Fig. 3. Ap synthesises and secretes isoleucine in the presence of Lp.

The stacked bars represent the relative amount of Ile isotopologues measured in the supernatant of liquid holidic medium of bacterial cultures grown in holidic medium lacking Ile (-Ile, left section), complete holidic medium (filled black circles, central section) or His (-His, right section) all containing uniformly labelled ¹³C-glucose. Heavy-labelled Ile isotopologues were measured using LC–MS in samples collected after 24 h or 48 h of bacterial growth and displayed as metabolite peak area. The number of heavy carbons incorporated per Ile molecule is indicated as m + n, where m = molecular mass of the metabolite and n = the number of ¹³C. Filled black circles represent the presence of specific bacteria in the culture. Open black circles represent the absence of specific bacteria. For each condition three independent bacterial cultures were sampled at 24 h and 48 h. The plots represent the mean amount of the detected isotopologues per condition and the error bars represent the s.e.m. Source data are provided as a Source Data file.