ENO1 and infection: This study revealed a large increase in the extracellular accumulation of GABA during the incompatible interactions between P. vulgaris and Pph. GABA levels have previously been reported to increase in response to tomato leaf infection by Cladosporium fulvum (Solomon & Oliver 2001), and in response to infection of Arabidopsis thaliana with Pto DC3000 (Ward et al. 2010).