies of uniformly 15N-labeled VL domain [Constantine et al. (1992), Biochemistry, 31, 5033-5043]. The identified H alpha and C alpha resonances provided a starting point for assigning the side-chain aliphatic 1H and 13C resonances using three-dimensional HCCH-COSY and HCCH-TOCSY experiments [Clore et al. (1990), Biochemistry, 29, 8172-8184]. The C alpha and C beta chemical shifts are correlated with the VL domain secondary structure. The extensive set of side-chain assignments obtained will allow a detailed comparison to be made between the solution structure of the isolated VL domain and the X-ray structure of the VL domain within the 26-10 Fab.