Micro bio spin gel p 6 columns

Glul activity was assayed using the γ-glutamyltransferase assay as previously described^{67 (link)}. Briefly, WT and lf:Yap transgenic larvae or adult livers were lysed in 50 mM imidazole and samples were purified using micro bio-spin gel p-6 columns (BioRad). Lysates were incubated in activity buffer (50 mM imidazole, 50 mM L-glutamine, 25 mM hydroxylamine, 25 mM sodium arsenate, 2mM manganese chloride, 0.16 mM adenosine diphosphate) at 27 °C for 30 min. The reactions were quenched in stop solution (2.42% iron chloride and 1.45% trichloroacetic acid in 1.82 N hydrochloric acid). Absorbance was read at 520 nm and a calibration curve of glutamyl-γ-hydroxamate (Sigma) was used to calculate nmol of product formed.