No differences were observed in the production of the various LOS forms between the two variants of 11168, the genome sequenced and original isolate. The higher-Mr form of C. jejuni 11168 (~6 kDa) learn more exhibited GM1-like mimicry and, therefore, corresponded to the previously

characterized LOS [20, 21, 23]. Studies with CTB, a well-known binder of GM1 ganglisoide [25], confirmed the presence of a GM1 mimic in this form of NCTC 11168. Similar mimicry was also detected among the higher-Mr LOS forms of the other isolates of humans and chickens tested, but not in the lower-Mr form of any other strains. The weak binding of CTB to the higher-Mr LOS variant of C. jejuni 520 reflects that the saccharide terminus may exhibit some ganglioside-related mimic, though not GM1 mimicry. This is shown by the CTB binding to ganglioside-related structures not just GM1 and PNA did not confirm the presence of a terminal β-D-Gal-(1→3)-D-GalNAc. A CTB binding affinity study showed that the lower-Mr form of C. jejuni NCTC 11168 failed to bind to the lectin. Nevertheless, the results of the present study showed that it contains a β-D-Gal-(1→3)-D-GalNAc disaccharide moiety

in the core consistent with production of a truncated (because of its lower molecular mass), but related form, of the check details NCTC 11168 structure previously described [21], and is an asialo-GM1-like structure. Conclusion In conclusion, this study identified the presence of a lower-Mr LOS form produced by C. jejuni NCTC 11168 and other clinical and avian strains. The lower-Mr

form production was growth-temperature related as higher quantities were observed at 42°C. It is tempting to speculate that the occurrence new of greater quantities of this form at avian body temperature might play a role in an adaptative mechanism to aid commensal colonization of such hosts. Alternatively, changes in the relative production of the two forms of LOS at the higher temperature could be related to a stress response. Such a phenomenon has already been seen with increased oxygen tension in the growth atmosphere of C. jejuni influencing the structural mimicry exhibited in the LOS of this bacterium [31]. Although an intriguing phenomenon, further investigations are required to evaluate these alternate hypotheses. Methods Bacterial strains and growth conditions The original isolate of C. jejuni NCTC 11168 (11168-O) that had been characterized by Gaynor et al. (2004) [17], C. jejuni 11168-GS (genome-sequenced NCTC 11168) that had been sequenced and annotated at the Sanger Centre (Hinxton, Cambridge, UK) [16], and strain 81116 were kindly supplied by D.J. Newell (Veterinary Laboratories Agency, Weybridge, UK). C. jejuni RM1221 has been described [32] and was kindly provided by R. E. Mandrell (United States Department of Agriculture, CA, USA.). C.