Fig. 4.

The effect of an aspB null mutation on glutamate metabolism. Having putatively identified metabolites from ESI-TOF MS negative ionisation mode the relative metabolite levels were analysed related to the lesion in metabolism caused by aspB mutation (black cross). Metabolites in black typeface show an increase in relative abundance in the aspB strain and in grey typeface a decrease. *p value < 0.05 between the C. jejuni NCTC 11168 (black bars) and aspA strain (white bars) metabolite levels, displayed as a % of the total ion count. Glutamate can be seen to have undergone a significant sevenfold increase and aspartate a slight decrease in the aspB mutant. Many metabolites linked to glutamate can be seen to have undergone an increase in the aspB strain