Table 1.

Amino acid-type selectively ¹³C-labeled OmpG samples produced for sequence-specific assignments and distance measurements

Residue specific	[2-13C]- or [1,3-13C]-glycerol
GAFα,βYα,β (S)	2- and 1,3-uniform
GAVLS(Wα,β,γ)	2- and 1,3-TEMPQANDSG
RIGA(S)	2-SHLYGWAFV(QENDT)
GANDSH(LV)	1,3-MKINDT
GENDQPASR
GAFα,βYα,β SHVL

Amino acids in brackets were accidentally labeled to a lower degree due to active biochemical pathways. Samples in the left column were prepared by adding ¹³C, ¹⁵N-labeled amino acids (or as specified) to ¹⁵NH₄Cl-containing growth medium so all others appeared ¹⁵N- but not ¹³C-labeled. Samples in the right column were prepared by a “reverse” labeling scheme in which either [2-¹³C]- or [1,3-¹³C]-glycerol medium was used to produce the respective ¹³C-labeling pattern for the indicated amino acids, whereas all other amino acids were added in ¹⁵N-labeled form to the growth medium