<i>In vitro</i> titration data in comparison with published results.

<p>a) Glucose biosensor measurements from Deuschle et al (2005) compared with titrations using purified protein extracted and measured as per the <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0034512#s2" target="_blank">Materials and Methods</a> section (n = 3 independent protein preparations, with 3 FRET ratio measurements per ligand concentration). b) Glutamine biosensor measurements from Yang et al (2010) compared with titrations titrations using purified protein extracted and measured as per the <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0034512#s2" target="_blank">Materials and Methods</a> section (n = 3 independent protein preparations, with 3 FRET ratio measurements per ligand concentration, error bars represent one standard deviation of the mean). Inset depicts a zoomed in view of the lower concentrations of glutamine.