Figure 2.

2D ¹H-¹³C NMR spectra for Ile δ1 methyl and Phe δ-CH of Vibrio FliG_MC fragment

The spectra were measured using an 800 MHz spectrometer at 288 K equipped with a cryogenic probe.

(A) Overlaid HMQC spectra for FliG_MC (black) and its I331L mutant (red). The I331 signal was not detected in the mutant spectra.

(B) Sequence-specific signal assignment for Ile δ1 methyl. The assignment of each of the 16 Ile residues is shown in Figure S2. For I151 and I213 residues, an unambiguous signal could not be assigned.

(C) Sequence-specific signal assignment for Phe δ-CH mapped on ¹H-¹³C TROSY-HSQC spectrum. The six Phe residues were assigned using ¹³C edited NOESY measurement (Figures S3B–S3D). ∗ indicates impurity.

(D and E) Structure of the isotope labeled at δ1 methyl of isoleucine and SAIL Phenylalanine are shown, respectively. ∗ indicates ¹³C.