FIG 4.
(A) MS/MS spectrum of NBD-F1-P (M − H)− = 369.4 m/z ion with the expected fragments at 79, 97, 179, 289, and 323 m/z. The proposed structures of the expected fragments are shown on the right. (B) MS/MS spectrum of NBD-F1-PP (M − H)− = 449.5 m/z ion generated from the phosphoryl transfer reaction between ATP and F1-P catalyzed by MfnE with the expected fragments at 79, 159, 177, and 403 m/z. The proposed structures of the expected fragment are shown on the right.