Assay of Cystathionine-γ-synthase (CaStr2p) activity determination.

The study aimed to obtain conditions optimal for the activity of Candida albicans cystathionine-γ-synthase (CaStr2p) determination. The selection of appropriate reaction conditions included the identification of the reaction buffer and its pH, substrate, and enzyme concentrations. The activity of Str2p was measured by the detection of decrease of the substrate L-cysteine (L-Cys) via LC/MS system with pre-column derivatization. Mass spectra were recorded using an Agilent 6470A triple quadrupole (6470 Triple Quad LC/MS, Agilent Technologies, Waldbronn, Germany) LC/MS system (1260 Infinity II, Agilent Technologies,Waldbronn, Germany) with electrospray ionization source (ESI). L-Cys reacts with 5,5’-dithiobis(2-nitrobenzoic acid) (DTNB) to produce a L-Cys-TNB complex, that can be also detected by the diode array detector (HPLC-DAD). Optimal conditions for L-Cys-TNB complex detection included identification of mobile phase, elution profile, injection volume, and most suitable wavelengths for the detection have been identified. This dataset contains the description of the methodology, and the set of selected chromatographs obtained for control as well as enzymatic reaction samples. The studies were financially supported by the project OPUS 20 financed by the National Science Centre (No. UMO-2020/39/B/NZ7/01519).