TABLE 4.

Lipid A fragment ion peaks of O-deacylated LOS (A) and GlcN-GlcN lipid A fragment ion peaks of intact LOS (B)

^a Reducing terminal Y-type LA fragment ions of O-deacylated LA composed of two GlcN3N-GlcN3N (four amides), two GlcN-GlcN (two amides), or GlcN-GlcN3N (three amides) moieties. Typically, only DPLA without PEA was detected.

^b Italics represent reducing terminal Y-type LA fragment ions that are <28 Da and have a C12:0(3-OH) replacing a C14:0(3-OH) or a C14:0 replacing a C16:0 moiety.

^c Reducing terminal Y-type LA fragment ions of intact LA. As an example, fragment ions of LA composed of GlcN-GlcN (two amides) are presented.