Ata.RESULTSC. jejuni LOS Structure–To investigate the LOS/TLR4 structure-function connection of livestock versus non-livestock C.JULY 5, 2013 ?VOLUME 288 ?NUMBERjejuni, the LOSs from 15 strains (seven in the livestock cluster (like reference strain 11168H) and eight from the nonlivestock cluster (21)) have been purified. Adverse ion MALDI-TOF MS was performed on both the intact and the O-deacylated LOS species. MALDI-TOF MS was also performed on the LA isolated from the LOSs of ten strains. On the seven livestockassociated strains, three have been human clinical isolates from diarrheal ( blood) patients, two have been from asymptomatic carriers, and two have been from colonized livestock. In the eight non-liveJOURNAL OF BIOLOGICAL CHEMISTRYC. jejuni LOS-TLR4 InteractionsTABLE 1 Molecular and fragment ion peaks in spectrum of O-deacylated 40917 (A) and intact 31481 LOS (B)aDPLA represents 2-amino-2-deoxy-D-hexose and two,3-diamino-2,3-dideoxy-Dhexose (HexN-HexN3N) with two phosphate (P) and three hydroxymyristic acid (C14:0(3-OH)) moieties immediately after O-deacylation. b Italics represent non-reducing terminal B-type OS fragment ions from prompt fragmentation. c Non-reducing terminal B-type OS fragment ions from prompt fragmentation with loss of CO2. d Bold represents decreasing terminal Y-type LA fragment ions from prompt fragmentation. e Prompt fragmentation creating LA ions with loss of H3PO4. f DPLA represents HexN-HexN3N with two phosphate (P), four hydroxymyristic acid (C14:0(3-OH)), and two palmitic acid (C16:0) moieties.stock-associated strains, 4 have been human clinical isolates from diarrheal ( blood) sufferers, and four have been from asymptomatic carriers. Representative spectra of low and high resolution MS spectra of O-deacylated and intact LOS from two of the 15 strains are shown in Fig. 1, A and B, respectively, with proposed compositions for the important molecular and fragment ions presented in Table 1, A and B, respectively.5-Chloro-2-tetralone web The majority of OS compositions proposed for the 15 strains are based on the non-reducing terminal B-type fragment ions of O-deacylated LOS (Table two) (26) and also the elements on the C.Fmoc-Bip(4,4′)-OH Purity jejuni OS reported previously (19, 27).PMID:33611692 For strains 32787 and 43205 with unusual OS structure, information were obtained from high resolution negative ion MALDIperformed on the Synapt G2 higher definition MS system with an orthogonal TOF mass analyzer (Table 2B). As shown inside the inset spectrum on the intact LOS from strain 31481 (Fig. 1B), base-line separation of monoisotopic peaks for the intact molecular (M H) ions was obtained. Normally, OS fragment ion peaks in the unfavorable ion MALDI spectra with the intact or O-deacylated LOS could be distinguished by the presence of lower mass peaks for the characteristic additional losses of CO2 (44 Da) from 3-deoxy-D-manno-oct-2-ulosonic acid (Kdo) and loss of the labile Kdo moiety (220 Da) (Fig. 1, A and B, and Table 1, A and B). Compositions proposed for monoisotopic peaks for the highest mass OS fragment ions that were detected for intact LOS from strains 32787 and 43205 are presented in Table 2B. The monoisotopic masses of these prompt B-type oligosaccharide ions had been analyzed having a personal computer algorithm to establish possible compositions (28). The monosaccharides and also other components employed in the algorithm integrated PEA, phosphate, Gly, and O-acetate, which have been reported previously in the LOS of C. jejuni (19, 27). For strain 32787, the peak observed at m/z 2282.7402 was constant using a composition of two Kdo,.